2015-12-22 23:44:01

by David Daney

[permalink] [raw]
Subject: [PATCH v2 0/2] pci: Add host controller driver for Cavium ThunderX PCIe

From: David Daney <[email protected]>

Some Cavium ThunderX processors require quirky access methods for the
config space of the PCIe bridge.

There are two patches:

1) Refactor code in pci-host-generic so that it can more easily be
used by other drivers. This splits the driver for CAM and ECAM
access methods to a separate file from the common host driver code.

2) Add the ThunderX PCIe driver, which leverages the code in
pci-host-generic


Changes from v1: Split CAM and ECAM code from common driver code as
suggested by Arnd Bergmann. Fix spelling errors in
pcie-thunder-pem.txt

David Daney (2):
PCI: generic: Refactor code to enable reuse by other drivers.
pci, pcie-thunder-pem: Add PCIe host driver for ThunderX processors.

.../devicetree/bindings/pci/pcie-thunder-pem.txt | 43 ++++
drivers/pci/host/Kconfig | 11 +
drivers/pci/host/Makefile | 2 +
drivers/pci/host/pci-host-common.c | 194 ++++++++++++++
drivers/pci/host/pci-host-common.h | 56 ++++
drivers/pci/host/pci-host-generic.c | 190 +-------------
drivers/pci/host/pcie-thunder-pem.c | 283 +++++++++++++++++++++
7 files changed, 593 insertions(+), 186 deletions(-)
create mode 100644 Documentation/devicetree/bindings/pci/pcie-thunder-pem.txt
create mode 100644 drivers/pci/host/pci-host-common.c
create mode 100644 drivers/pci/host/pci-host-common.h
create mode 100644 drivers/pci/host/pcie-thunder-pem.c

--
1.8.3.1


2015-12-22 23:44:13

by David Daney

[permalink] [raw]
Subject: [PATCH v2 1/2] PCI: generic: Refactor code to enable reuse by other drivers.

From: David Daney <[email protected]>

No change in functionality.

Move structure definitions into a separate header file. Move common
code to new file with Kconfig machinery to build it. Split probe
function in to two parts:

- a small driver specific probe function (gen_pci_probe)

- a common probe that can be used by other drivers
(pci_host_common_probe)

Signed-off-by: David Daney <[email protected]>
---
drivers/pci/host/Kconfig | 4 +
drivers/pci/host/Makefile | 1 +
drivers/pci/host/pci-host-common.c | 194 ++++++++++++++++++++++++++++++++++++
drivers/pci/host/pci-host-common.h | 56 +++++++++++
drivers/pci/host/pci-host-generic.c | 190 +----------------------------------
5 files changed, 259 insertions(+), 186 deletions(-)
create mode 100644 drivers/pci/host/pci-host-common.c
create mode 100644 drivers/pci/host/pci-host-common.h

diff --git a/drivers/pci/host/Kconfig b/drivers/pci/host/Kconfig
index f131ba9..f171459 100644
--- a/drivers/pci/host/Kconfig
+++ b/drivers/pci/host/Kconfig
@@ -53,9 +53,13 @@ config PCI_RCAR_GEN2_PCIE
help
Say Y here if you want PCIe controller support on R-Car Gen2 SoCs.

+config PCI_HOST_COMMON
+ bool
+
config PCI_HOST_GENERIC
bool "Generic PCI host controller"
depends on (ARM || ARM64) && OF
+ select PCI_HOST_COMMON
help
Say Y here if you want to support a simple generic PCI host
controller, such as the one emulated by kvmtool.
diff --git a/drivers/pci/host/Makefile b/drivers/pci/host/Makefile
index 9d4d3c6..ba2c51f 100644
--- a/drivers/pci/host/Makefile
+++ b/drivers/pci/host/Makefile
@@ -6,6 +6,7 @@ obj-$(CONFIG_PCI_MVEBU) += pci-mvebu.o
obj-$(CONFIG_PCI_TEGRA) += pci-tegra.o
obj-$(CONFIG_PCI_RCAR_GEN2) += pci-rcar-gen2.o
obj-$(CONFIG_PCI_RCAR_GEN2_PCIE) += pcie-rcar.o
+obj-$(CONFIG_PCI_HOST_COMMON) += pci-host-common.o
obj-$(CONFIG_PCI_HOST_GENERIC) += pci-host-generic.o
obj-$(CONFIG_PCIE_SPEAR13XX) += pcie-spear13xx.o
obj-$(CONFIG_PCI_KEYSTONE) += pci-keystone-dw.o pci-keystone.o
diff --git a/drivers/pci/host/pci-host-common.c b/drivers/pci/host/pci-host-common.c
new file mode 100644
index 0000000..e9f850f
--- /dev/null
+++ b/drivers/pci/host/pci-host-common.c
@@ -0,0 +1,194 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Copyright (C) 2014 ARM Limited
+ *
+ * Author: Will Deacon <[email protected]>
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_pci.h>
+#include <linux/platform_device.h>
+
+#include "pci-host-common.h"
+
+static void gen_pci_release_of_pci_ranges(struct gen_pci *pci)
+{
+ pci_free_resource_list(&pci->resources);
+}
+
+static int gen_pci_parse_request_of_pci_ranges(struct gen_pci *pci)
+{
+ int err, res_valid = 0;
+ struct device *dev = pci->host.dev.parent;
+ struct device_node *np = dev->of_node;
+ resource_size_t iobase;
+ struct resource_entry *win;
+
+ err = of_pci_get_host_bridge_resources(np, 0, 0xff, &pci->resources,
+ &iobase);
+ if (err)
+ return err;
+
+ resource_list_for_each_entry(win, &pci->resources) {
+ struct resource *parent, *res = win->res;
+
+ switch (resource_type(res)) {
+ case IORESOURCE_IO:
+ parent = &ioport_resource;
+ err = pci_remap_iospace(res, iobase);
+ if (err) {
+ dev_warn(dev, "error %d: failed to map resource %pR\n",
+ err, res);
+ continue;
+ }
+ break;
+ case IORESOURCE_MEM:
+ parent = &iomem_resource;
+ res_valid |= !(res->flags & IORESOURCE_PREFETCH);
+ break;
+ case IORESOURCE_BUS:
+ pci->cfg.bus_range = res;
+ default:
+ continue;
+ }
+
+ err = devm_request_resource(dev, parent, res);
+ if (err)
+ goto out_release_res;
+ }
+
+ if (!res_valid) {
+ dev_err(dev, "non-prefetchable memory resource required\n");
+ err = -EINVAL;
+ goto out_release_res;
+ }
+
+ return 0;
+
+out_release_res:
+ gen_pci_release_of_pci_ranges(pci);
+ return err;
+}
+
+static int gen_pci_parse_map_cfg_windows(struct gen_pci *pci)
+{
+ int err;
+ u8 bus_max;
+ resource_size_t busn;
+ struct resource *bus_range;
+ struct device *dev = pci->host.dev.parent;
+ struct device_node *np = dev->of_node;
+ u32 sz = 1 << pci->cfg.ops->bus_shift;
+
+ err = of_address_to_resource(np, 0, &pci->cfg.res);
+ if (err) {
+ dev_err(dev, "missing \"reg\" property\n");
+ return err;
+ }
+
+ /* Limit the bus-range to fit within reg */
+ bus_max = pci->cfg.bus_range->start +
+ (resource_size(&pci->cfg.res) >> pci->cfg.ops->bus_shift) - 1;
+ pci->cfg.bus_range->end = min_t(resource_size_t,
+ pci->cfg.bus_range->end, bus_max);
+
+ pci->cfg.win = devm_kcalloc(dev, resource_size(pci->cfg.bus_range),
+ sizeof(*pci->cfg.win), GFP_KERNEL);
+ if (!pci->cfg.win)
+ return -ENOMEM;
+
+ /* Map our Configuration Space windows */
+ if (!devm_request_mem_region(dev, pci->cfg.res.start,
+ resource_size(&pci->cfg.res),
+ "Configuration Space"))
+ return -ENOMEM;
+
+ bus_range = pci->cfg.bus_range;
+ for (busn = bus_range->start; busn <= bus_range->end; ++busn) {
+ u32 idx = busn - bus_range->start;
+
+ pci->cfg.win[idx] = devm_ioremap(dev,
+ pci->cfg.res.start + idx * sz,
+ sz);
+ if (!pci->cfg.win[idx])
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+int pci_host_common_probe(struct platform_device *pdev,
+ struct gen_pci *pci)
+{
+ int err;
+ const char *type;
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ struct pci_bus *bus, *child;
+
+ type = of_get_property(np, "device_type", NULL);
+ if (!type || strcmp(type, "pci")) {
+ dev_err(dev, "invalid \"device_type\" %s\n", type);
+ return -EINVAL;
+ }
+
+ of_pci_check_probe_only();
+
+ pci->host.dev.parent = dev;
+ INIT_LIST_HEAD(&pci->host.windows);
+ INIT_LIST_HEAD(&pci->resources);
+
+ /* Parse our PCI ranges and request their resources */
+ err = gen_pci_parse_request_of_pci_ranges(pci);
+ if (err)
+ return err;
+
+ /* Parse and map our Configuration Space windows */
+ err = gen_pci_parse_map_cfg_windows(pci);
+ if (err) {
+ gen_pci_release_of_pci_ranges(pci);
+ return err;
+ }
+
+ /* Do not reassign resources if probe only */
+ if (!pci_has_flag(PCI_PROBE_ONLY))
+ pci_add_flags(PCI_REASSIGN_ALL_RSRC | PCI_REASSIGN_ALL_BUS);
+
+
+ bus = pci_scan_root_bus(dev, pci->cfg.bus_range->start,
+ &pci->cfg.ops->ops, pci, &pci->resources);
+ if (!bus) {
+ dev_err(dev, "Scanning rootbus failed");
+ return -ENODEV;
+ }
+
+ pci_fixup_irqs(pci_common_swizzle, of_irq_parse_and_map_pci);
+
+ if (!pci_has_flag(PCI_PROBE_ONLY)) {
+ pci_bus_size_bridges(bus);
+ pci_bus_assign_resources(bus);
+
+ list_for_each_entry(child, &bus->children, node)
+ pcie_bus_configure_settings(child);
+ }
+
+ pci_bus_add_devices(bus);
+ return 0;
+}
+
+MODULE_DESCRIPTION("Generic PCI host driver common code");
+MODULE_AUTHOR("Will Deacon <[email protected]>");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/pci/host/pci-host-common.h b/drivers/pci/host/pci-host-common.h
new file mode 100644
index 0000000..9423808
--- /dev/null
+++ b/drivers/pci/host/pci-host-common.h
@@ -0,0 +1,56 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Copyright (C) 2014 ARM Limited
+ *
+ * Author: Will Deacon <[email protected]>
+ */
+
+#ifndef _PCI_HOST_COMMON_H
+#define _PCI_HOST_COMMON_H
+
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+
+struct gen_pci_cfg_bus_ops {
+ u32 bus_shift;
+ struct pci_ops ops;
+};
+
+struct gen_pci_cfg_windows {
+ struct resource res;
+ struct resource *bus_range;
+ void __iomem **win;
+
+ struct gen_pci_cfg_bus_ops *ops;
+};
+
+/*
+ * ARM pcibios functions expect the ARM struct pci_sys_data as the PCI
+ * sysdata. Add pci_sys_data as the first element in struct gen_pci so
+ * that when we use a gen_pci pointer as sysdata, it is also a pointer to
+ * a struct pci_sys_data.
+ */
+struct gen_pci {
+#ifdef CONFIG_ARM
+ struct pci_sys_data sys;
+#endif
+ struct pci_host_bridge host;
+ struct gen_pci_cfg_windows cfg;
+ struct list_head resources;
+};
+
+int pci_host_common_probe(struct platform_device *pdev,
+ struct gen_pci *pci);
+
+#endif /* _PCI_HOST_COMMON_H */
diff --git a/drivers/pci/host/pci-host-generic.c b/drivers/pci/host/pci-host-generic.c
index 5434c90..e8aa78f 100644
--- a/drivers/pci/host/pci-host-generic.c
+++ b/drivers/pci/host/pci-host-generic.c
@@ -25,33 +25,7 @@
#include <linux/of_pci.h>
#include <linux/platform_device.h>

-struct gen_pci_cfg_bus_ops {
- u32 bus_shift;
- struct pci_ops ops;
-};
-
-struct gen_pci_cfg_windows {
- struct resource res;
- struct resource *bus_range;
- void __iomem **win;
-
- struct gen_pci_cfg_bus_ops *ops;
-};
-
-/*
- * ARM pcibios functions expect the ARM struct pci_sys_data as the PCI
- * sysdata. Add pci_sys_data as the first element in struct gen_pci so
- * that when we use a gen_pci pointer as sysdata, it is also a pointer to
- * a struct pci_sys_data.
- */
-struct gen_pci {
-#ifdef CONFIG_ARM
- struct pci_sys_data sys;
-#endif
- struct pci_host_bridge host;
- struct gen_pci_cfg_windows cfg;
- struct list_head resources;
-};
+#include "pci-host-common.h"

static void __iomem *gen_pci_map_cfg_bus_cam(struct pci_bus *bus,
unsigned int devfn,
@@ -102,175 +76,19 @@ static const struct of_device_id gen_pci_of_match[] = {
};
MODULE_DEVICE_TABLE(of, gen_pci_of_match);

-static void gen_pci_release_of_pci_ranges(struct gen_pci *pci)
-{
- pci_free_resource_list(&pci->resources);
-}
-
-static int gen_pci_parse_request_of_pci_ranges(struct gen_pci *pci)
-{
- int err, res_valid = 0;
- struct device *dev = pci->host.dev.parent;
- struct device_node *np = dev->of_node;
- resource_size_t iobase;
- struct resource_entry *win;
-
- err = of_pci_get_host_bridge_resources(np, 0, 0xff, &pci->resources,
- &iobase);
- if (err)
- return err;
-
- resource_list_for_each_entry(win, &pci->resources) {
- struct resource *parent, *res = win->res;
-
- switch (resource_type(res)) {
- case IORESOURCE_IO:
- parent = &ioport_resource;
- err = pci_remap_iospace(res, iobase);
- if (err) {
- dev_warn(dev, "error %d: failed to map resource %pR\n",
- err, res);
- continue;
- }
- break;
- case IORESOURCE_MEM:
- parent = &iomem_resource;
- res_valid |= !(res->flags & IORESOURCE_PREFETCH);
- break;
- case IORESOURCE_BUS:
- pci->cfg.bus_range = res;
- default:
- continue;
- }
-
- err = devm_request_resource(dev, parent, res);
- if (err)
- goto out_release_res;
- }
-
- if (!res_valid) {
- dev_err(dev, "non-prefetchable memory resource required\n");
- err = -EINVAL;
- goto out_release_res;
- }
-
- return 0;
-
-out_release_res:
- gen_pci_release_of_pci_ranges(pci);
- return err;
-}
-
-static int gen_pci_parse_map_cfg_windows(struct gen_pci *pci)
-{
- int err;
- u8 bus_max;
- resource_size_t busn;
- struct resource *bus_range;
- struct device *dev = pci->host.dev.parent;
- struct device_node *np = dev->of_node;
- u32 sz = 1 << pci->cfg.ops->bus_shift;
-
- err = of_address_to_resource(np, 0, &pci->cfg.res);
- if (err) {
- dev_err(dev, "missing \"reg\" property\n");
- return err;
- }
-
- /* Limit the bus-range to fit within reg */
- bus_max = pci->cfg.bus_range->start +
- (resource_size(&pci->cfg.res) >> pci->cfg.ops->bus_shift) - 1;
- pci->cfg.bus_range->end = min_t(resource_size_t,
- pci->cfg.bus_range->end, bus_max);
-
- pci->cfg.win = devm_kcalloc(dev, resource_size(pci->cfg.bus_range),
- sizeof(*pci->cfg.win), GFP_KERNEL);
- if (!pci->cfg.win)
- return -ENOMEM;
-
- /* Map our Configuration Space windows */
- if (!devm_request_mem_region(dev, pci->cfg.res.start,
- resource_size(&pci->cfg.res),
- "Configuration Space"))
- return -ENOMEM;
-
- bus_range = pci->cfg.bus_range;
- for (busn = bus_range->start; busn <= bus_range->end; ++busn) {
- u32 idx = busn - bus_range->start;
-
- pci->cfg.win[idx] = devm_ioremap(dev,
- pci->cfg.res.start + idx * sz,
- sz);
- if (!pci->cfg.win[idx])
- return -ENOMEM;
- }
-
- return 0;
-}
-
static int gen_pci_probe(struct platform_device *pdev)
{
- int err;
- const char *type;
- const struct of_device_id *of_id;
struct device *dev = &pdev->dev;
- struct device_node *np = dev->of_node;
+ const struct of_device_id *of_id;
struct gen_pci *pci = devm_kzalloc(dev, sizeof(*pci), GFP_KERNEL);
- struct pci_bus *bus, *child;

if (!pci)
return -ENOMEM;

- type = of_get_property(np, "device_type", NULL);
- if (!type || strcmp(type, "pci")) {
- dev_err(dev, "invalid \"device_type\" %s\n", type);
- return -EINVAL;
- }
-
- of_pci_check_probe_only();
-
- of_id = of_match_node(gen_pci_of_match, np);
+ of_id = of_match_node(gen_pci_of_match, dev->of_node);
pci->cfg.ops = (struct gen_pci_cfg_bus_ops *)of_id->data;
- pci->host.dev.parent = dev;
- INIT_LIST_HEAD(&pci->host.windows);
- INIT_LIST_HEAD(&pci->resources);
-
- /* Parse our PCI ranges and request their resources */
- err = gen_pci_parse_request_of_pci_ranges(pci);
- if (err)
- return err;
-
- /* Parse and map our Configuration Space windows */
- err = gen_pci_parse_map_cfg_windows(pci);
- if (err) {
- gen_pci_release_of_pci_ranges(pci);
- return err;
- }
-
- /* Do not reassign resources if probe only */
- if (!pci_has_flag(PCI_PROBE_ONLY))
- pci_add_flags(PCI_REASSIGN_ALL_RSRC | PCI_REASSIGN_ALL_BUS);
-
-
- bus = pci_scan_root_bus(dev, pci->cfg.bus_range->start,
- &pci->cfg.ops->ops, pci, &pci->resources);
- if (!bus) {
- dev_err(dev, "Scanning rootbus failed");
- return -ENODEV;
- }
-
- pci_fixup_irqs(pci_common_swizzle, of_irq_parse_and_map_pci);
-
- if (!pci_has_flag(PCI_PROBE_ONLY)) {
- pci_bus_size_bridges(bus);
- pci_bus_assign_resources(bus);
-
- list_for_each_entry(child, &bus->children, node)
- pcie_bus_configure_settings(child);
- }

- pci_bus_add_devices(bus);
- return 0;
+ return pci_host_common_probe(pdev, pci);
}

static struct platform_driver gen_pci_driver = {
--
1.8.3.1

2015-12-22 23:44:45

by David Daney

[permalink] [raw]
Subject: [PATCH v2 2/2] pci, pcie-thunder-pem: Add PCIe host driver for ThunderX processors.

From: David Daney <[email protected]>

Some Cavium ThunderX processors require quirky access methods for the
config space of the PCIe bridge. Add a driver to provide these config
space accessor functions. The pci-host-common code is used to
configure the PCI machinery.

Signed-off-by: David Daney <[email protected]>
---
.../devicetree/bindings/pci/pcie-thunder-pem.txt | 43 ++++
drivers/pci/host/Kconfig | 7 +
drivers/pci/host/Makefile | 1 +
drivers/pci/host/pcie-thunder-pem.c | 283 +++++++++++++++++++++
4 files changed, 334 insertions(+)
create mode 100644 Documentation/devicetree/bindings/pci/pcie-thunder-pem.txt
create mode 100644 drivers/pci/host/pcie-thunder-pem.c

diff --git a/Documentation/devicetree/bindings/pci/pcie-thunder-pem.txt b/Documentation/devicetree/bindings/pci/pcie-thunder-pem.txt
new file mode 100644
index 0000000..52f56b3
--- /dev/null
+++ b/Documentation/devicetree/bindings/pci/pcie-thunder-pem.txt
@@ -0,0 +1,43 @@
+* ThunderX PEM PCIe host controller
+
+Firmware-initialized PCIe host controller found on some Cavium
+ThunderX processors.
+
+The properties and their meanings are identical to those described in
+host-generic-pci.txt except as listed below.
+
+Properties of the host controller node that differ from
+host-generic-pci.txt:
+
+- compatible : Must be "cavium,pci-host-thunder-pem"
+
+- reg : Two entries: First the configuration space for down
+ stream devices base address and size, as accessed
+ from the parent bus. Second, the register bank of
+ the PEM device PCIe bridge.
+
+Example:
+
+ pem2 {
+ compatible = "cavium,pci-host-thunder-pem";
+ device_type = "pci";
+ msi-parent = <&its>;
+ msi-map = <0 &its 0x10000 0x10000>;
+ bus-range = <0x8f 0xc7>;
+ #size-cells = <2>;
+ #address-cells = <3>;
+
+ reg = <0x8880 0x8f000000 0x0 0x39000000>, /* Configuration space */
+ <0x87e0 0xc2000000 0x0 0x00010000>; /* PEM space */
+ ranges = <0x01000000 0x00 0x00020000 0x88b0 0x00020000 0x00 0x00010000>, /* I/O */
+ <0x03000000 0x00 0x10000000 0x8890 0x10000000 0x0f 0xf0000000>, /* mem64 */
+ <0x43000000 0x10 0x00000000 0x88a0 0x00000000 0x10 0x00000000>, /* mem64-pref */
+ <0x03000000 0x87e0 0xc2f00000 0x87e0 0xc2000000 0x00 0x00100000>; /* mem64 PEM BAR4 */
+
+ #interrupt-cells = <1>;
+ interrupt-map-mask = <0 0 0 7>;
+ interrupt-map = <0 0 0 1 &gic0 0 0 0 24 4>, /* INTA */
+ <0 0 0 2 &gic0 0 0 0 25 4>, /* INTB */
+ <0 0 0 3 &gic0 0 0 0 26 4>, /* INTC */
+ <0 0 0 4 &gic0 0 0 0 27 4>; /* INTD */
+ };
diff --git a/drivers/pci/host/Kconfig b/drivers/pci/host/Kconfig
index f171459..6885667 100644
--- a/drivers/pci/host/Kconfig
+++ b/drivers/pci/host/Kconfig
@@ -176,4 +176,11 @@ config PCI_HISI
help
Say Y here if you want PCIe controller support on HiSilicon HIP05 SoC

+config PCIE_HOST_THUNDER_PEM
+ bool "Cavium Thunder PCIe controller to off-chip devices"
+ depends on OF && ARM64
+ select PCI_HOST_COMMON
+ help
+ Say Y here if you want PCIe support for CN88XX Cavium Thunder SoCs.
+
endmenu
diff --git a/drivers/pci/host/Makefile b/drivers/pci/host/Makefile
index ba2c51f..e3f3c78 100644
--- a/drivers/pci/host/Makefile
+++ b/drivers/pci/host/Makefile
@@ -21,3 +21,4 @@ obj-$(CONFIG_PCIE_IPROC_BCMA) += pcie-iproc-bcma.o
obj-$(CONFIG_PCIE_ALTERA) += pcie-altera.o
obj-$(CONFIG_PCIE_ALTERA_MSI) += pcie-altera-msi.o
obj-$(CONFIG_PCI_HISI) += pcie-hisi.o
+obj-$(CONFIG_PCIE_HOST_THUNDER_PEM) += pcie-thunder-pem.o
diff --git a/drivers/pci/host/pcie-thunder-pem.c b/drivers/pci/host/pcie-thunder-pem.c
new file mode 100644
index 0000000..cdf2df4
--- /dev/null
+++ b/drivers/pci/host/pcie-thunder-pem.c
@@ -0,0 +1,283 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Copyright (C) 2015 Cavium, Inc.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_pci.h>
+#include <linux/platform_device.h>
+
+#include "pci-host-common.h"
+
+#define PEM_CFG_WR 0x28
+#define PEM_CFG_RD 0x30
+
+struct thunder_pem_pci {
+ struct gen_pci gen_pci;
+ u32 ea_entry[3];
+ void __iomem *pem_reg_base;
+};
+
+static int thunder_pem_config_read(struct pci_bus *bus, unsigned int devfn,
+ int where, int size, u32 *val)
+{
+ int r;
+ struct thunder_pem_pci *pem_pci;
+ struct gen_pci *pci = bus->sysdata;
+
+ pem_pci = container_of(pci, struct thunder_pem_pci, gen_pci);
+
+ /*
+ * The first device on the bus in the PEM PCIe bridge.
+ * Special case its config access.
+ */
+ if (bus->number == pci->cfg.bus_range->start) {
+ u64 read_val;
+
+ if (devfn != 0 || where >= 2048) {
+ *val = ~0;
+ return PCIBIOS_DEVICE_NOT_FOUND;
+ }
+
+ /*
+ * 32-bit accesses only. Write the address to the low
+ * order bits of PEM_CFG_RD, then trigger the read by
+ * reading back. The config data lands in the upper
+ * 32-bits of PEM_CFG_RD.
+ */
+ read_val = where & ~3ull;
+ writeq(read_val, pem_pci->pem_reg_base + PEM_CFG_RD);
+ read_val = readq(pem_pci->pem_reg_base + PEM_CFG_RD);
+ read_val >>= 32;
+
+ /*
+ * The config space contains some garbage, fix it up.
+ * Also synthesize an EA capability for the BAR used
+ * by MSI-X.
+ */
+ switch (where & ~3u) {
+ case 0x40:
+ read_val &= 0xffff00ff;
+ read_val |= 0x00007000; /* Skip MSI CAP */
+ break;
+ case 0x70: /* Express Cap */
+ /* PME interrupt on vector 2*/
+ read_val |= (2u << 25);
+ break;
+ case 0xb0: /* MSI-X Cap */
+ /* TableSize=4, Next Cap is EA */
+ read_val &= 0xc00000ff;
+ read_val |= 0x0003bc00;
+ break;
+ case 0xb4:
+ /* Table offset=0, BIR=0 */
+ read_val = 0x00000000;
+ break;
+ case 0xb8:
+ /* BPA offset=0xf0000, BIR=0 */
+ read_val = 0x000f0000;
+ break;
+ case 0xbc:
+ /* EA, 1 entry, no next Cap */
+ read_val = 0x00010014;
+ break;
+ case 0xc0:
+ /* DW2 for type-1 */
+ read_val = 0x00000000;
+ break;
+ case 0xc4:
+ /* Entry BEI=0, PP=0x00, SP=0xff, ES=3 */
+ read_val = 0x80ff0003;
+ break;
+ case 0xc8:
+ read_val = pem_pci->ea_entry[0];
+ break;
+ case 0xcc:
+ read_val = pem_pci->ea_entry[1];
+ break;
+ case 0xd0:
+ read_val = pem_pci->ea_entry[2];
+ break;
+ default:
+ break;
+ }
+ read_val >>= (8 * (where & 3));
+ switch (size) {
+ case 1:
+ read_val &= 0xff;
+ break;
+ case 2:
+ read_val &= 0xffff;
+ break;
+ default:
+ break;
+ }
+ *val = read_val;
+ return PCIBIOS_SUCCESSFUL;
+ }
+ if (bus->number < pci->cfg.bus_range->start ||
+ bus->number > pci->cfg.bus_range->end)
+ return PCIBIOS_DEVICE_NOT_FOUND;
+
+ r = pci_generic_config_read(bus, devfn, where, size, val);
+ return r;
+}
+
+static int thunder_pem_config_write(struct pci_bus *bus, unsigned int devfn,
+ int where, int size, u32 val)
+{
+ struct gen_pci *pci = bus->sysdata;
+ struct thunder_pem_pci *pem_pci;
+
+ pem_pci = container_of(pci, struct thunder_pem_pci, gen_pci);
+
+ /*
+ * The first device on the bus in the PEM PCIe bridge.
+ * Special case its config access.
+ */
+ if (bus->number == pci->cfg.bus_range->start) {
+ u64 write_val, read_val;
+
+ if (devfn != 0 || where >= 2048)
+ return PCIBIOS_DEVICE_NOT_FOUND;
+
+ /*
+ * 32-bit accesses only. If the write is for a size
+ * smaller than 32-bits, we must first read the 32-bit
+ * value and merge in the desired bits and then write
+ * the whole 32-bits back out.
+ */
+ switch (size) {
+ case 1:
+ read_val = where & ~3ull;
+ writeq(read_val, pem_pci->pem_reg_base + PEM_CFG_RD);
+ read_val = readq(pem_pci->pem_reg_base + PEM_CFG_RD);
+ read_val >>= 32;
+ read_val &= ~(0xff << (8 * (where & 3)));
+ val = (val & 0xff) << (8 * (where & 3));
+ val |= (u32)read_val;
+ break;
+ case 2:
+ read_val = where & ~3ull;
+ writeq(read_val, pem_pci->pem_reg_base + PEM_CFG_RD);
+ read_val = readq(pem_pci->pem_reg_base + PEM_CFG_RD);
+ read_val >>= 32;
+ read_val &= ~(0xffff << (8 * (where & 3)));
+ val = (val & 0xffff) << (8 * (where & 3));
+ val |= (u32)read_val;
+ break;
+ default:
+ break;
+
+ }
+ /*
+ * Low order bits are the config address, the high
+ * order 32 bits are the data to be written.
+ */
+ write_val = where & ~3ull;
+ write_val |= (((u64)val) << 32);
+ writeq(write_val, pem_pci->pem_reg_base + PEM_CFG_WR);
+ return PCIBIOS_SUCCESSFUL;
+ }
+ if (bus->number < pci->cfg.bus_range->start ||
+ bus->number > pci->cfg.bus_range->end)
+ return PCIBIOS_DEVICE_NOT_FOUND;
+ return pci_generic_config_write(bus, devfn, where, size, val);
+}
+
+static void __iomem *map_cfg_bus_thunder_pem(struct pci_bus *bus,
+ unsigned int devfn,
+ int where)
+{
+ struct gen_pci *pci = bus->sysdata;
+ resource_size_t idx = bus->number - pci->cfg.bus_range->start;
+
+ return pci->cfg.win[idx] + ((devfn << 16) | where);
+}
+
+static struct gen_pci_cfg_bus_ops thunder_pem_bus_ops = {
+ .bus_shift = 24,
+ .ops = {
+ .map_bus = map_cfg_bus_thunder_pem,
+ .read = thunder_pem_config_read,
+ .write = thunder_pem_config_write,
+ }
+};
+
+static const struct of_device_id thunder_pem_of_match[] = {
+ { .compatible = "cavium,pci-host-thunder-pem",
+ .data = &thunder_pem_bus_ops },
+
+ { },
+};
+MODULE_DEVICE_TABLE(of, thunder_pem_of_match);
+
+static int thunder_pem_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ const struct of_device_id *of_id;
+ resource_size_t bar4_start;
+ struct resource *res_pem;
+ struct thunder_pem_pci *pem_pci;
+
+ pem_pci = devm_kzalloc(dev, sizeof(*pem_pci), GFP_KERNEL);
+ if (!pem_pci)
+ return -ENOMEM;
+
+ of_id = of_match_node(thunder_pem_of_match, dev->of_node);
+ pem_pci->gen_pci.cfg.ops = (struct gen_pci_cfg_bus_ops *)of_id->data;
+
+ /*
+ * The second register range is the PEM bridge to the PCIe
+ * bus. It has a different config access method than those
+ * devices behind the bridge.
+ */
+ res_pem = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+ if (!res_pem) {
+ dev_err(dev, "missing \"reg[1]\"property\n");
+ return -EINVAL;
+ }
+
+ pem_pci->pem_reg_base = devm_ioremap(dev, res_pem->start, 0x10000);
+ if (!pem_pci->pem_reg_base)
+ return -ENOMEM;
+
+ /*
+ * The MSI-X BAR for the PEM and AER interrupts is located at
+ * a fixed offset from the PEM register base. Generate a
+ * fragment of the synthesized Enhanced Allocation capability
+ * structure here for the BAR.
+ */
+ bar4_start = res_pem->start + 0xf00000;
+ pem_pci->ea_entry[0] = (u32)bar4_start | 2;
+ pem_pci->ea_entry[1] = (u32)(res_pem->end - bar4_start) & ~3u;
+ pem_pci->ea_entry[2] = (u32)(bar4_start >> 32);
+
+ return pci_host_common_probe(pdev, &pem_pci->gen_pci);
+}
+
+static struct platform_driver thunder_pem_driver = {
+ .driver = {
+ .name = "pcie-thunder-pem",
+ .of_match_table = thunder_pem_of_match,
+ },
+ .probe = thunder_pem_probe,
+};
+module_platform_driver(thunder_pem_driver);
+
+MODULE_DESCRIPTION("Thunder PEM PCIe host driver");
+MODULE_LICENSE("GPL v2");
--
1.8.3.1

2015-12-29 20:37:25

by Rob Herring

[permalink] [raw]
Subject: Re: [PATCH v2 2/2] pci, pcie-thunder-pem: Add PCIe host driver for ThunderX processors.

On Tue, Dec 22, 2015 at 03:43:52PM -0800, David Daney wrote:
> From: David Daney <[email protected]>
>
> Some Cavium ThunderX processors require quirky access methods for the
> config space of the PCIe bridge. Add a driver to provide these config
> space accessor functions. The pci-host-common code is used to
> configure the PCI machinery.

Same comments again...

> Signed-off-by: David Daney <[email protected]>
> ---
> .../devicetree/bindings/pci/pcie-thunder-pem.txt | 43 ++++
> drivers/pci/host/Kconfig | 7 +
> drivers/pci/host/Makefile | 1 +
> drivers/pci/host/pcie-thunder-pem.c | 283 +++++++++++++++++++++
> 4 files changed, 334 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/pci/pcie-thunder-pem.txt
> create mode 100644 drivers/pci/host/pcie-thunder-pem.c
>
> diff --git a/Documentation/devicetree/bindings/pci/pcie-thunder-pem.txt b/Documentation/devicetree/bindings/pci/pcie-thunder-pem.txt
> new file mode 100644
> index 0000000..52f56b3
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/pci/pcie-thunder-pem.txt
> @@ -0,0 +1,43 @@
> +* ThunderX PEM PCIe host controller
> +
> +Firmware-initialized PCIe host controller found on some Cavium
> +ThunderX processors.
> +
> +The properties and their meanings are identical to those described in
> +host-generic-pci.txt except as listed below.
> +
> +Properties of the host controller node that differ from
> +host-generic-pci.txt:
> +
> +- compatible : Must be "cavium,pci-host-thunder-pem"

pcie rather than pci?

> +
> +- reg : Two entries: First the configuration space for down
> + stream devices base address and size, as accessed
> + from the parent bus. Second, the register bank of
> + the PEM device PCIe bridge.
> +
> +Example:
> +
> + pem2 {

pcie-controller@... instead of pem2.

> + compatible = "cavium,pci-host-thunder-pem";
> + device_type = "pci";
> + msi-parent = <&its>;
> + msi-map = <0 &its 0x10000 0x10000>;
> + bus-range = <0x8f 0xc7>;
> + #size-cells = <2>;
> + #address-cells = <3>;
> +
> + reg = <0x8880 0x8f000000 0x0 0x39000000>, /* Configuration space */
> + <0x87e0 0xc2000000 0x0 0x00010000>; /* PEM space */
> + ranges = <0x01000000 0x00 0x00020000 0x88b0 0x00020000 0x00 0x00010000>, /* I/O */
> + <0x03000000 0x00 0x10000000 0x8890 0x10000000 0x0f 0xf0000000>, /* mem64 */
> + <0x43000000 0x10 0x00000000 0x88a0 0x00000000 0x10 0x00000000>, /* mem64-pref */
> + <0x03000000 0x87e0 0xc2f00000 0x87e0 0xc2000000 0x00 0x00100000>; /* mem64 PEM BAR4 */
> +
> + #interrupt-cells = <1>;
> + interrupt-map-mask = <0 0 0 7>;
> + interrupt-map = <0 0 0 1 &gic0 0 0 0 24 4>, /* INTA */
> + <0 0 0 2 &gic0 0 0 0 25 4>, /* INTB */
> + <0 0 0 3 &gic0 0 0 0 26 4>, /* INTC */
> + <0 0 0 4 &gic0 0 0 0 27 4>; /* INTD */
> + };