HiSilicon PCIe tune and trace device (PTT) is a PCIe Root Complex
integrated Endpoint (RCiEP) device, providing the capability
to dynamically monitor and tune the PCIe traffic (tune),
and trace the TLP headers (trace).
PTT tune is designed for monitoring and adjusting PCIe link parameters.
We provide several parameters of the PCIe link. Through the driver,
user can adjust the value of certain parameter to affect the PCIe link
for the purpose of enhancing the performance in certian situation.
PTT trace is designed for dumping the TLP headers to the memory, which
can be used to analyze the transactions and usage condition of the PCIe
Link. Users can choose filters to trace headers, by either requester
ID, or those downstream of a set of Root Ports on the same core of the
PTT device. It's also supported to trace the headers of certain type and
of certain direction.
The driver registers a PMU device for each PTT device. The trace can
be used through `perf record` and the traced headers can be decoded
by `perf report`. The perf command support for the device is also
added in this patchset. The tune can be used through the sysfs
attributes of related PMU device. See the documentation for the
detailed usage.
Change since v6:
- Fix W=1 errors reported by lkp test, thanks
Change since v5:
- Squash the PMU patch into PATCH 2 suggested by John
- refine the commit message of PATCH 1 and some comments
Link: https://lore.kernel.org/lkml/[email protected]/
Change since v4:
Address the comments from Jonathan, John and Ma Ca, thanks.
- Use devm* also for allocating the DMA buffers
- Remove the IRQ handler stub in Patch 2
- Make functions waiting for hardware state return boolean
- Manual remove the PMU device as it should be removed first
- Modifier the orders in probe and removal to make them matched well
- Make available {directions,type,format} array const and non-global
- Using the right filter list in filters show and well protect the
list with mutex
- Record the trace status with a boolean @started rather than enum
- Optimize the process of finding the PTT devices of the perf-tool
Link: https://lore.kernel.org/linux-pci/[email protected]/
Change since v3:
Address the comments from Jonathan and John, thanks.
- drop members in the common struct which can be get on the fly
- reduce buffer struct and organize the buffers with array instead of list
- reduce the DMA reset wait time to avoid long time busy loop
- split the available_filters sysfs attribute into two files, for root port
and requester respectively. Update the documentation accordingly
- make IOMMU mapping check earlier in probe to avoid race condition. Also
make IOMMU quirk patch prior to driver in the series
- Cleanups and typos fixes from John and Jonathan
Link: https://lore.kernel.org/linux-pci/[email protected]/
Change since v2:
- address the comments from Mathieu, thanks.
- rename the directory to ptt to match the function of the device
- spinoff the declarations to a separate header
- split the trace function to several patches
- some other comments.
- make default smmu domain type of PTT device to identity
Drop the RMR as it's not recommended and use an iommu_def_domain_type
quirk to passthrough the device DMA as suggested by Robin.
Link: https://lore.kernel.org/linux-pci/[email protected]/
Change since v1:
- switch the user interface of trace to perf from debugfs
- switch the user interface of tune to sysfs from debugfs
- add perf tool support to start trace and decode the trace data
- address the comments of documentation from Bjorn
- add RMR[1] support of the device as trace works in RMR mode or
direct DMA mode. RMR support is achieved by common APIs rather
than the APIs implemented in [1].
Link: https://lore.kernel.org/lkml/[email protected]/
[1] https://lore.kernel.org/linux-acpi/[email protected]/
Qi Liu (1):
perf tool: Add support for HiSilicon PCIe Tune and Trace device driver
Yicong Yang (6):
iommu/arm-smmu-v3: Make default domain type of HiSilicon PTT device to
identity
hwtracing: Add trace function support for HiSilicon PCIe Tune and
Trace device
hisi_ptt: Add support for dynamically updating the filter list
hisi_ptt: Add tune function support for HiSilicon PCIe Tune and Trace
device
docs: Add HiSilicon PTT device driver documentation
MAINTAINERS: Add maintainer for HiSilicon PTT driver
Documentation/trace/hisi-ptt.rst | 303 +++++
MAINTAINERS | 7 +
drivers/Makefile | 1 +
drivers/hwtracing/Kconfig | 2 +
drivers/hwtracing/ptt/Kconfig | 12 +
drivers/hwtracing/ptt/Makefile | 2 +
drivers/hwtracing/ptt/hisi_ptt.c | 1161 +++++++++++++++++
drivers/hwtracing/ptt/hisi_ptt.h | 220 ++++
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 16 +
tools/perf/arch/arm/util/auxtrace.c | 76 +-
tools/perf/arch/arm/util/pmu.c | 3 +
tools/perf/arch/arm64/util/Build | 2 +-
tools/perf/arch/arm64/util/hisi_ptt.c | 195 +++
tools/perf/util/Build | 2 +
tools/perf/util/auxtrace.c | 4 +
tools/perf/util/auxtrace.h | 1 +
tools/perf/util/hisi-ptt-decoder/Build | 1 +
.../hisi-ptt-decoder/hisi-ptt-pkt-decoder.c | 170 +++
.../hisi-ptt-decoder/hisi-ptt-pkt-decoder.h | 28 +
tools/perf/util/hisi_ptt.c | 218 ++++
tools/perf/util/hisi_ptt.h | 28 +
21 files changed, 2448 insertions(+), 4 deletions(-)
create mode 100644 Documentation/trace/hisi-ptt.rst
create mode 100644 drivers/hwtracing/ptt/Kconfig
create mode 100644 drivers/hwtracing/ptt/Makefile
create mode 100644 drivers/hwtracing/ptt/hisi_ptt.c
create mode 100644 drivers/hwtracing/ptt/hisi_ptt.h
create mode 100644 tools/perf/arch/arm64/util/hisi_ptt.c
create mode 100644 tools/perf/util/hisi-ptt-decoder/Build
create mode 100644 tools/perf/util/hisi-ptt-decoder/hisi-ptt-pkt-decoder.c
create mode 100644 tools/perf/util/hisi-ptt-decoder/hisi-ptt-pkt-decoder.h
create mode 100644 tools/perf/util/hisi_ptt.c
create mode 100644 tools/perf/util/hisi_ptt.h
--
2.24.0
The PCIe devices supported by the PTT trace can be removed/rescanned by
hotplug or through sysfs. Add support for dynamically updating the
available filter list by registering a PCI bus notifier block. Then user
can always get latest information about available tracing filters and
driver can block the invalid filters of which related devices no longer
exist in the system.
Signed-off-by: Yicong Yang <[email protected]>
Reviewed-by: Jonathan Cameron <[email protected]>
---
drivers/hwtracing/ptt/hisi_ptt.c | 159 ++++++++++++++++++++++++++++---
drivers/hwtracing/ptt/hisi_ptt.h | 34 +++++++
2 files changed, 180 insertions(+), 13 deletions(-)
diff --git a/drivers/hwtracing/ptt/hisi_ptt.c b/drivers/hwtracing/ptt/hisi_ptt.c
index 242b41870380..b1958ac20372 100644
--- a/drivers/hwtracing/ptt/hisi_ptt.c
+++ b/drivers/hwtracing/ptt/hisi_ptt.c
@@ -270,27 +270,121 @@ static int hisi_ptt_register_irq(struct hisi_ptt *hisi_ptt)
return 0;
}
-static int hisi_ptt_init_filters(struct pci_dev *pdev, void *data)
+static void hisi_ptt_update_filters(struct work_struct *work)
{
+ struct delayed_work *delayed_work = to_delayed_work(work);
+ struct hisi_ptt_filter_update_info info;
struct hisi_ptt_filter_desc *filter;
- struct hisi_ptt *hisi_ptt = data;
struct list_head *target_list;
+ struct hisi_ptt *hisi_ptt;
- target_list = pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT ?
- &hisi_ptt->port_filters : &hisi_ptt->req_filters;
+ hisi_ptt = container_of(delayed_work, struct hisi_ptt, work);
- filter = kzalloc(sizeof(*filter), GFP_KERNEL);
- if (!filter) {
- pci_err(hisi_ptt->pdev, "failed to add filter %s\n", pci_name(pdev));
- return -ENOMEM;
+ if (!mutex_trylock(&hisi_ptt->mutex)) {
+ schedule_delayed_work(&hisi_ptt->work, HISI_PTT_WORK_DELAY_MS);
+ return;
}
- filter->pdev = pdev;
- list_add_tail(&filter->list, target_list);
+ while (kfifo_get(&hisi_ptt->filter_update_kfifo, &info)) {
+ bool is_port = pci_pcie_type(info.pdev) == PCI_EXP_TYPE_ROOT_PORT;
+ u16 val = hisi_ptt_get_filter_val(info.pdev);
- /* Update the available port mask */
- if (pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT)
- hisi_ptt->port_mask |= hisi_ptt_get_filter_val(pdev);
+ target_list = is_port ? &hisi_ptt->port_filters : &hisi_ptt->req_filters;
+
+ if (info.is_add) {
+ filter = kzalloc(sizeof(*filter), GFP_KERNEL);
+ if (!filter) {
+ pci_err(hisi_ptt->pdev, "failed to add filter %s\n",
+ pci_name(info.pdev));
+ continue;
+ }
+
+ filter->pdev = info.pdev;
+ list_add_tail(&filter->list, target_list);
+ } else {
+ list_for_each_entry(filter, target_list, list)
+ if (hisi_ptt_get_filter_val(filter->pdev) == val) {
+ list_del(&filter->list);
+ kfree(filter);
+ break;
+ }
+ }
+
+ /* Update the available port mask */
+ if (!is_port)
+ continue;
+
+ if (info.is_add)
+ hisi_ptt->port_mask |= val;
+ else
+ hisi_ptt->port_mask &= ~val;
+ }
+
+ mutex_unlock(&hisi_ptt->mutex);
+}
+
+static void hisi_ptt_update_fifo_in(struct hisi_ptt *hisi_ptt,
+ struct hisi_ptt_filter_update_info *info)
+{
+ struct pci_dev *root_port = pcie_find_root_port(info->pdev);
+ u32 port_devid;
+
+ if (!root_port)
+ return;
+
+ port_devid = PCI_DEVID(root_port->bus->number, root_port->devfn);
+ if (port_devid < hisi_ptt->lower ||
+ port_devid > hisi_ptt->upper)
+ return;
+
+ if (kfifo_in_spinlocked(&hisi_ptt->filter_update_kfifo, info, 1,
+ &hisi_ptt->filter_update_lock))
+ schedule_delayed_work(&hisi_ptt->work, 0);
+ else
+ pci_warn(hisi_ptt->pdev,
+ "filter update fifo overflow for target %s\n",
+ pci_name(info->pdev));
+}
+
+/*
+ * A PCI bus notifier is used here for dynamically updating the filter
+ * list.
+ */
+static int hisi_ptt_notifier_call(struct notifier_block *nb, unsigned long action,
+ void *data)
+{
+ struct hisi_ptt *hisi_ptt = container_of(nb, struct hisi_ptt, hisi_ptt_nb);
+ struct hisi_ptt_filter_update_info info;
+ struct device *dev = data;
+ struct pci_dev *pdev = to_pci_dev(dev);
+
+ info.pdev = pdev;
+
+ switch (action) {
+ case BUS_NOTIFY_ADD_DEVICE:
+ info.is_add = true;
+ break;
+ case BUS_NOTIFY_DEL_DEVICE:
+ info.is_add = false;
+ break;
+ default:
+ return 0;
+ }
+
+ hisi_ptt_update_fifo_in(hisi_ptt, &info);
+
+ return 0;
+}
+
+static int hisi_ptt_init_filters(struct pci_dev *pdev, void *data)
+{
+ struct hisi_ptt_filter_update_info info = {
+ .pdev = pdev,
+ .is_add = true,
+ };
+ struct hisi_ptt *hisi_ptt = data;
+
+ hisi_ptt_update_fifo_in(hisi_ptt, &info);
return 0;
}
@@ -318,6 +412,9 @@ static int hisi_ptt_init_ctrls(struct hisi_ptt *hisi_ptt)
int ret;
u32 reg;
+ INIT_DELAYED_WORK(&hisi_ptt->work, hisi_ptt_update_filters);
+ spin_lock_init(&hisi_ptt->filter_update_lock);
+ INIT_KFIFO(hisi_ptt->filter_update_kfifo);
INIT_LIST_HEAD(&hisi_ptt->port_filters);
INIT_LIST_HEAD(&hisi_ptt->req_filters);
@@ -334,6 +431,13 @@ static int hisi_ptt_init_ctrls(struct hisi_ptt *hisi_ptt)
hisi_ptt->upper = FIELD_GET(HISI_PTT_DEVICE_RANGE_UPPER, reg);
hisi_ptt->lower = FIELD_GET(HISI_PTT_DEVICE_RANGE_LOWER, reg);
+ /*
+ * No need to fail if the bus is NULL here as the device
+ * maybe hotplugged after the PTT driver probe, in which
+ * case we can detect the event and update the list as
+ * we register a bus notifier for dynamically updating
+ * the filter list.
+ */
bus = pci_find_bus(pci_domain_nr(pdev->bus), PCI_BUS_NUM(hisi_ptt->upper));
if (bus)
pci_walk_bus(bus, hisi_ptt_init_filters, hisi_ptt);
@@ -760,6 +864,31 @@ static int hisi_ptt_register_pmu(struct hisi_ptt *hisi_ptt)
return perf_pmu_register(&hisi_ptt->hisi_ptt_pmu, pmu_name, -1);
}
+static void hisi_ptt_unregister_filter_update_notifier(void *data)
+{
+ struct hisi_ptt *hisi_ptt = data;
+
+ bus_unregister_notifier(&pci_bus_type, &hisi_ptt->hisi_ptt_nb);
+
+ /* Cancel any work that has been queued */
+ cancel_delayed_work_sync(&hisi_ptt->work);
+}
+
+/* Register the bus notifier for dynamically updating the filter list */
+static int hisi_ptt_register_filter_update_notifier(struct hisi_ptt *hisi_ptt)
+{
+ int ret;
+
+ hisi_ptt->hisi_ptt_nb.notifier_call = hisi_ptt_notifier_call;
+ ret = bus_register_notifier(&pci_bus_type, &hisi_ptt->hisi_ptt_nb);
+ if (ret)
+ return ret;
+
+ return devm_add_action_or_reset(&hisi_ptt->pdev->dev,
+ hisi_ptt_unregister_filter_update_notifier,
+ hisi_ptt);
+}
+
/*
* The DMA of PTT trace can only use direct mapping, due to some
* hardware restriction. Check whether there is an IOMMU or the
@@ -832,6 +961,10 @@ static int hisi_ptt_probe(struct pci_dev *pdev,
return ret;
}
+ ret = hisi_ptt_register_filter_update_notifier(hisi_ptt);
+ if (ret)
+ pci_warn(pdev, "failed to register filter update notifier, ret = %d", ret);
+
ret = hisi_ptt_register_pmu(hisi_ptt);
if (ret) {
pci_err(pdev, "failed to register PMU device, ret = %d", ret);
diff --git a/drivers/hwtracing/ptt/hisi_ptt.h b/drivers/hwtracing/ptt/hisi_ptt.h
index 29b6d6293d6c..53805f6c9bc2 100644
--- a/drivers/hwtracing/ptt/hisi_ptt.h
+++ b/drivers/hwtracing/ptt/hisi_ptt.h
@@ -10,11 +10,15 @@
#define _HISI_PTT_H
#include <linux/bits.h>
+#include <linux/kfifo.h>
#include <linux/list.h>
#include <linux/mutex.h>
+#include <linux/notifier.h>
#include <linux/pci.h>
#include <linux/perf_event.h>
+#include <linux/spinlock.h>
#include <linux/types.h>
+#include <linux/workqueue.h>
#define DRV_NAME "hisi_ptt"
@@ -57,6 +61,12 @@
/* Wait time for hardware DMA to reset */
#define HISI_PTT_RESET_TIMEOUT_US 10UL
#define HISI_PTT_RESET_POLL_INTERVAL_US 1UL
+/* FIFO size for dynamically updating the PTT trace filter list. */
+#define HISI_PTT_FILTER_UPDATE_FIFO_SIZE 16
+/* Delay time for filter updating work */
+#define HISI_PTT_WORK_DELAY_MS 100UL
+/* Wait time for DMA hardware to reset */
+#define HISI_PTT_RESET_WAIT_MS 1000UL
/* Poll timeout and interval for waiting hardware work to finish */
#define HISI_PTT_WAIT_TRACE_TIMEOUT_US 100UL
#define HISI_PTT_WAIT_POLL_INTERVAL_US 10UL
@@ -112,6 +122,15 @@ struct hisi_ptt_filter_desc {
struct pci_dev *pdev;
};
+/**
+ * struct hisi_ptt_filter_update_info - information for PTT filter updating
+ * @pdev: the PCI device to update in the filter list
+ * @is_add: adding to the filter or not
+ */
+struct hisi_ptt_filter_update_info {
+ struct pci_dev *pdev;
+ bool is_add;
+};
/**
* struct hisi_ptt_pmu_buf - descriptor of the AUX buffer of PTT trace
@@ -139,9 +158,13 @@ struct hisi_ptt_pmu_buf {
* @port_filters: the filter list of root ports
* @req_filters: the filter list of requester ID
* @port_mask: port mask of the managed root ports
+ * @work: delayed work for filter updating
+ * @filter_update_lock: spinlock to protect the filter update fifo
+ * @filter_update_fifo: fifo of the filters waiting to update the filter list
*/
struct hisi_ptt {
struct hisi_ptt_trace_ctrl trace_ctrl;
+ struct notifier_block hisi_ptt_nb;
struct pmu hisi_ptt_pmu;
void __iomem *iobase;
struct pci_dev *pdev;
@@ -159,6 +182,17 @@ struct hisi_ptt {
struct list_head port_filters;
struct list_head req_filters;
u16 port_mask;
+
+ /*
+ * We use a delayed work here to avoid indefinitely waiting for
+ * the hisi_ptt->mutex which protecting the filter list. The
+ * work will be delayed only if the mutex can not be held,
+ * otherwise no delay will be applied.
+ */
+ struct delayed_work work;
+ spinlock_t filter_update_lock;
+ DECLARE_KFIFO(filter_update_kfifo, struct hisi_ptt_filter_update_info,
+ HISI_PTT_FILTER_UPDATE_FIFO_SIZE);
};
#define to_hisi_ptt(pmu) container_of(pmu, struct hisi_ptt, hisi_ptt_pmu)
--
2.24.0
The DMA operations of HiSilicon PTT device can only work properly with
identical mappings. So add a quirk for the device to force the domain
as passthrough.
Signed-off-by: Yicong Yang <[email protected]>
---
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
index 627a3ed5ee8f..5ec15ae2a9b1 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -2839,6 +2839,21 @@ static int arm_smmu_dev_disable_feature(struct device *dev,
}
}
+#define IS_HISI_PTT_DEVICE(pdev) ((pdev)->vendor == PCI_VENDOR_ID_HUAWEI && \
+ (pdev)->device == 0xa12e)
+
+static int arm_smmu_def_domain_type(struct device *dev)
+{
+ if (dev_is_pci(dev)) {
+ struct pci_dev *pdev = to_pci_dev(dev);
+
+ if (IS_HISI_PTT_DEVICE(pdev))
+ return IOMMU_DOMAIN_IDENTITY;
+ }
+
+ return 0;
+}
+
static struct iommu_ops arm_smmu_ops = {
.capable = arm_smmu_capable,
.domain_alloc = arm_smmu_domain_alloc,
@@ -2856,6 +2871,7 @@ static struct iommu_ops arm_smmu_ops = {
.sva_unbind = arm_smmu_sva_unbind,
.sva_get_pasid = arm_smmu_sva_get_pasid,
.page_response = arm_smmu_page_response,
+ .def_domain_type = arm_smmu_def_domain_type,
.pgsize_bitmap = -1UL, /* Restricted during device attach */
.owner = THIS_MODULE,
.default_domain_ops = &(const struct iommu_domain_ops) {
--
2.24.0
HiSilicon PCIe tune and trace device(PTT) is a PCIe Root Complex integrated
Endpoint(RCiEP) device, providing the capability to dynamically monitor and
tune the PCIe traffic, and trace the TLP headers.
Add the driver for the device to enable the trace function. Register PMU
device of PTT trace, then users can use trace through perf command. The
driver makes use of perf AUX trace and support following events to
configure the trace:
- filter: select Root port or Endpoint to trace
- type: select the type of traced TLP headers
- direction: select the direction of traced TLP headers
- format: select the data format of the traced TLP headers
This patch adds the driver part of PTT trace. The perf command support of
PTT trace is added in the following patch.
Signed-off-by: Yicong Yang <[email protected]>
Reviewed-by: Jonathan Cameron <[email protected]>
---
drivers/Makefile | 1 +
drivers/hwtracing/Kconfig | 2 +
drivers/hwtracing/ptt/Kconfig | 12 +
drivers/hwtracing/ptt/Makefile | 2 +
drivers/hwtracing/ptt/hisi_ptt.c | 874 +++++++++++++++++++++++++++++++
drivers/hwtracing/ptt/hisi_ptt.h | 166 ++++++
6 files changed, 1057 insertions(+)
create mode 100644 drivers/hwtracing/ptt/Kconfig
create mode 100644 drivers/hwtracing/ptt/Makefile
create mode 100644 drivers/hwtracing/ptt/hisi_ptt.c
create mode 100644 drivers/hwtracing/ptt/hisi_ptt.h
diff --git a/drivers/Makefile b/drivers/Makefile
index 020780b6b4d2..662d50599467 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -175,6 +175,7 @@ obj-$(CONFIG_USB4) += thunderbolt/
obj-$(CONFIG_CORESIGHT) += hwtracing/coresight/
obj-y += hwtracing/intel_th/
obj-$(CONFIG_STM) += hwtracing/stm/
+obj-$(CONFIG_HISI_PTT) += hwtracing/ptt/
obj-$(CONFIG_ANDROID) += android/
obj-$(CONFIG_NVMEM) += nvmem/
obj-$(CONFIG_FPGA) += fpga/
diff --git a/drivers/hwtracing/Kconfig b/drivers/hwtracing/Kconfig
index 13085835a636..911ee977103c 100644
--- a/drivers/hwtracing/Kconfig
+++ b/drivers/hwtracing/Kconfig
@@ -5,4 +5,6 @@ source "drivers/hwtracing/stm/Kconfig"
source "drivers/hwtracing/intel_th/Kconfig"
+source "drivers/hwtracing/ptt/Kconfig"
+
endmenu
diff --git a/drivers/hwtracing/ptt/Kconfig b/drivers/hwtracing/ptt/Kconfig
new file mode 100644
index 000000000000..8902a6f27563
--- /dev/null
+++ b/drivers/hwtracing/ptt/Kconfig
@@ -0,0 +1,12 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config HISI_PTT
+ tristate "HiSilicon PCIe Tune and Trace Device"
+ depends on ARM64 || (COMPILE_TEST && 64BIT)
+ depends on PCI && HAS_DMA && HAS_IOMEM && PERF_EVENTS
+ help
+ HiSilicon PCIe Tune and Trace Device exists as a PCIe RCiEP
+ device, and it provides support for PCIe traffic tuning and
+ tracing TLP headers to the memory.
+
+ This driver can also be built as a module. If so, the module
+ will be called hisi_ptt.
diff --git a/drivers/hwtracing/ptt/Makefile b/drivers/hwtracing/ptt/Makefile
new file mode 100644
index 000000000000..908c09a98161
--- /dev/null
+++ b/drivers/hwtracing/ptt/Makefile
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_HISI_PTT) += hisi_ptt.o
diff --git a/drivers/hwtracing/ptt/hisi_ptt.c b/drivers/hwtracing/ptt/hisi_ptt.c
new file mode 100644
index 000000000000..242b41870380
--- /dev/null
+++ b/drivers/hwtracing/ptt/hisi_ptt.c
@@ -0,0 +1,874 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Driver for HiSilicon PCIe tune and trace device
+ *
+ * Copyright (c) 2022 HiSilicon Technologies Co., Ltd.
+ * Author: Yicong Yang <[email protected]>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/delay.h>
+#include <linux/dma-iommu.h>
+#include <linux/dma-mapping.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/iommu.h>
+#include <linux/iopoll.h>
+#include <linux/module.h>
+#include <linux/sysfs.h>
+#include <linux/vmalloc.h>
+
+#include "hisi_ptt.h"
+
+static u16 hisi_ptt_get_filter_val(struct pci_dev *pdev)
+{
+ if (pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT)
+ return BIT(HISI_PCIE_CORE_PORT_ID(PCI_SLOT(pdev->devfn)));
+
+ return PCI_DEVID(pdev->bus->number, pdev->devfn);
+}
+
+static bool hisi_ptt_wait_trace_hw_idle(struct hisi_ptt *hisi_ptt)
+{
+ u32 val;
+
+ return !readl_poll_timeout_atomic(hisi_ptt->iobase + HISI_PTT_TRACE_STS,
+ val, val & HISI_PTT_TRACE_IDLE,
+ HISI_PTT_WAIT_POLL_INTERVAL_US,
+ HISI_PTT_WAIT_TRACE_TIMEOUT_US);
+}
+
+static bool hisi_ptt_wait_dma_reset_done(struct hisi_ptt *hisi_ptt)
+{
+ u32 val;
+
+ return !readl_poll_timeout_atomic(hisi_ptt->iobase + HISI_PTT_TRACE_WR_STS,
+ val, !val, HISI_PTT_RESET_POLL_INTERVAL_US,
+ HISI_PTT_RESET_TIMEOUT_US);
+}
+
+static void hisi_ptt_free_trace_buf(struct hisi_ptt *hisi_ptt)
+{
+ struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
+ struct device *dev = &hisi_ptt->pdev->dev;
+ int i;
+
+ if (!ctrl->trace_buf)
+ return;
+
+ for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; i++) {
+ if (ctrl->trace_buf[i].addr)
+ dmam_free_coherent(dev, HISI_PTT_TRACE_BUF_SIZE,
+ ctrl->trace_buf[i].addr,
+ ctrl->trace_buf[i].dma);
+ }
+
+ devm_kfree(dev, ctrl->trace_buf);
+ ctrl->trace_buf = NULL;
+}
+
+static int hisi_ptt_alloc_trace_buf(struct hisi_ptt *hisi_ptt)
+{
+ struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
+ struct device *dev = &hisi_ptt->pdev->dev;
+ int i;
+
+ hisi_ptt->trace_ctrl.buf_index = 0;
+
+ /* If the trace buffer has already been allocated, zero it. */
+ if (ctrl->trace_buf) {
+ for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; i++)
+ memset(ctrl->trace_buf[i].addr, 0, HISI_PTT_TRACE_BUF_SIZE);
+ return 0;
+ }
+
+ ctrl->trace_buf = devm_kcalloc(dev, HISI_PTT_TRACE_BUF_CNT,
+ sizeof(struct hisi_ptt_dma_buffer), GFP_KERNEL);
+ if (!ctrl->trace_buf)
+ return -ENOMEM;
+
+ for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; ++i) {
+ ctrl->trace_buf[i].addr = dmam_alloc_coherent(dev, HISI_PTT_TRACE_BUF_SIZE,
+ &ctrl->trace_buf[i].dma,
+ GFP_KERNEL);
+ if (!ctrl->trace_buf[i].addr) {
+ hisi_ptt_free_trace_buf(hisi_ptt);
+ return -ENOMEM;
+ }
+ }
+
+ return 0;
+}
+
+static void hisi_ptt_trace_end(struct hisi_ptt *hisi_ptt)
+{
+ writel(0, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
+ hisi_ptt->trace_ctrl.started = false;
+}
+
+static int hisi_ptt_trace_start(struct hisi_ptt *hisi_ptt)
+{
+ struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
+ u32 val;
+ int i;
+
+ /* Check device idle before start trace */
+ if (!hisi_ptt_wait_trace_hw_idle(hisi_ptt)) {
+ pci_err(hisi_ptt->pdev, "Failed to start trace, the device is still busy\n");
+ return -EBUSY;
+ }
+
+ ctrl->started = true;
+
+ /* Reset the DMA before start tracing */
+ val = readl(hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
+ val |= HISI_PTT_TRACE_CTRL_RST;
+ writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
+
+ hisi_ptt_wait_dma_reset_done(hisi_ptt);
+
+ val = readl(hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
+ val &= ~HISI_PTT_TRACE_CTRL_RST;
+ writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
+
+ /* Clear the interrupt status */
+ writel(HISI_PTT_TRACE_INT_STAT_MASK, hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
+ writel(0, hisi_ptt->iobase + HISI_PTT_TRACE_INT_MASK);
+
+ /* Configure the trace DMA buffer */
+ for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; i++) {
+ writel(lower_32_bits(ctrl->trace_buf[i].dma),
+ hisi_ptt->iobase + HISI_PTT_TRACE_ADDR_BASE_LO_0 +
+ i * HISI_PTT_TRACE_ADDR_STRIDE);
+ writel(upper_32_bits(ctrl->trace_buf[i].dma),
+ hisi_ptt->iobase + HISI_PTT_TRACE_ADDR_BASE_HI_0 +
+ i * HISI_PTT_TRACE_ADDR_STRIDE);
+ }
+ writel(HISI_PTT_TRACE_BUF_SIZE, hisi_ptt->iobase + HISI_PTT_TRACE_ADDR_SIZE);
+
+ /* Set the trace control register */
+ val = FIELD_PREP(HISI_PTT_TRACE_CTRL_TYPE_SEL, ctrl->type);
+ val |= FIELD_PREP(HISI_PTT_TRACE_CTRL_RXTX_SEL, ctrl->direction);
+ val |= FIELD_PREP(HISI_PTT_TRACE_CTRL_DATA_FORMAT, ctrl->format);
+ val |= FIELD_PREP(HISI_PTT_TRACE_CTRL_TARGET_SEL, hisi_ptt->trace_ctrl.filter);
+ if (!hisi_ptt->trace_ctrl.is_port)
+ val |= HISI_PTT_TRACE_CTRL_FILTER_MODE;
+
+ /* Start the Trace */
+ val |= HISI_PTT_TRACE_CTRL_EN;
+ writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
+
+ return 0;
+}
+
+static int hisi_ptt_update_aux(struct hisi_ptt *hisi_ptt, int index, bool stop)
+{
+ struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
+ struct perf_output_handle *handle = &ctrl->handle;
+ struct perf_event *event = handle->event;
+ struct hisi_ptt_pmu_buf *buf;
+ void *addr;
+
+ buf = perf_get_aux(handle);
+ if (!buf || !handle->size)
+ return -EINVAL;
+
+ addr = ctrl->trace_buf[ctrl->buf_index].addr;
+
+ memcpy(buf->base + buf->pos, addr, HISI_PTT_TRACE_BUF_SIZE);
+ memset(addr, 0, HISI_PTT_TRACE_BUF_SIZE);
+ buf->pos += HISI_PTT_TRACE_BUF_SIZE;
+
+ if (stop) {
+ perf_aux_output_end(handle, buf->pos);
+ } else if (buf->length - buf->pos < HISI_PTT_TRACE_BUF_SIZE) {
+ perf_aux_output_skip(handle, buf->length - buf->pos);
+ perf_aux_output_end(handle, buf->pos);
+
+ buf = perf_aux_output_begin(handle, event);
+ if (!buf)
+ return -EINVAL;
+
+ buf->pos = handle->head % buf->length;
+ if (buf->length - buf->pos < HISI_PTT_TRACE_BUF_SIZE) {
+ perf_aux_output_end(handle, 0);
+ return -EINVAL;
+ }
+ }
+
+ return 0;
+}
+
+static irqreturn_t hisi_ptt_isr(int irq, void *context)
+{
+ struct hisi_ptt *hisi_ptt = context;
+ u32 status, buf_idx;
+
+ status = readl(hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
+ buf_idx = ffs(status) - 1;
+
+ /* Clear the interrupt status of buffer @buf_idx */
+ writel(status, hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
+
+ /*
+ * Update the AUX buffer and cache the current buffer index,
+ * as we need to know this and save the data when the trace
+ * is ended out of the interrupt handler. End the trace
+ * if the updating fails.
+ */
+ if (hisi_ptt_update_aux(hisi_ptt, buf_idx, false))
+ hisi_ptt_trace_end(hisi_ptt);
+ else
+ hisi_ptt->trace_ctrl.buf_index = (buf_idx + 1) % HISI_PTT_TRACE_BUF_CNT;
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t hisi_ptt_irq(int irq, void *context)
+{
+ struct hisi_ptt *hisi_ptt = context;
+ u32 status;
+
+ status = readl(hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
+ if (!(status & HISI_PTT_TRACE_INT_STAT_MASK))
+ return IRQ_NONE;
+
+ return IRQ_WAKE_THREAD;
+}
+
+static void hisi_ptt_irq_free_vectors(void *pdev)
+{
+ pci_free_irq_vectors(pdev);
+}
+
+static int hisi_ptt_register_irq(struct hisi_ptt *hisi_ptt)
+{
+ struct pci_dev *pdev = hisi_ptt->pdev;
+ int ret;
+
+ ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSI);
+ if (ret < 0) {
+ pci_err(pdev, "failed to allocate irq vector, ret = %d\n", ret);
+ return ret;
+ }
+
+ ret = devm_add_action_or_reset(&pdev->dev, hisi_ptt_irq_free_vectors, pdev);
+ if (ret < 0)
+ return ret;
+
+ ret = devm_request_threaded_irq(&pdev->dev,
+ pci_irq_vector(pdev, HISI_PTT_TRACE_DMA_IRQ),
+ hisi_ptt_irq, hisi_ptt_isr, 0,
+ DRV_NAME, hisi_ptt);
+ if (ret) {
+ pci_err(pdev, "failed to request irq %d, ret = %d\n",
+ pci_irq_vector(pdev, HISI_PTT_TRACE_DMA_IRQ), ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int hisi_ptt_init_filters(struct pci_dev *pdev, void *data)
+{
+ struct hisi_ptt_filter_desc *filter;
+ struct hisi_ptt *hisi_ptt = data;
+ struct list_head *target_list;
+
+ target_list = pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT ?
+ &hisi_ptt->port_filters : &hisi_ptt->req_filters;
+
+ filter = kzalloc(sizeof(*filter), GFP_KERNEL);
+ if (!filter) {
+ pci_err(hisi_ptt->pdev, "failed to add filter %s\n", pci_name(pdev));
+ return -ENOMEM;
+ }
+
+ filter->pdev = pdev;
+ list_add_tail(&filter->list, target_list);
+
+ /* Update the available port mask */
+ if (pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT)
+ hisi_ptt->port_mask |= hisi_ptt_get_filter_val(pdev);
+
+ return 0;
+}
+
+static void hisi_ptt_release_filters(void *data)
+{
+ struct hisi_ptt_filter_desc *filter, *tfilter;
+ struct hisi_ptt *hisi_ptt = data;
+
+ list_for_each_entry_safe(filter, tfilter, &hisi_ptt->req_filters, list) {
+ list_del(&filter->list);
+ kfree(filter);
+ }
+
+ list_for_each_entry_safe(filter, tfilter, &hisi_ptt->port_filters, list) {
+ list_del(&filter->list);
+ kfree(filter);
+ }
+}
+
+static int hisi_ptt_init_ctrls(struct hisi_ptt *hisi_ptt)
+{
+ struct pci_dev *pdev = hisi_ptt->pdev;
+ struct pci_bus *bus;
+ int ret;
+ u32 reg;
+
+ INIT_LIST_HEAD(&hisi_ptt->port_filters);
+ INIT_LIST_HEAD(&hisi_ptt->req_filters);
+
+ /*
+ * The device range register provides the information about the
+ * root ports which the RCiEP can control and trace. The RCiEP
+ * and the root ports it support are on the same PCIe core, with
+ * same domain number but maybe different bus number. The device
+ * range register will tell us which root ports we can support,
+ * Bit[31:16] indicates the upper BDF numbers of the root port,
+ * while Bit[15:0] indicates the lower.
+ */
+ reg = readl(hisi_ptt->iobase + HISI_PTT_DEVICE_RANGE);
+ hisi_ptt->upper = FIELD_GET(HISI_PTT_DEVICE_RANGE_UPPER, reg);
+ hisi_ptt->lower = FIELD_GET(HISI_PTT_DEVICE_RANGE_LOWER, reg);
+
+ bus = pci_find_bus(pci_domain_nr(pdev->bus), PCI_BUS_NUM(hisi_ptt->upper));
+ if (bus)
+ pci_walk_bus(bus, hisi_ptt_init_filters, hisi_ptt);
+
+ ret = devm_add_action_or_reset(&pdev->dev, hisi_ptt_release_filters, hisi_ptt);
+ if (ret)
+ return ret;
+
+ hisi_ptt->trace_ctrl.default_cpu = cpumask_first(cpumask_of_node(dev_to_node(&pdev->dev)));
+
+ return 0;
+}
+
+#define HISI_PTT_PMU_FILTER_IS_PORT BIT(19)
+#define HISI_PTT_PMU_FILTER_VAL_MASK GENMASK(15, 0)
+#define HISI_PTT_PMU_DIRECTION_MASK GENMASK(23, 20)
+#define HISI_PTT_PMU_TYPE_MASK GENMASK(31, 24)
+#define HISI_PTT_PMU_FORMAT_MASK GENMASK(35, 32)
+
+static ssize_t available_root_port_filters_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct hisi_ptt *hisi_ptt = to_hisi_ptt(dev_get_drvdata(dev));
+ struct hisi_ptt_filter_desc *filter;
+ int pos = 0;
+
+ mutex_lock(&hisi_ptt->mutex);
+ if (list_empty(&hisi_ptt->port_filters)) {
+ pos = sysfs_emit(buf, "\n");
+ goto out;
+ }
+
+ list_for_each_entry(filter, &hisi_ptt->port_filters, list)
+ pos += sysfs_emit_at(buf, pos, "%s 0x%05lx\n",
+ pci_name(filter->pdev),
+ hisi_ptt_get_filter_val(filter->pdev) |
+ HISI_PTT_PMU_FILTER_IS_PORT);
+
+out:
+ mutex_unlock(&hisi_ptt->mutex);
+ return pos;
+}
+static DEVICE_ATTR_ADMIN_RO(available_root_port_filters);
+
+static ssize_t available_requester_filters_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct hisi_ptt *hisi_ptt = to_hisi_ptt(dev_get_drvdata(dev));
+ struct hisi_ptt_filter_desc *filter;
+ int pos = 0;
+
+ mutex_lock(&hisi_ptt->mutex);
+ if (list_empty(&hisi_ptt->req_filters)) {
+ pos = sysfs_emit(buf, "\n");
+ goto out;
+ }
+
+ list_for_each_entry(filter, &hisi_ptt->req_filters, list)
+ pos += sysfs_emit_at(buf, pos, "%s 0x%05x\n",
+ pci_name(filter->pdev),
+ hisi_ptt_get_filter_val(filter->pdev));
+
+out:
+ mutex_unlock(&hisi_ptt->mutex);
+ return pos;
+}
+static DEVICE_ATTR_ADMIN_RO(available_requester_filters);
+
+PMU_FORMAT_ATTR(filter, "config:0-19");
+PMU_FORMAT_ATTR(direction, "config:20-23");
+PMU_FORMAT_ATTR(type, "config:24-31");
+PMU_FORMAT_ATTR(format, "config:32-35");
+
+static struct attribute *hisi_ptt_pmu_format_attrs[] = {
+ &format_attr_filter.attr,
+ &format_attr_direction.attr,
+ &format_attr_type.attr,
+ &format_attr_format.attr,
+ NULL
+};
+
+static struct attribute_group hisi_ptt_pmu_format_group = {
+ .name = "format",
+ .attrs = hisi_ptt_pmu_format_attrs,
+};
+
+static struct attribute *hisi_ptt_pmu_filter_attrs[] = {
+ &dev_attr_available_root_port_filters.attr,
+ &dev_attr_available_requester_filters.attr,
+ NULL
+};
+
+static struct attribute_group hisi_ptt_pmu_filter_group = {
+ .attrs = hisi_ptt_pmu_filter_attrs,
+};
+
+static const struct attribute_group *hisi_ptt_pmu_groups[] = {
+ &hisi_ptt_pmu_format_group,
+ &hisi_ptt_pmu_filter_group,
+ NULL
+};
+
+/*
+ * Check whether the config is valid or not. Some configs are multi-selectable
+ * and can be set simultaneously, while some are single selectable (onehot).
+ * Use this function to check the non-onehot configs while
+ * hisi_ptt_trace_valid_config_onehot() for the onehot ones.
+ */
+static int hisi_ptt_trace_valid_config(u32 val, const u32 *available_list, u32 list_size)
+{
+ int i;
+
+ /* The non-onehot configs cannot be 0. */
+ if (!val)
+ return -EINVAL;
+
+ /*
+ * Walk the available list and clear the valid bits of
+ * the config. If there is any resident bit after the
+ * walk then the config is invalid.
+ */
+ for (i = 0; i < list_size; i++)
+ val &= ~available_list[i];
+
+ return val ? -EINVAL : 0;
+}
+
+static int hisi_ptt_trace_valid_config_onehot(u32 val, const u32 *available_list, u32 list_size)
+{
+ int i;
+
+ for (i = 0; i < list_size; i++)
+ if (val == available_list[i])
+ return 0;
+
+ return -EINVAL;
+}
+
+static int hisi_ptt_trace_init_filter(struct hisi_ptt *hisi_ptt, u64 config)
+{
+ unsigned long val, port_mask = hisi_ptt->port_mask;
+ struct hisi_ptt_filter_desc *filter;
+ int ret = -EINVAL;
+
+ hisi_ptt->trace_ctrl.is_port = FIELD_GET(HISI_PTT_PMU_FILTER_IS_PORT, config);
+ val = FIELD_GET(HISI_PTT_PMU_FILTER_VAL_MASK, config);
+
+ /*
+ * Port filters are defined as bit mask. For port filters, check
+ * the bits in the @val are within the range of hisi_ptt->port_mask
+ * and whether it's empty or not, otherwise user has specified
+ * some unsupported root ports.
+ *
+ * For Requester ID filters, walk the available filter list to see
+ * whether we have one matched.
+ */
+ if (!hisi_ptt->trace_ctrl.is_port) {
+ list_for_each_entry(filter, &hisi_ptt->req_filters, list)
+ if (val == hisi_ptt_get_filter_val(filter->pdev)) {
+ ret = 0;
+ break;
+ }
+ } else if (bitmap_subset(&val, &port_mask, BITS_PER_LONG)) {
+ ret = 0;
+ }
+
+ if (ret)
+ return ret;
+
+ hisi_ptt->trace_ctrl.filter = val;
+ return 0;
+}
+
+static int hisi_ptt_pmu_event_init(struct perf_event *event)
+{
+ /*
+ * The supported value of the direction parameter. See hisi_ptt.rst
+ * documentation for more details.
+ */
+ static const u32 hisi_ptt_trace_available_direction[] = {
+ 0,
+ 1,
+ 2,
+ 3,
+ };
+ /* Different types can be set simultaneously */
+ static const u32 hisi_ptt_trace_available_type[] = {
+ 1, /* posted_request */
+ 2, /* non-posted_request */
+ 4, /* completion */
+ };
+ static const u32 hisi_ptt_trace_availble_format[] = {
+ 0, /* 4DW */
+ 1, /* 8DW */
+ };
+ struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
+ struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
+ int ret;
+ u32 val;
+
+ if (event->attr.type != hisi_ptt->hisi_ptt_pmu.type)
+ return -ENOENT;
+
+ mutex_lock(&hisi_ptt->mutex);
+
+ ret = hisi_ptt_trace_init_filter(hisi_ptt, event->attr.config);
+ if (ret < 0)
+ goto out;
+
+ val = FIELD_GET(HISI_PTT_PMU_DIRECTION_MASK, event->attr.config);
+ ret = hisi_ptt_trace_valid_config_onehot(val, hisi_ptt_trace_available_direction,
+ ARRAY_SIZE(hisi_ptt_trace_available_direction));
+ if (ret < 0)
+ goto out;
+ ctrl->direction = val;
+
+ val = FIELD_GET(HISI_PTT_PMU_TYPE_MASK, event->attr.config);
+ ret = hisi_ptt_trace_valid_config(val, hisi_ptt_trace_available_type,
+ ARRAY_SIZE(hisi_ptt_trace_available_type));
+ if (ret < 0)
+ goto out;
+ ctrl->type = val;
+
+ val = FIELD_GET(HISI_PTT_PMU_FORMAT_MASK, event->attr.config);
+ ret = hisi_ptt_trace_valid_config_onehot(val, hisi_ptt_trace_availble_format,
+ ARRAY_SIZE(hisi_ptt_trace_availble_format));
+ if (ret < 0)
+ goto out;
+ ctrl->format = val;
+
+out:
+ mutex_unlock(&hisi_ptt->mutex);
+ return ret;
+}
+
+static void *hisi_ptt_pmu_setup_aux(struct perf_event *event, void **pages,
+ int nr_pages, bool overwrite)
+{
+ struct hisi_ptt_pmu_buf *buf;
+ struct page **pagelist;
+ int i;
+
+ if (overwrite) {
+ dev_warn(event->pmu->dev, "Overwrite mode is not supported\n");
+ return NULL;
+ }
+
+ /* If the pages size less than buffers, we cannot start trace */
+ if (nr_pages < HISI_PTT_TRACE_TOTAL_BUF_SIZE / PAGE_SIZE)
+ return NULL;
+
+ buf = kzalloc(sizeof(*buf), GFP_KERNEL);
+ if (!buf)
+ return NULL;
+
+ pagelist = kcalloc(nr_pages, sizeof(*pagelist), GFP_KERNEL);
+ if (!pagelist) {
+ kfree(buf);
+ return NULL;
+ }
+
+ for (i = 0; i < nr_pages; i++)
+ pagelist[i] = virt_to_page(pages[i]);
+
+ buf->base = vmap(pagelist, nr_pages, VM_MAP, PAGE_KERNEL);
+ if (!buf->base) {
+ kfree(pagelist);
+ kfree(buf);
+ return NULL;
+ }
+
+ buf->nr_pages = nr_pages;
+ buf->length = nr_pages * PAGE_SIZE;
+ buf->pos = 0;
+
+ kfree(pagelist);
+ return buf;
+}
+
+static void hisi_ptt_pmu_free_aux(void *aux)
+{
+ struct hisi_ptt_pmu_buf *buf = aux;
+
+ vunmap(buf->base);
+ kfree(buf);
+}
+
+static void hisi_ptt_pmu_start(struct perf_event *event, int flags)
+{
+ struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
+ struct perf_output_handle *handle = &hisi_ptt->trace_ctrl.handle;
+ struct hw_perf_event *hwc = &event->hw;
+ struct hisi_ptt_pmu_buf *buf;
+ int cpu = event->cpu;
+ int ret;
+
+ hwc->state = 0;
+ mutex_lock(&hisi_ptt->mutex);
+ if (hisi_ptt->trace_ctrl.started) {
+ pci_dbg(hisi_ptt->pdev, "trace has already started\n");
+ goto stop;
+ }
+
+ if (cpu == -1)
+ cpu = hisi_ptt->trace_ctrl.default_cpu;
+
+ /*
+ * Handle the interrupt on the same cpu which starts the trace to avoid
+ * context mismatch. Otherwise we'll trigger the WARN from the perf
+ * core in event_function_local().
+ */
+ WARN_ON(irq_set_affinity(pci_irq_vector(hisi_ptt->pdev, HISI_PTT_TRACE_DMA_IRQ),
+ cpumask_of(cpu)));
+
+ ret = hisi_ptt_alloc_trace_buf(hisi_ptt);
+ if (ret) {
+ pci_dbg(hisi_ptt->pdev, "alloc trace buf failed, ret = %d\n", ret);
+ goto stop;
+ }
+
+ buf = perf_aux_output_begin(handle, event);
+ if (!buf) {
+ pci_dbg(hisi_ptt->pdev, "aux output begin failed\n");
+ goto stop;
+ }
+
+ buf->pos = handle->head % buf->length;
+
+ ret = hisi_ptt_trace_start(hisi_ptt);
+ if (ret) {
+ pci_dbg(hisi_ptt->pdev, "trace start failed, ret = %d\n", ret);
+ perf_aux_output_end(handle, 0);
+ goto stop;
+ }
+
+ mutex_unlock(&hisi_ptt->mutex);
+ return;
+stop:
+ event->hw.state |= PERF_HES_STOPPED;
+ mutex_unlock(&hisi_ptt->mutex);
+}
+
+static void hisi_ptt_pmu_stop(struct perf_event *event, int flags)
+{
+ struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
+ struct hw_perf_event *hwc = &event->hw;
+
+ if (hwc->state & PERF_HES_STOPPED)
+ return;
+
+ mutex_lock(&hisi_ptt->mutex);
+ if (hisi_ptt->trace_ctrl.started) {
+ hisi_ptt_trace_end(hisi_ptt);
+ WARN(!hisi_ptt_wait_trace_hw_idle(hisi_ptt), "Device is still busy");
+ hisi_ptt_update_aux(hisi_ptt, hisi_ptt->trace_ctrl.buf_index, true);
+ }
+ mutex_unlock(&hisi_ptt->mutex);
+
+ hwc->state |= PERF_HES_STOPPED;
+ perf_event_update_userpage(event);
+ hwc->state |= PERF_HES_UPTODATE;
+}
+
+static int hisi_ptt_pmu_add(struct perf_event *event, int flags)
+{
+ struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
+ struct hw_perf_event *hwc = &event->hw;
+ int cpu = event->cpu;
+
+ /*
+ * Only allow the default cpu to add the event if user doesn't specify
+ * the cpus.
+ */
+ if (cpu == -1 && smp_processor_id() != hisi_ptt->trace_ctrl.default_cpu)
+ return 0;
+
+ hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE;
+
+ if (flags & PERF_EF_START) {
+ hisi_ptt_pmu_start(event, PERF_EF_RELOAD);
+ if (hwc->state & PERF_HES_STOPPED)
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static void hisi_ptt_pmu_del(struct perf_event *event, int flags)
+{
+ hisi_ptt_pmu_stop(event, PERF_EF_UPDATE);
+}
+
+static int hisi_ptt_register_pmu(struct hisi_ptt *hisi_ptt)
+{
+ u16 core_id, sicl_id;
+ char *pmu_name;
+ u32 reg;
+
+ hisi_ptt->hisi_ptt_pmu = (struct pmu) {
+ .module = THIS_MODULE,
+ .capabilities = PERF_PMU_CAP_EXCLUSIVE | PERF_PMU_CAP_ITRACE,
+ .task_ctx_nr = perf_sw_context,
+ .attr_groups = hisi_ptt_pmu_groups,
+ .event_init = hisi_ptt_pmu_event_init,
+ .setup_aux = hisi_ptt_pmu_setup_aux,
+ .free_aux = hisi_ptt_pmu_free_aux,
+ .start = hisi_ptt_pmu_start,
+ .stop = hisi_ptt_pmu_stop,
+ .add = hisi_ptt_pmu_add,
+ .del = hisi_ptt_pmu_del,
+ };
+
+ reg = readl(hisi_ptt->iobase + HISI_PTT_LOCATION);
+ core_id = FIELD_GET(HISI_PTT_CORE_ID, reg);
+ sicl_id = FIELD_GET(HISI_PTT_SICL_ID, reg);
+
+ pmu_name = devm_kasprintf(&hisi_ptt->pdev->dev, GFP_KERNEL, "hisi_ptt%u_%u",
+ sicl_id, core_id);
+ if (!pmu_name)
+ return -ENOMEM;
+
+ return perf_pmu_register(&hisi_ptt->hisi_ptt_pmu, pmu_name, -1);
+}
+
+/*
+ * The DMA of PTT trace can only use direct mapping, due to some
+ * hardware restriction. Check whether there is an IOMMU or the
+ * policy of the IOMMU domain is passthrough, otherwise the trace
+ * cannot work.
+ *
+ * The PTT device is supposed to behind the ARM SMMUv3, which
+ * should have passthrough the device by a quirk.
+ */
+static int hisi_ptt_check_iommu_mapping(struct pci_dev *pdev)
+{
+ struct iommu_domain *iommu_domain;
+
+ iommu_domain = iommu_get_domain_for_dev(&pdev->dev);
+ if (!iommu_domain || iommu_domain->type == IOMMU_DOMAIN_IDENTITY)
+ return 0;
+
+ return -EOPNOTSUPP;
+}
+
+static int hisi_ptt_probe(struct pci_dev *pdev,
+ const struct pci_device_id *id)
+{
+ struct hisi_ptt *hisi_ptt;
+ int ret;
+
+ ret = hisi_ptt_check_iommu_mapping(pdev);
+ if (ret) {
+ pci_err(pdev, "requires direct DMA mappings\n");
+ return ret;
+ }
+
+ hisi_ptt = devm_kzalloc(&pdev->dev, sizeof(*hisi_ptt), GFP_KERNEL);
+ if (!hisi_ptt)
+ return -ENOMEM;
+
+ mutex_init(&hisi_ptt->mutex);
+ hisi_ptt->pdev = pdev;
+ pci_set_drvdata(pdev, hisi_ptt);
+
+ ret = pcim_enable_device(pdev);
+ if (ret) {
+ pci_err(pdev, "failed to enable device, ret = %d\n", ret);
+ return ret;
+ }
+
+ ret = pcim_iomap_regions(pdev, BIT(2), DRV_NAME);
+ if (ret) {
+ pci_err(pdev, "failed to remap io memory, ret = %d\n", ret);
+ return ret;
+ }
+
+ hisi_ptt->iobase = pcim_iomap_table(pdev)[2];
+
+ ret = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(64));
+ if (ret) {
+ pci_err(pdev, "failed to set 64 bit dma mask, ret = %d\n", ret);
+ return ret;
+ }
+
+ pci_set_master(pdev);
+
+ ret = hisi_ptt_register_irq(hisi_ptt);
+ if (ret)
+ return ret;
+
+ ret = hisi_ptt_init_ctrls(hisi_ptt);
+ if (ret) {
+ pci_err(pdev, "failed to init controls, ret = %d\n", ret);
+ return ret;
+ }
+
+ ret = hisi_ptt_register_pmu(hisi_ptt);
+ if (ret) {
+ pci_err(pdev, "failed to register PMU device, ret = %d", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static void hisi_ptt_remove(struct pci_dev *pdev)
+{
+ struct hisi_ptt *hisi_ptt = pci_get_drvdata(pdev);
+
+ /*
+ * We have to manually unregister the PMU device rather than make it
+ * devres managed to keep order that the PMU device's unregistration
+ * is prior to the release of DMA buffers. As the DMA buffers are
+ * devm allocated when necessary which is after the registration of
+ * the PMU device.
+ */
+ perf_pmu_unregister(&hisi_ptt->hisi_ptt_pmu);
+}
+
+static const struct pci_device_id hisi_ptt_id_tbl[] = {
+ { PCI_DEVICE(PCI_VENDOR_ID_HUAWEI, 0xa12e) },
+ { }
+};
+MODULE_DEVICE_TABLE(pci, hisi_ptt_id_tbl);
+
+static struct pci_driver hisi_ptt_driver = {
+ .name = DRV_NAME,
+ .id_table = hisi_ptt_id_tbl,
+ .probe = hisi_ptt_probe,
+ .remove = hisi_ptt_remove,
+};
+module_pci_driver(hisi_ptt_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Yicong Yang <[email protected]>");
+MODULE_DESCRIPTION("Driver for HiSilicon PCIe tune and trace device");
diff --git a/drivers/hwtracing/ptt/hisi_ptt.h b/drivers/hwtracing/ptt/hisi_ptt.h
new file mode 100644
index 000000000000..29b6d6293d6c
--- /dev/null
+++ b/drivers/hwtracing/ptt/hisi_ptt.h
@@ -0,0 +1,166 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Driver for HiSilicon PCIe tune and trace device
+ *
+ * Copyright (c) 2022 HiSilicon Technologies Co., Ltd.
+ * Author: Yicong Yang <[email protected]>
+ */
+
+#ifndef _HISI_PTT_H
+#define _HISI_PTT_H
+
+#include <linux/bits.h>
+#include <linux/list.h>
+#include <linux/mutex.h>
+#include <linux/pci.h>
+#include <linux/perf_event.h>
+#include <linux/types.h>
+
+#define DRV_NAME "hisi_ptt"
+
+/*
+ * The definition of the device registers and register fields.
+ */
+#define HISI_PTT_TRACE_ADDR_SIZE 0x0800
+#define HISI_PTT_TRACE_ADDR_BASE_LO_0 0x0810
+#define HISI_PTT_TRACE_ADDR_BASE_HI_0 0x0814
+#define HISI_PTT_TRACE_ADDR_STRIDE 0x8
+#define HISI_PTT_TRACE_CTRL 0x0850
+#define HISI_PTT_TRACE_CTRL_EN BIT(0)
+#define HISI_PTT_TRACE_CTRL_RST BIT(1)
+#define HISI_PTT_TRACE_CTRL_RXTX_SEL GENMASK(3, 2)
+#define HISI_PTT_TRACE_CTRL_TYPE_SEL GENMASK(7, 4)
+#define HISI_PTT_TRACE_CTRL_DATA_FORMAT BIT(14)
+#define HISI_PTT_TRACE_CTRL_FILTER_MODE BIT(15)
+#define HISI_PTT_TRACE_CTRL_TARGET_SEL GENMASK(31, 16)
+#define HISI_PTT_TRACE_INT_STAT 0x0890
+#define HISI_PTT_TRACE_INT_STAT_MASK GENMASK(3, 0)
+#define HISI_PTT_TRACE_INT_MASK 0x0894
+#define HISI_PTT_TRACE_WR_STS 0x08a0
+#define HISI_PTT_TRACE_WR_STS_WRITE GENMASK(27, 0)
+#define HISI_PTT_TRACE_WR_STS_BUFFER GENMASK(29, 28)
+#define HISI_PTT_TRACE_STS 0x08b0
+#define HISI_PTT_TRACE_IDLE BIT(0)
+#define HISI_PTT_DEVICE_RANGE 0x0fe0
+#define HISI_PTT_DEVICE_RANGE_UPPER GENMASK(31, 16)
+#define HISI_PTT_DEVICE_RANGE_LOWER GENMASK(15, 0)
+#define HISI_PTT_LOCATION 0x0fe8
+#define HISI_PTT_CORE_ID GENMASK(15, 0)
+#define HISI_PTT_SICL_ID GENMASK(31, 16)
+
+/* Parameters of PTT trace DMA part. */
+#define HISI_PTT_TRACE_DMA_IRQ 0
+#define HISI_PTT_TRACE_BUF_CNT 4
+#define HISI_PTT_TRACE_BUF_SIZE SZ_4M
+#define HISI_PTT_TRACE_TOTAL_BUF_SIZE (HISI_PTT_TRACE_BUF_SIZE * \
+ HISI_PTT_TRACE_BUF_CNT)
+/* Wait time for hardware DMA to reset */
+#define HISI_PTT_RESET_TIMEOUT_US 10UL
+#define HISI_PTT_RESET_POLL_INTERVAL_US 1UL
+/* Poll timeout and interval for waiting hardware work to finish */
+#define HISI_PTT_WAIT_TRACE_TIMEOUT_US 100UL
+#define HISI_PTT_WAIT_POLL_INTERVAL_US 10UL
+
+#define HISI_PCIE_CORE_PORT_ID(devfn) (PCI_FUNC(devfn) << 1)
+
+/**
+ * struct hisi_ptt_dma_buffer - describe a single trace buffer of PTT trace.
+ * The detail of the data format is described
+ * in the documentation of PTT device.
+ * @dma: DMA address of this buffer visible to the device
+ * @addr: virtual address of this buffer visible to the cpu
+ */
+struct hisi_ptt_dma_buffer {
+ dma_addr_t dma;
+ void *addr;
+};
+
+/**
+ * struct hisi_ptt_trace_ctrl - control and status of PTT trace
+ * @trace_buf: array of the trace buffers for holding the trace data.
+ * the length will be HISI_PTT_TRACE_BUF_CNT.
+ * @handle: perf output handle of current trace session
+ * @default_cpu: default cpu to start the trace session
+ * @buf_index: the index of current using trace buffer
+ * @started: current trace status, true for started
+ * @is_port: whether we're tracing root port or not
+ * @direction: direction of the TLP headers to trace
+ * @filter: filter value for tracing the TLP headers
+ * @format: format of the TLP headers to trace
+ * @type: type of the TLP headers to trace
+ */
+struct hisi_ptt_trace_ctrl {
+ struct hisi_ptt_dma_buffer *trace_buf;
+ struct perf_output_handle handle;
+ int default_cpu;
+ u32 buf_index;
+ bool started;
+ bool is_port;
+ u32 direction:2;
+ u32 filter:16;
+ u32 format:1;
+ u32 type:4;
+};
+
+/**
+ * struct hisi_ptt_filter_desc - descriptor of the PTT trace filter
+ * @list: entry of this descriptor in the filter list
+ * @pdev: pci_dev related to this filter
+ */
+struct hisi_ptt_filter_desc {
+ struct list_head list;
+ struct pci_dev *pdev;
+};
+
+
+/**
+ * struct hisi_ptt_pmu_buf - descriptor of the AUX buffer of PTT trace
+ * @length: size of the AUX buffer
+ * @nr_pages: number of pages of the AUX buffer
+ * @base: start address of AUX buffer
+ * @pos: position in the AUX buffer to commit traced data
+ */
+struct hisi_ptt_pmu_buf {
+ size_t length;
+ int nr_pages;
+ void *base;
+ long pos;
+};
+
+/**
+ * struct hisi_ptt - per PTT device data
+ * @trace_ctrl: the control information of PTT trace
+ * @hisi_ptt_pmu: the pum device of trace
+ * @iobase: base IO address of the device
+ * @pdev: pci_dev of this PTT device
+ * @mutex: mutex to protect the filter list and serialize the perf process.
+ * @upper: the upper BDF range of the PCI devices managed by this PTT device
+ * @lower: the lower BDF range of the PCI devices managed by this PTT device
+ * @port_filters: the filter list of root ports
+ * @req_filters: the filter list of requester ID
+ * @port_mask: port mask of the managed root ports
+ */
+struct hisi_ptt {
+ struct hisi_ptt_trace_ctrl trace_ctrl;
+ struct pmu hisi_ptt_pmu;
+ void __iomem *iobase;
+ struct pci_dev *pdev;
+ struct mutex mutex;
+ u32 upper;
+ u32 lower;
+
+ /*
+ * The trace TLP headers can either be filtered by certain
+ * root port, or by the requester ID. Organize the filters
+ * by @port_filters and @req_filters here. The mask of all
+ * the valid ports is also cached for doing sanity check
+ * of user input.
+ */
+ struct list_head port_filters;
+ struct list_head req_filters;
+ u16 port_mask;
+};
+
+#define to_hisi_ptt(pmu) container_of(pmu, struct hisi_ptt, hisi_ptt_pmu)
+
+#endif /* _HISI_PTT_H */
--
2.24.0
On 07/04/2022 13:58, Yicong Yang wrote:
> HiSilicon PCIe tune and trace device(PTT) is a PCIe Root Complex integrated
> Endpoint(RCiEP) device, providing the capability to dynamically monitor and
> tune the PCIe traffic, and trace the TLP headers.
>
> Add the driver for the device to enable the trace function. Register PMU
> device of PTT trace, then users can use trace through perf command. The
> driver makes use of perf AUX trace and support following events to
"The driver makes use of perf AUX trace function and supports the
following events to .."
> configure the trace:
>
> - filter: select Root port or Endpoint to trace
> - type: select the type of traced TLP headers
> - direction: select the direction of traced TLP headers
> - format: select the data format of the traced TLP headers
>
> This patch adds the driver part of PTT trace. The perf command support of
> PTT trace is added in the following patch.
I would not mention "following patch" and the like. Just have "initially
add a basic driver"
>
> Signed-off-by: Yicong Yang <[email protected]>
> Reviewed-by: Jonathan Cameron <[email protected]>
> ---
> drivers/Makefile | 1 +
> drivers/hwtracing/Kconfig | 2 +
> drivers/hwtracing/ptt/Kconfig | 12 +
> drivers/hwtracing/ptt/Makefile | 2 +
> drivers/hwtracing/ptt/hisi_ptt.c | 874 +++++++++++++++++++++++++++++++
> drivers/hwtracing/ptt/hisi_ptt.h | 166 ++++++
> 6 files changed, 1057 insertions(+)
> create mode 100644 drivers/hwtracing/ptt/Kconfig
> create mode 100644 drivers/hwtracing/ptt/Makefile
> create mode 100644 drivers/hwtracing/ptt/hisi_ptt.c
> create mode 100644 drivers/hwtracing/ptt/hisi_ptt.h
>
> diff --git a/drivers/Makefile b/drivers/Makefile
> index 020780b6b4d2..662d50599467 100644
> --- a/drivers/Makefile
> +++ b/drivers/Makefile
> @@ -175,6 +175,7 @@ obj-$(CONFIG_USB4) += thunderbolt/
> obj-$(CONFIG_CORESIGHT) += hwtracing/coresight/
> obj-y += hwtracing/intel_th/
> obj-$(CONFIG_STM) += hwtracing/stm/
> +obj-$(CONFIG_HISI_PTT) += hwtracing/ptt/
> obj-$(CONFIG_ANDROID) += android/
> obj-$(CONFIG_NVMEM) += nvmem/
> obj-$(CONFIG_FPGA) += fpga/
> diff --git a/drivers/hwtracing/Kconfig b/drivers/hwtracing/Kconfig
> index 13085835a636..911ee977103c 100644
> --- a/drivers/hwtracing/Kconfig
> +++ b/drivers/hwtracing/Kconfig
> @@ -5,4 +5,6 @@ source "drivers/hwtracing/stm/Kconfig"
>
> source "drivers/hwtracing/intel_th/Kconfig"
>
> +source "drivers/hwtracing/ptt/Kconfig"
> +
> endmenu
> diff --git a/drivers/hwtracing/ptt/Kconfig b/drivers/hwtracing/ptt/Kconfig
> new file mode 100644
> index 000000000000..8902a6f27563
> --- /dev/null
> +++ b/drivers/hwtracing/ptt/Kconfig
> @@ -0,0 +1,12 @@
> +# SPDX-License-Identifier: GPL-2.0-only
> +config HISI_PTT
> + tristate "HiSilicon PCIe Tune and Trace Device"
> + depends on ARM64 || (COMPILE_TEST && 64BIT)
> + depends on PCI && HAS_DMA && HAS_IOMEM && PERF_EVENTS
> + help
> + HiSilicon PCIe Tune and Trace Device exists as a PCIe RCiEP
> + device, and it provides support for PCIe traffic tuning and
> + tracing TLP headers to the memory.
> +
> + This driver can also be built as a module. If so, the module
> + will be called hisi_ptt.
> diff --git a/drivers/hwtracing/ptt/Makefile b/drivers/hwtracing/ptt/Makefile
> new file mode 100644
> index 000000000000..908c09a98161
> --- /dev/null
> +++ b/drivers/hwtracing/ptt/Makefile
> @@ -0,0 +1,2 @@
> +# SPDX-License-Identifier: GPL-2.0
> +obj-$(CONFIG_HISI_PTT) += hisi_ptt.o
> diff --git a/drivers/hwtracing/ptt/hisi_ptt.c b/drivers/hwtracing/ptt/hisi_ptt.c
> new file mode 100644
> index 000000000000..242b41870380
> --- /dev/null
> +++ b/drivers/hwtracing/ptt/hisi_ptt.c
> @@ -0,0 +1,874 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Driver for HiSilicon PCIe tune and trace device
> + *
> + * Copyright (c) 2022 HiSilicon Technologies Co., Ltd.
> + * Author: Yicong Yang <[email protected]>
> + */
> +
> +#include <linux/bitfield.h>
> +#include <linux/bitops.h>
> +#include <linux/delay.h>
> +#include <linux/dma-iommu.h>
> +#include <linux/dma-mapping.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/iommu.h>
> +#include <linux/iopoll.h>
> +#include <linux/module.h>
> +#include <linux/sysfs.h>
> +#include <linux/vmalloc.h>
> +
> +#include "hisi_ptt.h"
> +
> +static u16 hisi_ptt_get_filter_val(struct pci_dev *pdev)
> +{
> + if (pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT)
> + return BIT(HISI_PCIE_CORE_PORT_ID(PCI_SLOT(pdev->devfn)));
> +
> + return PCI_DEVID(pdev->bus->number, pdev->devfn);
> +}
> +
> +static bool hisi_ptt_wait_trace_hw_idle(struct hisi_ptt *hisi_ptt)
> +{
> + u32 val;
> +
> + return !readl_poll_timeout_atomic(hisi_ptt->iobase + HISI_PTT_TRACE_STS,
> + val, val & HISI_PTT_TRACE_IDLE,
> + HISI_PTT_WAIT_POLL_INTERVAL_US,
> + HISI_PTT_WAIT_TRACE_TIMEOUT_US);
> +}
> +
> +static bool hisi_ptt_wait_dma_reset_done(struct hisi_ptt *hisi_ptt)
> +{
> + u32 val;
> +
> + return !readl_poll_timeout_atomic(hisi_ptt->iobase + HISI_PTT_TRACE_WR_STS,
> + val, !val, HISI_PTT_RESET_POLL_INTERVAL_US,
> + HISI_PTT_RESET_TIMEOUT_US);
> +}
> +
> +static void hisi_ptt_free_trace_buf(struct hisi_ptt *hisi_ptt)
> +{
> + struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
> + struct device *dev = &hisi_ptt->pdev->dev;
> + int i;
> +
> + if (!ctrl->trace_buf)
> + return;
> +
> + for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; i++) {
> + if (ctrl->trace_buf[i].addr)
> + dmam_free_coherent(dev, HISI_PTT_TRACE_BUF_SIZE,
> + ctrl->trace_buf[i].addr,
> + ctrl->trace_buf[i].dma);
> + }
> +
> + devm_kfree(dev, ctrl->trace_buf);
> + ctrl->trace_buf = NULL;
> +}
> +
> +static int hisi_ptt_alloc_trace_buf(struct hisi_ptt *hisi_ptt)
> +{
> + struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
> + struct device *dev = &hisi_ptt->pdev->dev;
> + int i;
> +
> + hisi_ptt->trace_ctrl.buf_index = 0;
> +
> + /* If the trace buffer has already been allocated, zero it. */
I am not sure why this is not called from the probe
> + if (ctrl->trace_buf) {
> + for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; i++)
> + memset(ctrl->trace_buf[i].addr, 0, HISI_PTT_TRACE_BUF_SIZE);
> + return 0;
> + }
> +
> + ctrl->trace_buf = devm_kcalloc(dev, HISI_PTT_TRACE_BUF_CNT,
> + sizeof(struct hisi_ptt_dma_buffer), GFP_KERNEL);
sizeof(*ctrl->trace_buf) may be better
> + if (!ctrl->trace_buf)
> + return -ENOMEM;
> +
> + for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; ++i) {
> + ctrl->trace_buf[i].addr = dmam_alloc_coherent(dev, HISI_PTT_TRACE_BUF_SIZE,
> + &ctrl->trace_buf[i].dma,
> + GFP_KERNEL);
> + if (!ctrl->trace_buf[i].addr) {
> + hisi_ptt_free_trace_buf(hisi_ptt);
> + return -ENOMEM;
> + }
> + }
> +
> + return 0;
> +}
> +
> +static void hisi_ptt_trace_end(struct hisi_ptt *hisi_ptt)
> +{
> + writel(0, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
> + hisi_ptt->trace_ctrl.started = false;
> +}
> +
> +static int hisi_ptt_trace_start(struct hisi_ptt *hisi_ptt)
> +{
> + struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
> + u32 val;
> + int i;
> +
> + /* Check device idle before start trace */
> + if (!hisi_ptt_wait_trace_hw_idle(hisi_ptt)) {
> + pci_err(hisi_ptt->pdev, "Failed to start trace, the device is still busy\n");
> + return -EBUSY;
> + }
> +
> + ctrl->started = true;
> +
> + /* Reset the DMA before start tracing */
> + val = readl(hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
> + val |= HISI_PTT_TRACE_CTRL_RST;
> + writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
> +
> + hisi_ptt_wait_dma_reset_done(hisi_ptt);
> +
> + val = readl(hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
> + val &= ~HISI_PTT_TRACE_CTRL_RST;
> + writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
> +
> + /* Clear the interrupt status */
> + writel(HISI_PTT_TRACE_INT_STAT_MASK, hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
> + writel(0, hisi_ptt->iobase + HISI_PTT_TRACE_INT_MASK);
> +
> + /* Configure the trace DMA buffer */
I am not sure why this sort of thing is done outside probing
> + for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; i++) {
> + writel(lower_32_bits(ctrl->trace_buf[i].dma),
> + hisi_ptt->iobase + HISI_PTT_TRACE_ADDR_BASE_LO_0 +
> + i * HISI_PTT_TRACE_ADDR_STRIDE);
> + writel(upper_32_bits(ctrl->trace_buf[i].dma),
> + hisi_ptt->iobase + HISI_PTT_TRACE_ADDR_BASE_HI_0 +
> + i * HISI_PTT_TRACE_ADDR_STRIDE);
> + }
> + writel(HISI_PTT_TRACE_BUF_SIZE, hisi_ptt->iobase + HISI_PTT_TRACE_ADDR_SIZE);
> +
> + /* Set the trace control register */
> + val = FIELD_PREP(HISI_PTT_TRACE_CTRL_TYPE_SEL, ctrl->type);
> + val |= FIELD_PREP(HISI_PTT_TRACE_CTRL_RXTX_SEL, ctrl->direction);
> + val |= FIELD_PREP(HISI_PTT_TRACE_CTRL_DATA_FORMAT, ctrl->format);
> + val |= FIELD_PREP(HISI_PTT_TRACE_CTRL_TARGET_SEL, hisi_ptt->trace_ctrl.filter);
> + if (!hisi_ptt->trace_ctrl.is_port)
> + val |= HISI_PTT_TRACE_CTRL_FILTER_MODE;
> +
> + /* Start the Trace */
> + val |= HISI_PTT_TRACE_CTRL_EN;
> + writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
> +
> + return 0;
> +}
> +
> +static int hisi_ptt_update_aux(struct hisi_ptt *hisi_ptt, int index, bool stop)
> +{
> + struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
> + struct perf_output_handle *handle = &ctrl->handle;
> + struct perf_event *event = handle->event;
> + struct hisi_ptt_pmu_buf *buf;
> + void *addr;
> +
> + buf = perf_get_aux(handle);
> + if (!buf || !handle->size)
> + return -EINVAL;
> +
> + addr = ctrl->trace_buf[ctrl->buf_index].addr;
> +
> + memcpy(buf->base + buf->pos, addr, HISI_PTT_TRACE_BUF_SIZE);
> + memset(addr, 0, HISI_PTT_TRACE_BUF_SIZE);
> + buf->pos += HISI_PTT_TRACE_BUF_SIZE;
> +
> + if (stop) {
> + perf_aux_output_end(handle, buf->pos);
> + } else if (buf->length - buf->pos < HISI_PTT_TRACE_BUF_SIZE) {
> + perf_aux_output_skip(handle, buf->length - buf->pos);
> + perf_aux_output_end(handle, buf->pos);
> +
> + buf = perf_aux_output_begin(handle, event);
> + if (!buf)
> + return -EINVAL;
> +
> + buf->pos = handle->head % buf->length;
> + if (buf->length - buf->pos < HISI_PTT_TRACE_BUF_SIZE) {
> + perf_aux_output_end(handle, 0);
> + return -EINVAL;
> + }
> + }
> +
> + return 0;
> +}
> +
> +static irqreturn_t hisi_ptt_isr(int irq, void *context)
> +{
> + struct hisi_ptt *hisi_ptt = context;
> + u32 status, buf_idx;
> +
> + status = readl(hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
> + buf_idx = ffs(status) - 1;
> +
> + /* Clear the interrupt status of buffer @buf_idx */
> + writel(status, hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
> +
> + /*
> + * Update the AUX buffer and cache the current buffer index,
> + * as we need to know this and save the data when the trace
> + * is ended out of the interrupt handler. End the trace
> + * if the updating fails.
> + */
> + if (hisi_ptt_update_aux(hisi_ptt, buf_idx, false))
> + hisi_ptt_trace_end(hisi_ptt);
> + else
> + hisi_ptt->trace_ctrl.buf_index = (buf_idx + 1) % HISI_PTT_TRACE_BUF_CNT;
> +
> + return IRQ_HANDLED;
> +}
> +
> +static irqreturn_t hisi_ptt_irq(int irq, void *context)
> +{
> + struct hisi_ptt *hisi_ptt = context;
> + u32 status;
> +
> + status = readl(hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
> + if (!(status & HISI_PTT_TRACE_INT_STAT_MASK))
> + return IRQ_NONE;
> +
> + return IRQ_WAKE_THREAD;
> +}
> +
> +static void hisi_ptt_irq_free_vectors(void *pdev)
> +{
> + pci_free_irq_vectors(pdev);
> +}
> +
> +static int hisi_ptt_register_irq(struct hisi_ptt *hisi_ptt)
> +{
> + struct pci_dev *pdev = hisi_ptt->pdev;
> + int ret;
> +
> + ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSI);
> + if (ret < 0) {
> + pci_err(pdev, "failed to allocate irq vector, ret = %d\n", ret);
> + return ret;
> + }
> +
> + ret = devm_add_action_or_reset(&pdev->dev, hisi_ptt_irq_free_vectors, pdev);
> + if (ret < 0)
> + return ret;
> +
> + ret = devm_request_threaded_irq(&pdev->dev,
> + pci_irq_vector(pdev, HISI_PTT_TRACE_DMA_IRQ),
> + hisi_ptt_irq, hisi_ptt_isr, 0,
> + DRV_NAME, hisi_ptt);
> + if (ret) {
> + pci_err(pdev, "failed to request irq %d, ret = %d\n",
> + pci_irq_vector(pdev, HISI_PTT_TRACE_DMA_IRQ), ret);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int hisi_ptt_init_filters(struct pci_dev *pdev, void *data)
> +{
> + struct hisi_ptt_filter_desc *filter;
> + struct hisi_ptt *hisi_ptt = data;
> + struct list_head *target_list;
> +
> + target_list = pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT ?
> + &hisi_ptt->port_filters : &hisi_ptt->req_filters;
> +
> + filter = kzalloc(sizeof(*filter), GFP_KERNEL);
> + if (!filter) {
> + pci_err(hisi_ptt->pdev, "failed to add filter %s\n", pci_name(pdev));
> + return -ENOMEM;
> + }
> +
> + filter->pdev = pdev;
> + list_add_tail(&filter->list, target_list);
> +
> + /* Update the available port mask */
> + if (pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT)
> + hisi_ptt->port_mask |= hisi_ptt_get_filter_val(pdev);
> +
> + return 0;
> +}
> +
> +static void hisi_ptt_release_filters(void *data)
> +{
> + struct hisi_ptt_filter_desc *filter, *tfilter;
> + struct hisi_ptt *hisi_ptt = data;
> +
> + list_for_each_entry_safe(filter, tfilter, &hisi_ptt->req_filters, list) {
> + list_del(&filter->list);
> + kfree(filter);
> + }
> +
> + list_for_each_entry_safe(filter, tfilter, &hisi_ptt->port_filters, list) {
> + list_del(&filter->list);
> + kfree(filter);
> + }
> +}
> +
> +static int hisi_ptt_init_ctrls(struct hisi_ptt *hisi_ptt)
> +{
> + struct pci_dev *pdev = hisi_ptt->pdev;
> + struct pci_bus *bus;
> + int ret;
> + u32 reg;
> +
> + INIT_LIST_HEAD(&hisi_ptt->port_filters);
> + INIT_LIST_HEAD(&hisi_ptt->req_filters);
> +
> + /*
> + * The device range register provides the information about the
> + * root ports which the RCiEP can control and trace. The RCiEP
> + * and the root ports it support are on the same PCIe core, with
> + * same domain number but maybe different bus number. The device
> + * range register will tell us which root ports we can support,
> + * Bit[31:16] indicates the upper BDF numbers of the root port,
> + * while Bit[15:0] indicates the lower.
> + */
> + reg = readl(hisi_ptt->iobase + HISI_PTT_DEVICE_RANGE);
> + hisi_ptt->upper = FIELD_GET(HISI_PTT_DEVICE_RANGE_UPPER, reg);
> + hisi_ptt->lower = FIELD_GET(HISI_PTT_DEVICE_RANGE_LOWER, reg);
> +
> + bus = pci_find_bus(pci_domain_nr(pdev->bus), PCI_BUS_NUM(hisi_ptt->upper));
> + if (bus)
> + pci_walk_bus(bus, hisi_ptt_init_filters, hisi_ptt);
> +
> + ret = devm_add_action_or_reset(&pdev->dev, hisi_ptt_release_filters, hisi_ptt);
> + if (ret)
> + return ret;
> +
> + hisi_ptt->trace_ctrl.default_cpu = cpumask_first(cpumask_of_node(dev_to_node(&pdev->dev)));
> +
> + return 0;
> +}
> +
> +#define HISI_PTT_PMU_FILTER_IS_PORT BIT(19)
> +#define HISI_PTT_PMU_FILTER_VAL_MASK GENMASK(15, 0)
> +#define HISI_PTT_PMU_DIRECTION_MASK GENMASK(23, 20)
> +#define HISI_PTT_PMU_TYPE_MASK GENMASK(31, 24)
> +#define HISI_PTT_PMU_FORMAT_MASK GENMASK(35, 32)
> +
> +static ssize_t available_root_port_filters_show(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + struct hisi_ptt *hisi_ptt = to_hisi_ptt(dev_get_drvdata(dev));
> + struct hisi_ptt_filter_desc *filter;
> + int pos = 0;
> +
> + mutex_lock(&hisi_ptt->mutex);
> + if (list_empty(&hisi_ptt->port_filters)) {
> + pos = sysfs_emit(buf, "\n");
> + goto out;
> + }
> +
> + list_for_each_entry(filter, &hisi_ptt->port_filters, list)
> + pos += sysfs_emit_at(buf, pos, "%s 0x%05lx\n",
\t can be used for a formatting tab
> + pci_name(filter->pdev),
> + hisi_ptt_get_filter_val(filter->pdev) |
> + HISI_PTT_PMU_FILTER_IS_PORT);
> +
> +out:
> + mutex_unlock(&hisi_ptt->mutex);
> + return pos;
> +}
> +static DEVICE_ATTR_ADMIN_RO(available_root_port_filters);
> +
> +static ssize_t available_requester_filters_show(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + struct hisi_ptt *hisi_ptt = to_hisi_ptt(dev_get_drvdata(dev));
> + struct hisi_ptt_filter_desc *filter;
> + int pos = 0;
> +
> + mutex_lock(&hisi_ptt->mutex);
> + if (list_empty(&hisi_ptt->req_filters)) {
> + pos = sysfs_emit(buf, "\n");
> + goto out;
> + }
> +
> + list_for_each_entry(filter, &hisi_ptt->req_filters, list)
> + pos += sysfs_emit_at(buf, pos, "%s 0x%05x\n",
> + pci_name(filter->pdev),
> + hisi_ptt_get_filter_val(filter->pdev));
> +
> +out:
> + mutex_unlock(&hisi_ptt->mutex);
> + return pos;
> +}
> +static DEVICE_ATTR_ADMIN_RO(available_requester_filters);
> +
> +PMU_FORMAT_ATTR(filter, "config:0-19");
> +PMU_FORMAT_ATTR(direction, "config:20-23");
> +PMU_FORMAT_ATTR(type, "config:24-31");
> +PMU_FORMAT_ATTR(format, "config:32-35");
> +
> +static struct attribute *hisi_ptt_pmu_format_attrs[] = {
> + &format_attr_filter.attr,
> + &format_attr_direction.attr,
> + &format_attr_type.attr,
> + &format_attr_format.attr,
> + NULL
> +};
> +
> +static struct attribute_group hisi_ptt_pmu_format_group = {
> + .name = "format",
> + .attrs = hisi_ptt_pmu_format_attrs,
> +};
> +
> +static struct attribute *hisi_ptt_pmu_filter_attrs[] = {
> + &dev_attr_available_root_port_filters.attr,
> + &dev_attr_available_requester_filters.attr,
> + NULL
> +};
> +
> +static struct attribute_group hisi_ptt_pmu_filter_group = {
> + .attrs = hisi_ptt_pmu_filter_attrs,
> +};
> +
> +static const struct attribute_group *hisi_ptt_pmu_groups[] = {
> + &hisi_ptt_pmu_format_group,
> + &hisi_ptt_pmu_filter_group,
> + NULL
> +};
> +
> +/*
> + * Check whether the config is valid or not. Some configs are multi-selectable
> + * and can be set simultaneously, while some are single selectable (onehot).
> + * Use this function to check the non-onehot configs while
> + * hisi_ptt_trace_valid_config_onehot() for the onehot ones.
> + */
> +static int hisi_ptt_trace_valid_config(u32 val, const u32 *available_list, u32 list_size)
> +{
> + int i;
> +
> + /* The non-onehot configs cannot be 0. */
> + if (!val)
> + return -EINVAL;
> +
> + /*
> + * Walk the available list and clear the valid bits of
> + * the config. If there is any resident bit after the
> + * walk then the config is invalid.
> + */
> + for (i = 0; i < list_size; i++)
> + val &= ~available_list[i];
> +
> + return val ? -EINVAL : 0;
> +}
> +
> +static int hisi_ptt_trace_valid_config_onehot(u32 val, const u32 *available_list, u32 list_size)
line too long
> +{
> + int i;
> +
> + for (i = 0; i < list_size; i++)
> + if (val == available_list[i])
> + return 0;
> +
> + return -EINVAL;
> +}
> +
> +static int hisi_ptt_trace_init_filter(struct hisi_ptt *hisi_ptt, u64 config)
> +{
> + unsigned long val, port_mask = hisi_ptt->port_mask;
> + struct hisi_ptt_filter_desc *filter;
> + int ret = -EINVAL;
> +
> + hisi_ptt->trace_ctrl.is_port = FIELD_GET(HISI_PTT_PMU_FILTER_IS_PORT, config);
> + val = FIELD_GET(HISI_PTT_PMU_FILTER_VAL_MASK, config);
> +
> + /*
> + * Port filters are defined as bit mask. For port filters, check
> + * the bits in the @val are within the range of hisi_ptt->port_mask
> + * and whether it's empty or not, otherwise user has specified
> + * some unsupported root ports.
> + *
> + * For Requester ID filters, walk the available filter list to see
> + * whether we have one matched.
> + */
> + if (!hisi_ptt->trace_ctrl.is_port) {
> + list_for_each_entry(filter, &hisi_ptt->req_filters, list)
use {} for this as well. the formatting looks strange
> + if (val == hisi_ptt_get_filter_val(filter->pdev)) {
> + ret = 0;
> + break;
> + }
> + } else if (bitmap_subset(&val, &port_mask, BITS_PER_LONG)) {
> + ret = 0;
> + }
> +
> + if (ret)
> + return ret;
> +
> + hisi_ptt->trace_ctrl.filter = val;
> + return 0;
> +}
> +
> +static int hisi_ptt_pmu_event_init(struct perf_event *event)
> +{
> + /*
> + * The supported value of the direction parameter. See hisi_ptt.rst
> + * documentation for more details.
> + */
> + static const u32 hisi_ptt_trace_available_direction[] = {
> + 0,
> + 1,
> + 2,
> + 3,
> + };
> + /* Different types can be set simultaneously */
> + static const u32 hisi_ptt_trace_available_type[] = {
> + 1, /* posted_request */
> + 2, /* non-posted_request */
> + 4, /* completion */
> + };
> + static const u32 hisi_ptt_trace_availble_format[] = {
> + 0, /* 4DW */
> + 1, /* 8DW */
> + };
> + struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
> + struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
> + int ret;
> + u32 val;
> +
> + if (event->attr.type != hisi_ptt->hisi_ptt_pmu.type)
> + return -ENOENT;
> +
> + mutex_lock(&hisi_ptt->mutex);
> +
> + ret = hisi_ptt_trace_init_filter(hisi_ptt, event->attr.config);
> + if (ret < 0)
> + goto out;
> +
> + val = FIELD_GET(HISI_PTT_PMU_DIRECTION_MASK, event->attr.config);
> + ret = hisi_ptt_trace_valid_config_onehot(val, hisi_ptt_trace_available_direction,
how about put all those arrays in hisi_ptt_trace_valid_config_onehot()
and pass some flag to say which array you want to use? Or something like
that. Passing the arrays in this fashion is messy
> + ARRAY_SIZE(hisi_ptt_trace_available_direction));
> + if (ret < 0)
> + goto out;
> + ctrl->direction = val;
> +
> + val = FIELD_GET(HISI_PTT_PMU_TYPE_MASK, event->attr.config);
> + ret = hisi_ptt_trace_valid_config(val, hisi_ptt_trace_available_type,
> + ARRAY_SIZE(hisi_ptt_trace_available_type));
> + if (ret < 0)
> + goto out;
> + ctrl->type = val;
> +
> + val = FIELD_GET(HISI_PTT_PMU_FORMAT_MASK, event->attr.config);
> + ret = hisi_ptt_trace_valid_config_onehot(val, hisi_ptt_trace_availble_format,
> + ARRAY_SIZE(hisi_ptt_trace_availble_format));
> + if (ret < 0)
> + goto out;
> + ctrl->format = val;
> +
> +out:
> + mutex_unlock(&hisi_ptt->mutex);
> + return ret;
> +}
> +
> +static void *hisi_ptt_pmu_setup_aux(struct perf_event *event, void **pages,
> + int nr_pages, bool overwrite)
> +{
> + struct hisi_ptt_pmu_buf *buf;
> + struct page **pagelist;
> + int i;
> +
> + if (overwrite) {
> + dev_warn(event->pmu->dev, "Overwrite mode is not supported\n");
> + return NULL;
> + }
> +
> + /* If the pages size less than buffers, we cannot start trace */
> + if (nr_pages < HISI_PTT_TRACE_TOTAL_BUF_SIZE / PAGE_SIZE)
> + return NULL;
> +
> + buf = kzalloc(sizeof(*buf), GFP_KERNEL);
> + if (!buf)
> + return NULL;
> +
> + pagelist = kcalloc(nr_pages, sizeof(*pagelist), GFP_KERNEL);
> + if (!pagelist) {
> + kfree(buf);
> + return NULL;
> + }
> +
> + for (i = 0; i < nr_pages; i++)
> + pagelist[i] = virt_to_page(pages[i]);
> +
> + buf->base = vmap(pagelist, nr_pages, VM_MAP, PAGE_KERNEL);
> + if (!buf->base) {
> + kfree(pagelist);
> + kfree(buf);
> + return NULL;
> + }
> +
> + buf->nr_pages = nr_pages;
> + buf->length = nr_pages * PAGE_SIZE;
> + buf->pos = 0;
> +
> + kfree(pagelist);
> + return buf;
> +}
> +
> +static void hisi_ptt_pmu_free_aux(void *aux)
> +{
> + struct hisi_ptt_pmu_buf *buf = aux;
> +
> + vunmap(buf->base);
> + kfree(buf);
> +}
> +
> +static void hisi_ptt_pmu_start(struct perf_event *event, int flags)
> +{
> + struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
> + struct perf_output_handle *handle = &hisi_ptt->trace_ctrl.handle;
> + struct hw_perf_event *hwc = &event->hw;
> + struct hisi_ptt_pmu_buf *buf;
> + int cpu = event->cpu;
> + int ret;
> +
> + hwc->state = 0;
> + mutex_lock(&hisi_ptt->mutex);
> + if (hisi_ptt->trace_ctrl.started) {
> + pci_dbg(hisi_ptt->pdev, "trace has already started\n");
doesn't perf core guard against this sort of thing?
> + goto stop;
> + }
> +
> + if (cpu == -1)
> + cpu = hisi_ptt->trace_ctrl.default_cpu;
> +
> + /*
> + * Handle the interrupt on the same cpu which starts the trace to avoid
> + * context mismatch. Otherwise we'll trigger the WARN from the perf
> + * core in event_function_local().
> + */
> + WARN_ON(irq_set_affinity(pci_irq_vector(hisi_ptt->pdev, HISI_PTT_TRACE_DMA_IRQ),
> + cpumask_of(cpu)));
> +
> + ret = hisi_ptt_alloc_trace_buf(hisi_ptt);
> + if (ret) {
> + pci_dbg(hisi_ptt->pdev, "alloc trace buf failed, ret = %d\n", ret);
> + goto stop;
> + }
> +
> + buf = perf_aux_output_begin(handle, event);
> + if (!buf) {
> + pci_dbg(hisi_ptt->pdev, "aux output begin failed\n");
> + goto stop;
> + }
> +
> + buf->pos = handle->head % buf->length;
> +
> + ret = hisi_ptt_trace_start(hisi_ptt);
> + if (ret) {
> + pci_dbg(hisi_ptt->pdev, "trace start failed, ret = %d\n", ret);
> + perf_aux_output_end(handle, 0);
> + goto stop;
> + }
> +
> + mutex_unlock(&hisi_ptt->mutex);
> + return;
> +stop:
> + event->hw.state |= PERF_HES_STOPPED;
> + mutex_unlock(&hisi_ptt->mutex);
> +}
> +
> +static void hisi_ptt_pmu_stop(struct perf_event *event, int flags)
> +{
> + struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
> + struct hw_perf_event *hwc = &event->hw;
> +
> + if (hwc->state & PERF_HES_STOPPED)
> + return;
> +
> + mutex_lock(&hisi_ptt->mutex);
> + if (hisi_ptt->trace_ctrl.started) {
> + hisi_ptt_trace_end(hisi_ptt);
> + WARN(!hisi_ptt_wait_trace_hw_idle(hisi_ptt), "Device is still busy");
> + hisi_ptt_update_aux(hisi_ptt, hisi_ptt->trace_ctrl.buf_index, true);
> + }
> + mutex_unlock(&hisi_ptt->mutex);
> +
> + hwc->state |= PERF_HES_STOPPED;
> + perf_event_update_userpage(event);
> + hwc->state |= PERF_HES_UPTODATE;
> +}
> +
> +static int hisi_ptt_pmu_add(struct perf_event *event, int flags)
> +{
> + struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
> + struct hw_perf_event *hwc = &event->hw;
> + int cpu = event->cpu;
> +
> + /*
> + * Only allow the default cpu to add the event if user doesn't specify
> + * the cpus.
> + */
> + if (cpu == -1 && smp_processor_id() != hisi_ptt->trace_ctrl.default_cpu)
> + return 0;
> +
> + hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE;
> +
> + if (flags & PERF_EF_START) {
> + hisi_ptt_pmu_start(event, PERF_EF_RELOAD);
> + if (hwc->state & PERF_HES_STOPPED)
> + return -EINVAL;
> + }
> +
> + return 0;
> +}
> +
> +static void hisi_ptt_pmu_del(struct perf_event *event, int flags)
> +{
> + hisi_ptt_pmu_stop(event, PERF_EF_UPDATE);
> +}
> +
> +static int hisi_ptt_register_pmu(struct hisi_ptt *hisi_ptt)
> +{
> + u16 core_id, sicl_id;
> + char *pmu_name;
> + u32 reg;
> +
> + hisi_ptt->hisi_ptt_pmu = (struct pmu) {
> + .module = THIS_MODULE,
> + .capabilities = PERF_PMU_CAP_EXCLUSIVE | PERF_PMU_CAP_ITRACE,
> + .task_ctx_nr = perf_sw_context,
> + .attr_groups = hisi_ptt_pmu_groups,
> + .event_init = hisi_ptt_pmu_event_init,
> + .setup_aux = hisi_ptt_pmu_setup_aux,
> + .free_aux = hisi_ptt_pmu_free_aux,
> + .start = hisi_ptt_pmu_start,
> + .stop = hisi_ptt_pmu_stop,
> + .add = hisi_ptt_pmu_add,
> + .del = hisi_ptt_pmu_del,
> + };
> +
> + reg = readl(hisi_ptt->iobase + HISI_PTT_LOCATION);
> + core_id = FIELD_GET(HISI_PTT_CORE_ID, reg);
> + sicl_id = FIELD_GET(HISI_PTT_SICL_ID, reg);
> +
> + pmu_name = devm_kasprintf(&hisi_ptt->pdev->dev, GFP_KERNEL, "hisi_ptt%u_%u",
> + sicl_id, core_id);
> + if (!pmu_name)
> + return -ENOMEM;
> +
> + return perf_pmu_register(&hisi_ptt->hisi_ptt_pmu, pmu_name, -1);
> +}
> +
> +/*
> + * The DMA of PTT trace can only use direct mapping, due to some
> + * hardware restriction. Check whether there is an IOMMU or the
> + * policy of the IOMMU domain is passthrough, otherwise the trace
> + * cannot work.
> + *
> + * The PTT device is supposed to behind the ARM SMMUv3, which
/s/ the ARM SMMUv3/an ARM SMMUv3/
> + * should have passthrough the device by a quirk.
> + */
> +static int hisi_ptt_check_iommu_mapping(struct pci_dev *pdev)
> +{
> + struct iommu_domain *iommu_domain;
> +
> + iommu_domain = iommu_get_domain_for_dev(&pdev->dev);
> + if (!iommu_domain || iommu_domain->type == IOMMU_DOMAIN_IDENTITY)
> + return 0;
> +
> + return -EOPNOTSUPP;
> +}
> +
> +static int hisi_ptt_probe(struct pci_dev *pdev,
> + const struct pci_device_id *id)
> +{
> + struct hisi_ptt *hisi_ptt;
> + int ret;
> +
> + ret = hisi_ptt_check_iommu_mapping(pdev);
> + if (ret) {
> + pci_err(pdev, "requires direct DMA mappings\n");
> + return ret;
> + }
> +
> + hisi_ptt = devm_kzalloc(&pdev->dev, sizeof(*hisi_ptt), GFP_KERNEL);
> + if (!hisi_ptt)
> + return -ENOMEM;
> +
> + mutex_init(&hisi_ptt->mutex);
> + hisi_ptt->pdev = pdev;
> + pci_set_drvdata(pdev, hisi_ptt);
> +
> + ret = pcim_enable_device(pdev);
> + if (ret) {
> + pci_err(pdev, "failed to enable device, ret = %d\n", ret);
> + return ret;
> + }
> +
> + ret = pcim_iomap_regions(pdev, BIT(2), DRV_NAME);
> + if (ret) {
> + pci_err(pdev, "failed to remap io memory, ret = %d\n", ret);
> + return ret;
> + }
> +
> + hisi_ptt->iobase = pcim_iomap_table(pdev)[2];
> +
> + ret = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(64));
> + if (ret) {
> + pci_err(pdev, "failed to set 64 bit dma mask, ret = %d\n", ret);
> + return ret;
> + }
> +
> + pci_set_master(pdev);
> +
> + ret = hisi_ptt_register_irq(hisi_ptt);
> + if (ret)
> + return ret;
> +
> + ret = hisi_ptt_init_ctrls(hisi_ptt);
> + if (ret) {
> + pci_err(pdev, "failed to init controls, ret = %d\n", ret);
> + return ret;
> + }
> +
> + ret = hisi_ptt_register_pmu(hisi_ptt);
> + if (ret) {
> + pci_err(pdev, "failed to register PMU device, ret = %d", ret);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static void hisi_ptt_remove(struct pci_dev *pdev)
> +{
> + struct hisi_ptt *hisi_ptt = pci_get_drvdata(pdev);
> +
> + /*
> + * We have to manually unregister the PMU device rather than make it
> + * devres managed to keep order that the PMU device's unregistration
> + * is prior to the release of DMA buffers. As the DMA buffers are
> + * devm allocated when necessary which is after the registration of
> + * the PMU device.
> + */
do you really need to mention all this?
> + perf_pmu_unregister(&hisi_ptt->hisi_ptt_pmu);
> +}
> +
> +static const struct pci_device_id hisi_ptt_id_tbl[] = {
> + { PCI_DEVICE(PCI_VENDOR_ID_HUAWEI, 0xa12e) },
> + { }
> +};
> +MODULE_DEVICE_TABLE(pci, hisi_ptt_id_tbl);
> +
> +static struct pci_driver hisi_ptt_driver = {
> + .name = DRV_NAME,
> + .id_table = hisi_ptt_id_tbl,
> + .probe = hisi_ptt_probe,
> + .remove = hisi_ptt_remove,
> +};
> +module_pci_driver(hisi_ptt_driver);
> +
> +MODULE_LICENSE("GPL");
> +MODULE_AUTHOR("Yicong Yang <[email protected]>");
> +MODULE_DESCRIPTION("Driver for HiSilicon PCIe tune and trace device");
> diff --git a/drivers/hwtracing/ptt/hisi_ptt.h b/drivers/hwtracing/ptt/hisi_ptt.h
> new file mode 100644
> index 000000000000..29b6d6293d6c
> --- /dev/null
> +++ b/drivers/hwtracing/ptt/hisi_ptt.h
> @@ -0,0 +1,166 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Driver for HiSilicon PCIe tune and trace device
> + *
> + * Copyright (c) 2022 HiSilicon Technologies Co., Ltd.
> + * Author: Yicong Yang <[email protected]>
> + */
> +
> +#ifndef _HISI_PTT_H
> +#define _HISI_PTT_H
> +
> +#include <linux/bits.h>
> +#include <linux/list.h>
> +#include <linux/mutex.h>
> +#include <linux/pci.h>
> +#include <linux/perf_event.h>
> +#include <linux/types.h>
> +
> +#define DRV_NAME "hisi_ptt"
> +
> +/*
> + * The definition of the device registers and register fields.
> + */
> +#define HISI_PTT_TRACE_ADDR_SIZE 0x0800
> +#define HISI_PTT_TRACE_ADDR_BASE_LO_0 0x0810
> +#define HISI_PTT_TRACE_ADDR_BASE_HI_0 0x0814
> +#define HISI_PTT_TRACE_ADDR_STRIDE 0x8
> +#define HISI_PTT_TRACE_CTRL 0x0850
> +#define HISI_PTT_TRACE_CTRL_EN BIT(0)
> +#define HISI_PTT_TRACE_CTRL_RST BIT(1)
> +#define HISI_PTT_TRACE_CTRL_RXTX_SEL GENMASK(3, 2)
> +#define HISI_PTT_TRACE_CTRL_TYPE_SEL GENMASK(7, 4)
> +#define HISI_PTT_TRACE_CTRL_DATA_FORMAT BIT(14)
> +#define HISI_PTT_TRACE_CTRL_FILTER_MODE BIT(15)
> +#define HISI_PTT_TRACE_CTRL_TARGET_SEL GENMASK(31, 16)
> +#define HISI_PTT_TRACE_INT_STAT 0x0890
> +#define HISI_PTT_TRACE_INT_STAT_MASK GENMASK(3, 0)
> +#define HISI_PTT_TRACE_INT_MASK 0x0894
> +#define HISI_PTT_TRACE_WR_STS 0x08a0
> +#define HISI_PTT_TRACE_WR_STS_WRITE GENMASK(27, 0)
> +#define HISI_PTT_TRACE_WR_STS_BUFFER GENMASK(29, 28)
> +#define HISI_PTT_TRACE_STS 0x08b0
> +#define HISI_PTT_TRACE_IDLE BIT(0)
> +#define HISI_PTT_DEVICE_RANGE 0x0fe0
> +#define HISI_PTT_DEVICE_RANGE_UPPER GENMASK(31, 16)
> +#define HISI_PTT_DEVICE_RANGE_LOWER GENMASK(15, 0)
> +#define HISI_PTT_LOCATION 0x0fe8
> +#define HISI_PTT_CORE_ID GENMASK(15, 0)
> +#define HISI_PTT_SICL_ID GENMASK(31, 16)
> +
> +/* Parameters of PTT trace DMA part. */
> +#define HISI_PTT_TRACE_DMA_IRQ 0
> +#define HISI_PTT_TRACE_BUF_CNT 4
> +#define HISI_PTT_TRACE_BUF_SIZE SZ_4M
> +#define HISI_PTT_TRACE_TOTAL_BUF_SIZE (HISI_PTT_TRACE_BUF_SIZE * \
> + HISI_PTT_TRACE_BUF_CNT)
> +/* Wait time for hardware DMA to reset */
> +#define HISI_PTT_RESET_TIMEOUT_US 10UL
> +#define HISI_PTT_RESET_POLL_INTERVAL_US 1UL
> +/* Poll timeout and interval for waiting hardware work to finish */
> +#define HISI_PTT_WAIT_TRACE_TIMEOUT_US 100UL
> +#define HISI_PTT_WAIT_POLL_INTERVAL_US 10UL
> +
> +#define HISI_PCIE_CORE_PORT_ID(devfn) (PCI_FUNC(devfn) << 1)
> +
> +/**
> + * struct hisi_ptt_dma_buffer - describe a single trace buffer of PTT trace.
> + * The detail of the data format is described
> + * in the documentation of PTT device.
> + * @dma: DMA address of this buffer visible to the device
> + * @addr: virtual address of this buffer visible to the cpu
> + */
> +struct hisi_ptt_dma_buffer {
> + dma_addr_t dma;
> + void *addr;
> +};
> +
> +/**
> + * struct hisi_ptt_trace_ctrl - control and status of PTT trace
> + * @trace_buf: array of the trace buffers for holding the trace data.
> + * the length will be HISI_PTT_TRACE_BUF_CNT.
> + * @handle: perf output handle of current trace session
> + * @default_cpu: default cpu to start the trace session
> + * @buf_index: the index of current using trace buffer
> + * @started: current trace status, true for started
> + * @is_port: whether we're tracing root port or not
> + * @direction: direction of the TLP headers to trace
> + * @filter: filter value for tracing the TLP headers
> + * @format: format of the TLP headers to trace
> + * @type: type of the TLP headers to trace
> + */
> +struct hisi_ptt_trace_ctrl {
> + struct hisi_ptt_dma_buffer *trace_buf;
> + struct perf_output_handle handle;
> + int default_cpu;
> + u32 buf_index;
> + bool started;
> + bool is_port;
> + u32 direction:2;
> + u32 filter:16;
> + u32 format:1;
> + u32 type:4;
> +};
> +
> +/**
> + * struct hisi_ptt_filter_desc - descriptor of the PTT trace filter
> + * @list: entry of this descriptor in the filter list
> + * @pdev: pci_dev related to this filter
> + */
> +struct hisi_ptt_filter_desc {
> + struct list_head list;
> + struct pci_dev *pdev;
> +};
> +
> +
> +/**
> + * struct hisi_ptt_pmu_buf - descriptor of the AUX buffer of PTT trace
> + * @length: size of the AUX buffer
> + * @nr_pages: number of pages of the AUX buffer
> + * @base: start address of AUX buffer
> + * @pos: position in the AUX buffer to commit traced data
> + */
> +struct hisi_ptt_pmu_buf {
> + size_t length;
> + int nr_pages;
> + void *base;
> + long pos;
> +};
> +
> +/**
> + * struct hisi_ptt - per PTT device data
> + * @trace_ctrl: the control information of PTT trace
> + * @hisi_ptt_pmu: the pum device of trace
> + * @iobase: base IO address of the device
> + * @pdev: pci_dev of this PTT device
> + * @mutex: mutex to protect the filter list and serialize the perf process.
> + * @upper: the upper BDF range of the PCI devices managed by this PTT device
> + * @lower: the lower BDF range of the PCI devices managed by this PTT device
> + * @port_filters: the filter list of root ports
> + * @req_filters: the filter list of requester ID
> + * @port_mask: port mask of the managed root ports
> + */
> +struct hisi_ptt {
> + struct hisi_ptt_trace_ctrl trace_ctrl;
> + struct pmu hisi_ptt_pmu;
> + void __iomem *iobase;
> + struct pci_dev *pdev;
> + struct mutex mutex;
> + u32 upper;
upper_bdf would be a better name
people don't want to always refer to comments to check the meaning
> + u32 lower;
> +
> + /*
> + * The trace TLP headers can either be filtered by certain
> + * root port, or by the requester ID. Organize the filters
> + * by @port_filters and @req_filters here. The mask of all
> + * the valid ports is also cached for doing sanity check
> + * of user input.
> + */
> + struct list_head port_filters;
> + struct list_head req_filters;
> + u16 port_mask;
> +};
> +
> +#define to_hisi_ptt(pmu) container_of(pmu, struct hisi_ptt, hisi_ptt_pmu)
> +
> +#endif /* _HISI_PTT_H */
>>> +static int hisi_ptt_alloc_trace_buf(struct hisi_ptt *hisi_ptt)
>>> +{
>>> +Â Â Â struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
>>> +Â Â Â struct device *dev = &hisi_ptt->pdev->dev;
>>> +Â Â Â int i;
>>> +
>>> +Â Â Â hisi_ptt->trace_ctrl.buf_index = 0;
>>> +
>>> +Â Â Â /* If the trace buffer has already been allocated, zero it. */
>>
>> I am not sure why this is not called from the probe
>>
>
> The buffer allocation is done when necessary as driver will probe the device on booting but
> the user may never use it. In this condition it's a waste of memory if we allocate the buffers
> in probe. Currently we'll allocate 16M memory for 4 buffers.
>
But that's just not how we do things. We setup the driver fully to be
used in the probe. If the user cannot really afford the memory then
he/she should not load the driver.
In addition, this driver would be used in a machine which will have
gigbytes of memory, so I think that the memory mentioned here is
relatively insignificant.
> So this function is called every time before we start trace. In the first time it will allocate
> the DMA buffers and it the other times it just zero the buffers to clear the data of last time.
>
>>> +Â Â Â if (ctrl->trace_buf) {
>>> +Â Â Â Â Â Â Â for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; i++)
>>> +Â Â Â Â Â Â Â Â Â Â Â memset(ctrl->trace_buf[i].addr, 0, HISI_PTT_TRACE_BUF_SIZE);
>>> +Â Â Â Â Â Â Â return 0;
>>> +Â Â Â }
>>> +
>>> +Â Â Â ctrl->trace_buf = devm_kcalloc(dev, HISI_PTT_TRACE_BUF_CNT,
>>> +Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â sizeof(struct hisi_ptt_dma_buffer), GFP_KERNEL);
>>
>> sizeof(*ctrl->trace_buf) may be better
>>
>
> ok.
>
>>> +Â Â Â if (!ctrl->trace_buf)
>>> +Â Â Â Â Â Â Â return -ENOMEM;
>>> +
>>> +Â Â Â for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; ++i) {
>>> +Â Â Â Â Â Â Â ctrl->trace_buf[i].addr = dmam_alloc_coherent(dev, HISI_PTT_TRACE_BUF_SIZE,
>>> +Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â &ctrl->trace_buf[i].dma,
>>> +Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â GFP_KERNEL);
>>> +Â Â Â Â Â Â Â if (!ctrl->trace_buf[i].addr) {
>>> +Â Â Â Â Â Â Â Â Â Â Â hisi_ptt_free_trace_buf(hisi_ptt);
>>> +Â Â Â Â Â Â Â Â Â Â Â return -ENOMEM;
>>> +Â Â Â Â Â Â Â }
>>> +Â Â Â }
>>> +
>>> +Â Â Â return 0;
>>> +}
>>> +
>>> +static void hisi_ptt_trace_end(struct hisi_ptt *hisi_ptt)
>>> +{
>>> +Â Â Â writel(0, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
>>> +Â Â Â hisi_ptt->trace_ctrl.started = false;
>>> +}
>>> +
>>> +static int hisi_ptt_trace_start(struct hisi_ptt *hisi_ptt)
>>> +{
>>> +Â Â Â struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
>>> +Â Â Â u32 val;
>>> +Â Â Â int i;
>>> +
>>> +Â Â Â /* Check device idle before start trace */
>>> +Â Â Â if (!hisi_ptt_wait_trace_hw_idle(hisi_ptt)) {
>>> +Â Â Â Â Â Â Â pci_err(hisi_ptt->pdev, "Failed to start trace, the device is still busy\n");
>>> +Â Â Â Â Â Â Â return -EBUSY;
>>> +Â Â Â }
>>> +
>>> +Â Â Â ctrl->started = true;
>>> +
>>> +Â Â Â /* Reset the DMA before start tracing */
>>> +Â Â Â val = readl(hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
>>> +Â Â Â val |= HISI_PTT_TRACE_CTRL_RST;
>>> +Â Â Â writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
>>> +
>>> +Â Â Â hisi_ptt_wait_dma_reset_done(hisi_ptt);
>>> +
>>> +Â Â Â val = readl(hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
>>> +Â Â Â val &= ~HISI_PTT_TRACE_CTRL_RST;
>>> +Â Â Â writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
>>> +
>>> +Â Â Â /* Clear the interrupt status */
>>> +Â Â Â writel(HISI_PTT_TRACE_INT_STAT_MASK, hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
>>> +Â Â Â writel(0, hisi_ptt->iobase + HISI_PTT_TRACE_INT_MASK);
>>> +
>>> +Â Â Â /* Configure the trace DMA buffer */
>>
>> I am not sure why this sort of thing is done outside probing
>>
...
>>> +
>>> +Â Â Â val = FIELD_GET(HISI_PTT_PMU_DIRECTION_MASK, event->attr.config);
>>> +Â Â Â ret = hisi_ptt_trace_valid_config_onehot(val, hisi_ptt_trace_available_direction,
>>
>> how about put all those arrays in hisi_ptt_trace_valid_config_onehot() and pass some flag to say which array you want to use? Or something like that. Passing the arrays in this fashion is messy
>>
>
> Since there are 3 configs (type, direction, format) with different available range and setting method (onehot, non-onehot),
> moving the arrays into the valid checking function means we need to recognize the config types (passed by the caller but need
> to know the available value array) and the checking method together. That may make the code more complex than now: 1st picking
> up the right array and judge wich checking method this array applied and 2nd do the checking.
>
> Currently it's designed to decouple the checking method and the available value array. The hisi_ptt_trace_valid_config{_onehot}()
> won't care about which array to use since caller take responsibilty for this. So perhaps current approach is simple and clear
> enough.
A couple of points:
- hisi_ptt_trace_valid_config_type() only has 1x caller so can make it
dedicated for that caller
- there is not much code in hisi_ptt_trace_valid_config_onshot(), so ok
to duplicate if makes overall code look better
So I think dedicated functions make the code simpler, easier to follow,
and maintain:
static int hisi_ptt_trace_valid_config_dir(u32 val)
{
int i;
/*
* The supported value of the direction parameter. See hisi_ptt.rst
* documentation for more details.
*/
static const u32 hisi_ptt_trace_available_direction[] = {
0,
1,
2,
3,
};
for (i = 0; i < ARRAY_SIZE(hisi_ptt_trace_available_direction); i++)
if (val == hisi_ptt_trace_available_direction[i])
return 0;
return -EINVAL;
}
static int hisi_ptt_trace_valid_config_format(u32 val)
{
int i;
static const u32 hisi_ptt_trace_availble_format[] = {
0, /* 4DW */
1, /* 8DW */
};
for (i = 0; i < ARRAY_SIZE(hisi_ptt_trace_availble_format); i++)
if (val == hisi_ptt_trace_availble_format[i])
return 0;
return -EINVAL;
}
static int hisi_ptt_trace_valid_config_type(u32 val)
{
int i;
/* Different types can be set simultaneously */
static const u32 hisi_ptt_trace_available_type[] = {
1, /* posted_request */
2, /* non-posted_request */
4, /* completion */
};
for (i = 0; i < ARRAY_SIZE(hisi_ptt_trace_available_type); i++)
val &= ~hisi_ptt_trace_available_type[i];
if (val)
return -EINVAL;
return 0;
}
...
static int hisi_ptt_pmu_event_init(struct perf_event *event)
{
...
val = FIELD_GET(HISI_PTT_PMU_DIRECTION_MASK, event->attr.config);
ret = hisi_ptt_trace_valid_config_dir(val);
if (ret < 0)
goto out;
ctrl->direction = val;
val = FIELD_GET(HISI_PTT_PMU_TYPE_MASK, event->attr.config);
ret = hisi_ptt_trace_valid_config_type(val);
if (ret < 0)
goto out;
ctrl->type = val;
val = FIELD_GET(HISI_PTT_PMU_FORMAT_MASK, event->attr.config);
ret = hisi_ptt_trace_valid_config_format(val);
if (ret < 0)
goto out;
ctrl->format = val;
...
}
>
>>
>>> +Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â ARRAY_SIZE(hisi_ptt_trace_available_direction));
>>> +Â Â Â if (ret < 0)
>>> +Â Â Â Â Â Â Â goto out;
>>> +Â Â Â ctrl->direction = val;
>>> +
>>> +Â Â Â val = FIELD_GET(HISI_PTT_PMU_TYPE_MASK, event->attr.config);
>>> +Â Â Â ret = hisi_ptt_trace_valid_config(val, hisi_ptt_trace_available_type,
>>> +Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â ARRAY_SIZE(hisi_ptt_trace_available_type));
>>> +Â Â Â if (ret < 0)
>>> +Â Â Â Â Â Â Â goto out;
>>> +Â Â Â ctrl->type = val;
>>> +
>>> +Â Â Â val = FIELD_GET(HISI_PTT_PMU_FORMAT_MASK, event->attr.config);
>>> +Â Â Â ret = hisi_ptt_trace_valid_config_onehot(val, hisi_ptt_trace_availble_format,
>>> +Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â ARRAY_SIZE(hisi_ptt_trace_availble_format));
>>> +Â Â Â if (ret < 0)
>>> +Â Â Â Â Â Â Â goto out;
>>> +Â Â Â ctrl->format = val;
>>> +
>>> +out:
>>> +Â Â Â mutex_unlock(&hisi_ptt->mutex);
>>> +Â Â Â return ret;
>>> +}
>>> +
>>> +static void *hisi_ptt_pmu_setup_aux(struct perf_event *event, void **pages,
>>> +Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â int nr_pages, bool overwrite)
>>> +{
>>> +Â Â Â struct hisi_ptt_pmu_buf *buf;
>>> +Â Â Â struct page **pagelist;
>>> +Â Â Â int i;
>>> +
>>> +Â Â Â if (overwrite) {
>>> +Â Â Â Â Â Â Â dev_warn(event->pmu->dev, "Overwrite mode is not supported\n");
>>> +Â Â Â Â Â Â Â return NULL;
>>> +Â Â Â }
>>> +
>>> +Â Â Â /* If the pages size less than buffers, we cannot start trace */
>>> +Â Â Â if (nr_pages < HISI_PTT_TRACE_TOTAL_BUF_SIZE / PAGE_SIZE)
>>> +Â Â Â Â Â Â Â return NULL;
>>> +
>>> +Â Â Â buf = kzalloc(sizeof(*buf), GFP_KERNEL);
>>> +Â Â Â if (!buf)
>>> +Â Â Â Â Â Â Â return NULL;
>>> +
>>> +Â Â Â pagelist = kcalloc(nr_pages, sizeof(*pagelist), GFP_KERNEL);
>>> +Â Â Â if (!pagelist) {
>>> +Â Â Â Â Â Â Â kfree(buf);
>>> +Â Â Â Â Â Â Â return NULL;
>>> +Â Â Â }
>>> +
>>> +Â Â Â for (i = 0; i < nr_pages; i++)
>>> +Â Â Â Â Â Â Â pagelist[i] = virt_to_page(pages[i]);
>>> +
>>> +Â Â Â buf->base = vmap(pagelist, nr_pages, VM_MAP, PAGE_KERNEL);
>>> +Â Â Â if (!buf->base) {
>>> +Â Â Â Â Â Â Â kfree(pagelist);
>>> +Â Â Â Â Â Â Â kfree(buf);
>>> +Â Â Â Â Â Â Â return NULL;
>>> +Â Â Â }
>>> +
>>> +Â Â Â buf->nr_pages = nr_pages;
>>> +Â Â Â buf->length = nr_pages * PAGE_SIZE;
>>> +Â Â Â buf->pos = 0;
>>> +
>>> +Â Â Â kfree(pagelist);
>>> +Â Â Â return buf;
>>> +}
>>> +
>>> +static void hisi_ptt_pmu_free_aux(void *aux)
>>> +{
>>> +Â Â Â struct hisi_ptt_pmu_buf *buf = aux;
>>> +
>>> +Â Â Â vunmap(buf->base);
>>> +Â Â Â kfree(buf);
>>> +}
>>> +
>>> +static void hisi_ptt_pmu_start(struct perf_event *event, int flags)
>>> +{
>>> +Â Â Â struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
>>> +Â Â Â struct perf_output_handle *handle = &hisi_ptt->trace_ctrl.handle;
>>> +Â Â Â struct hw_perf_event *hwc = &event->hw;
>>> +Â Â Â struct hisi_ptt_pmu_buf *buf;
>>> +Â Â Â int cpu = event->cpu;
>>> +Â Â Â int ret;
>>> +
>>> +Â Â Â hwc->state = 0;
>>> +Â Â Â mutex_lock(&hisi_ptt->mutex);
>>> +Â Â Â if (hisi_ptt->trace_ctrl.started) {
>>> +Â Â Â Â Â Â Â pci_dbg(hisi_ptt->pdev, "trace has already started\n");
>>
>> doesn't perf core guard against this sort of thing?
>>
>
> Maybe not as tested. The perf core will start the events 1)on the cpus user specified or
> 2)on all the cpus, but the PTT trace is intended to start once on one cpu.
>
> For the 2) case, the driver will make default cpu to start the trace and block others
> in pmu::add(). For the 1) case we'll met the condition here. So the started status is
> test here to avoid a second start.
if this is a realistic and sensible usecase then it would be nice to
handle in core perf code at some stage
>
>>> +Â Â Â Â Â Â Â goto stop;
>>> +Â Â Â }
>>> +
>>> +Â Â Â if (cpu == -1)
>>> +Â Â Â Â Â Â Â cpu = hisi_ptt->trace_ctrl.default_cpu;
>>> +
>>> +Â Â Â /*
>>> +Â Â Â Â * Handle the interrupt on the same cpu which starts the trace to avoid
>>> +Â Â Â Â * context mismatch. Otherwise we'll trigger the WARN from the perf
>>> +Â Â Â Â * core in event_function_local().
>>> +Â Â Â Â */
>>> +Â Â Â WARN_ON(irq_set_affinity(pci_irq_vector(hisi_ptt->pdev, HISI_PTT_TRACE_DMA_IRQ),
>>> +Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â cpumask_of(cpu)));
>>> +
>>> +Â Â Â ret = hisi_ptt_alloc_trace_buf(hisi_ptt);
>>> +Â Â Â if (ret) {
>>> +Â Â Â Â Â Â Â pci_dbg(hisi_ptt->pdev, "alloc trace buf failed, ret = %d\n", ret);
>>> +Â Â Â Â Â Â Â goto stop;
>>> +Â Â Â }
>>> +
>>> +Â Â Â buf = perf_aux_output_begin(handle, event);
>>> +Â Â Â if (!buf) {
>>> +Â Â Â Â Â Â Â pci_dbg(hisi_ptt->pdev, "aux output begin failed\n");
>>> +Â Â Â Â Â Â Â goto stop;
>>> +Â Â Â }
>>> +
>>> +Â Â Â buf->pos = handle->head % buf->length;
>>> +
>>> +Â Â Â ret = hisi_ptt_trace_start(hisi_ptt);
>>> +Â Â Â if (ret) {
>>> +Â Â Â Â Â Â Â pci_dbg(hisi_ptt->pdev, "trace start failed, ret = %d\n", ret);
>>> +Â Â Â Â Â Â Â perf_aux_output_end(handle, 0);
>>> +Â Â Â Â Â Â Â goto stop;
>>> +Â Â Â }
>>> +
>>> +Â Â Â mutex_unlock(&hisi_ptt->mutex);
>>> +Â Â Â return;
>>> +stop:
>>> +Â Â Â event->hw.state |= PERF_HES_STOPPED;
>>> +Â Â Â mutex_unlock(&hisi_ptt->mutex);
>>> +}
>>> +
>>> +static void hisi_ptt_pmu_stop(struct perf_event *event, int flags)
>>> +{
>>> +Â Â Â struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
>>> +Â Â Â struct hw_perf_event *hwc = &event->hw;
>>> +
>>> +Â Â Â if (hwc->state & PERF_HES_STOPPED)
>>> +Â Â Â Â Â Â Â return;
>>> +
>>> +Â Â Â mutex_lock(&hisi_ptt->mutex);
>>> +Â Â Â if (hisi_ptt->trace_ctrl.started) {
>>> +Â Â Â Â Â Â Â hisi_ptt_trace_end(hisi_ptt);
>>> +Â Â Â Â Â Â Â WARN(!hisi_ptt_wait_trace_hw_idle(hisi_ptt), "Device is still busy");
>>> +Â Â Â Â Â Â Â hisi_ptt_update_aux(hisi_ptt, hisi_ptt->trace_ctrl.buf_index, true);
>>> +Â Â Â }
>>> +Â Â Â mutex_unlock(&hisi_ptt->mutex);
>>> +
>>> +Â Â Â hwc->state |= PERF_HES_STOPPED;
>>> +Â Â Â perf_event_update_userpage(event);
>>> +Â Â Â hwc->state |= PERF_HES_UPTODATE;
>>> +}
>>> +
>>> +static int hisi_ptt_pmu_add(struct perf_event *event, int flags)
>>> +{
>>> +Â Â Â struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
>>> +Â Â Â struct hw_perf_event *hwc = &event->hw;
>>> +Â Â Â int cpu = event->cpu;
>>> +
>>> +Â Â Â /*
>>> +Â Â Â Â * Only allow the default cpu to add the event if user doesn't specify
>>> +Â Â Â Â * the cpus.
>>> +Â Â Â Â */
>>> +Â Â Â if (cpu == -1 && smp_processor_id() != hisi_ptt->trace_ctrl.default_cpu)
>>> +Â Â Â Â Â Â Â return 0;
>>> +
>>> +Â Â Â hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE;
>>> +
>>> +Â Â Â if (flags & PERF_EF_START) {
>>> +Â Â Â Â Â Â Â hisi_ptt_pmu_start(event, PERF_EF_RELOAD);
>>> +Â Â Â Â Â Â Â if (hwc->state & PERF_HES_STOPPED)
>>> +Â Â Â Â Â Â Â Â Â Â Â return -EINVAL;
>>> +Â Â Â }
>>> +
>>> +Â Â Â return 0;
>>> +}
>>> +
>>> +static void hisi_ptt_pmu_del(struct perf_event *event, int flags)
>>> +{
>>> +Â Â Â hisi_ptt_pmu_stop(event, PERF_EF_UPDATE);
>>> +}
>>> +
>>> +static int hisi_ptt_register_pmu(struct hisi_ptt *hisi_ptt)
>>> +{
>>> +Â Â Â u16 core_id, sicl_id;
>>> +Â Â Â char *pmu_name;
>>> +Â Â Â u32 reg;
>>> +
>>> +Â Â Â hisi_ptt->hisi_ptt_pmu = (struct pmu) {
>>> +       .module       = THIS_MODULE,
>>> +       .capabilities   = PERF_PMU_CAP_EXCLUSIVE | PERF_PMU_CAP_ITRACE,
>>> +       .task_ctx_nr   = perf_sw_context,
>>> +       .attr_groups   = hisi_ptt_pmu_groups,
>>> +       .event_init   = hisi_ptt_pmu_event_init,
>>> +       .setup_aux   = hisi_ptt_pmu_setup_aux,
>>> +       .free_aux   = hisi_ptt_pmu_free_aux,
>>> +       .start       = hisi_ptt_pmu_start,
>>> +       .stop       = hisi_ptt_pmu_stop,
>>> +       .add       = hisi_ptt_pmu_add,
>>> +       .del       = hisi_ptt_pmu_del,
>>> +Â Â Â };
>>> +
>>> +Â Â Â reg = readl(hisi_ptt->iobase + HISI_PTT_LOCATION);
>>> +Â Â Â core_id = FIELD_GET(HISI_PTT_CORE_ID, reg);
>>> +Â Â Â sicl_id = FIELD_GET(HISI_PTT_SICL_ID, reg);
>>> +
>>> +Â Â Â pmu_name = devm_kasprintf(&hisi_ptt->pdev->dev, GFP_KERNEL, "hisi_ptt%u_%u",
>>> +Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â sicl_id, core_id);
>>> +Â Â Â if (!pmu_name)
>>> +Â Â Â Â Â Â Â return -ENOMEM;
>>> +
>>> +Â Â Â return perf_pmu_register(&hisi_ptt->hisi_ptt_pmu, pmu_name, -1);
>>> +}
>>> +
>>> +/*
>>> + * The DMA of PTT trace can only use direct mapping, due to some
>>> + * hardware restriction. Check whether there is an IOMMU or the
>>> + * policy of the IOMMU domain is passthrough, otherwise the trace
>>> + * cannot work.
>>> + *
>>> + * The PTT device is supposed to behind the ARM SMMUv3, which
>>
>> /s/ the ARM SMMUv3/an ARM SMMUv3/
>>
> ok.
>>> + * should have passthrough the device by a quirk.
>>> + */
>>> +static int hisi_ptt_check_iommu_mapping(struct pci_dev *pdev)
>>> +{
>>> +Â Â Â struct iommu_domain *iommu_domain;
>>> +
>>> +Â Â Â iommu_domain = iommu_get_domain_for_dev(&pdev->dev);
>>> +Â Â Â if (!iommu_domain || iommu_domain->type == IOMMU_DOMAIN_IDENTITY)
>>> +Â Â Â Â Â Â Â return 0;
>>> +
>>> +Â Â Â return -EOPNOTSUPP;
>>> +}
>>> +
>>> +static int hisi_ptt_probe(struct pci_dev *pdev,
>>> +Â Â Â Â Â Â Â Â Â Â Â Â Â const struct pci_device_id *id)
>>> +{
>>> +Â Â Â struct hisi_ptt *hisi_ptt;
>>> +Â Â Â int ret;
>>> +
>>> +Â Â Â ret = hisi_ptt_check_iommu_mapping(pdev);
>>> +Â Â Â if (ret) {
>>> +Â Â Â Â Â Â Â pci_err(pdev, "requires direct DMA mappings\n");
>>> +Â Â Â Â Â Â Â return ret;
>>> +Â Â Â }
>>> +
>>> +Â Â Â hisi_ptt = devm_kzalloc(&pdev->dev, sizeof(*hisi_ptt), GFP_KERNEL);
>>> +Â Â Â if (!hisi_ptt)
>>> +Â Â Â Â Â Â Â return -ENOMEM;
>>> +
>>> +Â Â Â mutex_init(&hisi_ptt->mutex);
>>> +Â Â Â hisi_ptt->pdev = pdev;
>>> +Â Â Â pci_set_drvdata(pdev, hisi_ptt);
>>> +
>>> +Â Â Â ret = pcim_enable_device(pdev);
>>> +Â Â Â if (ret) {
>>> +Â Â Â Â Â Â Â pci_err(pdev, "failed to enable device, ret = %d\n", ret);
>>> +Â Â Â Â Â Â Â return ret;
>>> +Â Â Â }
>>> +
>>> +Â Â Â ret = pcim_iomap_regions(pdev, BIT(2), DRV_NAME);
>>> +Â Â Â if (ret) {
>>> +Â Â Â Â Â Â Â pci_err(pdev, "failed to remap io memory, ret = %d\n", ret);
>>> +Â Â Â Â Â Â Â return ret;
>>> +Â Â Â }
>>> +
>>> +Â Â Â hisi_ptt->iobase = pcim_iomap_table(pdev)[2];
>>> +
>>> +Â Â Â ret = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(64));
>>> +Â Â Â if (ret) {
>>> +Â Â Â Â Â Â Â pci_err(pdev, "failed to set 64 bit dma mask, ret = %d\n", ret);
>>> +Â Â Â Â Â Â Â return ret;
>>> +Â Â Â }
>>> +
>>> +Â Â Â pci_set_master(pdev);
>>> +
>>> +Â Â Â ret = hisi_ptt_register_irq(hisi_ptt);
>>> +Â Â Â if (ret)
>>> +Â Â Â Â Â Â Â return ret;
>>> +
>>> +Â Â Â ret = hisi_ptt_init_ctrls(hisi_ptt);
>>> +Â Â Â if (ret) {
>>> +Â Â Â Â Â Â Â pci_err(pdev, "failed to init controls, ret = %d\n", ret);
>>> +Â Â Â Â Â Â Â return ret;
>>> +Â Â Â }
>>> +
>>> +Â Â Â ret = hisi_ptt_register_pmu(hisi_ptt);
>>> +Â Â Â if (ret) {
>>> +Â Â Â Â Â Â Â pci_err(pdev, "failed to register PMU device, ret = %d", ret);
>>> +Â Â Â Â Â Â Â return ret;
>>> +Â Â Â }
>>> +
>>> +Â Â Â return 0;
>>> +}
>>> +
>>> +static void hisi_ptt_remove(struct pci_dev *pdev)
>>> +{
>>> +Â Â Â struct hisi_ptt *hisi_ptt = pci_get_drvdata(pdev);
>>> +
>>> +Â Â Â /*
>>> +Â Â Â Â * We have to manually unregister the PMU device rather than make it
>>> +Â Â Â Â * devres managed to keep order that the PMU device's unregistration
>>> +Â Â Â Â * is prior to the release of DMA buffers. As the DMA buffers are
>>> +Â Â Â Â * devm allocated when necessary which is after the registration of
>>> +Â Â Â Â * the PMU device.
>>> +Â Â Â Â */
>>
>> do you really need to mention all this?
>>
>
> I think yes. Otherwise people may ask why not register PMU device in managed
> way as well.
I expect devres work to be done after hisi_ptt_remove() so I would know
this...
Hi Bjorn,
Since it's a device about tuning and analyzing PCIe link in your realm and you've given
helpful comments in RFC and v1 version, looking forward to see your opnion on this
driver as the user interface has changed to perf. Also to confirm that the hotplug problem
mentioned in RFC[1] has been resolved in a proper way.
[1] https://lore.kernel.org/linux-pci/20200710230913.GA90375@bjorn-Precision-5520/
Thanks.
On 2022/4/7 20:58, Yicong Yang wrote:
> HiSilicon PCIe tune and trace device (PTT) is a PCIe Root Complex
> integrated Endpoint (RCiEP) device, providing the capability
> to dynamically monitor and tune the PCIe traffic (tune),
> and trace the TLP headers (trace).
>
> PTT tune is designed for monitoring and adjusting PCIe link parameters.
> We provide several parameters of the PCIe link. Through the driver,
> user can adjust the value of certain parameter to affect the PCIe link
> for the purpose of enhancing the performance in certian situation.
>
> PTT trace is designed for dumping the TLP headers to the memory, which
> can be used to analyze the transactions and usage condition of the PCIe
> Link. Users can choose filters to trace headers, by either requester
> ID, or those downstream of a set of Root Ports on the same core of the
> PTT device. It's also supported to trace the headers of certain type and
> of certain direction.
>
> The driver registers a PMU device for each PTT device. The trace can
> be used through `perf record` and the traced headers can be decoded
> by `perf report`. The perf command support for the device is also
> added in this patchset. The tune can be used through the sysfs
> attributes of related PMU device. See the documentation for the
> detailed usage.
>
> Change since v6:
> - Fix W=1 errors reported by lkp test, thanks
>
> Change since v5:
> - Squash the PMU patch into PATCH 2 suggested by John
> - refine the commit message of PATCH 1 and some comments
> Link: https://lore.kernel.org/lkml/[email protected]/
>
> Change since v4:
> Address the comments from Jonathan, John and Ma Ca, thanks.
> - Use devm* also for allocating the DMA buffers
> - Remove the IRQ handler stub in Patch 2
> - Make functions waiting for hardware state return boolean
> - Manual remove the PMU device as it should be removed first
> - Modifier the orders in probe and removal to make them matched well
> - Make available {directions,type,format} array const and non-global
> - Using the right filter list in filters show and well protect the
> list with mutex
> - Record the trace status with a boolean @started rather than enum
> - Optimize the process of finding the PTT devices of the perf-tool
> Link: https://lore.kernel.org/linux-pci/[email protected]/
>
> Change since v3:
> Address the comments from Jonathan and John, thanks.
> - drop members in the common struct which can be get on the fly
> - reduce buffer struct and organize the buffers with array instead of list
> - reduce the DMA reset wait time to avoid long time busy loop
> - split the available_filters sysfs attribute into two files, for root port
> and requester respectively. Update the documentation accordingly
> - make IOMMU mapping check earlier in probe to avoid race condition. Also
> make IOMMU quirk patch prior to driver in the series
> - Cleanups and typos fixes from John and Jonathan
> Link: https://lore.kernel.org/linux-pci/[email protected]/
>
> Change since v2:
> - address the comments from Mathieu, thanks.
> - rename the directory to ptt to match the function of the device
> - spinoff the declarations to a separate header
> - split the trace function to several patches
> - some other comments.
> - make default smmu domain type of PTT device to identity
> Drop the RMR as it's not recommended and use an iommu_def_domain_type
> quirk to passthrough the device DMA as suggested by Robin.
> Link: https://lore.kernel.org/linux-pci/[email protected]/
>
> Change since v1:
> - switch the user interface of trace to perf from debugfs
> - switch the user interface of tune to sysfs from debugfs
> - add perf tool support to start trace and decode the trace data
> - address the comments of documentation from Bjorn
> - add RMR[1] support of the device as trace works in RMR mode or
> direct DMA mode. RMR support is achieved by common APIs rather
> than the APIs implemented in [1].
> Link: https://lore.kernel.org/lkml/[email protected]/
> [1] https://lore.kernel.org/linux-acpi/[email protected]/
>
> Qi Liu (1):
> perf tool: Add support for HiSilicon PCIe Tune and Trace device driver
>
> Yicong Yang (6):
> iommu/arm-smmu-v3: Make default domain type of HiSilicon PTT device to
> identity
> hwtracing: Add trace function support for HiSilicon PCIe Tune and
> Trace device
> hisi_ptt: Add support for dynamically updating the filter list
> hisi_ptt: Add tune function support for HiSilicon PCIe Tune and Trace
> device
> docs: Add HiSilicon PTT device driver documentation
> MAINTAINERS: Add maintainer for HiSilicon PTT driver
>
> Documentation/trace/hisi-ptt.rst | 303 +++++
> MAINTAINERS | 7 +
> drivers/Makefile | 1 +
> drivers/hwtracing/Kconfig | 2 +
> drivers/hwtracing/ptt/Kconfig | 12 +
> drivers/hwtracing/ptt/Makefile | 2 +
> drivers/hwtracing/ptt/hisi_ptt.c | 1161 +++++++++++++++++
> drivers/hwtracing/ptt/hisi_ptt.h | 220 ++++
> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 16 +
> tools/perf/arch/arm/util/auxtrace.c | 76 +-
> tools/perf/arch/arm/util/pmu.c | 3 +
> tools/perf/arch/arm64/util/Build | 2 +-
> tools/perf/arch/arm64/util/hisi_ptt.c | 195 +++
> tools/perf/util/Build | 2 +
> tools/perf/util/auxtrace.c | 4 +
> tools/perf/util/auxtrace.h | 1 +
> tools/perf/util/hisi-ptt-decoder/Build | 1 +
> .../hisi-ptt-decoder/hisi-ptt-pkt-decoder.c | 170 +++
> .../hisi-ptt-decoder/hisi-ptt-pkt-decoder.h | 28 +
> tools/perf/util/hisi_ptt.c | 218 ++++
> tools/perf/util/hisi_ptt.h | 28 +
> 21 files changed, 2448 insertions(+), 4 deletions(-)
> create mode 100644 Documentation/trace/hisi-ptt.rst
> create mode 100644 drivers/hwtracing/ptt/Kconfig
> create mode 100644 drivers/hwtracing/ptt/Makefile
> create mode 100644 drivers/hwtracing/ptt/hisi_ptt.c
> create mode 100644 drivers/hwtracing/ptt/hisi_ptt.h
> create mode 100644 tools/perf/arch/arm64/util/hisi_ptt.c
> create mode 100644 tools/perf/util/hisi-ptt-decoder/Build
> create mode 100644 tools/perf/util/hisi-ptt-decoder/hisi-ptt-pkt-decoder.c
> create mode 100644 tools/perf/util/hisi-ptt-decoder/hisi-ptt-pkt-decoder.h
> create mode 100644 tools/perf/util/hisi_ptt.c
> create mode 100644 tools/perf/util/hisi_ptt.h
>
On Thu, Apr 07, 2022 at 08:58:36PM +0800, Yicong Yang via iommu wrote:
> HiSilicon PCIe tune and trace device(PTT) is a PCIe Root Complex integrated
> Endpoint(RCiEP) device, providing the capability to dynamically monitor and
> tune the PCIe traffic, and trace the TLP headers.
>
> Add the driver for the device to enable the trace function. Register PMU
> device of PTT trace, then users can use trace through perf command. The
> driver makes use of perf AUX trace and support following events to
> configure the trace:
>
> - filter: select Root port or Endpoint to trace
> - type: select the type of traced TLP headers
> - direction: select the direction of traced TLP headers
> - format: select the data format of the traced TLP headers
>
> This patch adds the driver part of PTT trace. The perf command support of
> PTT trace is added in the following patch.
>
> Signed-off-by: Yicong Yang <[email protected]>
> Reviewed-by: Jonathan Cameron <[email protected]>
> ---
> drivers/Makefile | 1 +
> drivers/hwtracing/Kconfig | 2 +
> drivers/hwtracing/ptt/Kconfig | 12 +
> drivers/hwtracing/ptt/Makefile | 2 +
> drivers/hwtracing/ptt/hisi_ptt.c | 874 +++++++++++++++++++++++++++++++
> drivers/hwtracing/ptt/hisi_ptt.h | 166 ++++++
> 6 files changed, 1057 insertions(+)
> create mode 100644 drivers/hwtracing/ptt/Kconfig
> create mode 100644 drivers/hwtracing/ptt/Makefile
> create mode 100644 drivers/hwtracing/ptt/hisi_ptt.c
> create mode 100644 drivers/hwtracing/ptt/hisi_ptt.h
>
> diff --git a/drivers/Makefile b/drivers/Makefile
> index 020780b6b4d2..662d50599467 100644
> --- a/drivers/Makefile
> +++ b/drivers/Makefile
> @@ -175,6 +175,7 @@ obj-$(CONFIG_USB4) += thunderbolt/
> obj-$(CONFIG_CORESIGHT) += hwtracing/coresight/
> obj-y += hwtracing/intel_th/
> obj-$(CONFIG_STM) += hwtracing/stm/
> +obj-$(CONFIG_HISI_PTT) += hwtracing/ptt/
> obj-$(CONFIG_ANDROID) += android/
> obj-$(CONFIG_NVMEM) += nvmem/
> obj-$(CONFIG_FPGA) += fpga/
> diff --git a/drivers/hwtracing/Kconfig b/drivers/hwtracing/Kconfig
> index 13085835a636..911ee977103c 100644
> --- a/drivers/hwtracing/Kconfig
> +++ b/drivers/hwtracing/Kconfig
> @@ -5,4 +5,6 @@ source "drivers/hwtracing/stm/Kconfig"
>
> source "drivers/hwtracing/intel_th/Kconfig"
>
> +source "drivers/hwtracing/ptt/Kconfig"
> +
> endmenu
> diff --git a/drivers/hwtracing/ptt/Kconfig b/drivers/hwtracing/ptt/Kconfig
> new file mode 100644
> index 000000000000..8902a6f27563
> --- /dev/null
> +++ b/drivers/hwtracing/ptt/Kconfig
> @@ -0,0 +1,12 @@
> +# SPDX-License-Identifier: GPL-2.0-only
> +config HISI_PTT
> + tristate "HiSilicon PCIe Tune and Trace Device"
> + depends on ARM64 || (COMPILE_TEST && 64BIT)
> + depends on PCI && HAS_DMA && HAS_IOMEM && PERF_EVENTS
> + help
> + HiSilicon PCIe Tune and Trace Device exists as a PCIe RCiEP
> + device, and it provides support for PCIe traffic tuning and
> + tracing TLP headers to the memory.
> +
> + This driver can also be built as a module. If so, the module
> + will be called hisi_ptt.
> diff --git a/drivers/hwtracing/ptt/Makefile b/drivers/hwtracing/ptt/Makefile
> new file mode 100644
> index 000000000000..908c09a98161
> --- /dev/null
> +++ b/drivers/hwtracing/ptt/Makefile
> @@ -0,0 +1,2 @@
> +# SPDX-License-Identifier: GPL-2.0
> +obj-$(CONFIG_HISI_PTT) += hisi_ptt.o
> diff --git a/drivers/hwtracing/ptt/hisi_ptt.c b/drivers/hwtracing/ptt/hisi_ptt.c
> new file mode 100644
> index 000000000000..242b41870380
> --- /dev/null
> +++ b/drivers/hwtracing/ptt/hisi_ptt.c
> @@ -0,0 +1,874 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Driver for HiSilicon PCIe tune and trace device
> + *
> + * Copyright (c) 2022 HiSilicon Technologies Co., Ltd.
> + * Author: Yicong Yang <[email protected]>
> + */
> +
> +#include <linux/bitfield.h>
> +#include <linux/bitops.h>
> +#include <linux/delay.h>
> +#include <linux/dma-iommu.h>
> +#include <linux/dma-mapping.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/iommu.h>
> +#include <linux/iopoll.h>
> +#include <linux/module.h>
> +#include <linux/sysfs.h>
> +#include <linux/vmalloc.h>
> +
> +#include "hisi_ptt.h"
> +
> +static u16 hisi_ptt_get_filter_val(struct pci_dev *pdev)
> +{
> + if (pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT)
> + return BIT(HISI_PCIE_CORE_PORT_ID(PCI_SLOT(pdev->devfn)));
> +
> + return PCI_DEVID(pdev->bus->number, pdev->devfn);
> +}
> +
> +static bool hisi_ptt_wait_trace_hw_idle(struct hisi_ptt *hisi_ptt)
> +{
> + u32 val;
> +
> + return !readl_poll_timeout_atomic(hisi_ptt->iobase + HISI_PTT_TRACE_STS,
> + val, val & HISI_PTT_TRACE_IDLE,
> + HISI_PTT_WAIT_POLL_INTERVAL_US,
> + HISI_PTT_WAIT_TRACE_TIMEOUT_US);
> +}
> +
> +static bool hisi_ptt_wait_dma_reset_done(struct hisi_ptt *hisi_ptt)
> +{
> + u32 val;
> +
> + return !readl_poll_timeout_atomic(hisi_ptt->iobase + HISI_PTT_TRACE_WR_STS,
> + val, !val, HISI_PTT_RESET_POLL_INTERVAL_US,
> + HISI_PTT_RESET_TIMEOUT_US);
> +}
> +
> +static void hisi_ptt_free_trace_buf(struct hisi_ptt *hisi_ptt)
> +{
> + struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
> + struct device *dev = &hisi_ptt->pdev->dev;
> + int i;
> +
> + if (!ctrl->trace_buf)
> + return;
> +
> + for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; i++) {
> + if (ctrl->trace_buf[i].addr)
> + dmam_free_coherent(dev, HISI_PTT_TRACE_BUF_SIZE,
> + ctrl->trace_buf[i].addr,
> + ctrl->trace_buf[i].dma);
> + }
> +
> + devm_kfree(dev, ctrl->trace_buf);
> + ctrl->trace_buf = NULL;
> +}
> +
> +static int hisi_ptt_alloc_trace_buf(struct hisi_ptt *hisi_ptt)
> +{
> + struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
> + struct device *dev = &hisi_ptt->pdev->dev;
> + int i;
> +
> + hisi_ptt->trace_ctrl.buf_index = 0;
> +
> + /* If the trace buffer has already been allocated, zero it. */
> + if (ctrl->trace_buf) {
> + for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; i++)
> + memset(ctrl->trace_buf[i].addr, 0, HISI_PTT_TRACE_BUF_SIZE);
> + return 0;
> + }
> +
> + ctrl->trace_buf = devm_kcalloc(dev, HISI_PTT_TRACE_BUF_CNT,
> + sizeof(struct hisi_ptt_dma_buffer), GFP_KERNEL);
> + if (!ctrl->trace_buf)
> + return -ENOMEM;
> +
> + for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; ++i) {
> + ctrl->trace_buf[i].addr = dmam_alloc_coherent(dev, HISI_PTT_TRACE_BUF_SIZE,
> + &ctrl->trace_buf[i].dma,
> + GFP_KERNEL);
> + if (!ctrl->trace_buf[i].addr) {
> + hisi_ptt_free_trace_buf(hisi_ptt);
> + return -ENOMEM;
> + }
> + }
> +
> + return 0;
> +}
> +
> +static void hisi_ptt_trace_end(struct hisi_ptt *hisi_ptt)
> +{
> + writel(0, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
> + hisi_ptt->trace_ctrl.started = false;
> +}
> +
> +static int hisi_ptt_trace_start(struct hisi_ptt *hisi_ptt)
> +{
> + struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
> + u32 val;
> + int i;
> +
> + /* Check device idle before start trace */
> + if (!hisi_ptt_wait_trace_hw_idle(hisi_ptt)) {
> + pci_err(hisi_ptt->pdev, "Failed to start trace, the device is still busy\n");
> + return -EBUSY;
> + }
> +
> + ctrl->started = true;
> +
> + /* Reset the DMA before start tracing */
> + val = readl(hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
> + val |= HISI_PTT_TRACE_CTRL_RST;
> + writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
> +
> + hisi_ptt_wait_dma_reset_done(hisi_ptt);
> +
> + val = readl(hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
> + val &= ~HISI_PTT_TRACE_CTRL_RST;
> + writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
> +
> + /* Clear the interrupt status */
> + writel(HISI_PTT_TRACE_INT_STAT_MASK, hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
> + writel(0, hisi_ptt->iobase + HISI_PTT_TRACE_INT_MASK);
> +
> + /* Configure the trace DMA buffer */
> + for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; i++) {
> + writel(lower_32_bits(ctrl->trace_buf[i].dma),
> + hisi_ptt->iobase + HISI_PTT_TRACE_ADDR_BASE_LO_0 +
> + i * HISI_PTT_TRACE_ADDR_STRIDE);
> + writel(upper_32_bits(ctrl->trace_buf[i].dma),
> + hisi_ptt->iobase + HISI_PTT_TRACE_ADDR_BASE_HI_0 +
> + i * HISI_PTT_TRACE_ADDR_STRIDE);
> + }
> + writel(HISI_PTT_TRACE_BUF_SIZE, hisi_ptt->iobase + HISI_PTT_TRACE_ADDR_SIZE);
> +
> + /* Set the trace control register */
> + val = FIELD_PREP(HISI_PTT_TRACE_CTRL_TYPE_SEL, ctrl->type);
> + val |= FIELD_PREP(HISI_PTT_TRACE_CTRL_RXTX_SEL, ctrl->direction);
> + val |= FIELD_PREP(HISI_PTT_TRACE_CTRL_DATA_FORMAT, ctrl->format);
> + val |= FIELD_PREP(HISI_PTT_TRACE_CTRL_TARGET_SEL, hisi_ptt->trace_ctrl.filter);
> + if (!hisi_ptt->trace_ctrl.is_port)
> + val |= HISI_PTT_TRACE_CTRL_FILTER_MODE;
> +
> + /* Start the Trace */
> + val |= HISI_PTT_TRACE_CTRL_EN;
> + writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
> +
> + return 0;
> +}
> +
> +static int hisi_ptt_update_aux(struct hisi_ptt *hisi_ptt, int index, bool stop)
> +{
> + struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
> + struct perf_output_handle *handle = &ctrl->handle;
> + struct perf_event *event = handle->event;
> + struct hisi_ptt_pmu_buf *buf;
> + void *addr;
> +
> + buf = perf_get_aux(handle);
> + if (!buf || !handle->size)
> + return -EINVAL;
> +
> + addr = ctrl->trace_buf[ctrl->buf_index].addr;
> +
> + memcpy(buf->base + buf->pos, addr, HISI_PTT_TRACE_BUF_SIZE);
> + memset(addr, 0, HISI_PTT_TRACE_BUF_SIZE);
I am a bit worry buffer usages, at least for below aspects:
The first thing is for memset(), which cleans up the buffer and the
buffer size is 4MiB, this means it will consume much CPU time to
cleanup the buffer, and trace_buf is mapped as non-cacheable, the
performance would be get worse.
The second thing is here it always copies the trace data with size
HISI_PTT_TRACE_BUF_SIZE, usually, the trace module can provide a read
pointer register, so you can know the trace data length based on the
delta value between write and read pointers.
The last thing is the ctrl->trace_buf[] works as bounce buffer, so it
means actually there have an extra copy from bounce buffer to AUX
buffer, is it possible to directly output PTT trace data to AUX buffer?
Sorry if I bring up duplicate questions and before have the simliar
discussion when reviewed the patch.
> + buf->pos += HISI_PTT_TRACE_BUF_SIZE;
> +
> + if (stop) {
> + perf_aux_output_end(handle, buf->pos);
> + } else if (buf->length - buf->pos < HISI_PTT_TRACE_BUF_SIZE) {
> + perf_aux_output_skip(handle, buf->length - buf->pos);
> + perf_aux_output_end(handle, buf->pos);
> +
> + buf = perf_aux_output_begin(handle, event);
> + if (!buf)
> + return -EINVAL;
> +
> + buf->pos = handle->head % buf->length;
> + if (buf->length - buf->pos < HISI_PTT_TRACE_BUF_SIZE) {
> + perf_aux_output_end(handle, 0);
> + return -EINVAL;
> + }
> + }
> +
> + return 0;
> +}
> +
> +static irqreturn_t hisi_ptt_isr(int irq, void *context)
> +{
> + struct hisi_ptt *hisi_ptt = context;
> + u32 status, buf_idx;
> +
> + status = readl(hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
> + buf_idx = ffs(status) - 1;
> +
> + /* Clear the interrupt status of buffer @buf_idx */
> + writel(status, hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
> +
> + /*
> + * Update the AUX buffer and cache the current buffer index,
> + * as we need to know this and save the data when the trace
> + * is ended out of the interrupt handler. End the trace
> + * if the updating fails.
> + */
> + if (hisi_ptt_update_aux(hisi_ptt, buf_idx, false))
> + hisi_ptt_trace_end(hisi_ptt);
> + else
> + hisi_ptt->trace_ctrl.buf_index = (buf_idx + 1) % HISI_PTT_TRACE_BUF_CNT;
> +
> + return IRQ_HANDLED;
> +}
> +
> +static irqreturn_t hisi_ptt_irq(int irq, void *context)
> +{
> + struct hisi_ptt *hisi_ptt = context;
> + u32 status;
> +
> + status = readl(hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
> + if (!(status & HISI_PTT_TRACE_INT_STAT_MASK))
> + return IRQ_NONE;
> +
> + return IRQ_WAKE_THREAD;
> +}
> +
> +static void hisi_ptt_irq_free_vectors(void *pdev)
> +{
> + pci_free_irq_vectors(pdev);
> +}
> +
> +static int hisi_ptt_register_irq(struct hisi_ptt *hisi_ptt)
> +{
> + struct pci_dev *pdev = hisi_ptt->pdev;
> + int ret;
> +
> + ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSI);
> + if (ret < 0) {
> + pci_err(pdev, "failed to allocate irq vector, ret = %d\n", ret);
> + return ret;
> + }
> +
> + ret = devm_add_action_or_reset(&pdev->dev, hisi_ptt_irq_free_vectors, pdev);
> + if (ret < 0)
> + return ret;
> +
> + ret = devm_request_threaded_irq(&pdev->dev,
> + pci_irq_vector(pdev, HISI_PTT_TRACE_DMA_IRQ),
> + hisi_ptt_irq, hisi_ptt_isr, 0,
> + DRV_NAME, hisi_ptt);
> + if (ret) {
> + pci_err(pdev, "failed to request irq %d, ret = %d\n",
> + pci_irq_vector(pdev, HISI_PTT_TRACE_DMA_IRQ), ret);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int hisi_ptt_init_filters(struct pci_dev *pdev, void *data)
> +{
> + struct hisi_ptt_filter_desc *filter;
> + struct hisi_ptt *hisi_ptt = data;
> + struct list_head *target_list;
> +
> + target_list = pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT ?
> + &hisi_ptt->port_filters : &hisi_ptt->req_filters;
> +
> + filter = kzalloc(sizeof(*filter), GFP_KERNEL);
> + if (!filter) {
> + pci_err(hisi_ptt->pdev, "failed to add filter %s\n", pci_name(pdev));
> + return -ENOMEM;
> + }
> +
> + filter->pdev = pdev;
> + list_add_tail(&filter->list, target_list);
> +
> + /* Update the available port mask */
> + if (pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT)
> + hisi_ptt->port_mask |= hisi_ptt_get_filter_val(pdev);
> +
> + return 0;
> +}
> +
> +static void hisi_ptt_release_filters(void *data)
> +{
> + struct hisi_ptt_filter_desc *filter, *tfilter;
> + struct hisi_ptt *hisi_ptt = data;
> +
> + list_for_each_entry_safe(filter, tfilter, &hisi_ptt->req_filters, list) {
> + list_del(&filter->list);
> + kfree(filter);
> + }
> +
> + list_for_each_entry_safe(filter, tfilter, &hisi_ptt->port_filters, list) {
> + list_del(&filter->list);
> + kfree(filter);
> + }
> +}
> +
> +static int hisi_ptt_init_ctrls(struct hisi_ptt *hisi_ptt)
> +{
> + struct pci_dev *pdev = hisi_ptt->pdev;
> + struct pci_bus *bus;
> + int ret;
> + u32 reg;
> +
> + INIT_LIST_HEAD(&hisi_ptt->port_filters);
> + INIT_LIST_HEAD(&hisi_ptt->req_filters);
> +
> + /*
> + * The device range register provides the information about the
> + * root ports which the RCiEP can control and trace. The RCiEP
> + * and the root ports it support are on the same PCIe core, with
> + * same domain number but maybe different bus number. The device
> + * range register will tell us which root ports we can support,
> + * Bit[31:16] indicates the upper BDF numbers of the root port,
> + * while Bit[15:0] indicates the lower.
> + */
> + reg = readl(hisi_ptt->iobase + HISI_PTT_DEVICE_RANGE);
> + hisi_ptt->upper = FIELD_GET(HISI_PTT_DEVICE_RANGE_UPPER, reg);
> + hisi_ptt->lower = FIELD_GET(HISI_PTT_DEVICE_RANGE_LOWER, reg);
> +
> + bus = pci_find_bus(pci_domain_nr(pdev->bus), PCI_BUS_NUM(hisi_ptt->upper));
> + if (bus)
> + pci_walk_bus(bus, hisi_ptt_init_filters, hisi_ptt);
> +
> + ret = devm_add_action_or_reset(&pdev->dev, hisi_ptt_release_filters, hisi_ptt);
> + if (ret)
> + return ret;
> +
> + hisi_ptt->trace_ctrl.default_cpu = cpumask_first(cpumask_of_node(dev_to_node(&pdev->dev)));
> +
> + return 0;
> +}
> +
> +#define HISI_PTT_PMU_FILTER_IS_PORT BIT(19)
> +#define HISI_PTT_PMU_FILTER_VAL_MASK GENMASK(15, 0)
> +#define HISI_PTT_PMU_DIRECTION_MASK GENMASK(23, 20)
> +#define HISI_PTT_PMU_TYPE_MASK GENMASK(31, 24)
> +#define HISI_PTT_PMU_FORMAT_MASK GENMASK(35, 32)
> +
> +static ssize_t available_root_port_filters_show(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + struct hisi_ptt *hisi_ptt = to_hisi_ptt(dev_get_drvdata(dev));
> + struct hisi_ptt_filter_desc *filter;
> + int pos = 0;
> +
> + mutex_lock(&hisi_ptt->mutex);
> + if (list_empty(&hisi_ptt->port_filters)) {
> + pos = sysfs_emit(buf, "\n");
> + goto out;
> + }
> +
> + list_for_each_entry(filter, &hisi_ptt->port_filters, list)
> + pos += sysfs_emit_at(buf, pos, "%s 0x%05lx\n",
> + pci_name(filter->pdev),
> + hisi_ptt_get_filter_val(filter->pdev) |
> + HISI_PTT_PMU_FILTER_IS_PORT);
> +
> +out:
> + mutex_unlock(&hisi_ptt->mutex);
> + return pos;
> +}
> +static DEVICE_ATTR_ADMIN_RO(available_root_port_filters);
> +
> +static ssize_t available_requester_filters_show(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + struct hisi_ptt *hisi_ptt = to_hisi_ptt(dev_get_drvdata(dev));
> + struct hisi_ptt_filter_desc *filter;
> + int pos = 0;
> +
> + mutex_lock(&hisi_ptt->mutex);
> + if (list_empty(&hisi_ptt->req_filters)) {
> + pos = sysfs_emit(buf, "\n");
> + goto out;
> + }
> +
> + list_for_each_entry(filter, &hisi_ptt->req_filters, list)
> + pos += sysfs_emit_at(buf, pos, "%s 0x%05x\n",
> + pci_name(filter->pdev),
> + hisi_ptt_get_filter_val(filter->pdev));
> +
> +out:
> + mutex_unlock(&hisi_ptt->mutex);
> + return pos;
> +}
> +static DEVICE_ATTR_ADMIN_RO(available_requester_filters);
> +
> +PMU_FORMAT_ATTR(filter, "config:0-19");
> +PMU_FORMAT_ATTR(direction, "config:20-23");
> +PMU_FORMAT_ATTR(type, "config:24-31");
> +PMU_FORMAT_ATTR(format, "config:32-35");
> +
> +static struct attribute *hisi_ptt_pmu_format_attrs[] = {
> + &format_attr_filter.attr,
> + &format_attr_direction.attr,
> + &format_attr_type.attr,
> + &format_attr_format.attr,
> + NULL
> +};
> +
> +static struct attribute_group hisi_ptt_pmu_format_group = {
> + .name = "format",
> + .attrs = hisi_ptt_pmu_format_attrs,
> +};
> +
> +static struct attribute *hisi_ptt_pmu_filter_attrs[] = {
> + &dev_attr_available_root_port_filters.attr,
> + &dev_attr_available_requester_filters.attr,
> + NULL
> +};
> +
> +static struct attribute_group hisi_ptt_pmu_filter_group = {
> + .attrs = hisi_ptt_pmu_filter_attrs,
> +};
> +
> +static const struct attribute_group *hisi_ptt_pmu_groups[] = {
> + &hisi_ptt_pmu_format_group,
> + &hisi_ptt_pmu_filter_group,
> + NULL
> +};
> +
> +/*
> + * Check whether the config is valid or not. Some configs are multi-selectable
> + * and can be set simultaneously, while some are single selectable (onehot).
> + * Use this function to check the non-onehot configs while
> + * hisi_ptt_trace_valid_config_onehot() for the onehot ones.
> + */
> +static int hisi_ptt_trace_valid_config(u32 val, const u32 *available_list, u32 list_size)
> +{
> + int i;
> +
> + /* The non-onehot configs cannot be 0. */
> + if (!val)
> + return -EINVAL;
> +
> + /*
> + * Walk the available list and clear the valid bits of
> + * the config. If there is any resident bit after the
> + * walk then the config is invalid.
> + */
> + for (i = 0; i < list_size; i++)
> + val &= ~available_list[i];
> +
> + return val ? -EINVAL : 0;
> +}
> +
> +static int hisi_ptt_trace_valid_config_onehot(u32 val, const u32 *available_list, u32 list_size)
> +{
> + int i;
> +
> + for (i = 0; i < list_size; i++)
> + if (val == available_list[i])
> + return 0;
> +
> + return -EINVAL;
> +}
> +
> +static int hisi_ptt_trace_init_filter(struct hisi_ptt *hisi_ptt, u64 config)
> +{
> + unsigned long val, port_mask = hisi_ptt->port_mask;
> + struct hisi_ptt_filter_desc *filter;
> + int ret = -EINVAL;
> +
> + hisi_ptt->trace_ctrl.is_port = FIELD_GET(HISI_PTT_PMU_FILTER_IS_PORT, config);
> + val = FIELD_GET(HISI_PTT_PMU_FILTER_VAL_MASK, config);
> +
> + /*
> + * Port filters are defined as bit mask. For port filters, check
> + * the bits in the @val are within the range of hisi_ptt->port_mask
> + * and whether it's empty or not, otherwise user has specified
> + * some unsupported root ports.
> + *
> + * For Requester ID filters, walk the available filter list to see
> + * whether we have one matched.
> + */
> + if (!hisi_ptt->trace_ctrl.is_port) {
> + list_for_each_entry(filter, &hisi_ptt->req_filters, list)
> + if (val == hisi_ptt_get_filter_val(filter->pdev)) {
> + ret = 0;
> + break;
> + }
> + } else if (bitmap_subset(&val, &port_mask, BITS_PER_LONG)) {
> + ret = 0;
> + }
> +
> + if (ret)
> + return ret;
> +
> + hisi_ptt->trace_ctrl.filter = val;
> + return 0;
> +}
> +
> +static int hisi_ptt_pmu_event_init(struct perf_event *event)
> +{
> + /*
> + * The supported value of the direction parameter. See hisi_ptt.rst
> + * documentation for more details.
> + */
> + static const u32 hisi_ptt_trace_available_direction[] = {
> + 0,
> + 1,
> + 2,
> + 3,
> + };
> + /* Different types can be set simultaneously */
> + static const u32 hisi_ptt_trace_available_type[] = {
> + 1, /* posted_request */
> + 2, /* non-posted_request */
> + 4, /* completion */
> + };
> + static const u32 hisi_ptt_trace_availble_format[] = {
> + 0, /* 4DW */
> + 1, /* 8DW */
> + };
> + struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
> + struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
> + int ret;
> + u32 val;
> +
> + if (event->attr.type != hisi_ptt->hisi_ptt_pmu.type)
> + return -ENOENT;
Does PTT support per-task mode? Usually PMU not binding to CPU
cannot support per-task mode, if this is the case, please add checking
like below (copied code from arm_smmuv3_pmu.c):
if (event->cpu < 0) {
dev_dbg(dev, "Per-task mode not supported\n");
return -EOPNOTSUPP;
}
> +
> + mutex_lock(&hisi_ptt->mutex);
Here really need mutex for protection? I think the question can be
extended as "if the mutex is necessary for the whole driver"?
The reason is the perf core layer has provided the APIs
perf_event_ctx_lock() and perf_event_ctx_unlock() to protect event
context, and perf core layer has the mutex 'event->mmap_mutex' to
protect setup_aux().
Please note, I think init_event() callback is not protected by lock,
so you could see many PMU drivers use init_event() callback to
validate if the event parameters (e.g. if can work as group events
with other hardware events, support stack track, etc).
This means below initialise functions should be moved to add()
or setup_aux() callbacks, since these functions have been protected by
mutex in perf core layer.
> +
> + ret = hisi_ptt_trace_init_filter(hisi_ptt, event->attr.config);
> + if (ret < 0)
> + goto out;
> +
> + val = FIELD_GET(HISI_PTT_PMU_DIRECTION_MASK, event->attr.config);
> + ret = hisi_ptt_trace_valid_config_onehot(val, hisi_ptt_trace_available_direction,
> + ARRAY_SIZE(hisi_ptt_trace_available_direction));
> + if (ret < 0)
> + goto out;
> + ctrl->direction = val;
> +
> + val = FIELD_GET(HISI_PTT_PMU_TYPE_MASK, event->attr.config);
> + ret = hisi_ptt_trace_valid_config(val, hisi_ptt_trace_available_type,
> + ARRAY_SIZE(hisi_ptt_trace_available_type));
> + if (ret < 0)
> + goto out;
> + ctrl->type = val;
> +
> + val = FIELD_GET(HISI_PTT_PMU_FORMAT_MASK, event->attr.config);
> + ret = hisi_ptt_trace_valid_config_onehot(val, hisi_ptt_trace_availble_format,
> + ARRAY_SIZE(hisi_ptt_trace_availble_format));
> + if (ret < 0)
> + goto out;
> + ctrl->format = val;
> +
> +out:
> + mutex_unlock(&hisi_ptt->mutex);
> + return ret;
> +}
> +
> +static void *hisi_ptt_pmu_setup_aux(struct perf_event *event, void **pages,
> + int nr_pages, bool overwrite)
> +{
> + struct hisi_ptt_pmu_buf *buf;
> + struct page **pagelist;
> + int i;
> +
> + if (overwrite) {
> + dev_warn(event->pmu->dev, "Overwrite mode is not supported\n");
> + return NULL;
> + }
> +
> + /* If the pages size less than buffers, we cannot start trace */
> + if (nr_pages < HISI_PTT_TRACE_TOTAL_BUF_SIZE / PAGE_SIZE)
> + return NULL;
> +
> + buf = kzalloc(sizeof(*buf), GFP_KERNEL);
> + if (!buf)
> + return NULL;
> +
> + pagelist = kcalloc(nr_pages, sizeof(*pagelist), GFP_KERNEL);
> + if (!pagelist) {
> + kfree(buf);
> + return NULL;
> + }
> +
> + for (i = 0; i < nr_pages; i++)
> + pagelist[i] = virt_to_page(pages[i]);
> +
> + buf->base = vmap(pagelist, nr_pages, VM_MAP, PAGE_KERNEL);
> + if (!buf->base) {
> + kfree(pagelist);
> + kfree(buf);
> + return NULL;
> + }
> +
> + buf->nr_pages = nr_pages;
> + buf->length = nr_pages * PAGE_SIZE;
> + buf->pos = 0;
> +
> + kfree(pagelist);
> + return buf;
> +}
> +
> +static void hisi_ptt_pmu_free_aux(void *aux)
> +{
> + struct hisi_ptt_pmu_buf *buf = aux;
> +
> + vunmap(buf->base);
> + kfree(buf);
> +}
> +
> +static void hisi_ptt_pmu_start(struct perf_event *event, int flags)
> +{
> + struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
> + struct perf_output_handle *handle = &hisi_ptt->trace_ctrl.handle;
> + struct hw_perf_event *hwc = &event->hw;
> + struct hisi_ptt_pmu_buf *buf;
> + int cpu = event->cpu;
> + int ret;
> +
> + hwc->state = 0;
> + mutex_lock(&hisi_ptt->mutex);
> + if (hisi_ptt->trace_ctrl.started) {
> + pci_dbg(hisi_ptt->pdev, "trace has already started\n");
Essentialy this is not a PCI driver, it's good to use dev_dbg()
variant in the whole driver.
> + goto stop;
> + }
> +
> + if (cpu == -1)
> + cpu = hisi_ptt->trace_ctrl.default_cpu;
> +
> + /*
> + * Handle the interrupt on the same cpu which starts the trace to avoid
> + * context mismatch. Otherwise we'll trigger the WARN from the perf
> + * core in event_function_local().
> + */
> + WARN_ON(irq_set_affinity(pci_irq_vector(hisi_ptt->pdev, HISI_PTT_TRACE_DMA_IRQ),
> + cpumask_of(cpu)));
Nitpick: Can set the irq affinity in the probe phase? Seems to me,
the driver has enough info to set irq affinity in the probe phase,
it's not very necessary to defer to set irq affinity at here.
> +
> + ret = hisi_ptt_alloc_trace_buf(hisi_ptt);
> + if (ret) {
> + pci_dbg(hisi_ptt->pdev, "alloc trace buf failed, ret = %d\n", ret);
> + goto stop;
> + }
It's not a good idea to allocate buffer in the start(). The reason is
start() function might be invoked for multiple times in a perf
session. I understand the PTT driver doesn't support per-thread mode
and snapshot mode, so the start() callback will be not invoked for
multiple times, but you might need to consider if later support snapshot
mode.
I think it's better to move the buffer allocation into setup_aux().
Will continue to review the perf userspace patch.
Thanks,
Leo
> +
> + buf = perf_aux_output_begin(handle, event);
> + if (!buf) {
> + pci_dbg(hisi_ptt->pdev, "aux output begin failed\n");
> + goto stop;
> + }
> +
> + buf->pos = handle->head % buf->length;
> +
> + ret = hisi_ptt_trace_start(hisi_ptt);
> + if (ret) {
> + pci_dbg(hisi_ptt->pdev, "trace start failed, ret = %d\n", ret);
> + perf_aux_output_end(handle, 0);
> + goto stop;
> + }
> +
> + mutex_unlock(&hisi_ptt->mutex);
> + return;
> +stop:
> + event->hw.state |= PERF_HES_STOPPED;
> + mutex_unlock(&hisi_ptt->mutex);
> +}
> +
> +static void hisi_ptt_pmu_stop(struct perf_event *event, int flags)
> +{
> + struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
> + struct hw_perf_event *hwc = &event->hw;
> +
> + if (hwc->state & PERF_HES_STOPPED)
> + return;
> +
> + mutex_lock(&hisi_ptt->mutex);
> + if (hisi_ptt->trace_ctrl.started) {
> + hisi_ptt_trace_end(hisi_ptt);
> + WARN(!hisi_ptt_wait_trace_hw_idle(hisi_ptt), "Device is still busy");
> + hisi_ptt_update_aux(hisi_ptt, hisi_ptt->trace_ctrl.buf_index, true);
> + }
> + mutex_unlock(&hisi_ptt->mutex);
> +
> + hwc->state |= PERF_HES_STOPPED;
> + perf_event_update_userpage(event);
> + hwc->state |= PERF_HES_UPTODATE;
> +}
> +
> +static int hisi_ptt_pmu_add(struct perf_event *event, int flags)
> +{
> + struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
> + struct hw_perf_event *hwc = &event->hw;
> + int cpu = event->cpu;
> +
> + /*
> + * Only allow the default cpu to add the event if user doesn't specify
> + * the cpus.
> + */
> + if (cpu == -1 && smp_processor_id() != hisi_ptt->trace_ctrl.default_cpu)
> + return 0;
> +
> + hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE;
> +
> + if (flags & PERF_EF_START) {
> + hisi_ptt_pmu_start(event, PERF_EF_RELOAD);
> + if (hwc->state & PERF_HES_STOPPED)
> + return -EINVAL;
> + }
> +
> + return 0;
> +}
> +
> +static void hisi_ptt_pmu_del(struct perf_event *event, int flags)
> +{
> + hisi_ptt_pmu_stop(event, PERF_EF_UPDATE);
> +}
> +
> +static int hisi_ptt_register_pmu(struct hisi_ptt *hisi_ptt)
> +{
> + u16 core_id, sicl_id;
> + char *pmu_name;
> + u32 reg;
> +
> + hisi_ptt->hisi_ptt_pmu = (struct pmu) {
> + .module = THIS_MODULE,
> + .capabilities = PERF_PMU_CAP_EXCLUSIVE | PERF_PMU_CAP_ITRACE,
> + .task_ctx_nr = perf_sw_context,
> + .attr_groups = hisi_ptt_pmu_groups,
> + .event_init = hisi_ptt_pmu_event_init,
> + .setup_aux = hisi_ptt_pmu_setup_aux,
> + .free_aux = hisi_ptt_pmu_free_aux,
> + .start = hisi_ptt_pmu_start,
> + .stop = hisi_ptt_pmu_stop,
> + .add = hisi_ptt_pmu_add,
> + .del = hisi_ptt_pmu_del,
> + };
> +
> + reg = readl(hisi_ptt->iobase + HISI_PTT_LOCATION);
> + core_id = FIELD_GET(HISI_PTT_CORE_ID, reg);
> + sicl_id = FIELD_GET(HISI_PTT_SICL_ID, reg);
> +
> + pmu_name = devm_kasprintf(&hisi_ptt->pdev->dev, GFP_KERNEL, "hisi_ptt%u_%u",
> + sicl_id, core_id);
> + if (!pmu_name)
> + return -ENOMEM;
> +
> + return perf_pmu_register(&hisi_ptt->hisi_ptt_pmu, pmu_name, -1);
> +}
> +
> +/*
> + * The DMA of PTT trace can only use direct mapping, due to some
> + * hardware restriction. Check whether there is an IOMMU or the
> + * policy of the IOMMU domain is passthrough, otherwise the trace
> + * cannot work.
> + *
> + * The PTT device is supposed to behind the ARM SMMUv3, which
> + * should have passthrough the device by a quirk.
> + */
> +static int hisi_ptt_check_iommu_mapping(struct pci_dev *pdev)
> +{
> + struct iommu_domain *iommu_domain;
> +
> + iommu_domain = iommu_get_domain_for_dev(&pdev->dev);
> + if (!iommu_domain || iommu_domain->type == IOMMU_DOMAIN_IDENTITY)
> + return 0;
> +
> + return -EOPNOTSUPP;
> +}
> +
> +static int hisi_ptt_probe(struct pci_dev *pdev,
> + const struct pci_device_id *id)
> +{
> + struct hisi_ptt *hisi_ptt;
> + int ret;
> +
> + ret = hisi_ptt_check_iommu_mapping(pdev);
> + if (ret) {
> + pci_err(pdev, "requires direct DMA mappings\n");
> + return ret;
> + }
> +
> + hisi_ptt = devm_kzalloc(&pdev->dev, sizeof(*hisi_ptt), GFP_KERNEL);
> + if (!hisi_ptt)
> + return -ENOMEM;
> +
> + mutex_init(&hisi_ptt->mutex);
> + hisi_ptt->pdev = pdev;
> + pci_set_drvdata(pdev, hisi_ptt);
> +
> + ret = pcim_enable_device(pdev);
> + if (ret) {
> + pci_err(pdev, "failed to enable device, ret = %d\n", ret);
> + return ret;
> + }
> +
> + ret = pcim_iomap_regions(pdev, BIT(2), DRV_NAME);
> + if (ret) {
> + pci_err(pdev, "failed to remap io memory, ret = %d\n", ret);
> + return ret;
> + }
> +
> + hisi_ptt->iobase = pcim_iomap_table(pdev)[2];
> +
> + ret = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(64));
> + if (ret) {
> + pci_err(pdev, "failed to set 64 bit dma mask, ret = %d\n", ret);
> + return ret;
> + }
> +
> + pci_set_master(pdev);
> +
> + ret = hisi_ptt_register_irq(hisi_ptt);
> + if (ret)
> + return ret;
> +
> + ret = hisi_ptt_init_ctrls(hisi_ptt);
> + if (ret) {
> + pci_err(pdev, "failed to init controls, ret = %d\n", ret);
> + return ret;
> + }
> +
> + ret = hisi_ptt_register_pmu(hisi_ptt);
> + if (ret) {
> + pci_err(pdev, "failed to register PMU device, ret = %d", ret);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static void hisi_ptt_remove(struct pci_dev *pdev)
> +{
> + struct hisi_ptt *hisi_ptt = pci_get_drvdata(pdev);
> +
> + /*
> + * We have to manually unregister the PMU device rather than make it
> + * devres managed to keep order that the PMU device's unregistration
> + * is prior to the release of DMA buffers. As the DMA buffers are
> + * devm allocated when necessary which is after the registration of
> + * the PMU device.
> + */
> + perf_pmu_unregister(&hisi_ptt->hisi_ptt_pmu);
> +}
> +
> +static const struct pci_device_id hisi_ptt_id_tbl[] = {
> + { PCI_DEVICE(PCI_VENDOR_ID_HUAWEI, 0xa12e) },
> + { }
> +};
> +MODULE_DEVICE_TABLE(pci, hisi_ptt_id_tbl);
> +
> +static struct pci_driver hisi_ptt_driver = {
> + .name = DRV_NAME,
> + .id_table = hisi_ptt_id_tbl,
> + .probe = hisi_ptt_probe,
> + .remove = hisi_ptt_remove,
> +};
> +module_pci_driver(hisi_ptt_driver);
> +
> +MODULE_LICENSE("GPL");
> +MODULE_AUTHOR("Yicong Yang <[email protected]>");
> +MODULE_DESCRIPTION("Driver for HiSilicon PCIe tune and trace device");
> diff --git a/drivers/hwtracing/ptt/hisi_ptt.h b/drivers/hwtracing/ptt/hisi_ptt.h
> new file mode 100644
> index 000000000000..29b6d6293d6c
> --- /dev/null
> +++ b/drivers/hwtracing/ptt/hisi_ptt.h
> @@ -0,0 +1,166 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Driver for HiSilicon PCIe tune and trace device
> + *
> + * Copyright (c) 2022 HiSilicon Technologies Co., Ltd.
> + * Author: Yicong Yang <[email protected]>
> + */
> +
> +#ifndef _HISI_PTT_H
> +#define _HISI_PTT_H
> +
> +#include <linux/bits.h>
> +#include <linux/list.h>
> +#include <linux/mutex.h>
> +#include <linux/pci.h>
> +#include <linux/perf_event.h>
> +#include <linux/types.h>
> +
> +#define DRV_NAME "hisi_ptt"
> +
> +/*
> + * The definition of the device registers and register fields.
> + */
> +#define HISI_PTT_TRACE_ADDR_SIZE 0x0800
> +#define HISI_PTT_TRACE_ADDR_BASE_LO_0 0x0810
> +#define HISI_PTT_TRACE_ADDR_BASE_HI_0 0x0814
> +#define HISI_PTT_TRACE_ADDR_STRIDE 0x8
> +#define HISI_PTT_TRACE_CTRL 0x0850
> +#define HISI_PTT_TRACE_CTRL_EN BIT(0)
> +#define HISI_PTT_TRACE_CTRL_RST BIT(1)
> +#define HISI_PTT_TRACE_CTRL_RXTX_SEL GENMASK(3, 2)
> +#define HISI_PTT_TRACE_CTRL_TYPE_SEL GENMASK(7, 4)
> +#define HISI_PTT_TRACE_CTRL_DATA_FORMAT BIT(14)
> +#define HISI_PTT_TRACE_CTRL_FILTER_MODE BIT(15)
> +#define HISI_PTT_TRACE_CTRL_TARGET_SEL GENMASK(31, 16)
> +#define HISI_PTT_TRACE_INT_STAT 0x0890
> +#define HISI_PTT_TRACE_INT_STAT_MASK GENMASK(3, 0)
> +#define HISI_PTT_TRACE_INT_MASK 0x0894
> +#define HISI_PTT_TRACE_WR_STS 0x08a0
> +#define HISI_PTT_TRACE_WR_STS_WRITE GENMASK(27, 0)
> +#define HISI_PTT_TRACE_WR_STS_BUFFER GENMASK(29, 28)
> +#define HISI_PTT_TRACE_STS 0x08b0
> +#define HISI_PTT_TRACE_IDLE BIT(0)
> +#define HISI_PTT_DEVICE_RANGE 0x0fe0
> +#define HISI_PTT_DEVICE_RANGE_UPPER GENMASK(31, 16)
> +#define HISI_PTT_DEVICE_RANGE_LOWER GENMASK(15, 0)
> +#define HISI_PTT_LOCATION 0x0fe8
> +#define HISI_PTT_CORE_ID GENMASK(15, 0)
> +#define HISI_PTT_SICL_ID GENMASK(31, 16)
> +
> +/* Parameters of PTT trace DMA part. */
> +#define HISI_PTT_TRACE_DMA_IRQ 0
> +#define HISI_PTT_TRACE_BUF_CNT 4
> +#define HISI_PTT_TRACE_BUF_SIZE SZ_4M
> +#define HISI_PTT_TRACE_TOTAL_BUF_SIZE (HISI_PTT_TRACE_BUF_SIZE * \
> + HISI_PTT_TRACE_BUF_CNT)
> +/* Wait time for hardware DMA to reset */
> +#define HISI_PTT_RESET_TIMEOUT_US 10UL
> +#define HISI_PTT_RESET_POLL_INTERVAL_US 1UL
> +/* Poll timeout and interval for waiting hardware work to finish */
> +#define HISI_PTT_WAIT_TRACE_TIMEOUT_US 100UL
> +#define HISI_PTT_WAIT_POLL_INTERVAL_US 10UL
> +
> +#define HISI_PCIE_CORE_PORT_ID(devfn) (PCI_FUNC(devfn) << 1)
> +
> +/**
> + * struct hisi_ptt_dma_buffer - describe a single trace buffer of PTT trace.
> + * The detail of the data format is described
> + * in the documentation of PTT device.
> + * @dma: DMA address of this buffer visible to the device
> + * @addr: virtual address of this buffer visible to the cpu
> + */
> +struct hisi_ptt_dma_buffer {
> + dma_addr_t dma;
> + void *addr;
> +};
> +
> +/**
> + * struct hisi_ptt_trace_ctrl - control and status of PTT trace
> + * @trace_buf: array of the trace buffers for holding the trace data.
> + * the length will be HISI_PTT_TRACE_BUF_CNT.
> + * @handle: perf output handle of current trace session
> + * @default_cpu: default cpu to start the trace session
> + * @buf_index: the index of current using trace buffer
> + * @started: current trace status, true for started
> + * @is_port: whether we're tracing root port or not
> + * @direction: direction of the TLP headers to trace
> + * @filter: filter value for tracing the TLP headers
> + * @format: format of the TLP headers to trace
> + * @type: type of the TLP headers to trace
> + */
> +struct hisi_ptt_trace_ctrl {
> + struct hisi_ptt_dma_buffer *trace_buf;
> + struct perf_output_handle handle;
> + int default_cpu;
> + u32 buf_index;
> + bool started;
> + bool is_port;
> + u32 direction:2;
> + u32 filter:16;
> + u32 format:1;
> + u32 type:4;
> +};
> +
> +/**
> + * struct hisi_ptt_filter_desc - descriptor of the PTT trace filter
> + * @list: entry of this descriptor in the filter list
> + * @pdev: pci_dev related to this filter
> + */
> +struct hisi_ptt_filter_desc {
> + struct list_head list;
> + struct pci_dev *pdev;
> +};
> +
> +
> +/**
> + * struct hisi_ptt_pmu_buf - descriptor of the AUX buffer of PTT trace
> + * @length: size of the AUX buffer
> + * @nr_pages: number of pages of the AUX buffer
> + * @base: start address of AUX buffer
> + * @pos: position in the AUX buffer to commit traced data
> + */
> +struct hisi_ptt_pmu_buf {
> + size_t length;
> + int nr_pages;
> + void *base;
> + long pos;
> +};
> +
> +/**
> + * struct hisi_ptt - per PTT device data
> + * @trace_ctrl: the control information of PTT trace
> + * @hisi_ptt_pmu: the pum device of trace
> + * @iobase: base IO address of the device
> + * @pdev: pci_dev of this PTT device
> + * @mutex: mutex to protect the filter list and serialize the perf process.
> + * @upper: the upper BDF range of the PCI devices managed by this PTT device
> + * @lower: the lower BDF range of the PCI devices managed by this PTT device
> + * @port_filters: the filter list of root ports
> + * @req_filters: the filter list of requester ID
> + * @port_mask: port mask of the managed root ports
> + */
> +struct hisi_ptt {
> + struct hisi_ptt_trace_ctrl trace_ctrl;
> + struct pmu hisi_ptt_pmu;
> + void __iomem *iobase;
> + struct pci_dev *pdev;
> + struct mutex mutex;
> + u32 upper;
> + u32 lower;
> +
> + /*
> + * The trace TLP headers can either be filtered by certain
> + * root port, or by the requester ID. Organize the filters
> + * by @port_filters and @req_filters here. The mask of all
> + * the valid ports is also cached for doing sanity check
> + * of user input.
> + */
> + struct list_head port_filters;
> + struct list_head req_filters;
> + u16 port_mask;
> +};
> +
> +#define to_hisi_ptt(pmu) container_of(pmu, struct hisi_ptt, hisi_ptt_pmu)
> +
> +#endif /* _HISI_PTT_H */
> --
> 2.24.0
>
> _______________________________________________
> iommu mailing list
> [email protected]
> https://lists.linuxfoundation.org/mailman/listinfo/iommu
On 2022/5/10 17:46, James Clark wrote:
>
>
> On 07/04/2022 13:58, Yicong Yang wrote:
>> HiSilicon PCIe tune and trace device(PTT) is a PCIe Root Complex integrated
>> Endpoint(RCiEP) device, providing the capability to dynamically monitor and
>> tune the PCIe traffic, and trace the TLP headers.
>>
>> Add the driver for the device to enable the trace function. Register PMU
>> device of PTT trace, then users can use trace through perf command. The
>> driver makes use of perf AUX trace and support following events to
>> configure the trace:
>>
>> - filter: select Root port or Endpoint to trace
>> - type: select the type of traced TLP headers
>> - direction: select the direction of traced TLP headers
>> - format: select the data format of the traced TLP headers
>>
>> This patch adds the driver part of PTT trace. The perf command support of
>> PTT trace is added in the following patch.
>>
>> Signed-off-by: Yicong Yang <[email protected]>
>> Reviewed-by: Jonathan Cameron <[email protected]>
>> ---
>> drivers/Makefile | 1 +
>> drivers/hwtracing/Kconfig | 2 +
>> drivers/hwtracing/ptt/Kconfig | 12 +
>> drivers/hwtracing/ptt/Makefile | 2 +
>> drivers/hwtracing/ptt/hisi_ptt.c | 874 +++++++++++++++++++++++++++++++
>> drivers/hwtracing/ptt/hisi_ptt.h | 166 ++++++
>> 6 files changed, 1057 insertions(+)
>> create mode 100644 drivers/hwtracing/ptt/Kconfig
>> create mode 100644 drivers/hwtracing/ptt/Makefile
>> create mode 100644 drivers/hwtracing/ptt/hisi_ptt.c
>> create mode 100644 drivers/hwtracing/ptt/hisi_ptt.h
>>
>> diff --git a/drivers/Makefile b/drivers/Makefile
>> index 020780b6b4d2..662d50599467 100644
>> --- a/drivers/Makefile
>> +++ b/drivers/Makefile
>> @@ -175,6 +175,7 @@ obj-$(CONFIG_USB4) += thunderbolt/
>> obj-$(CONFIG_CORESIGHT) += hwtracing/coresight/
>> obj-y += hwtracing/intel_th/
>> obj-$(CONFIG_STM) += hwtracing/stm/
>> +obj-$(CONFIG_HISI_PTT) += hwtracing/ptt/
>> obj-$(CONFIG_ANDROID) += android/
>> obj-$(CONFIG_NVMEM) += nvmem/
>> obj-$(CONFIG_FPGA) += fpga/
>> diff --git a/drivers/hwtracing/Kconfig b/drivers/hwtracing/Kconfig
>> index 13085835a636..911ee977103c 100644
>> --- a/drivers/hwtracing/Kconfig
>> +++ b/drivers/hwtracing/Kconfig
>> @@ -5,4 +5,6 @@ source "drivers/hwtracing/stm/Kconfig"
>>
>> source "drivers/hwtracing/intel_th/Kconfig"
>>
>> +source "drivers/hwtracing/ptt/Kconfig"
>> +
>> endmenu
>> diff --git a/drivers/hwtracing/ptt/Kconfig b/drivers/hwtracing/ptt/Kconfig
>> new file mode 100644
>> index 000000000000..8902a6f27563
>> --- /dev/null
>> +++ b/drivers/hwtracing/ptt/Kconfig
>> @@ -0,0 +1,12 @@
>> +# SPDX-License-Identifier: GPL-2.0-only
>> +config HISI_PTT
>> + tristate "HiSilicon PCIe Tune and Trace Device"
>> + depends on ARM64 || (COMPILE_TEST && 64BIT)
>> + depends on PCI && HAS_DMA && HAS_IOMEM && PERF_EVENTS
>> + help
>> + HiSilicon PCIe Tune and Trace Device exists as a PCIe RCiEP
>> + device, and it provides support for PCIe traffic tuning and
>> + tracing TLP headers to the memory.
>> +
>> + This driver can also be built as a module. If so, the module
>> + will be called hisi_ptt.
>> diff --git a/drivers/hwtracing/ptt/Makefile b/drivers/hwtracing/ptt/Makefile
>> new file mode 100644
>> index 000000000000..908c09a98161
>> --- /dev/null
>> +++ b/drivers/hwtracing/ptt/Makefile
>> @@ -0,0 +1,2 @@
>> +# SPDX-License-Identifier: GPL-2.0
>> +obj-$(CONFIG_HISI_PTT) += hisi_ptt.o
>> diff --git a/drivers/hwtracing/ptt/hisi_ptt.c b/drivers/hwtracing/ptt/hisi_ptt.c
>> new file mode 100644
>> index 000000000000..242b41870380
>> --- /dev/null
>> +++ b/drivers/hwtracing/ptt/hisi_ptt.c
>> @@ -0,0 +1,874 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * Driver for HiSilicon PCIe tune and trace device
>> + *
>> + * Copyright (c) 2022 HiSilicon Technologies Co., Ltd.
>> + * Author: Yicong Yang <[email protected]>
>> + */
>> +
>> +#include <linux/bitfield.h>
>> +#include <linux/bitops.h>
>> +#include <linux/delay.h>
>> +#include <linux/dma-iommu.h>
>> +#include <linux/dma-mapping.h>
>> +#include <linux/interrupt.h>
>> +#include <linux/io.h>
>> +#include <linux/iommu.h>
>> +#include <linux/iopoll.h>
>> +#include <linux/module.h>
>> +#include <linux/sysfs.h>
>> +#include <linux/vmalloc.h>
>> +
>> +#include "hisi_ptt.h"
>> +
>> +static u16 hisi_ptt_get_filter_val(struct pci_dev *pdev)
>> +{
>> + if (pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT)
>> + return BIT(HISI_PCIE_CORE_PORT_ID(PCI_SLOT(pdev->devfn)));
>> +
>> + return PCI_DEVID(pdev->bus->number, pdev->devfn);
>> +}
>> +
>> +static bool hisi_ptt_wait_trace_hw_idle(struct hisi_ptt *hisi_ptt)
>> +{
>> + u32 val;
>> +
>> + return !readl_poll_timeout_atomic(hisi_ptt->iobase + HISI_PTT_TRACE_STS,
>> + val, val & HISI_PTT_TRACE_IDLE,
>> + HISI_PTT_WAIT_POLL_INTERVAL_US,
>> + HISI_PTT_WAIT_TRACE_TIMEOUT_US);
>> +}
>> +
>> +static bool hisi_ptt_wait_dma_reset_done(struct hisi_ptt *hisi_ptt)
>> +{
>> + u32 val;
>> +
>> + return !readl_poll_timeout_atomic(hisi_ptt->iobase + HISI_PTT_TRACE_WR_STS,
>> + val, !val, HISI_PTT_RESET_POLL_INTERVAL_US,
>> + HISI_PTT_RESET_TIMEOUT_US);
>> +}
>> +
>> +static void hisi_ptt_free_trace_buf(struct hisi_ptt *hisi_ptt)
>> +{
>> + struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
>> + struct device *dev = &hisi_ptt->pdev->dev;
>> + int i;
>> +
>> + if (!ctrl->trace_buf)
>> + return;
>> +
>> + for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; i++) {
>> + if (ctrl->trace_buf[i].addr)
>> + dmam_free_coherent(dev, HISI_PTT_TRACE_BUF_SIZE,
>> + ctrl->trace_buf[i].addr,
>> + ctrl->trace_buf[i].dma);
>> + }
>> +
>> + devm_kfree(dev, ctrl->trace_buf);
>> + ctrl->trace_buf = NULL;
>> +}
>> +
>> +static int hisi_ptt_alloc_trace_buf(struct hisi_ptt *hisi_ptt)
>> +{
>> + struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
>> + struct device *dev = &hisi_ptt->pdev->dev;
>> + int i;
>> +
>> + hisi_ptt->trace_ctrl.buf_index = 0;
>> +
>> + /* If the trace buffer has already been allocated, zero it. */
>> + if (ctrl->trace_buf) {
>> + for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; i++)
>> + memset(ctrl->trace_buf[i].addr, 0, HISI_PTT_TRACE_BUF_SIZE);
>> + return 0;
>> + }
>> +
>> + ctrl->trace_buf = devm_kcalloc(dev, HISI_PTT_TRACE_BUF_CNT,
>> + sizeof(struct hisi_ptt_dma_buffer), GFP_KERNEL);
>> + if (!ctrl->trace_buf)
>> + return -ENOMEM;
>> +
>> + for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; ++i) {
>> + ctrl->trace_buf[i].addr = dmam_alloc_coherent(dev, HISI_PTT_TRACE_BUF_SIZE,
>> + &ctrl->trace_buf[i].dma,
>> + GFP_KERNEL);
>> + if (!ctrl->trace_buf[i].addr) {
>> + hisi_ptt_free_trace_buf(hisi_ptt);
>> + return -ENOMEM;
>> + }
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +static void hisi_ptt_trace_end(struct hisi_ptt *hisi_ptt)
>> +{
>> + writel(0, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
>> + hisi_ptt->trace_ctrl.started = false;
>> +}
>> +
>> +static int hisi_ptt_trace_start(struct hisi_ptt *hisi_ptt)
>> +{
>> + struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
>> + u32 val;
>> + int i;
>> +
>> + /* Check device idle before start trace */
>> + if (!hisi_ptt_wait_trace_hw_idle(hisi_ptt)) {
>> + pci_err(hisi_ptt->pdev, "Failed to start trace, the device is still busy\n");
>> + return -EBUSY;
>> + }
>> +
>> + ctrl->started = true;
>> +
>> + /* Reset the DMA before start tracing */
>> + val = readl(hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
>> + val |= HISI_PTT_TRACE_CTRL_RST;
>> + writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
>> +
>> + hisi_ptt_wait_dma_reset_done(hisi_ptt);
>> +
>> + val = readl(hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
>> + val &= ~HISI_PTT_TRACE_CTRL_RST;
>> + writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
>> +
>> + /* Clear the interrupt status */
>> + writel(HISI_PTT_TRACE_INT_STAT_MASK, hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
>> + writel(0, hisi_ptt->iobase + HISI_PTT_TRACE_INT_MASK);
>> +
>> + /* Configure the trace DMA buffer */
>> + for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; i++) {
>> + writel(lower_32_bits(ctrl->trace_buf[i].dma),
>> + hisi_ptt->iobase + HISI_PTT_TRACE_ADDR_BASE_LO_0 +
>> + i * HISI_PTT_TRACE_ADDR_STRIDE);
>> + writel(upper_32_bits(ctrl->trace_buf[i].dma),
>> + hisi_ptt->iobase + HISI_PTT_TRACE_ADDR_BASE_HI_0 +
>> + i * HISI_PTT_TRACE_ADDR_STRIDE);
>> + }
>> + writel(HISI_PTT_TRACE_BUF_SIZE, hisi_ptt->iobase + HISI_PTT_TRACE_ADDR_SIZE);
>> +
>> + /* Set the trace control register */
>> + val = FIELD_PREP(HISI_PTT_TRACE_CTRL_TYPE_SEL, ctrl->type);
>> + val |= FIELD_PREP(HISI_PTT_TRACE_CTRL_RXTX_SEL, ctrl->direction);
>> + val |= FIELD_PREP(HISI_PTT_TRACE_CTRL_DATA_FORMAT, ctrl->format);
>> + val |= FIELD_PREP(HISI_PTT_TRACE_CTRL_TARGET_SEL, hisi_ptt->trace_ctrl.filter);
>> + if (!hisi_ptt->trace_ctrl.is_port)
>> + val |= HISI_PTT_TRACE_CTRL_FILTER_MODE;
>> +
>> + /* Start the Trace */
>> + val |= HISI_PTT_TRACE_CTRL_EN;
>> + writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
>> +
>> + return 0;
>> +}
>> +
>> +static int hisi_ptt_update_aux(struct hisi_ptt *hisi_ptt, int index, bool stop)
>> +{
>> + struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
>> + struct perf_output_handle *handle = &ctrl->handle;
>> + struct perf_event *event = handle->event;
>> + struct hisi_ptt_pmu_buf *buf;
>> + void *addr;
>> +
>> + buf = perf_get_aux(handle);
>> + if (!buf || !handle->size)
>> + return -EINVAL;
>> +
>> + addr = ctrl->trace_buf[ctrl->buf_index].addr;
>> +
>> + memcpy(buf->base + buf->pos, addr, HISI_PTT_TRACE_BUF_SIZE);
>> + memset(addr, 0, HISI_PTT_TRACE_BUF_SIZE);
>
> Hi Kicong,
>
> I also have the same comment as Leo here, I don't think the memset is
> required.
>
It's necessary in the current approach as we always commit HISI_PTT_TRACE_BUF_SIZE
data but the buffer maybe partly filled (called when perf going to stopp, not by the
interrupt). The buffer is cleared so the unfilled part of the buffer will have
empty data (normal traced TLP headers won't be all 0), then the user can distinguish
the valid part of the data.
I'm trying to only copy the traced data rather than the whole buffer then the
clear operation here will be unnecessary. The hardware provide a register indicating
which offset of which buffer it's currently writing to and it canbe used here.
>> + buf->pos += HISI_PTT_TRACE_BUF_SIZE;
>> +
>> + if (stop) {
>> + perf_aux_output_end(handle, buf->pos);
>> + } else if (buf->length - buf->pos < HISI_PTT_TRACE_BUF_SIZE) {
>> + perf_aux_output_skip(handle, buf->length - buf->pos);
>
> perf_aux_output_skip() can also return an error so should probably also
> be checked like perf_aux_output_begin()
>
ok it should be checked.
> I'm also wondering why there is a skip for every output_end()? Is that
> to avoid having two memcpy calls to handle the wrap around if the data
> to be copied goes past the end of the aux buffer?
>
> For example if your buffers are 4MB each and the aux buffer that the
> user picked isn't a multiple of 4 I can see you needing to write the
> first part of the 4MB to the end of the aux buffer and then the last
> part to the beginning which would be two memcpy() calls. And then a
> skip wouldn't be required.
>
I intended to handle the case that AUX buffer is not a multiple of 4 MiB.
When the resident AUX buffer size is less than 4MiB, we're not going to
commit data to it and will apply a new AUX buffer instead. I think you're
right that the perf_aux_output_skip() is unnecessary here. Thanks for
catching this.
> I looked at all the other uses of perf_output_end() and perf_output_skip()
> in the kernel and didn't see a pattern like yours so it seems suspicous to
> me. Maybe at least some comments around this section are needed.
>
Will add some comments of the handling here.
Regards,
Yicong
On Thu, Apr 07, 2022 at 08:58:35PM +0800, Yicong Yang wrote:
> The DMA operations of HiSilicon PTT device can only work properly with
> identical mappings. So add a quirk for the device to force the domain
> as passthrough.
>
> Signed-off-by: Yicong Yang <[email protected]>
> ---
> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 16 ++++++++++++++++
> 1 file changed, 16 insertions(+)
I still don't like this being part of the SMMU driver, but given that
(a) Robin doesn't seem to agree with the objection and (b) you've been
refreshing the patch series:
Acked-by: Will Deacon <[email protected]>
If you do respin, then:
> diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> index 627a3ed5ee8f..5ec15ae2a9b1 100644
> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> @@ -2839,6 +2839,21 @@ static int arm_smmu_dev_disable_feature(struct device *dev,
> }
> }
It might be worth adding a brief comment here to explain what this device is
and why it needs an identity mapping.
> +#define IS_HISI_PTT_DEVICE(pdev) ((pdev)->vendor == PCI_VENDOR_ID_HUAWEI && \
> + (pdev)->device == 0xa12e)
Will
On 07/04/2022 13:58, Yicong Yang wrote:
> HiSilicon PCIe tune and trace device(PTT) is a PCIe Root Complex integrated
> Endpoint(RCiEP) device, providing the capability to dynamically monitor and
> tune the PCIe traffic, and trace the TLP headers.
>
> Add the driver for the device to enable the trace function. Register PMU
> device of PTT trace, then users can use trace through perf command. The
> driver makes use of perf AUX trace and support following events to
> configure the trace:
>
> - filter: select Root port or Endpoint to trace
> - type: select the type of traced TLP headers
> - direction: select the direction of traced TLP headers
> - format: select the data format of the traced TLP headers
>
> This patch adds the driver part of PTT trace. The perf command support of
> PTT trace is added in the following patch.
>
> Signed-off-by: Yicong Yang <[email protected]>
> Reviewed-by: Jonathan Cameron <[email protected]>
> ---
> drivers/Makefile | 1 +
> drivers/hwtracing/Kconfig | 2 +
> drivers/hwtracing/ptt/Kconfig | 12 +
> drivers/hwtracing/ptt/Makefile | 2 +
> drivers/hwtracing/ptt/hisi_ptt.c | 874 +++++++++++++++++++++++++++++++
> drivers/hwtracing/ptt/hisi_ptt.h | 166 ++++++
> 6 files changed, 1057 insertions(+)
> create mode 100644 drivers/hwtracing/ptt/Kconfig
> create mode 100644 drivers/hwtracing/ptt/Makefile
> create mode 100644 drivers/hwtracing/ptt/hisi_ptt.c
> create mode 100644 drivers/hwtracing/ptt/hisi_ptt.h
>
> diff --git a/drivers/Makefile b/drivers/Makefile
> index 020780b6b4d2..662d50599467 100644
> --- a/drivers/Makefile
> +++ b/drivers/Makefile
> @@ -175,6 +175,7 @@ obj-$(CONFIG_USB4) += thunderbolt/
> obj-$(CONFIG_CORESIGHT) += hwtracing/coresight/
> obj-y += hwtracing/intel_th/
> obj-$(CONFIG_STM) += hwtracing/stm/
> +obj-$(CONFIG_HISI_PTT) += hwtracing/ptt/
> obj-$(CONFIG_ANDROID) += android/
> obj-$(CONFIG_NVMEM) += nvmem/
> obj-$(CONFIG_FPGA) += fpga/
> diff --git a/drivers/hwtracing/Kconfig b/drivers/hwtracing/Kconfig
> index 13085835a636..911ee977103c 100644
> --- a/drivers/hwtracing/Kconfig
> +++ b/drivers/hwtracing/Kconfig
> @@ -5,4 +5,6 @@ source "drivers/hwtracing/stm/Kconfig"
>
> source "drivers/hwtracing/intel_th/Kconfig"
>
> +source "drivers/hwtracing/ptt/Kconfig"
> +
> endmenu
> diff --git a/drivers/hwtracing/ptt/Kconfig b/drivers/hwtracing/ptt/Kconfig
> new file mode 100644
> index 000000000000..8902a6f27563
> --- /dev/null
> +++ b/drivers/hwtracing/ptt/Kconfig
> @@ -0,0 +1,12 @@
> +# SPDX-License-Identifier: GPL-2.0-only
> +config HISI_PTT
> + tristate "HiSilicon PCIe Tune and Trace Device"
> + depends on ARM64 || (COMPILE_TEST && 64BIT)
> + depends on PCI && HAS_DMA && HAS_IOMEM && PERF_EVENTS
> + help
> + HiSilicon PCIe Tune and Trace Device exists as a PCIe RCiEP
> + device, and it provides support for PCIe traffic tuning and
> + tracing TLP headers to the memory.
> +
> + This driver can also be built as a module. If so, the module
> + will be called hisi_ptt.
> diff --git a/drivers/hwtracing/ptt/Makefile b/drivers/hwtracing/ptt/Makefile
> new file mode 100644
> index 000000000000..908c09a98161
> --- /dev/null
> +++ b/drivers/hwtracing/ptt/Makefile
> @@ -0,0 +1,2 @@
> +# SPDX-License-Identifier: GPL-2.0
> +obj-$(CONFIG_HISI_PTT) += hisi_ptt.o
> diff --git a/drivers/hwtracing/ptt/hisi_ptt.c b/drivers/hwtracing/ptt/hisi_ptt.c
> new file mode 100644
> index 000000000000..242b41870380
> --- /dev/null
> +++ b/drivers/hwtracing/ptt/hisi_ptt.c
> @@ -0,0 +1,874 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Driver for HiSilicon PCIe tune and trace device
> + *
> + * Copyright (c) 2022 HiSilicon Technologies Co., Ltd.
> + * Author: Yicong Yang <[email protected]>
> + */
> +
> +#include <linux/bitfield.h>
> +#include <linux/bitops.h>
> +#include <linux/delay.h>
> +#include <linux/dma-iommu.h>
> +#include <linux/dma-mapping.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/iommu.h>
> +#include <linux/iopoll.h>
> +#include <linux/module.h>
> +#include <linux/sysfs.h>
> +#include <linux/vmalloc.h>
> +
> +#include "hisi_ptt.h"
> +
> +static u16 hisi_ptt_get_filter_val(struct pci_dev *pdev)
> +{
> + if (pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT)
> + return BIT(HISI_PCIE_CORE_PORT_ID(PCI_SLOT(pdev->devfn)));
> +
> + return PCI_DEVID(pdev->bus->number, pdev->devfn);
> +}
> +
> +static bool hisi_ptt_wait_trace_hw_idle(struct hisi_ptt *hisi_ptt)
> +{
> + u32 val;
> +
> + return !readl_poll_timeout_atomic(hisi_ptt->iobase + HISI_PTT_TRACE_STS,
> + val, val & HISI_PTT_TRACE_IDLE,
> + HISI_PTT_WAIT_POLL_INTERVAL_US,
> + HISI_PTT_WAIT_TRACE_TIMEOUT_US);
> +}
> +
> +static bool hisi_ptt_wait_dma_reset_done(struct hisi_ptt *hisi_ptt)
> +{
> + u32 val;
> +
> + return !readl_poll_timeout_atomic(hisi_ptt->iobase + HISI_PTT_TRACE_WR_STS,
> + val, !val, HISI_PTT_RESET_POLL_INTERVAL_US,
> + HISI_PTT_RESET_TIMEOUT_US);
> +}
> +
> +static void hisi_ptt_free_trace_buf(struct hisi_ptt *hisi_ptt)
> +{
> + struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
> + struct device *dev = &hisi_ptt->pdev->dev;
> + int i;
> +
> + if (!ctrl->trace_buf)
> + return;
> +
> + for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; i++) {
> + if (ctrl->trace_buf[i].addr)
> + dmam_free_coherent(dev, HISI_PTT_TRACE_BUF_SIZE,
> + ctrl->trace_buf[i].addr,
> + ctrl->trace_buf[i].dma);
> + }
> +
> + devm_kfree(dev, ctrl->trace_buf);
> + ctrl->trace_buf = NULL;
> +}
> +
> +static int hisi_ptt_alloc_trace_buf(struct hisi_ptt *hisi_ptt)
> +{
> + struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
> + struct device *dev = &hisi_ptt->pdev->dev;
> + int i;
> +
> + hisi_ptt->trace_ctrl.buf_index = 0;
> +
> + /* If the trace buffer has already been allocated, zero it. */
> + if (ctrl->trace_buf) {
> + for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; i++)
> + memset(ctrl->trace_buf[i].addr, 0, HISI_PTT_TRACE_BUF_SIZE);
> + return 0;
> + }
> +
> + ctrl->trace_buf = devm_kcalloc(dev, HISI_PTT_TRACE_BUF_CNT,
> + sizeof(struct hisi_ptt_dma_buffer), GFP_KERNEL);
> + if (!ctrl->trace_buf)
> + return -ENOMEM;
> +
> + for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; ++i) {
> + ctrl->trace_buf[i].addr = dmam_alloc_coherent(dev, HISI_PTT_TRACE_BUF_SIZE,
> + &ctrl->trace_buf[i].dma,
> + GFP_KERNEL);
> + if (!ctrl->trace_buf[i].addr) {
> + hisi_ptt_free_trace_buf(hisi_ptt);
> + return -ENOMEM;
> + }
> + }
> +
> + return 0;
> +}
> +
> +static void hisi_ptt_trace_end(struct hisi_ptt *hisi_ptt)
> +{
> + writel(0, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
> + hisi_ptt->trace_ctrl.started = false;
> +}
> +
> +static int hisi_ptt_trace_start(struct hisi_ptt *hisi_ptt)
> +{
> + struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
> + u32 val;
> + int i;
> +
> + /* Check device idle before start trace */
> + if (!hisi_ptt_wait_trace_hw_idle(hisi_ptt)) {
> + pci_err(hisi_ptt->pdev, "Failed to start trace, the device is still busy\n");
> + return -EBUSY;
> + }
> +
> + ctrl->started = true;
> +
> + /* Reset the DMA before start tracing */
> + val = readl(hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
> + val |= HISI_PTT_TRACE_CTRL_RST;
> + writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
> +
> + hisi_ptt_wait_dma_reset_done(hisi_ptt);
> +
> + val = readl(hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
> + val &= ~HISI_PTT_TRACE_CTRL_RST;
> + writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
> +
> + /* Clear the interrupt status */
> + writel(HISI_PTT_TRACE_INT_STAT_MASK, hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
> + writel(0, hisi_ptt->iobase + HISI_PTT_TRACE_INT_MASK);
> +
> + /* Configure the trace DMA buffer */
> + for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; i++) {
> + writel(lower_32_bits(ctrl->trace_buf[i].dma),
> + hisi_ptt->iobase + HISI_PTT_TRACE_ADDR_BASE_LO_0 +
> + i * HISI_PTT_TRACE_ADDR_STRIDE);
> + writel(upper_32_bits(ctrl->trace_buf[i].dma),
> + hisi_ptt->iobase + HISI_PTT_TRACE_ADDR_BASE_HI_0 +
> + i * HISI_PTT_TRACE_ADDR_STRIDE);
> + }
> + writel(HISI_PTT_TRACE_BUF_SIZE, hisi_ptt->iobase + HISI_PTT_TRACE_ADDR_SIZE);
> +
> + /* Set the trace control register */
> + val = FIELD_PREP(HISI_PTT_TRACE_CTRL_TYPE_SEL, ctrl->type);
> + val |= FIELD_PREP(HISI_PTT_TRACE_CTRL_RXTX_SEL, ctrl->direction);
> + val |= FIELD_PREP(HISI_PTT_TRACE_CTRL_DATA_FORMAT, ctrl->format);
> + val |= FIELD_PREP(HISI_PTT_TRACE_CTRL_TARGET_SEL, hisi_ptt->trace_ctrl.filter);
> + if (!hisi_ptt->trace_ctrl.is_port)
> + val |= HISI_PTT_TRACE_CTRL_FILTER_MODE;
> +
> + /* Start the Trace */
> + val |= HISI_PTT_TRACE_CTRL_EN;
> + writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
> +
> + return 0;
> +}
> +
> +static int hisi_ptt_update_aux(struct hisi_ptt *hisi_ptt, int index, bool stop)
> +{
> + struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
> + struct perf_output_handle *handle = &ctrl->handle;
> + struct perf_event *event = handle->event;
> + struct hisi_ptt_pmu_buf *buf;
> + void *addr;
> +
> + buf = perf_get_aux(handle);
> + if (!buf || !handle->size)
> + return -EINVAL;
> +
> + addr = ctrl->trace_buf[ctrl->buf_index].addr;
> +
> + memcpy(buf->base + buf->pos, addr, HISI_PTT_TRACE_BUF_SIZE);
> + memset(addr, 0, HISI_PTT_TRACE_BUF_SIZE);
Hi Kicong,
I also have the same comment as Leo here, I don't think the memset is
required.
> + buf->pos += HISI_PTT_TRACE_BUF_SIZE;
> +
> + if (stop) {
> + perf_aux_output_end(handle, buf->pos);
> + } else if (buf->length - buf->pos < HISI_PTT_TRACE_BUF_SIZE) {
> + perf_aux_output_skip(handle, buf->length - buf->pos);
perf_aux_output_skip() can also return an error so should probably also
be checked like perf_aux_output_begin()
I'm also wondering why there is a skip for every output_end()? Is that
to avoid having two memcpy calls to handle the wrap around if the data
to be copied goes past the end of the aux buffer?
For example if your buffers are 4MB each and the aux buffer that the
user picked isn't a multiple of 4 I can see you needing to write the
first part of the 4MB to the end of the aux buffer and then the last
part to the beginning which would be two memcpy() calls. And then a
skip wouldn't be required.
I looked at all the other uses of perf_output_end() and perf_output_skip()
in the kernel and didn't see a pattern like yours so it seems suspicous to
me. Maybe at least some comments around this section are needed.
Thanks
James
> + perf_aux_output_end(handle, buf->pos);
> +
> + buf = perf_aux_output_begin(handle, event);
> + if (!buf)
> + return -EINVAL;
> +
> + buf->pos = handle->head % buf->length;
> + if (buf->length - buf->pos < HISI_PTT_TRACE_BUF_SIZE) {
> + perf_aux_output_end(handle, 0);
> + return -EINVAL;
> + }
> + }
> +
> + return 0;
> +}
> +
> +static irqreturn_t hisi_ptt_isr(int irq, void *context)
> +{
> + struct hisi_ptt *hisi_ptt = context;
> + u32 status, buf_idx;
> +
> + status = readl(hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
> + buf_idx = ffs(status) - 1;
> +
> + /* Clear the interrupt status of buffer @buf_idx */
> + writel(status, hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
> +
> + /*
> + * Update the AUX buffer and cache the current buffer index,
> + * as we need to know this and save the data when the trace
> + * is ended out of the interrupt handler. End the trace
> + * if the updating fails.
> + */
> + if (hisi_ptt_update_aux(hisi_ptt, buf_idx, false))
> + hisi_ptt_trace_end(hisi_ptt);
> + else
> + hisi_ptt->trace_ctrl.buf_index = (buf_idx + 1) % HISI_PTT_TRACE_BUF_CNT;
> +
> + return IRQ_HANDLED;
> +}
> +
> +static irqreturn_t hisi_ptt_irq(int irq, void *context)
> +{
> + struct hisi_ptt *hisi_ptt = context;
> + u32 status;
> +
> + status = readl(hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
> + if (!(status & HISI_PTT_TRACE_INT_STAT_MASK))
> + return IRQ_NONE;
> +
> + return IRQ_WAKE_THREAD;
> +}
> +
> +static void hisi_ptt_irq_free_vectors(void *pdev)
> +{
> + pci_free_irq_vectors(pdev);
> +}
> +
> +static int hisi_ptt_register_irq(struct hisi_ptt *hisi_ptt)
> +{
> + struct pci_dev *pdev = hisi_ptt->pdev;
> + int ret;
> +
> + ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSI);
> + if (ret < 0) {
> + pci_err(pdev, "failed to allocate irq vector, ret = %d\n", ret);
> + return ret;
> + }
> +
> + ret = devm_add_action_or_reset(&pdev->dev, hisi_ptt_irq_free_vectors, pdev);
> + if (ret < 0)
> + return ret;
> +
> + ret = devm_request_threaded_irq(&pdev->dev,
> + pci_irq_vector(pdev, HISI_PTT_TRACE_DMA_IRQ),
> + hisi_ptt_irq, hisi_ptt_isr, 0,
> + DRV_NAME, hisi_ptt);
> + if (ret) {
> + pci_err(pdev, "failed to request irq %d, ret = %d\n",
> + pci_irq_vector(pdev, HISI_PTT_TRACE_DMA_IRQ), ret);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int hisi_ptt_init_filters(struct pci_dev *pdev, void *data)
> +{
> + struct hisi_ptt_filter_desc *filter;
> + struct hisi_ptt *hisi_ptt = data;
> + struct list_head *target_list;
> +
> + target_list = pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT ?
> + &hisi_ptt->port_filters : &hisi_ptt->req_filters;
> +
> + filter = kzalloc(sizeof(*filter), GFP_KERNEL);
> + if (!filter) {
> + pci_err(hisi_ptt->pdev, "failed to add filter %s\n", pci_name(pdev));
> + return -ENOMEM;
> + }
> +
> + filter->pdev = pdev;
> + list_add_tail(&filter->list, target_list);
> +
> + /* Update the available port mask */
> + if (pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT)
> + hisi_ptt->port_mask |= hisi_ptt_get_filter_val(pdev);
> +
> + return 0;
> +}
> +
> +static void hisi_ptt_release_filters(void *data)
> +{
> + struct hisi_ptt_filter_desc *filter, *tfilter;
> + struct hisi_ptt *hisi_ptt = data;
> +
> + list_for_each_entry_safe(filter, tfilter, &hisi_ptt->req_filters, list) {
> + list_del(&filter->list);
> + kfree(filter);
> + }
> +
> + list_for_each_entry_safe(filter, tfilter, &hisi_ptt->port_filters, list) {
> + list_del(&filter->list);
> + kfree(filter);
> + }
> +}
> +
> +static int hisi_ptt_init_ctrls(struct hisi_ptt *hisi_ptt)
> +{
> + struct pci_dev *pdev = hisi_ptt->pdev;
> + struct pci_bus *bus;
> + int ret;
> + u32 reg;
> +
> + INIT_LIST_HEAD(&hisi_ptt->port_filters);
> + INIT_LIST_HEAD(&hisi_ptt->req_filters);
> +
> + /*
> + * The device range register provides the information about the
> + * root ports which the RCiEP can control and trace. The RCiEP
> + * and the root ports it support are on the same PCIe core, with
> + * same domain number but maybe different bus number. The device
> + * range register will tell us which root ports we can support,
> + * Bit[31:16] indicates the upper BDF numbers of the root port,
> + * while Bit[15:0] indicates the lower.
> + */
> + reg = readl(hisi_ptt->iobase + HISI_PTT_DEVICE_RANGE);
> + hisi_ptt->upper = FIELD_GET(HISI_PTT_DEVICE_RANGE_UPPER, reg);
> + hisi_ptt->lower = FIELD_GET(HISI_PTT_DEVICE_RANGE_LOWER, reg);
> +
> + bus = pci_find_bus(pci_domain_nr(pdev->bus), PCI_BUS_NUM(hisi_ptt->upper));
> + if (bus)
> + pci_walk_bus(bus, hisi_ptt_init_filters, hisi_ptt);
> +
> + ret = devm_add_action_or_reset(&pdev->dev, hisi_ptt_release_filters, hisi_ptt);
> + if (ret)
> + return ret;
> +
> + hisi_ptt->trace_ctrl.default_cpu = cpumask_first(cpumask_of_node(dev_to_node(&pdev->dev)));
> +
> + return 0;
> +}
> +
> +#define HISI_PTT_PMU_FILTER_IS_PORT BIT(19)
> +#define HISI_PTT_PMU_FILTER_VAL_MASK GENMASK(15, 0)
> +#define HISI_PTT_PMU_DIRECTION_MASK GENMASK(23, 20)
> +#define HISI_PTT_PMU_TYPE_MASK GENMASK(31, 24)
> +#define HISI_PTT_PMU_FORMAT_MASK GENMASK(35, 32)
> +
> +static ssize_t available_root_port_filters_show(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + struct hisi_ptt *hisi_ptt = to_hisi_ptt(dev_get_drvdata(dev));
> + struct hisi_ptt_filter_desc *filter;
> + int pos = 0;
> +
> + mutex_lock(&hisi_ptt->mutex);
> + if (list_empty(&hisi_ptt->port_filters)) {
> + pos = sysfs_emit(buf, "\n");
> + goto out;
> + }
> +
> + list_for_each_entry(filter, &hisi_ptt->port_filters, list)
> + pos += sysfs_emit_at(buf, pos, "%s 0x%05lx\n",
> + pci_name(filter->pdev),
> + hisi_ptt_get_filter_val(filter->pdev) |
> + HISI_PTT_PMU_FILTER_IS_PORT);
> +
> +out:
> + mutex_unlock(&hisi_ptt->mutex);
> + return pos;
> +}
> +static DEVICE_ATTR_ADMIN_RO(available_root_port_filters);
> +
> +static ssize_t available_requester_filters_show(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + struct hisi_ptt *hisi_ptt = to_hisi_ptt(dev_get_drvdata(dev));
> + struct hisi_ptt_filter_desc *filter;
> + int pos = 0;
> +
> + mutex_lock(&hisi_ptt->mutex);
> + if (list_empty(&hisi_ptt->req_filters)) {
> + pos = sysfs_emit(buf, "\n");
> + goto out;
> + }
> +
> + list_for_each_entry(filter, &hisi_ptt->req_filters, list)
> + pos += sysfs_emit_at(buf, pos, "%s 0x%05x\n",
> + pci_name(filter->pdev),
> + hisi_ptt_get_filter_val(filter->pdev));
> +
> +out:
> + mutex_unlock(&hisi_ptt->mutex);
> + return pos;
> +}
> +static DEVICE_ATTR_ADMIN_RO(available_requester_filters);
> +
> +PMU_FORMAT_ATTR(filter, "config:0-19");
> +PMU_FORMAT_ATTR(direction, "config:20-23");
> +PMU_FORMAT_ATTR(type, "config:24-31");
> +PMU_FORMAT_ATTR(format, "config:32-35");
> +
> +static struct attribute *hisi_ptt_pmu_format_attrs[] = {
> + &format_attr_filter.attr,
> + &format_attr_direction.attr,
> + &format_attr_type.attr,
> + &format_attr_format.attr,
> + NULL
> +};
> +
> +static struct attribute_group hisi_ptt_pmu_format_group = {
> + .name = "format",
> + .attrs = hisi_ptt_pmu_format_attrs,
> +};
> +
> +static struct attribute *hisi_ptt_pmu_filter_attrs[] = {
> + &dev_attr_available_root_port_filters.attr,
> + &dev_attr_available_requester_filters.attr,
> + NULL
> +};
> +
> +static struct attribute_group hisi_ptt_pmu_filter_group = {
> + .attrs = hisi_ptt_pmu_filter_attrs,
> +};
> +
> +static const struct attribute_group *hisi_ptt_pmu_groups[] = {
> + &hisi_ptt_pmu_format_group,
> + &hisi_ptt_pmu_filter_group,
> + NULL
> +};
> +
> +/*
> + * Check whether the config is valid or not. Some configs are multi-selectable
> + * and can be set simultaneously, while some are single selectable (onehot).
> + * Use this function to check the non-onehot configs while
> + * hisi_ptt_trace_valid_config_onehot() for the onehot ones.
> + */
> +static int hisi_ptt_trace_valid_config(u32 val, const u32 *available_list, u32 list_size)
> +{
> + int i;
> +
> + /* The non-onehot configs cannot be 0. */
> + if (!val)
> + return -EINVAL;
> +
> + /*
> + * Walk the available list and clear the valid bits of
> + * the config. If there is any resident bit after the
> + * walk then the config is invalid.
> + */
> + for (i = 0; i < list_size; i++)
> + val &= ~available_list[i];
> +
> + return val ? -EINVAL : 0;
> +}
> +
> +static int hisi_ptt_trace_valid_config_onehot(u32 val, const u32 *available_list, u32 list_size)
> +{
> + int i;
> +
> + for (i = 0; i < list_size; i++)
> + if (val == available_list[i])
> + return 0;
> +
> + return -EINVAL;
> +}
> +
> +static int hisi_ptt_trace_init_filter(struct hisi_ptt *hisi_ptt, u64 config)
> +{
> + unsigned long val, port_mask = hisi_ptt->port_mask;
> + struct hisi_ptt_filter_desc *filter;
> + int ret = -EINVAL;
> +
> + hisi_ptt->trace_ctrl.is_port = FIELD_GET(HISI_PTT_PMU_FILTER_IS_PORT, config);
> + val = FIELD_GET(HISI_PTT_PMU_FILTER_VAL_MASK, config);
> +
> + /*
> + * Port filters are defined as bit mask. For port filters, check
> + * the bits in the @val are within the range of hisi_ptt->port_mask
> + * and whether it's empty or not, otherwise user has specified
> + * some unsupported root ports.
> + *
> + * For Requester ID filters, walk the available filter list to see
> + * whether we have one matched.
> + */
> + if (!hisi_ptt->trace_ctrl.is_port) {
> + list_for_each_entry(filter, &hisi_ptt->req_filters, list)
> + if (val == hisi_ptt_get_filter_val(filter->pdev)) {
> + ret = 0;
> + break;
> + }
> + } else if (bitmap_subset(&val, &port_mask, BITS_PER_LONG)) {
> + ret = 0;
> + }
> +
> + if (ret)
> + return ret;
> +
> + hisi_ptt->trace_ctrl.filter = val;
> + return 0;
> +}
> +
> +static int hisi_ptt_pmu_event_init(struct perf_event *event)
> +{
> + /*
> + * The supported value of the direction parameter. See hisi_ptt.rst
> + * documentation for more details.
> + */
> + static const u32 hisi_ptt_trace_available_direction[] = {
> + 0,
> + 1,
> + 2,
> + 3,
> + };
> + /* Different types can be set simultaneously */
> + static const u32 hisi_ptt_trace_available_type[] = {
> + 1, /* posted_request */
> + 2, /* non-posted_request */
> + 4, /* completion */
> + };
> + static const u32 hisi_ptt_trace_availble_format[] = {
> + 0, /* 4DW */
> + 1, /* 8DW */
> + };
> + struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
> + struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
> + int ret;
> + u32 val;
> +
> + if (event->attr.type != hisi_ptt->hisi_ptt_pmu.type)
> + return -ENOENT;
> +
> + mutex_lock(&hisi_ptt->mutex);
> +
> + ret = hisi_ptt_trace_init_filter(hisi_ptt, event->attr.config);
> + if (ret < 0)
> + goto out;
> +
> + val = FIELD_GET(HISI_PTT_PMU_DIRECTION_MASK, event->attr.config);
> + ret = hisi_ptt_trace_valid_config_onehot(val, hisi_ptt_trace_available_direction,
> + ARRAY_SIZE(hisi_ptt_trace_available_direction));
> + if (ret < 0)
> + goto out;
> + ctrl->direction = val;
> +
> + val = FIELD_GET(HISI_PTT_PMU_TYPE_MASK, event->attr.config);
> + ret = hisi_ptt_trace_valid_config(val, hisi_ptt_trace_available_type,
> + ARRAY_SIZE(hisi_ptt_trace_available_type));
> + if (ret < 0)
> + goto out;
> + ctrl->type = val;
> +
> + val = FIELD_GET(HISI_PTT_PMU_FORMAT_MASK, event->attr.config);
> + ret = hisi_ptt_trace_valid_config_onehot(val, hisi_ptt_trace_availble_format,
> + ARRAY_SIZE(hisi_ptt_trace_availble_format));
> + if (ret < 0)
> + goto out;
> + ctrl->format = val;
> +
> +out:
> + mutex_unlock(&hisi_ptt->mutex);
> + return ret;
> +}
> +
> +static void *hisi_ptt_pmu_setup_aux(struct perf_event *event, void **pages,
> + int nr_pages, bool overwrite)
> +{
> + struct hisi_ptt_pmu_buf *buf;
> + struct page **pagelist;
> + int i;
> +
> + if (overwrite) {
> + dev_warn(event->pmu->dev, "Overwrite mode is not supported\n");
> + return NULL;
> + }
> +
> + /* If the pages size less than buffers, we cannot start trace */
> + if (nr_pages < HISI_PTT_TRACE_TOTAL_BUF_SIZE / PAGE_SIZE)
> + return NULL;
> +
> + buf = kzalloc(sizeof(*buf), GFP_KERNEL);
> + if (!buf)
> + return NULL;
> +
> + pagelist = kcalloc(nr_pages, sizeof(*pagelist), GFP_KERNEL);
> + if (!pagelist) {
> + kfree(buf);
> + return NULL;
> + }
> +
> + for (i = 0; i < nr_pages; i++)
> + pagelist[i] = virt_to_page(pages[i]);
> +
> + buf->base = vmap(pagelist, nr_pages, VM_MAP, PAGE_KERNEL);
> + if (!buf->base) {
> + kfree(pagelist);
> + kfree(buf);
> + return NULL;
> + }
> +
> + buf->nr_pages = nr_pages;
> + buf->length = nr_pages * PAGE_SIZE;
> + buf->pos = 0;
> +
> + kfree(pagelist);
> + return buf;
> +}
> +
> +static void hisi_ptt_pmu_free_aux(void *aux)
> +{
> + struct hisi_ptt_pmu_buf *buf = aux;
> +
> + vunmap(buf->base);
> + kfree(buf);
> +}
> +
> +static void hisi_ptt_pmu_start(struct perf_event *event, int flags)
> +{
> + struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
> + struct perf_output_handle *handle = &hisi_ptt->trace_ctrl.handle;
> + struct hw_perf_event *hwc = &event->hw;
> + struct hisi_ptt_pmu_buf *buf;
> + int cpu = event->cpu;
> + int ret;
> +
> + hwc->state = 0;
> + mutex_lock(&hisi_ptt->mutex);
> + if (hisi_ptt->trace_ctrl.started) {
> + pci_dbg(hisi_ptt->pdev, "trace has already started\n");
> + goto stop;
> + }
> +
> + if (cpu == -1)
> + cpu = hisi_ptt->trace_ctrl.default_cpu;
> +
> + /*
> + * Handle the interrupt on the same cpu which starts the trace to avoid
> + * context mismatch. Otherwise we'll trigger the WARN from the perf
> + * core in event_function_local().
> + */
> + WARN_ON(irq_set_affinity(pci_irq_vector(hisi_ptt->pdev, HISI_PTT_TRACE_DMA_IRQ),
> + cpumask_of(cpu)));
> +
> + ret = hisi_ptt_alloc_trace_buf(hisi_ptt);
> + if (ret) {
> + pci_dbg(hisi_ptt->pdev, "alloc trace buf failed, ret = %d\n", ret);
> + goto stop;
> + }
> +
> + buf = perf_aux_output_begin(handle, event);
> + if (!buf) {
> + pci_dbg(hisi_ptt->pdev, "aux output begin failed\n");
> + goto stop;
> + }
> +
> + buf->pos = handle->head % buf->length;
> +
> + ret = hisi_ptt_trace_start(hisi_ptt);
> + if (ret) {
> + pci_dbg(hisi_ptt->pdev, "trace start failed, ret = %d\n", ret);
> + perf_aux_output_end(handle, 0);
> + goto stop;
> + }
> +
> + mutex_unlock(&hisi_ptt->mutex);
> + return;
> +stop:
> + event->hw.state |= PERF_HES_STOPPED;
> + mutex_unlock(&hisi_ptt->mutex);
> +}
> +
> +static void hisi_ptt_pmu_stop(struct perf_event *event, int flags)
> +{
> + struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
> + struct hw_perf_event *hwc = &event->hw;
> +
> + if (hwc->state & PERF_HES_STOPPED)
> + return;
> +
> + mutex_lock(&hisi_ptt->mutex);
> + if (hisi_ptt->trace_ctrl.started) {
> + hisi_ptt_trace_end(hisi_ptt);
> + WARN(!hisi_ptt_wait_trace_hw_idle(hisi_ptt), "Device is still busy");
> + hisi_ptt_update_aux(hisi_ptt, hisi_ptt->trace_ctrl.buf_index, true);
> + }
> + mutex_unlock(&hisi_ptt->mutex);
> +
> + hwc->state |= PERF_HES_STOPPED;
> + perf_event_update_userpage(event);
> + hwc->state |= PERF_HES_UPTODATE;
> +}
> +
> +static int hisi_ptt_pmu_add(struct perf_event *event, int flags)
> +{
> + struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
> + struct hw_perf_event *hwc = &event->hw;
> + int cpu = event->cpu;
> +
> + /*
> + * Only allow the default cpu to add the event if user doesn't specify
> + * the cpus.
> + */
> + if (cpu == -1 && smp_processor_id() != hisi_ptt->trace_ctrl.default_cpu)
> + return 0;
> +
> + hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE;
> +
> + if (flags & PERF_EF_START) {
> + hisi_ptt_pmu_start(event, PERF_EF_RELOAD);
> + if (hwc->state & PERF_HES_STOPPED)
> + return -EINVAL;
> + }
> +
> + return 0;
> +}
> +
> +static void hisi_ptt_pmu_del(struct perf_event *event, int flags)
> +{
> + hisi_ptt_pmu_stop(event, PERF_EF_UPDATE);
> +}
> +
> +static int hisi_ptt_register_pmu(struct hisi_ptt *hisi_ptt)
> +{
> + u16 core_id, sicl_id;
> + char *pmu_name;
> + u32 reg;
> +
> + hisi_ptt->hisi_ptt_pmu = (struct pmu) {
> + .module = THIS_MODULE,
> + .capabilities = PERF_PMU_CAP_EXCLUSIVE | PERF_PMU_CAP_ITRACE,
> + .task_ctx_nr = perf_sw_context,
> + .attr_groups = hisi_ptt_pmu_groups,
> + .event_init = hisi_ptt_pmu_event_init,
> + .setup_aux = hisi_ptt_pmu_setup_aux,
> + .free_aux = hisi_ptt_pmu_free_aux,
> + .start = hisi_ptt_pmu_start,
> + .stop = hisi_ptt_pmu_stop,
> + .add = hisi_ptt_pmu_add,
> + .del = hisi_ptt_pmu_del,
> + };
> +
> + reg = readl(hisi_ptt->iobase + HISI_PTT_LOCATION);
> + core_id = FIELD_GET(HISI_PTT_CORE_ID, reg);
> + sicl_id = FIELD_GET(HISI_PTT_SICL_ID, reg);
> +
> + pmu_name = devm_kasprintf(&hisi_ptt->pdev->dev, GFP_KERNEL, "hisi_ptt%u_%u",
> + sicl_id, core_id);
> + if (!pmu_name)
> + return -ENOMEM;
> +
> + return perf_pmu_register(&hisi_ptt->hisi_ptt_pmu, pmu_name, -1);
> +}
> +
> +/*
> + * The DMA of PTT trace can only use direct mapping, due to some
> + * hardware restriction. Check whether there is an IOMMU or the
> + * policy of the IOMMU domain is passthrough, otherwise the trace
> + * cannot work.
> + *
> + * The PTT device is supposed to behind the ARM SMMUv3, which
> + * should have passthrough the device by a quirk.
> + */
> +static int hisi_ptt_check_iommu_mapping(struct pci_dev *pdev)
> +{
> + struct iommu_domain *iommu_domain;
> +
> + iommu_domain = iommu_get_domain_for_dev(&pdev->dev);
> + if (!iommu_domain || iommu_domain->type == IOMMU_DOMAIN_IDENTITY)
> + return 0;
> +
> + return -EOPNOTSUPP;
> +}
> +
> +static int hisi_ptt_probe(struct pci_dev *pdev,
> + const struct pci_device_id *id)
> +{
> + struct hisi_ptt *hisi_ptt;
> + int ret;
> +
> + ret = hisi_ptt_check_iommu_mapping(pdev);
> + if (ret) {
> + pci_err(pdev, "requires direct DMA mappings\n");
> + return ret;
> + }
> +
> + hisi_ptt = devm_kzalloc(&pdev->dev, sizeof(*hisi_ptt), GFP_KERNEL);
> + if (!hisi_ptt)
> + return -ENOMEM;
> +
> + mutex_init(&hisi_ptt->mutex);
> + hisi_ptt->pdev = pdev;
> + pci_set_drvdata(pdev, hisi_ptt);
> +
> + ret = pcim_enable_device(pdev);
> + if (ret) {
> + pci_err(pdev, "failed to enable device, ret = %d\n", ret);
> + return ret;
> + }
> +
> + ret = pcim_iomap_regions(pdev, BIT(2), DRV_NAME);
> + if (ret) {
> + pci_err(pdev, "failed to remap io memory, ret = %d\n", ret);
> + return ret;
> + }
> +
> + hisi_ptt->iobase = pcim_iomap_table(pdev)[2];
> +
> + ret = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(64));
> + if (ret) {
> + pci_err(pdev, "failed to set 64 bit dma mask, ret = %d\n", ret);
> + return ret;
> + }
> +
> + pci_set_master(pdev);
> +
> + ret = hisi_ptt_register_irq(hisi_ptt);
> + if (ret)
> + return ret;
> +
> + ret = hisi_ptt_init_ctrls(hisi_ptt);
> + if (ret) {
> + pci_err(pdev, "failed to init controls, ret = %d\n", ret);
> + return ret;
> + }
> +
> + ret = hisi_ptt_register_pmu(hisi_ptt);
> + if (ret) {
> + pci_err(pdev, "failed to register PMU device, ret = %d", ret);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static void hisi_ptt_remove(struct pci_dev *pdev)
> +{
> + struct hisi_ptt *hisi_ptt = pci_get_drvdata(pdev);
> +
> + /*
> + * We have to manually unregister the PMU device rather than make it
> + * devres managed to keep order that the PMU device's unregistration
> + * is prior to the release of DMA buffers. As the DMA buffers are
> + * devm allocated when necessary which is after the registration of
> + * the PMU device.
> + */
> + perf_pmu_unregister(&hisi_ptt->hisi_ptt_pmu);
> +}
> +
> +static const struct pci_device_id hisi_ptt_id_tbl[] = {
> + { PCI_DEVICE(PCI_VENDOR_ID_HUAWEI, 0xa12e) },
> + { }
> +};
> +MODULE_DEVICE_TABLE(pci, hisi_ptt_id_tbl);
> +
> +static struct pci_driver hisi_ptt_driver = {
> + .name = DRV_NAME,
> + .id_table = hisi_ptt_id_tbl,
> + .probe = hisi_ptt_probe,
> + .remove = hisi_ptt_remove,
> +};
> +module_pci_driver(hisi_ptt_driver);
> +
> +MODULE_LICENSE("GPL");
> +MODULE_AUTHOR("Yicong Yang <[email protected]>");
> +MODULE_DESCRIPTION("Driver for HiSilicon PCIe tune and trace device");
> diff --git a/drivers/hwtracing/ptt/hisi_ptt.h b/drivers/hwtracing/ptt/hisi_ptt.h
> new file mode 100644
> index 000000000000..29b6d6293d6c
> --- /dev/null
> +++ b/drivers/hwtracing/ptt/hisi_ptt.h
> @@ -0,0 +1,166 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Driver for HiSilicon PCIe tune and trace device
> + *
> + * Copyright (c) 2022 HiSilicon Technologies Co., Ltd.
> + * Author: Yicong Yang <[email protected]>
> + */
> +
> +#ifndef _HISI_PTT_H
> +#define _HISI_PTT_H
> +
> +#include <linux/bits.h>
> +#include <linux/list.h>
> +#include <linux/mutex.h>
> +#include <linux/pci.h>
> +#include <linux/perf_event.h>
> +#include <linux/types.h>
> +
> +#define DRV_NAME "hisi_ptt"
> +
> +/*
> + * The definition of the device registers and register fields.
> + */
> +#define HISI_PTT_TRACE_ADDR_SIZE 0x0800
> +#define HISI_PTT_TRACE_ADDR_BASE_LO_0 0x0810
> +#define HISI_PTT_TRACE_ADDR_BASE_HI_0 0x0814
> +#define HISI_PTT_TRACE_ADDR_STRIDE 0x8
> +#define HISI_PTT_TRACE_CTRL 0x0850
> +#define HISI_PTT_TRACE_CTRL_EN BIT(0)
> +#define HISI_PTT_TRACE_CTRL_RST BIT(1)
> +#define HISI_PTT_TRACE_CTRL_RXTX_SEL GENMASK(3, 2)
> +#define HISI_PTT_TRACE_CTRL_TYPE_SEL GENMASK(7, 4)
> +#define HISI_PTT_TRACE_CTRL_DATA_FORMAT BIT(14)
> +#define HISI_PTT_TRACE_CTRL_FILTER_MODE BIT(15)
> +#define HISI_PTT_TRACE_CTRL_TARGET_SEL GENMASK(31, 16)
> +#define HISI_PTT_TRACE_INT_STAT 0x0890
> +#define HISI_PTT_TRACE_INT_STAT_MASK GENMASK(3, 0)
> +#define HISI_PTT_TRACE_INT_MASK 0x0894
> +#define HISI_PTT_TRACE_WR_STS 0x08a0
> +#define HISI_PTT_TRACE_WR_STS_WRITE GENMASK(27, 0)
> +#define HISI_PTT_TRACE_WR_STS_BUFFER GENMASK(29, 28)
> +#define HISI_PTT_TRACE_STS 0x08b0
> +#define HISI_PTT_TRACE_IDLE BIT(0)
> +#define HISI_PTT_DEVICE_RANGE 0x0fe0
> +#define HISI_PTT_DEVICE_RANGE_UPPER GENMASK(31, 16)
> +#define HISI_PTT_DEVICE_RANGE_LOWER GENMASK(15, 0)
> +#define HISI_PTT_LOCATION 0x0fe8
> +#define HISI_PTT_CORE_ID GENMASK(15, 0)
> +#define HISI_PTT_SICL_ID GENMASK(31, 16)
> +
> +/* Parameters of PTT trace DMA part. */
> +#define HISI_PTT_TRACE_DMA_IRQ 0
> +#define HISI_PTT_TRACE_BUF_CNT 4
> +#define HISI_PTT_TRACE_BUF_SIZE SZ_4M
> +#define HISI_PTT_TRACE_TOTAL_BUF_SIZE (HISI_PTT_TRACE_BUF_SIZE * \
> + HISI_PTT_TRACE_BUF_CNT)
> +/* Wait time for hardware DMA to reset */
> +#define HISI_PTT_RESET_TIMEOUT_US 10UL
> +#define HISI_PTT_RESET_POLL_INTERVAL_US 1UL
> +/* Poll timeout and interval for waiting hardware work to finish */
> +#define HISI_PTT_WAIT_TRACE_TIMEOUT_US 100UL
> +#define HISI_PTT_WAIT_POLL_INTERVAL_US 10UL
> +
> +#define HISI_PCIE_CORE_PORT_ID(devfn) (PCI_FUNC(devfn) << 1)
> +
> +/**
> + * struct hisi_ptt_dma_buffer - describe a single trace buffer of PTT trace.
> + * The detail of the data format is described
> + * in the documentation of PTT device.
> + * @dma: DMA address of this buffer visible to the device
> + * @addr: virtual address of this buffer visible to the cpu
> + */
> +struct hisi_ptt_dma_buffer {
> + dma_addr_t dma;
> + void *addr;
> +};
> +
> +/**
> + * struct hisi_ptt_trace_ctrl - control and status of PTT trace
> + * @trace_buf: array of the trace buffers for holding the trace data.
> + * the length will be HISI_PTT_TRACE_BUF_CNT.
> + * @handle: perf output handle of current trace session
> + * @default_cpu: default cpu to start the trace session
> + * @buf_index: the index of current using trace buffer
> + * @started: current trace status, true for started
> + * @is_port: whether we're tracing root port or not
> + * @direction: direction of the TLP headers to trace
> + * @filter: filter value for tracing the TLP headers
> + * @format: format of the TLP headers to trace
> + * @type: type of the TLP headers to trace
> + */
> +struct hisi_ptt_trace_ctrl {
> + struct hisi_ptt_dma_buffer *trace_buf;
> + struct perf_output_handle handle;
> + int default_cpu;
> + u32 buf_index;
> + bool started;
> + bool is_port;
> + u32 direction:2;
> + u32 filter:16;
> + u32 format:1;
> + u32 type:4;
> +};
> +
> +/**
> + * struct hisi_ptt_filter_desc - descriptor of the PTT trace filter
> + * @list: entry of this descriptor in the filter list
> + * @pdev: pci_dev related to this filter
> + */
> +struct hisi_ptt_filter_desc {
> + struct list_head list;
> + struct pci_dev *pdev;
> +};
> +
> +
> +/**
> + * struct hisi_ptt_pmu_buf - descriptor of the AUX buffer of PTT trace
> + * @length: size of the AUX buffer
> + * @nr_pages: number of pages of the AUX buffer
> + * @base: start address of AUX buffer
> + * @pos: position in the AUX buffer to commit traced data
> + */
> +struct hisi_ptt_pmu_buf {
> + size_t length;
> + int nr_pages;
> + void *base;
> + long pos;
> +};
> +
> +/**
> + * struct hisi_ptt - per PTT device data
> + * @trace_ctrl: the control information of PTT trace
> + * @hisi_ptt_pmu: the pum device of trace
> + * @iobase: base IO address of the device
> + * @pdev: pci_dev of this PTT device
> + * @mutex: mutex to protect the filter list and serialize the perf process.
> + * @upper: the upper BDF range of the PCI devices managed by this PTT device
> + * @lower: the lower BDF range of the PCI devices managed by this PTT device
> + * @port_filters: the filter list of root ports
> + * @req_filters: the filter list of requester ID
> + * @port_mask: port mask of the managed root ports
> + */
> +struct hisi_ptt {
> + struct hisi_ptt_trace_ctrl trace_ctrl;
> + struct pmu hisi_ptt_pmu;
> + void __iomem *iobase;
> + struct pci_dev *pdev;
> + struct mutex mutex;
> + u32 upper;
> + u32 lower;
> +
> + /*
> + * The trace TLP headers can either be filtered by certain
> + * root port, or by the requester ID. Organize the filters
> + * by @port_filters and @req_filters here. The mask of all
> + * the valid ports is also cached for doing sanity check
> + * of user input.
> + */
> + struct list_head port_filters;
> + struct list_head req_filters;
> + u16 port_mask;
> +};
> +
> +#define to_hisi_ptt(pmu) container_of(pmu, struct hisi_ptt, hisi_ptt_pmu)
> +
> +#endif /* _HISI_PTT_H */
On 2022/5/10 19:23, Will Deacon wrote:
> On Thu, Apr 07, 2022 at 08:58:35PM +0800, Yicong Yang wrote:
>> The DMA operations of HiSilicon PTT device can only work properly with
>> identical mappings. So add a quirk for the device to force the domain
>> as passthrough.
>>
>> Signed-off-by: Yicong Yang <[email protected]>
>> ---
>> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 16 ++++++++++++++++
>> 1 file changed, 16 insertions(+)
>
> I still don't like this being part of the SMMU driver, but given that
> (a) Robin doesn't seem to agree with the objection and (b) you've been
> refreshing the patch series:
>
> Acked-by: Will Deacon <[email protected]>
>
> If you do respin, then:
>
>> diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
>> index 627a3ed5ee8f..5ec15ae2a9b1 100644
>> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
>> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
>> @@ -2839,6 +2839,21 @@ static int arm_smmu_dev_disable_feature(struct device *dev,
>> }
>> }
>
> It might be worth adding a brief comment here to explain what this device is
> and why it needs an identity mapping.
>
>> +#define IS_HISI_PTT_DEVICE(pdev) ((pdev)->vendor == PCI_VENDOR_ID_HUAWEI && \
>> + (pdev)->device == 0xa12e)
>
Will add a brief comment here in next version.
Thanks,
Yicong
On 10/05/2022 12:18, Yicong Yang wrote:
> On 2022/5/10 17:46, James Clark wrote:
>>
>>
>> On 07/04/2022 13:58, Yicong Yang wrote:
>>> HiSilicon PCIe tune and trace device(PTT) is a PCIe Root Complex integrated
>>> Endpoint(RCiEP) device, providing the capability to dynamically monitor and
>>> tune the PCIe traffic, and trace the TLP headers.
>>>
>>> Add the driver for the device to enable the trace function. Register PMU
>>> device of PTT trace, then users can use trace through perf command. The
>>> driver makes use of perf AUX trace and support following events to
>>> configure the trace:
>>>
>>> - filter: select Root port or Endpoint to trace
>>> - type: select the type of traced TLP headers
>>> - direction: select the direction of traced TLP headers
>>> - format: select the data format of the traced TLP headers
>>>
>>> This patch adds the driver part of PTT trace. The perf command support of
>>> PTT trace is added in the following patch.
>>>
>>> Signed-off-by: Yicong Yang <[email protected]>
>>> Reviewed-by: Jonathan Cameron <[email protected]>
>>> ---
>>> drivers/Makefile | 1 +
>>> drivers/hwtracing/Kconfig | 2 +
>>> drivers/hwtracing/ptt/Kconfig | 12 +
>>> drivers/hwtracing/ptt/Makefile | 2 +
>>> drivers/hwtracing/ptt/hisi_ptt.c | 874 +++++++++++++++++++++++++++++++
>>> drivers/hwtracing/ptt/hisi_ptt.h | 166 ++++++
>>> 6 files changed, 1057 insertions(+)
>>> create mode 100644 drivers/hwtracing/ptt/Kconfig
>>> create mode 100644 drivers/hwtracing/ptt/Makefile
>>> create mode 100644 drivers/hwtracing/ptt/hisi_ptt.c
>>> create mode 100644 drivers/hwtracing/ptt/hisi_ptt.h
>>>
>>> diff --git a/drivers/Makefile b/drivers/Makefile
>>> index 020780b6b4d2..662d50599467 100644
>>> --- a/drivers/Makefile
>>> +++ b/drivers/Makefile
>>> @@ -175,6 +175,7 @@ obj-$(CONFIG_USB4) += thunderbolt/
>>> obj-$(CONFIG_CORESIGHT) += hwtracing/coresight/
>>> obj-y += hwtracing/intel_th/
>>> obj-$(CONFIG_STM) += hwtracing/stm/
>>> +obj-$(CONFIG_HISI_PTT) += hwtracing/ptt/
>>> obj-$(CONFIG_ANDROID) += android/
>>> obj-$(CONFIG_NVMEM) += nvmem/
>>> obj-$(CONFIG_FPGA) += fpga/
>>> diff --git a/drivers/hwtracing/Kconfig b/drivers/hwtracing/Kconfig
>>> index 13085835a636..911ee977103c 100644
>>> --- a/drivers/hwtracing/Kconfig
>>> +++ b/drivers/hwtracing/Kconfig
>>> @@ -5,4 +5,6 @@ source "drivers/hwtracing/stm/Kconfig"
>>>
>>> source "drivers/hwtracing/intel_th/Kconfig"
>>>
>>> +source "drivers/hwtracing/ptt/Kconfig"
>>> +
>>> endmenu
>>> diff --git a/drivers/hwtracing/ptt/Kconfig b/drivers/hwtracing/ptt/Kconfig
>>> new file mode 100644
>>> index 000000000000..8902a6f27563
>>> --- /dev/null
>>> +++ b/drivers/hwtracing/ptt/Kconfig
>>> @@ -0,0 +1,12 @@
>>> +# SPDX-License-Identifier: GPL-2.0-only
>>> +config HISI_PTT
>>> + tristate "HiSilicon PCIe Tune and Trace Device"
>>> + depends on ARM64 || (COMPILE_TEST && 64BIT)
>>> + depends on PCI && HAS_DMA && HAS_IOMEM && PERF_EVENTS
>>> + help
>>> + HiSilicon PCIe Tune and Trace Device exists as a PCIe RCiEP
>>> + device, and it provides support for PCIe traffic tuning and
>>> + tracing TLP headers to the memory.
>>> +
>>> + This driver can also be built as a module. If so, the module
>>> + will be called hisi_ptt.
>>> diff --git a/drivers/hwtracing/ptt/Makefile b/drivers/hwtracing/ptt/Makefile
>>> new file mode 100644
>>> index 000000000000..908c09a98161
>>> --- /dev/null
>>> +++ b/drivers/hwtracing/ptt/Makefile
>>> @@ -0,0 +1,2 @@
>>> +# SPDX-License-Identifier: GPL-2.0
>>> +obj-$(CONFIG_HISI_PTT) += hisi_ptt.o
>>> diff --git a/drivers/hwtracing/ptt/hisi_ptt.c b/drivers/hwtracing/ptt/hisi_ptt.c
>>> new file mode 100644
>>> index 000000000000..242b41870380
>>> --- /dev/null
>>> +++ b/drivers/hwtracing/ptt/hisi_ptt.c
>>> @@ -0,0 +1,874 @@
>>> +// SPDX-License-Identifier: GPL-2.0
>>> +/*
>>> + * Driver for HiSilicon PCIe tune and trace device
>>> + *
>>> + * Copyright (c) 2022 HiSilicon Technologies Co., Ltd.
>>> + * Author: Yicong Yang <[email protected]>
>>> + */
>>> +
>>> +#include <linux/bitfield.h>
>>> +#include <linux/bitops.h>
>>> +#include <linux/delay.h>
>>> +#include <linux/dma-iommu.h>
>>> +#include <linux/dma-mapping.h>
>>> +#include <linux/interrupt.h>
>>> +#include <linux/io.h>
>>> +#include <linux/iommu.h>
>>> +#include <linux/iopoll.h>
>>> +#include <linux/module.h>
>>> +#include <linux/sysfs.h>
>>> +#include <linux/vmalloc.h>
>>> +
>>> +#include "hisi_ptt.h"
>>> +
>>> +static u16 hisi_ptt_get_filter_val(struct pci_dev *pdev)
>>> +{
>>> + if (pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT)
>>> + return BIT(HISI_PCIE_CORE_PORT_ID(PCI_SLOT(pdev->devfn)));
>>> +
>>> + return PCI_DEVID(pdev->bus->number, pdev->devfn);
>>> +}
>>> +
>>> +static bool hisi_ptt_wait_trace_hw_idle(struct hisi_ptt *hisi_ptt)
>>> +{
>>> + u32 val;
>>> +
>>> + return !readl_poll_timeout_atomic(hisi_ptt->iobase + HISI_PTT_TRACE_STS,
>>> + val, val & HISI_PTT_TRACE_IDLE,
>>> + HISI_PTT_WAIT_POLL_INTERVAL_US,
>>> + HISI_PTT_WAIT_TRACE_TIMEOUT_US);
>>> +}
>>> +
>>> +static bool hisi_ptt_wait_dma_reset_done(struct hisi_ptt *hisi_ptt)
>>> +{
>>> + u32 val;
>>> +
>>> + return !readl_poll_timeout_atomic(hisi_ptt->iobase + HISI_PTT_TRACE_WR_STS,
>>> + val, !val, HISI_PTT_RESET_POLL_INTERVAL_US,
>>> + HISI_PTT_RESET_TIMEOUT_US);
>>> +}
>>> +
>>> +static void hisi_ptt_free_trace_buf(struct hisi_ptt *hisi_ptt)
>>> +{
>>> + struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
>>> + struct device *dev = &hisi_ptt->pdev->dev;
>>> + int i;
>>> +
>>> + if (!ctrl->trace_buf)
>>> + return;
>>> +
>>> + for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; i++) {
>>> + if (ctrl->trace_buf[i].addr)
>>> + dmam_free_coherent(dev, HISI_PTT_TRACE_BUF_SIZE,
>>> + ctrl->trace_buf[i].addr,
>>> + ctrl->trace_buf[i].dma);
>>> + }
>>> +
>>> + devm_kfree(dev, ctrl->trace_buf);
>>> + ctrl->trace_buf = NULL;
>>> +}
>>> +
>>> +static int hisi_ptt_alloc_trace_buf(struct hisi_ptt *hisi_ptt)
>>> +{
>>> + struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
>>> + struct device *dev = &hisi_ptt->pdev->dev;
>>> + int i;
>>> +
>>> + hisi_ptt->trace_ctrl.buf_index = 0;
>>> +
>>> + /* If the trace buffer has already been allocated, zero it. */
>>> + if (ctrl->trace_buf) {
>>> + for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; i++)
>>> + memset(ctrl->trace_buf[i].addr, 0, HISI_PTT_TRACE_BUF_SIZE);
>>> + return 0;
>>> + }
>>> +
>>> + ctrl->trace_buf = devm_kcalloc(dev, HISI_PTT_TRACE_BUF_CNT,
>>> + sizeof(struct hisi_ptt_dma_buffer), GFP_KERNEL);
>>> + if (!ctrl->trace_buf)
>>> + return -ENOMEM;
>>> +
>>> + for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; ++i) {
>>> + ctrl->trace_buf[i].addr = dmam_alloc_coherent(dev, HISI_PTT_TRACE_BUF_SIZE,
>>> + &ctrl->trace_buf[i].dma,
>>> + GFP_KERNEL);
>>> + if (!ctrl->trace_buf[i].addr) {
>>> + hisi_ptt_free_trace_buf(hisi_ptt);
>>> + return -ENOMEM;
>>> + }
>>> + }
>>> +
>>> + return 0;
>>> +}
>>> +
>>> +static void hisi_ptt_trace_end(struct hisi_ptt *hisi_ptt)
>>> +{
>>> + writel(0, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
>>> + hisi_ptt->trace_ctrl.started = false;
>>> +}
>>> +
>>> +static int hisi_ptt_trace_start(struct hisi_ptt *hisi_ptt)
>>> +{
>>> + struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
>>> + u32 val;
>>> + int i;
>>> +
>>> + /* Check device idle before start trace */
>>> + if (!hisi_ptt_wait_trace_hw_idle(hisi_ptt)) {
>>> + pci_err(hisi_ptt->pdev, "Failed to start trace, the device is still busy\n");
>>> + return -EBUSY;
>>> + }
>>> +
>>> + ctrl->started = true;
>>> +
>>> + /* Reset the DMA before start tracing */
>>> + val = readl(hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
>>> + val |= HISI_PTT_TRACE_CTRL_RST;
>>> + writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
>>> +
>>> + hisi_ptt_wait_dma_reset_done(hisi_ptt);
>>> +
>>> + val = readl(hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
>>> + val &= ~HISI_PTT_TRACE_CTRL_RST;
>>> + writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
>>> +
>>> + /* Clear the interrupt status */
>>> + writel(HISI_PTT_TRACE_INT_STAT_MASK, hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
>>> + writel(0, hisi_ptt->iobase + HISI_PTT_TRACE_INT_MASK);
>>> +
>>> + /* Configure the trace DMA buffer */
>>> + for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; i++) {
>>> + writel(lower_32_bits(ctrl->trace_buf[i].dma),
>>> + hisi_ptt->iobase + HISI_PTT_TRACE_ADDR_BASE_LO_0 +
>>> + i * HISI_PTT_TRACE_ADDR_STRIDE);
>>> + writel(upper_32_bits(ctrl->trace_buf[i].dma),
>>> + hisi_ptt->iobase + HISI_PTT_TRACE_ADDR_BASE_HI_0 +
>>> + i * HISI_PTT_TRACE_ADDR_STRIDE);
>>> + }
>>> + writel(HISI_PTT_TRACE_BUF_SIZE, hisi_ptt->iobase + HISI_PTT_TRACE_ADDR_SIZE);
>>> +
>>> + /* Set the trace control register */
>>> + val = FIELD_PREP(HISI_PTT_TRACE_CTRL_TYPE_SEL, ctrl->type);
>>> + val |= FIELD_PREP(HISI_PTT_TRACE_CTRL_RXTX_SEL, ctrl->direction);
>>> + val |= FIELD_PREP(HISI_PTT_TRACE_CTRL_DATA_FORMAT, ctrl->format);
>>> + val |= FIELD_PREP(HISI_PTT_TRACE_CTRL_TARGET_SEL, hisi_ptt->trace_ctrl.filter);
>>> + if (!hisi_ptt->trace_ctrl.is_port)
>>> + val |= HISI_PTT_TRACE_CTRL_FILTER_MODE;
>>> +
>>> + /* Start the Trace */
>>> + val |= HISI_PTT_TRACE_CTRL_EN;
>>> + writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
>>> +
>>> + return 0;
>>> +}
>>> +
>>> +static int hisi_ptt_update_aux(struct hisi_ptt *hisi_ptt, int index, bool stop)
>>> +{
>>> + struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
>>> + struct perf_output_handle *handle = &ctrl->handle;
>>> + struct perf_event *event = handle->event;
>>> + struct hisi_ptt_pmu_buf *buf;
>>> + void *addr;
>>> +
>>> + buf = perf_get_aux(handle);
>>> + if (!buf || !handle->size)
>>> + return -EINVAL;
>>> +
>>> + addr = ctrl->trace_buf[ctrl->buf_index].addr;
>>> +
>>> + memcpy(buf->base + buf->pos, addr, HISI_PTT_TRACE_BUF_SIZE);
>>> + memset(addr, 0, HISI_PTT_TRACE_BUF_SIZE);
>>
>> Hi Kicong,
>>
>> I also have the same comment as Leo here, I don't think the memset is
>> required.
>>
>
> It's necessary in the current approach as we always commit HISI_PTT_TRACE_BUF_SIZE
> data but the buffer maybe partly filled (called when perf going to stopp, not by the
> interrupt). The buffer is cleared so the unfilled part of the buffer will have
> empty data (normal traced TLP headers won't be all 0), then the user can distinguish
> the valid part of the data.
>
> I'm trying to only copy the traced data rather than the whole buffer then the
> clear operation here will be unnecessary. The hardware provide a register indicating
> which offset of which buffer it's currently writing to and it canbe used here.
If only the traced data is copied rather than the full buffer, isn't that what
perf_aux_output_end() is for? Perf will only read up to the point where you
say the buffer is filled to, it won't go and read the zeros if you didn't tell
it to by emitting perf_aux_output_end() for more data than was written.
If you are having to write zeros to detect which bits of the buffer is filled
or not it sounds like those zero parts are making it into the perf file and are
wasting disk space and CPU cycles to copy them.
>
>>> + buf->pos += HISI_PTT_TRACE_BUF_SIZE;
>>> +
>>> + if (stop) {
>>> + perf_aux_output_end(handle, buf->pos);
>>> + } else if (buf->length - buf->pos < HISI_PTT_TRACE_BUF_SIZE) {
>>> + perf_aux_output_skip(handle, buf->length - buf->pos);
>>
>> perf_aux_output_skip() can also return an error so should probably also
>> be checked like perf_aux_output_begin()
>>
>
> ok it should be checked.
>
>> I'm also wondering why there is a skip for every output_end()? Is that
>> to avoid having two memcpy calls to handle the wrap around if the data
>> to be copied goes past the end of the aux buffer?
>>
>> For example if your buffers are 4MB each and the aux buffer that the
>> user picked isn't a multiple of 4 I can see you needing to write the
>> first part of the 4MB to the end of the aux buffer and then the last
>> part to the beginning which would be two memcpy() calls. And then a
>> skip wouldn't be required.
>>
>
> I intended to handle the case that AUX buffer is not a multiple of 4 MiB.
> When the resident AUX buffer size is less than 4MiB, we're not going to
> commit data to it and will apply a new AUX buffer instead. I think you're
> right that the perf_aux_output_skip() is unnecessary here. Thanks for
> catching this.
>
>> I looked at all the other uses of perf_output_end() and perf_output_skip()
>> in the kernel and didn't see a pattern like yours so it seems suspicous to
>> me. Maybe at least some comments around this section are needed.
>>
>
> Will add some comments of the handling here.
>
> Regards,
> Yicong
On 2022/5/10 20:54, James Clark wrote:
>
>
> On 10/05/2022 12:18, Yicong Yang wrote:
>> On 2022/5/10 17:46, James Clark wrote:
>>>
>>>
>>> On 07/04/2022 13:58, Yicong Yang wrote:
>>>> HiSilicon PCIe tune and trace device(PTT) is a PCIe Root Complex integrated
>>>> Endpoint(RCiEP) device, providing the capability to dynamically monitor and
>>>> tune the PCIe traffic, and trace the TLP headers.
>>>>
>>>> Add the driver for the device to enable the trace function. Register PMU
>>>> device of PTT trace, then users can use trace through perf command. The
>>>> driver makes use of perf AUX trace and support following events to
>>>> configure the trace:
>>>>
>>>> - filter: select Root port or Endpoint to trace
>>>> - type: select the type of traced TLP headers
>>>> - direction: select the direction of traced TLP headers
>>>> - format: select the data format of the traced TLP headers
>>>>
>>>> This patch adds the driver part of PTT trace. The perf command support of
>>>> PTT trace is added in the following patch.
>>>>
>>>> Signed-off-by: Yicong Yang <[email protected]>
>>>> Reviewed-by: Jonathan Cameron <[email protected]>
>>>> ---
>>>> drivers/Makefile | 1 +
>>>> drivers/hwtracing/Kconfig | 2 +
>>>> drivers/hwtracing/ptt/Kconfig | 12 +
>>>> drivers/hwtracing/ptt/Makefile | 2 +
>>>> drivers/hwtracing/ptt/hisi_ptt.c | 874 +++++++++++++++++++++++++++++++
>>>> drivers/hwtracing/ptt/hisi_ptt.h | 166 ++++++
>>>> 6 files changed, 1057 insertions(+)
>>>> create mode 100644 drivers/hwtracing/ptt/Kconfig
>>>> create mode 100644 drivers/hwtracing/ptt/Makefile
>>>> create mode 100644 drivers/hwtracing/ptt/hisi_ptt.c
>>>> create mode 100644 drivers/hwtracing/ptt/hisi_ptt.h
>>>>
>>>> diff --git a/drivers/Makefile b/drivers/Makefile
>>>> index 020780b6b4d2..662d50599467 100644
>>>> --- a/drivers/Makefile
>>>> +++ b/drivers/Makefile
>>>> @@ -175,6 +175,7 @@ obj-$(CONFIG_USB4) += thunderbolt/
>>>> obj-$(CONFIG_CORESIGHT) += hwtracing/coresight/
>>>> obj-y += hwtracing/intel_th/
>>>> obj-$(CONFIG_STM) += hwtracing/stm/
>>>> +obj-$(CONFIG_HISI_PTT) += hwtracing/ptt/
>>>> obj-$(CONFIG_ANDROID) += android/
>>>> obj-$(CONFIG_NVMEM) += nvmem/
>>>> obj-$(CONFIG_FPGA) += fpga/
>>>> diff --git a/drivers/hwtracing/Kconfig b/drivers/hwtracing/Kconfig
>>>> index 13085835a636..911ee977103c 100644
>>>> --- a/drivers/hwtracing/Kconfig
>>>> +++ b/drivers/hwtracing/Kconfig
>>>> @@ -5,4 +5,6 @@ source "drivers/hwtracing/stm/Kconfig"
>>>>
>>>> source "drivers/hwtracing/intel_th/Kconfig"
>>>>
>>>> +source "drivers/hwtracing/ptt/Kconfig"
>>>> +
>>>> endmenu
>>>> diff --git a/drivers/hwtracing/ptt/Kconfig b/drivers/hwtracing/ptt/Kconfig
>>>> new file mode 100644
>>>> index 000000000000..8902a6f27563
>>>> --- /dev/null
>>>> +++ b/drivers/hwtracing/ptt/Kconfig
>>>> @@ -0,0 +1,12 @@
>>>> +# SPDX-License-Identifier: GPL-2.0-only
>>>> +config HISI_PTT
>>>> + tristate "HiSilicon PCIe Tune and Trace Device"
>>>> + depends on ARM64 || (COMPILE_TEST && 64BIT)
>>>> + depends on PCI && HAS_DMA && HAS_IOMEM && PERF_EVENTS
>>>> + help
>>>> + HiSilicon PCIe Tune and Trace Device exists as a PCIe RCiEP
>>>> + device, and it provides support for PCIe traffic tuning and
>>>> + tracing TLP headers to the memory.
>>>> +
>>>> + This driver can also be built as a module. If so, the module
>>>> + will be called hisi_ptt.
>>>> diff --git a/drivers/hwtracing/ptt/Makefile b/drivers/hwtracing/ptt/Makefile
>>>> new file mode 100644
>>>> index 000000000000..908c09a98161
>>>> --- /dev/null
>>>> +++ b/drivers/hwtracing/ptt/Makefile
>>>> @@ -0,0 +1,2 @@
>>>> +# SPDX-License-Identifier: GPL-2.0
>>>> +obj-$(CONFIG_HISI_PTT) += hisi_ptt.o
>>>> diff --git a/drivers/hwtracing/ptt/hisi_ptt.c b/drivers/hwtracing/ptt/hisi_ptt.c
>>>> new file mode 100644
>>>> index 000000000000..242b41870380
>>>> --- /dev/null
>>>> +++ b/drivers/hwtracing/ptt/hisi_ptt.c
>>>> @@ -0,0 +1,874 @@
>>>> +// SPDX-License-Identifier: GPL-2.0
>>>> +/*
>>>> + * Driver for HiSilicon PCIe tune and trace device
>>>> + *
>>>> + * Copyright (c) 2022 HiSilicon Technologies Co., Ltd.
>>>> + * Author: Yicong Yang <[email protected]>
>>>> + */
>>>> +
>>>> +#include <linux/bitfield.h>
>>>> +#include <linux/bitops.h>
>>>> +#include <linux/delay.h>
>>>> +#include <linux/dma-iommu.h>
>>>> +#include <linux/dma-mapping.h>
>>>> +#include <linux/interrupt.h>
>>>> +#include <linux/io.h>
>>>> +#include <linux/iommu.h>
>>>> +#include <linux/iopoll.h>
>>>> +#include <linux/module.h>
>>>> +#include <linux/sysfs.h>
>>>> +#include <linux/vmalloc.h>
>>>> +
>>>> +#include "hisi_ptt.h"
>>>> +
>>>> +static u16 hisi_ptt_get_filter_val(struct pci_dev *pdev)
>>>> +{
>>>> + if (pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT)
>>>> + return BIT(HISI_PCIE_CORE_PORT_ID(PCI_SLOT(pdev->devfn)));
>>>> +
>>>> + return PCI_DEVID(pdev->bus->number, pdev->devfn);
>>>> +}
>>>> +
>>>> +static bool hisi_ptt_wait_trace_hw_idle(struct hisi_ptt *hisi_ptt)
>>>> +{
>>>> + u32 val;
>>>> +
>>>> + return !readl_poll_timeout_atomic(hisi_ptt->iobase + HISI_PTT_TRACE_STS,
>>>> + val, val & HISI_PTT_TRACE_IDLE,
>>>> + HISI_PTT_WAIT_POLL_INTERVAL_US,
>>>> + HISI_PTT_WAIT_TRACE_TIMEOUT_US);
>>>> +}
>>>> +
>>>> +static bool hisi_ptt_wait_dma_reset_done(struct hisi_ptt *hisi_ptt)
>>>> +{
>>>> + u32 val;
>>>> +
>>>> + return !readl_poll_timeout_atomic(hisi_ptt->iobase + HISI_PTT_TRACE_WR_STS,
>>>> + val, !val, HISI_PTT_RESET_POLL_INTERVAL_US,
>>>> + HISI_PTT_RESET_TIMEOUT_US);
>>>> +}
>>>> +
>>>> +static void hisi_ptt_free_trace_buf(struct hisi_ptt *hisi_ptt)
>>>> +{
>>>> + struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
>>>> + struct device *dev = &hisi_ptt->pdev->dev;
>>>> + int i;
>>>> +
>>>> + if (!ctrl->trace_buf)
>>>> + return;
>>>> +
>>>> + for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; i++) {
>>>> + if (ctrl->trace_buf[i].addr)
>>>> + dmam_free_coherent(dev, HISI_PTT_TRACE_BUF_SIZE,
>>>> + ctrl->trace_buf[i].addr,
>>>> + ctrl->trace_buf[i].dma);
>>>> + }
>>>> +
>>>> + devm_kfree(dev, ctrl->trace_buf);
>>>> + ctrl->trace_buf = NULL;
>>>> +}
>>>> +
>>>> +static int hisi_ptt_alloc_trace_buf(struct hisi_ptt *hisi_ptt)
>>>> +{
>>>> + struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
>>>> + struct device *dev = &hisi_ptt->pdev->dev;
>>>> + int i;
>>>> +
>>>> + hisi_ptt->trace_ctrl.buf_index = 0;
>>>> +
>>>> + /* If the trace buffer has already been allocated, zero it. */
>>>> + if (ctrl->trace_buf) {
>>>> + for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; i++)
>>>> + memset(ctrl->trace_buf[i].addr, 0, HISI_PTT_TRACE_BUF_SIZE);
>>>> + return 0;
>>>> + }
>>>> +
>>>> + ctrl->trace_buf = devm_kcalloc(dev, HISI_PTT_TRACE_BUF_CNT,
>>>> + sizeof(struct hisi_ptt_dma_buffer), GFP_KERNEL);
>>>> + if (!ctrl->trace_buf)
>>>> + return -ENOMEM;
>>>> +
>>>> + for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; ++i) {
>>>> + ctrl->trace_buf[i].addr = dmam_alloc_coherent(dev, HISI_PTT_TRACE_BUF_SIZE,
>>>> + &ctrl->trace_buf[i].dma,
>>>> + GFP_KERNEL);
>>>> + if (!ctrl->trace_buf[i].addr) {
>>>> + hisi_ptt_free_trace_buf(hisi_ptt);
>>>> + return -ENOMEM;
>>>> + }
>>>> + }
>>>> +
>>>> + return 0;
>>>> +}
>>>> +
>>>> +static void hisi_ptt_trace_end(struct hisi_ptt *hisi_ptt)
>>>> +{
>>>> + writel(0, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
>>>> + hisi_ptt->trace_ctrl.started = false;
>>>> +}
>>>> +
>>>> +static int hisi_ptt_trace_start(struct hisi_ptt *hisi_ptt)
>>>> +{
>>>> + struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
>>>> + u32 val;
>>>> + int i;
>>>> +
>>>> + /* Check device idle before start trace */
>>>> + if (!hisi_ptt_wait_trace_hw_idle(hisi_ptt)) {
>>>> + pci_err(hisi_ptt->pdev, "Failed to start trace, the device is still busy\n");
>>>> + return -EBUSY;
>>>> + }
>>>> +
>>>> + ctrl->started = true;
>>>> +
>>>> + /* Reset the DMA before start tracing */
>>>> + val = readl(hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
>>>> + val |= HISI_PTT_TRACE_CTRL_RST;
>>>> + writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
>>>> +
>>>> + hisi_ptt_wait_dma_reset_done(hisi_ptt);
>>>> +
>>>> + val = readl(hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
>>>> + val &= ~HISI_PTT_TRACE_CTRL_RST;
>>>> + writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
>>>> +
>>>> + /* Clear the interrupt status */
>>>> + writel(HISI_PTT_TRACE_INT_STAT_MASK, hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
>>>> + writel(0, hisi_ptt->iobase + HISI_PTT_TRACE_INT_MASK);
>>>> +
>>>> + /* Configure the trace DMA buffer */
>>>> + for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; i++) {
>>>> + writel(lower_32_bits(ctrl->trace_buf[i].dma),
>>>> + hisi_ptt->iobase + HISI_PTT_TRACE_ADDR_BASE_LO_0 +
>>>> + i * HISI_PTT_TRACE_ADDR_STRIDE);
>>>> + writel(upper_32_bits(ctrl->trace_buf[i].dma),
>>>> + hisi_ptt->iobase + HISI_PTT_TRACE_ADDR_BASE_HI_0 +
>>>> + i * HISI_PTT_TRACE_ADDR_STRIDE);
>>>> + }
>>>> + writel(HISI_PTT_TRACE_BUF_SIZE, hisi_ptt->iobase + HISI_PTT_TRACE_ADDR_SIZE);
>>>> +
>>>> + /* Set the trace control register */
>>>> + val = FIELD_PREP(HISI_PTT_TRACE_CTRL_TYPE_SEL, ctrl->type);
>>>> + val |= FIELD_PREP(HISI_PTT_TRACE_CTRL_RXTX_SEL, ctrl->direction);
>>>> + val |= FIELD_PREP(HISI_PTT_TRACE_CTRL_DATA_FORMAT, ctrl->format);
>>>> + val |= FIELD_PREP(HISI_PTT_TRACE_CTRL_TARGET_SEL, hisi_ptt->trace_ctrl.filter);
>>>> + if (!hisi_ptt->trace_ctrl.is_port)
>>>> + val |= HISI_PTT_TRACE_CTRL_FILTER_MODE;
>>>> +
>>>> + /* Start the Trace */
>>>> + val |= HISI_PTT_TRACE_CTRL_EN;
>>>> + writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
>>>> +
>>>> + return 0;
>>>> +}
>>>> +
>>>> +static int hisi_ptt_update_aux(struct hisi_ptt *hisi_ptt, int index, bool stop)
>>>> +{
>>>> + struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
>>>> + struct perf_output_handle *handle = &ctrl->handle;
>>>> + struct perf_event *event = handle->event;
>>>> + struct hisi_ptt_pmu_buf *buf;
>>>> + void *addr;
>>>> +
>>>> + buf = perf_get_aux(handle);
>>>> + if (!buf || !handle->size)
>>>> + return -EINVAL;
>>>> +
>>>> + addr = ctrl->trace_buf[ctrl->buf_index].addr;
>>>> +
>>>> + memcpy(buf->base + buf->pos, addr, HISI_PTT_TRACE_BUF_SIZE);
>>>> + memset(addr, 0, HISI_PTT_TRACE_BUF_SIZE);
>>>
>>> Hi Kicong,
>>>
>>> I also have the same comment as Leo here, I don't think the memset is
>>> required.
>>>
>>
>> It's necessary in the current approach as we always commit HISI_PTT_TRACE_BUF_SIZE
>> data but the buffer maybe partly filled (called when perf going to stopp, not by the
>> interrupt). The buffer is cleared so the unfilled part of the buffer will have
>> empty data (normal traced TLP headers won't be all 0), then the user can distinguish
>> the valid part of the data.
>>
>> I'm trying to only copy the traced data rather than the whole buffer then the
>> clear operation here will be unnecessary. The hardware provide a register indicating
>> which offset of which buffer it's currently writing to and it canbe used here.
>
> If only the traced data is copied rather than the full buffer, isn't that what
> perf_aux_output_end() is for? Perf will only read up to the point where you
> say the buffer is filled to, it won't go and read the zeros if you didn't tell
> it to by emitting perf_aux_output_end() for more data than was written.
>
> If you are having to write zeros to detect which bits of the buffer is filled
> or not it sounds like those zero parts are making it into the perf file and are
> wasting disk space and CPU cycles to copy them.
>
For the approach in this version, you're right that we'll waste CPU cycles to copy
them. But this will only happens when the perf session is going stop, as in the
updating from interrupts we'll always have data of full buffer size (interrupt only
comes when the buffer is filled fully). The data will be like (perf report -D):
[...]
. 00000004: 00 00 00 00 Prefix
. 00000008: 01 80 00 60 Header DW0
. 0000000c: 0f 1e 00 01 Header DW1
. 00000010: c6 00 00 00 Header DW2
. 00000014: 40 00 01 60 Header DW3
. 0000001c: c5 94 d1 00 Time
. 0000005c: 14 00 00 00 Time
. 00000064: 00 00 00 00 Prefix
. 00000068: 00 00 00 00 Header DW0
. 0000006c: 00 00 00 00 Header DW1
. 00000070: 00 00 00 00 Header DW2
. 0000005c: 00 00 00 00 Time
[...zeroed data]
I'll change to only copy the valid data like below in next version. Then we won't
waste disk space and cpu time to copy it.
static int hisi_ptt_update_aux(struct hisi_ptt *hisi_ptt, int index, bool stop)
{
struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
struct perf_output_handle *handle = &ctrl->handle;
struct perf_event *event = handle->event;
struct hisi_ptt_pmu_buf *buf;
void *addr;
size_t sz;
buf = perf_get_aux(handle);
if (!buf || !handle->size)
return -EINVAL;
addr = ctrl->trace_buf[ctrl->buf_index].addr;
if (stop) {
u32 reg;
reg = readl(hisi_ptt->iobase + HISI_PTT_TRACE_WR_STS);
sz = FIELD_GET(HISI_PTT_TRACE_WR_STS_WRITE, reg);
} else {
sz = HISI_PTT_TRACE_BUF_SIZE;
}
memcpy(buf->base + buf->pos, addr, sz);
buf->pos += sz;
/*
* Just commit the traced data if we're going to stop. Otherwise if the
* resident AUX buffer cannot contain data of next trace buffer, apply
* a new one.
*/
if (stop) {
perf_aux_output_end(handle, buf->pos);
} else if (buf->length - buf->pos < HISI_PTT_TRACE_BUF_SIZE) {
perf_aux_output_end(handle, buf->pos);
buf = perf_aux_output_begin(handle, event);
if (!buf)
return -EINVAL;
buf->pos = handle->head % buf->length;
if (buf->length - buf->pos < HISI_PTT_TRACE_BUF_SIZE) {
perf_aux_output_end(handle, 0);
return -EINVAL;
}
}
return 0;
}
>>
>>>> + buf->pos += HISI_PTT_TRACE_BUF_SIZE;
>>>> +
>>>> + if (stop) {
>>>> + perf_aux_output_end(handle, buf->pos);
>>>> + } else if (buf->length - buf->pos < HISI_PTT_TRACE_BUF_SIZE) {
>>>> + perf_aux_output_skip(handle, buf->length - buf->pos);
>>>
>>> perf_aux_output_skip() can also return an error so should probably also
>>> be checked like perf_aux_output_begin()
>>>
>>
>> ok it should be checked.
>>
>>> I'm also wondering why there is a skip for every output_end()? Is that
>>> to avoid having two memcpy calls to handle the wrap around if the data
>>> to be copied goes past the end of the aux buffer?
>>>
>>> For example if your buffers are 4MB each and the aux buffer that the
>>> user picked isn't a multiple of 4 I can see you needing to write the
>>> first part of the 4MB to the end of the aux buffer and then the last
>>> part to the beginning which would be two memcpy() calls. And then a
>>> skip wouldn't be required.
>>>
>>
>> I intended to handle the case that AUX buffer is not a multiple of 4 MiB.
>> When the resident AUX buffer size is less than 4MiB, we're not going to
>> commit data to it and will apply a new AUX buffer instead. I think you're
>> right that the perf_aux_output_skip() is unnecessary here. Thanks for
>> catching this.
>>
>>> I looked at all the other uses of perf_output_end() and perf_output_skip()
>>> in the kernel and didn't see a pattern like yours so it seems suspicous to
>>> me. Maybe at least some comments around this section are needed.
>>>
>>
>> Will add some comments of the handling here.
>>
>> Regards,
>> Yicong
> .
>
On 07/04/2022 13:58, Yicong Yang wrote:
> The DMA operations of HiSilicon PTT device can only work properly with
> identical mappings. So add a quirk for the device to force the domain
I'm not sure if you meant to write "identity mappings".
> as passthrough.
>
> Signed-off-by: Yicong Yang <[email protected]>
FWIW,
Reviewed-by: John Garry <[email protected]>
> ---
> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 16 ++++++++++++++++
> 1 file changed, 16 insertions(+)
>
> diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> index 627a3ed5ee8f..5ec15ae2a9b1 100644
> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> @@ -2839,6 +2839,21 @@ static int arm_smmu_dev_disable_feature(struct device *dev,
> }
> }
>
> +#define IS_HISI_PTT_DEVICE(pdev) ((pdev)->vendor == PCI_VENDOR_ID_HUAWEI && \
> + (pdev)->device == 0xa12e)
> +
> +static int arm_smmu_def_domain_type(struct device *dev)
> +{
> + if (dev_is_pci(dev)) {
> + struct pci_dev *pdev = to_pci_dev(dev);
> +
> + if (IS_HISI_PTT_DEVICE(pdev))
> + return IOMMU_DOMAIN_IDENTITY;
> + }
> +
> + return 0;
> +}
> +
> static struct iommu_ops arm_smmu_ops = {
> .capable = arm_smmu_capable,
> .domain_alloc = arm_smmu_domain_alloc,
> @@ -2856,6 +2871,7 @@ static struct iommu_ops arm_smmu_ops = {
> .sva_unbind = arm_smmu_sva_unbind,
> .sva_get_pasid = arm_smmu_sva_get_pasid,
> .page_response = arm_smmu_page_response,
> + .def_domain_type = arm_smmu_def_domain_type,
> .pgsize_bitmap = -1UL, /* Restricted during device attach */
> .owner = THIS_MODULE,
> .default_domain_ops = &(const struct iommu_domain_ops) {