2016-12-14 22:11:05

by Agustin Vega-Frias

[permalink] [raw]
Subject: [PATCH V9 0/3] irqchip: qcom: Add IRQ combiner driver

Add support for IRQ combiners in the Top-level Control and Status
Registers (TCSR) hardware block in Qualcomm Technologies chips.

The first patch prevents the ACPI core from attempting to map IRQ resources
with a valid ResourceSource as GSIs.

The first patch adds support for ResourceSource/IRQ domain mapping and
fixes IRQ probe deferral by allowing platform_device IRQ resources to be
re-initialized from the corresponding ACPI IRQ resource.

Both changes described above are conditional on the ACPI_GENERIC_GSI config.

The third patch takes advantage of the new capabilities to implement
the driver for the IRQ combiners.

Tested on top of v4.9.

Changes V8 -> V9:
* Do not attempt the mapping for non-GSI IRQs during bus scan.
* Make some public APIs private to drivers/acpi/irq.c since they are no
longer used on other modules.

Changes V7 -> V8:
* Reorder patches to allow all new code to be under drivers/acpi/irq.c.
* Change acpi_irq_get implementation to be more similar to of_irq_get
to improve maintainability.

Agustin Vega-Frias (3):
ACPI: Generic GSI: Do not attempt to map non-GSI IRQs during bus scan
ACPI: Add support for ResourceSource/IRQ domain mapping
irqchip: qcom: Add IRQ combiner driver

drivers/acpi/Makefile | 2 +-
drivers/acpi/gsi.c | 98 -----------
drivers/acpi/irq.c | 280 +++++++++++++++++++++++++++++++
drivers/acpi/resource.c | 17 +-
drivers/base/platform.c | 9 +-
drivers/irqchip/Kconfig | 9 +
drivers/irqchip/Makefile | 1 +
drivers/irqchip/qcom-irq-combiner.c | 322 ++++++++++++++++++++++++++++++++++++
include/linux/acpi.h | 10 ++
9 files changed, 647 insertions(+), 101 deletions(-)
delete mode 100644 drivers/acpi/gsi.c
create mode 100644 drivers/acpi/irq.c
create mode 100644 drivers/irqchip/qcom-irq-combiner.c

--
Qualcomm Datacenter Technologies, Inc. on behalf of the Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.


2016-12-14 22:11:07

by Agustin Vega-Frias

[permalink] [raw]
Subject: [PATCH V9 1/3] ACPI: Generic GSI: Do not attempt to map non-GSI IRQs during bus scan

ACPI extended IRQ resources may contain a Resource Source field to specify
an alternate interrupt controller, attempting to map them as GSIs is
incorrect, so just disable the platform resource.

Since this field is currently ignored, we make this change conditional
on CONFIG_ACPI_GENERIC_GSI to keep the current behavior on x86 platforms,
in case some existing ACPI tables are using this incorrectly.

Signed-off-by: Agustin Vega-Frias <[email protected]>
---
drivers/acpi/resource.c | 17 ++++++++++++++++-
1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/drivers/acpi/resource.c b/drivers/acpi/resource.c
index 56241eb..76ca4e9 100644
--- a/drivers/acpi/resource.c
+++ b/drivers/acpi/resource.c
@@ -43,6 +43,18 @@ static inline bool acpi_iospace_resource_valid(struct resource *res)
acpi_iospace_resource_valid(struct resource *res) { return true; }
#endif

+#ifdef CONFIG_ACPI_GENERIC_GSI
+static inline bool is_gsi(struct acpi_resource_extended_irq *ext_irq)
+{
+ return ext_irq->resource_source.string_length == 0;
+}
+#else
+static inline bool is_gsi(struct acpi_resource_extended_irq *ext_irq)
+{
+ return true;
+}
+#endif
+
static bool acpi_dev_resource_len_valid(u64 start, u64 end, u64 len, bool io)
{
u64 reslen = end - start + 1;
@@ -470,9 +482,12 @@ bool acpi_dev_resource_interrupt(struct acpi_resource *ares, int index,
acpi_dev_irqresource_disabled(res, 0);
return false;
}
- acpi_dev_get_irqresource(res, ext_irq->interrupts[index],
+ if (is_gsi(ext_irq))
+ acpi_dev_get_irqresource(res, ext_irq->interrupts[index],
ext_irq->triggering, ext_irq->polarity,
ext_irq->sharable, false);
+ else
+ acpi_dev_irqresource_disabled(res, 0);
break;
default:
res->flags = 0;
--
Qualcomm Datacenter Technologies, Inc. on behalf of the Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.

2016-12-14 22:11:12

by Agustin Vega-Frias

[permalink] [raw]
Subject: [PATCH V9 2/3] ACPI: Add support for ResourceSource/IRQ domain mapping

ACPI extended IRQ resources may contain a ResourceSource to specify
an alternate interrupt controller. Introduce acpi_irq_get and use it
to implement ResourceSource/IRQ domain mapping.

The new API is similar to of_irq_get and allows re-initialization
of a platform resource from the ACPI extended IRQ resource, and
provides proper behavior for probe deferral when the domain is not
yet present when called.

Signed-off-by: Agustin Vega-Frias <[email protected]>
---
drivers/acpi/Makefile | 2 +-
drivers/acpi/{gsi.c => irq.c} | 182 ++++++++++++++++++++++++++++++++++++++++++
drivers/base/platform.c | 9 ++-
include/linux/acpi.h | 10 +++
4 files changed, 201 insertions(+), 2 deletions(-)
rename drivers/acpi/{gsi.c => irq.c} (32%)

diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
index 9ed0878..a391bbc 100644
--- a/drivers/acpi/Makefile
+++ b/drivers/acpi/Makefile
@@ -55,7 +55,7 @@ acpi-$(CONFIG_DEBUG_FS) += debugfs.o
acpi-$(CONFIG_ACPI_NUMA) += numa.o
acpi-$(CONFIG_ACPI_PROCFS_POWER) += cm_sbs.o
acpi-y += acpi_lpat.o
-acpi-$(CONFIG_ACPI_GENERIC_GSI) += gsi.o
+acpi-$(CONFIG_ACPI_GENERIC_GSI) += irq.o
acpi-$(CONFIG_ACPI_WATCHDOG) += acpi_watchdog.o

# These are (potentially) separate modules
diff --git a/drivers/acpi/gsi.c b/drivers/acpi/irq.c
similarity index 32%
rename from drivers/acpi/gsi.c
rename to drivers/acpi/irq.c
index ee9e0f2..133d3f8 100644
--- a/drivers/acpi/gsi.c
+++ b/drivers/acpi/irq.c
@@ -85,6 +85,188 @@ void acpi_unregister_gsi(u32 gsi)
EXPORT_SYMBOL_GPL(acpi_unregister_gsi);

/**
+ * acpi_get_irq_source_fwhandle() - Retrieve the fwhandle of the given
+ * acpi_resource_source which is used
+ * as an IRQ domain id
+ * @source: acpi_resource_source to use for the lookup
+ *
+ * Returns: The appropriate IRQ fwhandle domain id
+ * NULL on failure
+ */
+static struct fwnode_handle *
+acpi_get_irq_source_fwhandle(const struct acpi_resource_source *source)
+{
+ struct fwnode_handle *result;
+ struct acpi_device *device;
+ acpi_handle handle;
+ acpi_status status;
+
+ if (!source->string_length)
+ return acpi_gsi_domain_id;
+
+ status = acpi_get_handle(NULL, source->string_ptr, &handle);
+ if (ACPI_FAILURE(status)) {
+ pr_warn("Could not find handle for %s\n", source->string_ptr);
+ return NULL;
+ }
+
+ device = acpi_bus_get_acpi_device(handle);
+ if (!device) {
+ pr_warn("Could not get device for %s\n", source->string_ptr);
+ return NULL;
+ }
+
+ result = &device->fwnode;
+ acpi_bus_put_acpi_device(device);
+
+ return result;
+}
+
+/**
+ * Context for the resource walk used to lookup IRQ resources.
+ */
+struct acpi_irq_parse_one_ctx {
+ int rc;
+ unsigned int index;
+ unsigned long *res_flags;
+ struct irq_fwspec *fwspec;
+};
+
+/**
+ * acpi_irq_parse_one_match - Handle a matching IRQ resource
+ */
+static inline void acpi_irq_parse_one_match(struct fwnode_handle *fwnode,
+ u32 hwirq, u8 triggering,
+ u8 polarity, u8 shareable,
+ struct acpi_irq_parse_one_ctx *ctx)
+{
+ ctx->rc = 0;
+ *ctx->res_flags = acpi_dev_irq_flags(triggering, polarity, shareable);
+ ctx->fwspec->fwnode = fwnode;
+ ctx->fwspec->param[0] = hwirq;
+ ctx->fwspec->param[1] = acpi_dev_get_irq_type(triggering, polarity);
+ ctx->fwspec->param_count = 2;
+}
+
+/**
+ * acpi_irq_parse_one_cb - Handle the given resource
+ * @ares: resource to handle
+ * @context: context for the walk, contains the lookup index and references
+ * to the flags and fwspec where the result is returned
+ *
+ * This is called by acpi_walk_resources passing each resource returned by
+ * the _CRS method. We only inspect IRQ resources. Since IRQ resources
+ * might contain multiple interrupts we check if the index is within this
+ * one's interrupt array, otherwise we subtract the current resource IRQ
+ * count from the lookup index to prepare for the next resource.
+ * Once a match is found we call acpi_irq_parse_one_match to populate
+ * the result and end the walk by returning AE_CTRL_TERMINATE.
+ *
+ * Return AE_OK if the walk should continue, AE_CTRL_TERMINATE if a matching
+ * IRQ resource was found.
+ */
+static acpi_status acpi_irq_parse_one_cb(struct acpi_resource *ares,
+ void *context)
+{
+ struct acpi_irq_parse_one_ctx *ctx = context;
+ struct acpi_resource_irq *irq;
+ struct acpi_resource_extended_irq *eirq;
+ struct fwnode_handle *fwnode;
+
+ switch (ares->type) {
+ case ACPI_RESOURCE_TYPE_IRQ:
+ irq = &ares->data.irq;
+ if (ctx->index >= irq->interrupt_count) {
+ ctx->index -= irq->interrupt_count;
+ return AE_OK;
+ }
+ fwnode = acpi_gsi_domain_id;
+ acpi_irq_parse_one_match(fwnode, irq->interrupts[ctx->index],
+ irq->triggering, irq->polarity,
+ irq->sharable, ctx);
+ return AE_CTRL_TERMINATE;
+ case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
+ eirq = &ares->data.extended_irq;
+ if (ctx->index >= eirq->interrupt_count) {
+ ctx->index -= eirq->interrupt_count;
+ return AE_OK;
+ }
+ fwnode = acpi_get_irq_source_fwhandle(&eirq->resource_source);
+ acpi_irq_parse_one_match(fwnode, eirq->interrupts[ctx->index],
+ eirq->triggering, eirq->polarity,
+ eirq->sharable, ctx);
+ return AE_CTRL_TERMINATE;
+ }
+
+ return AE_OK;
+}
+
+/**
+ * acpi_irq_parse_one - Resolve an interrupt for a device
+ * @handle: the device whose interrupt is to be resolved
+ * @index: index of the interrupt to resolve
+ * @fwspec: structure irq_fwspec filled by this function
+ * @flags: resource flags filled by this function
+ *
+ * This function resolves an interrupt for a device by walking its CRS resources
+ * to find the appropriate ACPI IRQ resource and populating the given structure
+ * which can be used to retrieve a Linux IRQ number.
+ *
+ * Returns the result stored in ctx.rc by the callback, or -EINVAL if the given
+ * index is out of range.
+ */
+static int acpi_irq_parse_one(acpi_handle handle, unsigned int index,
+ struct irq_fwspec *fwspec, unsigned long *flags)
+{
+ struct acpi_irq_parse_one_ctx ctx = { -EINVAL, index, flags, fwspec };
+ acpi_status status;
+
+ status = acpi_walk_resources(handle, METHOD_NAME__CRS,
+ acpi_irq_parse_one_cb, &ctx);
+ if (ACPI_FAILURE(status))
+ return -EINVAL;
+ return ctx.rc;
+}
+
+/**
+ * acpi_irq_get - Look for the ACPI IRQ resource with the given index and
+ * use it to initialize the given Linux IRQ resource.
+ * @handle ACPI device handle
+ * @index ACPI IRQ resource index to lookup
+ * @res Linux IRQ resource to initialize
+ *
+ * Return: 0 on success
+ * -EINVAL if an error occurs
+ * -EPROBE_DEFER if the IRQ lookup/conversion failed
+ */
+int acpi_irq_get(acpi_handle handle, unsigned int index, struct resource *res)
+{
+ int rc;
+ struct irq_fwspec fwspec;
+ struct irq_domain *domain;
+ unsigned long flags;
+
+ rc = acpi_irq_parse_one(handle, index, &fwspec, &flags);
+ if (rc)
+ return rc;
+
+ domain = irq_find_matching_fwnode(fwspec.fwnode, DOMAIN_BUS_ANY);
+ if (!domain)
+ return -EPROBE_DEFER;
+
+ rc = irq_create_fwspec_mapping(&fwspec);
+ if (rc <= 0)
+ return -EINVAL;
+
+ res->start = rc;
+ res->end = rc;
+ res->flags = flags;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(acpi_irq_get);
+
+/**
* acpi_set_irq_model - Setup the GSI irqdomain information
* @model: the value assigned to acpi_irq_model
* @fwnode: the irq_domain identifier for mapping and looking up
diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index c4af003..61423d2 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -102,6 +102,14 @@ int platform_get_irq(struct platform_device *dev, unsigned int num)
}

r = platform_get_resource(dev, IORESOURCE_IRQ, num);
+ if (r && r->flags & IORESOURCE_DISABLED && ACPI_COMPANION(&dev->dev)) {
+ int ret;
+
+ ret = acpi_irq_get(ACPI_HANDLE(&dev->dev), num, r);
+ if (ret)
+ return ret;
+ }
+
/*
* The resources may pass trigger flags to the irqs that need
* to be set up. It so happens that the trigger flags for
@@ -1450,4 +1458,3 @@ void __init early_platform_cleanup(void)
memset(&pd->dev.devres_head, 0, sizeof(pd->dev.devres_head));
}
}
-
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 61a3d90..2284fc6 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -1123,4 +1123,14 @@ static inline void acpi_table_upgrade(void) { }
static inline int parse_spcr(bool earlycon) { return 0; }
#endif

+#ifdef CONFIG_ACPI_GENERIC_GSI
+int acpi_irq_get(acpi_handle handle, unsigned int index, struct resource *res);
+#else
+static inline int acpi_irq_get(acpi_handle handle, unsigned int index,
+ struct resource *res)
+{
+ return -EINVAL;
+}
+#endif
+
#endif /*_LINUX_ACPI_H*/
--
Qualcomm Datacenter Technologies, Inc. on behalf of the Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.

2016-12-14 22:11:24

by Agustin Vega-Frias

[permalink] [raw]
Subject: [PATCH V9 3/3] irqchip: qcom: Add IRQ combiner driver

Driver for interrupt combiners in the Top-level Control and Status
Registers (TCSR) hardware block in Qualcomm Technologies chips.

An interrupt combiner in this block combines a set of interrupts by
OR'ing the individual interrupt signals into a summary interrupt
signal routed to a parent interrupt controller, and provides read-
only, 32-bit registers to query the status of individual interrupts.
The status bit for IRQ n is bit (n % 32) within register (n / 32)
of the given combiner. Thus, each combiner can be described as a set
of register offsets and the number of IRQs managed.

Signed-off-by: Agustin Vega-Frias <[email protected]>
---
drivers/irqchip/Kconfig | 9 +
drivers/irqchip/Makefile | 1 +
drivers/irqchip/qcom-irq-combiner.c | 322 ++++++++++++++++++++++++++++++++++++
3 files changed, 332 insertions(+)
create mode 100644 drivers/irqchip/qcom-irq-combiner.c

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index bc0af33..3e3430c 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -279,3 +279,12 @@ config EZNPS_GIC
config STM32_EXTI
bool
select IRQ_DOMAIN
+
+config QCOM_IRQ_COMBINER
+ bool "QCOM IRQ combiner support"
+ depends on ARCH_QCOM && ACPI
+ select IRQ_DOMAIN
+ select IRQ_DOMAIN_HIERARCHY
+ help
+ Say yes here to add support for the IRQ combiner devices embedded
+ in Qualcomm Technologies chips.
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index e4dbfc8..1818a0b 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -74,3 +74,4 @@ obj-$(CONFIG_LS_SCFG_MSI) += irq-ls-scfg-msi.o
obj-$(CONFIG_EZNPS_GIC) += irq-eznps.o
obj-$(CONFIG_ARCH_ASPEED) += irq-aspeed-vic.o
obj-$(CONFIG_STM32_EXTI) += irq-stm32-exti.o
+obj-$(CONFIG_QCOM_IRQ_COMBINER) += qcom-irq-combiner.o
diff --git a/drivers/irqchip/qcom-irq-combiner.c b/drivers/irqchip/qcom-irq-combiner.c
new file mode 100644
index 0000000..0055e08
--- /dev/null
+++ b/drivers/irqchip/qcom-irq-combiner.c
@@ -0,0 +1,322 @@
+/* Copyright (c) 2015-2016, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only 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.
+ */
+
+/*
+ * Driver for interrupt combiners in the Top-level Control and Status
+ * Registers (TCSR) hardware block in Qualcomm Technologies chips.
+ * An interrupt combiner in this block combines a set of interrupts by
+ * OR'ing the individual interrupt signals into a summary interrupt
+ * signal routed to a parent interrupt controller, and provides read-
+ * only, 32-bit registers to query the status of individual interrupts.
+ * The status bit for IRQ n is bit (n % 32) within register (n / 32)
+ * of the given combiner. Thus, each combiner can be described as a set
+ * of register offsets and the number of IRQs managed.
+ */
+
+#include <linux/acpi.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/irqdomain.h>
+#include <linux/platform_device.h>
+
+#define REG_SIZE 32
+
+struct combiner_reg {
+ void __iomem *addr;
+ unsigned long mask;
+};
+
+struct combiner {
+ struct irq_domain *domain;
+ int parent_irq;
+ u32 nirqs;
+ u32 nregs;
+ struct combiner_reg regs[0];
+};
+
+static inline u32 irq_register(int irq)
+{
+ return irq / REG_SIZE;
+}
+
+static inline u32 irq_bit(int irq)
+{
+ return irq % REG_SIZE;
+
+}
+
+static inline int irq_nr(u32 reg, u32 bit)
+{
+ return reg * REG_SIZE + bit;
+}
+
+/*
+ * Handler for the cascaded IRQ.
+ */
+static void combiner_handle_irq(struct irq_desc *desc)
+{
+ struct combiner *combiner = irq_desc_get_handler_data(desc);
+ struct irq_chip *chip = irq_desc_get_chip(desc);
+ u32 reg;
+
+ chained_irq_enter(chip, desc);
+
+ for (reg = 0; reg < combiner->nregs; reg++) {
+ int virq;
+ int hwirq;
+ u32 bit;
+ u32 status;
+
+ if (combiner->regs[reg].mask == 0)
+ continue;
+
+ status = readl_relaxed(combiner->regs[reg].addr);
+ status &= combiner->regs[reg].mask;
+
+ while (status) {
+ bit = __ffs(status);
+ status &= ~(1 << bit);
+ hwirq = irq_nr(reg, bit);
+ virq = irq_find_mapping(combiner->domain, hwirq);
+ if (virq >= 0)
+ generic_handle_irq(virq);
+
+ }
+ }
+
+ chained_irq_exit(chip, desc);
+}
+
+/*
+ * irqchip callbacks
+ */
+
+static void combiner_irq_chip_mask_irq(struct irq_data *data)
+{
+ struct combiner *combiner = irq_data_get_irq_chip_data(data);
+ struct combiner_reg *reg = combiner->regs + irq_register(data->hwirq);
+
+ clear_bit(irq_bit(data->hwirq), &reg->mask);
+}
+
+static void combiner_irq_chip_unmask_irq(struct irq_data *data)
+{
+ struct combiner *combiner = irq_data_get_irq_chip_data(data);
+ struct combiner_reg *reg = combiner->regs + irq_register(data->hwirq);
+
+ set_bit(irq_bit(data->hwirq), &reg->mask);
+}
+
+static struct irq_chip irq_chip = {
+ .irq_mask = combiner_irq_chip_mask_irq,
+ .irq_unmask = combiner_irq_chip_unmask_irq,
+ .name = "qcom-irq-combiner"
+};
+
+/*
+ * irq_domain_ops callbacks
+ */
+
+static int combiner_irq_map(struct irq_domain *domain, unsigned int irq,
+ irq_hw_number_t hwirq)
+{
+ struct combiner *combiner = domain->host_data;
+
+ if (hwirq >= combiner->nirqs)
+ return -EINVAL;
+
+ irq_set_chip_and_handler(irq, &irq_chip, handle_level_irq);
+ irq_set_chip_data(irq, combiner);
+ irq_set_noprobe(irq);
+ return 0;
+}
+
+static void combiner_irq_unmap(struct irq_domain *domain, unsigned int irq)
+{
+ struct irq_data *data = irq_get_irq_data(irq);
+
+ if (WARN_ON(!data))
+ return;
+ irq_domain_reset_irq_data(data);
+}
+
+static int combiner_irq_translate(struct irq_domain *d, struct irq_fwspec *fws,
+ unsigned long *hwirq, unsigned int *type)
+{
+ if (is_acpi_node(fws->fwnode)) {
+ if (WARN_ON((fws->param_count != 2) ||
+ (fws->param[1] & IORESOURCE_IRQ_LOWEDGE) ||
+ (fws->param[1] & IORESOURCE_IRQ_HIGHEDGE)))
+ return -EINVAL;
+
+ *hwirq = fws->param[0];
+ *type = fws->param[1];
+ return 0;
+ }
+
+ return -EINVAL;
+}
+
+static const struct irq_domain_ops domain_ops = {
+ .map = combiner_irq_map,
+ .unmap = combiner_irq_unmap,
+ .translate = combiner_irq_translate
+};
+
+/*
+ * Device probing
+ */
+
+static acpi_status count_registers_cb(struct acpi_resource *ares, void *context)
+{
+ int *count = context;
+
+ if (ares->type == ACPI_RESOURCE_TYPE_GENERIC_REGISTER)
+ ++(*count);
+ return AE_OK;
+}
+
+static int count_registers(struct platform_device *pdev)
+{
+ struct acpi_device *adev = ACPI_COMPANION(&pdev->dev);
+ acpi_status status;
+ int count = 0;
+
+ if (!acpi_has_method(adev->handle, METHOD_NAME__CRS))
+ return -EINVAL;
+
+ status = acpi_walk_resources(adev->handle, METHOD_NAME__CRS,
+ count_registers_cb, &count);
+ if (ACPI_FAILURE(status))
+ return -EINVAL;
+ return count;
+}
+
+struct get_registers_context {
+ struct device *dev;
+ struct combiner *combiner;
+ int err;
+};
+
+static acpi_status get_registers_cb(struct acpi_resource *ares, void *context)
+{
+ struct get_registers_context *ctx = context;
+ struct acpi_resource_generic_register *reg;
+ phys_addr_t paddr;
+ void __iomem *vaddr;
+
+ if (ares->type != ACPI_RESOURCE_TYPE_GENERIC_REGISTER)
+ return AE_OK;
+
+ reg = &ares->data.generic_reg;
+ paddr = reg->address;
+ if ((reg->space_id != ACPI_SPACE_MEM) ||
+ (reg->bit_offset != 0) ||
+ (reg->bit_width > REG_SIZE)) {
+ dev_err(ctx->dev, "Bad register resource @%pa\n", &paddr);
+ ctx->err = -EINVAL;
+ return AE_ERROR;
+ }
+
+ vaddr = devm_ioremap(ctx->dev, reg->address, REG_SIZE);
+ if (IS_ERR(vaddr)) {
+ dev_err(ctx->dev, "Can't map register @%pa\n", &paddr);
+ ctx->err = PTR_ERR(vaddr);
+ return AE_ERROR;
+ }
+
+ ctx->combiner->regs[ctx->combiner->nregs].addr = vaddr;
+ ctx->combiner->nirqs += reg->bit_width;
+ ctx->combiner->nregs++;
+ return AE_OK;
+}
+
+static int get_registers(struct platform_device *pdev, struct combiner *comb)
+{
+ struct acpi_device *adev = ACPI_COMPANION(&pdev->dev);
+ acpi_status status;
+ struct get_registers_context ctx;
+
+ if (!acpi_has_method(adev->handle, METHOD_NAME__CRS))
+ return -EINVAL;
+
+ ctx.dev = &pdev->dev;
+ ctx.combiner = comb;
+ ctx.err = 0;
+
+ status = acpi_walk_resources(adev->handle, METHOD_NAME__CRS,
+ get_registers_cb, &ctx);
+ if (ACPI_FAILURE(status))
+ return ctx.err;
+ return 0;
+}
+
+static int __init combiner_probe(struct platform_device *pdev)
+{
+ struct combiner *combiner;
+ size_t alloc_sz;
+ u32 nregs;
+ int err;
+
+ nregs = count_registers(pdev);
+ if (nregs <= 0) {
+ dev_err(&pdev->dev, "Error reading register resources\n");
+ return -EINVAL;
+ }
+
+ alloc_sz = sizeof(*combiner) + sizeof(struct combiner_reg) * nregs;
+ combiner = devm_kzalloc(&pdev->dev, alloc_sz, GFP_KERNEL);
+ if (!combiner)
+ return -ENOMEM;
+
+ err = get_registers(pdev, combiner);
+ if (err < 0)
+ return err;
+
+ combiner->parent_irq = platform_get_irq(pdev, 0);
+ if (combiner->parent_irq <= 0) {
+ dev_err(&pdev->dev, "Error getting IRQ resource\n");
+ return -EPROBE_DEFER;
+ }
+
+ combiner->domain = irq_domain_create_linear(pdev->dev.fwnode, combiner->nirqs,
+ &domain_ops, combiner);
+ if (!combiner->domain)
+ /* Errors printed by irq_domain_create_linear */
+ return -ENODEV;
+
+ irq_set_chained_handler_and_data(combiner->parent_irq,
+ combiner_handle_irq, combiner);
+
+ dev_info(&pdev->dev, "Initialized with [p=%d,n=%d,r=%p]\n",
+ combiner->parent_irq, combiner->nirqs, combiner->regs[0].addr);
+ return 0;
+}
+
+static const struct acpi_device_id qcom_irq_combiner_acpi_match[] = {
+ { "QCOM80B1", },
+ { }
+};
+
+static struct platform_driver qcom_irq_combiner_probe = {
+ .driver = {
+ .name = "qcom-irq-combiner",
+ .owner = THIS_MODULE,
+ .acpi_match_table = ACPI_PTR(qcom_irq_combiner_acpi_match),
+ },
+ .probe = combiner_probe,
+};
+
+static int __init register_qcom_irq_combiner(void)
+{
+ return platform_driver_register(&qcom_irq_combiner_probe);
+}
+device_initcall(register_qcom_irq_combiner);
--
Qualcomm Datacenter Technologies, Inc. on behalf of the Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.

2016-12-16 16:23:23

by Lorenzo Pieralisi

[permalink] [raw]
Subject: Re: [PATCH V9 1/3] ACPI: Generic GSI: Do not attempt to map non-GSI IRQs during bus scan

On Wed, Dec 14, 2016 at 05:10:36PM -0500, Agustin Vega-Frias wrote:
> ACPI extended IRQ resources may contain a Resource Source field to specify
> an alternate interrupt controller, attempting to map them as GSIs is
> incorrect, so just disable the platform resource.
>
> Since this field is currently ignored, we make this change conditional
> on CONFIG_ACPI_GENERIC_GSI to keep the current behavior on x86 platforms,
> in case some existing ACPI tables are using this incorrectly.
>
> Signed-off-by: Agustin Vega-Frias <[email protected]>
> ---
> drivers/acpi/resource.c | 17 ++++++++++++++++-
> 1 file changed, 16 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/acpi/resource.c b/drivers/acpi/resource.c
> index 56241eb..76ca4e9 100644
> --- a/drivers/acpi/resource.c
> +++ b/drivers/acpi/resource.c
> @@ -43,6 +43,18 @@ static inline bool acpi_iospace_resource_valid(struct resource *res)
> acpi_iospace_resource_valid(struct resource *res) { return true; }
> #endif
>
> +#ifdef CONFIG_ACPI_GENERIC_GSI
> +static inline bool is_gsi(struct acpi_resource_extended_irq *ext_irq)
> +{
> + return ext_irq->resource_source.string_length == 0;
> +}
> +#else
> +static inline bool is_gsi(struct acpi_resource_extended_irq *ext_irq)
> +{
> + return true;
> +}
> +#endif

Well, patch is simple there is not much to say other that on the
firmware side I honestly do not see many options, either we remove the
ifdeffery above and make the check unconditional (ie we do check on
x86/ia64 too instead of always returning true) and see if things hold up
on x86 (at least we try) or we will never know and will never be able to
use this on x86 if there will ever be need.

It would be certainly weird to find out that a descriptor has a
resource_source pointer put there by mistake (because that's what we are
talking about, things work on x86/ia64 by ignoring the resource_source
pointer so any string there is just an unfortunate mistake AFAICS).

I am quite tempted to remove the ifdef and make the is_gsi() check effective on
x86/ia64 too.

Lorenzo

> +
> static bool acpi_dev_resource_len_valid(u64 start, u64 end, u64 len, bool io)
> {
> u64 reslen = end - start + 1;
> @@ -470,9 +482,12 @@ bool acpi_dev_resource_interrupt(struct acpi_resource *ares, int index,
> acpi_dev_irqresource_disabled(res, 0);
> return false;
> }
> - acpi_dev_get_irqresource(res, ext_irq->interrupts[index],
> + if (is_gsi(ext_irq))
> + acpi_dev_get_irqresource(res, ext_irq->interrupts[index],
> ext_irq->triggering, ext_irq->polarity,
> ext_irq->sharable, false);
> + else
> + acpi_dev_irqresource_disabled(res, 0);
> break;
> default:
> res->flags = 0;
> --
> Qualcomm Datacenter Technologies, Inc. on behalf of the Qualcomm Technologies, Inc.
> Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.
>

2016-12-16 16:30:52

by Agustin Vega-Frias

[permalink] [raw]
Subject: Re: [PATCH V9 1/3] ACPI: Generic GSI: Do not attempt to map non-GSI IRQs during bus scan

Hi Lorenzo,

On 2016-12-16 11:24, Lorenzo Pieralisi wrote:
> On Wed, Dec 14, 2016 at 05:10:36PM -0500, Agustin Vega-Frias wrote:
>> ACPI extended IRQ resources may contain a Resource Source field to
>> specify
>> an alternate interrupt controller, attempting to map them as GSIs is
>> incorrect, so just disable the platform resource.
>>
>> Since this field is currently ignored, we make this change conditional
>> on CONFIG_ACPI_GENERIC_GSI to keep the current behavior on x86
>> platforms,
>> in case some existing ACPI tables are using this incorrectly.
>>
>> Signed-off-by: Agustin Vega-Frias <[email protected]>
>> ---
>> drivers/acpi/resource.c | 17 ++++++++++++++++-
>> 1 file changed, 16 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/acpi/resource.c b/drivers/acpi/resource.c
>> index 56241eb..76ca4e9 100644
>> --- a/drivers/acpi/resource.c
>> +++ b/drivers/acpi/resource.c
>> @@ -43,6 +43,18 @@ static inline bool
>> acpi_iospace_resource_valid(struct resource *res)
>> acpi_iospace_resource_valid(struct resource *res) { return true; }
>> #endif
>>
>> +#ifdef CONFIG_ACPI_GENERIC_GSI
>> +static inline bool is_gsi(struct acpi_resource_extended_irq *ext_irq)
>> +{
>> + return ext_irq->resource_source.string_length == 0;
>> +}
>> +#else
>> +static inline bool is_gsi(struct acpi_resource_extended_irq *ext_irq)
>> +{
>> + return true;
>> +}
>> +#endif
>
> Well, patch is simple there is not much to say other that on the
> firmware side I honestly do not see many options, either we remove the
> ifdeffery above and make the check unconditional (ie we do check on
> x86/ia64 too instead of always returning true) and see if things hold
> up
> on x86 (at least we try) or we will never know and will never be able
> to
> use this on x86 if there will ever be need.
>
> It would be certainly weird to find out that a descriptor has a
> resource_source pointer put there by mistake (because that's what we
> are
> talking about, things work on x86/ia64 by ignoring the resource_source
> pointer so any string there is just an unfortunate mistake AFAICS).
>
> I am quite tempted to remove the ifdef and make the is_gsi() check
> effective on
> x86/ia64 too.

I wouldn't be opposed to that. I added the #ifdef out of abundance of
caution,
but if the x86 folks agree and we can get sufficient testing to ensure
this
doesn't break anything I'd like to remove it too.

Thanks,
Agustin

>
> Lorenzo
>
>> +
>> static bool acpi_dev_resource_len_valid(u64 start, u64 end, u64 len,
>> bool io)
>> {
>> u64 reslen = end - start + 1;
>> @@ -470,9 +482,12 @@ bool acpi_dev_resource_interrupt(struct
>> acpi_resource *ares, int index,
>> acpi_dev_irqresource_disabled(res, 0);
>> return false;
>> }
>> - acpi_dev_get_irqresource(res, ext_irq->interrupts[index],
>> + if (is_gsi(ext_irq))
>> + acpi_dev_get_irqresource(res, ext_irq->interrupts[index],
>> ext_irq->triggering, ext_irq->polarity,
>> ext_irq->sharable, false);
>> + else
>> + acpi_dev_irqresource_disabled(res, 0);
>> break;
>> default:
>> res->flags = 0;
>> --
>> Qualcomm Datacenter Technologies, Inc. on behalf of the Qualcomm
>> Technologies, Inc.
>> Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a
>> Linux Foundation Collaborative Project.
>>

--
Qualcomm Datacenter Technologies, Inc. on behalf of the Qualcomm
Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a
Linux Foundation Collaborative Project.