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 <agustinv@xxxxxxxxxxxxxx>
---
drivers/acpi/Makefile | 2 +-
drivers/acpi/{gsi.c => irq.c} | 221 ++++++++++++++++++++++++++++++++++++++
drivers/base/platform.c | 8 ++
include/asm-generic/vmlinux.lds.h | 1 +
include/linux/acpi.h | 15 +++
5 files changed, 246 insertions(+), 1 deletion(-)
rename drivers/acpi/{gsi.c => irq.c} (28%)
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 28%
rename from drivers/acpi/gsi.c
rename to drivers/acpi/irq.c
index ee9e0f2..db4ee4c 100644
--- a/drivers/acpi/gsi.c
+++ b/drivers/acpi/irq.c
@@ -85,6 +85,227 @@ void acpi_unregister_gsi(u32 gsi)
EXPORT_SYMBOL_GPL(acpi_unregister_gsi);
/**
+ * acpi_get_irq_source_fwhandle() - Retrieve fwhandle from IRQ resource source.
+ * @source: acpi_resource_source to use for the lookup.
+ *
+ * Description:
+ * Retrieve the fwhandle of the device referenced by the given IRQ resource
+ * source. In addition to it being a valid ACPI device, its _HID must be
+ * listed on the probe table of ACPI DSDT irqchips. The check is used to
+ * determine if a driver for the referenced device is available and decide
+ * if we should try deferred probing if the device has not been probed yet.
+ * Drivers must use the __dsdt_irqchip attribute when declaring the table
+ * of acpi_device_ids for the device, e.g.:
+ *
+ * static const struct acpi_device_id my_device_ids[] __dsdt_irqchip = {
+ * { "ABCD0123", },
+ * { }
+ * };
+ *
+ * Return:
+ * The referenced device fwhandle or NULL on failure
+ */
+static struct fwnode_handle *
+acpi_get_irq_source_fwhandle(const struct acpi_resource_source *source)
+{
+ struct fwnode_handle *result = NULL;
+ struct acpi_device *device;
+ struct acpi_hardware_id *hwid;
+ struct acpi_device_id *devid;
+ 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 (WARN_ON(ACPI_FAILURE(status)))
+ return NULL;
+
+ device = acpi_bus_get_acpi_device(handle);
+ if (WARN_ON(!device))
+ return NULL;
+
+ list_for_each_entry(hwid, &device->pnp.ids, list) {
+ for (devid = &__dsdt_irqchip_acpi_probe_table;
+ devid < &__dsdt_irqchip_acpi_probe_table_end; devid++) {
+ if (devid->id && !strcmp(devid->id, hwid->id)) {
+ result = &device->fwnode;
+ break;
+ }
+ }
+ }
+
+ acpi_bus_put_acpi_device(device);
+
+ return result;
+}
+
+/*
+ * Context for the resource walk used to lookup IRQ resources.
+ * Contains a return code, the lookup index, and references to the flags
+ * and fwspec where the result is returned.
+ */
+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.
+ * @fwnode: matching fwnode
+ * @hwirq: hardware IRQ number
+ * @triggering: triggering attributes of hwirq
+ * @polarity: polarity attributes of hwirq
+ * @polarity: polarity attributes of hwirq
+ * @shareable: shareable attributes of hwirq
+ * @ctx: acpi_irq_parse_one_ctx updated by this function
+ *
+ * Description:
+ * Handle a matching IRQ resource by populating the given ctx with
+ * the information passed.
+ */
+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)
+{
+ if (!fwnode)
+ return;
+ 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
+ *
+ * Description:
+ * 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 (eirq->producer_consumer == ACPI_PRODUCER)
+ return AE_OK;
+ 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
+ *
+ * Description:
+ * Resolves an interrupt for a device by walking its CRS resources to find
+ * the appropriate ACPI IRQ resource and populating the given struct irq_fwspec
+ * and flags.
+ *
+ * Return:
+ * The result stored in ctx.rc by the callback, or the default -EINVAL value
+ * if an error occurs.
+ */
+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_walk_resources(handle, METHOD_NAME__CRS, acpi_irq_parse_one_cb, &ctx);
+ return ctx.rc;
+}
+
+/**
+ * acpi_irq_get - Lookup an ACPI IRQ resource and use it to initialize resource.
+ * @handle: ACPI device handle
+ * @index: ACPI IRQ resource index to lookup
+ * @res: Linux IRQ resource to initialize
+ *
+ * Description:
+ * Look for the ACPI IRQ resource with the given index and use it to initialize
+ * the given Linux IRQ resource.
+ *
+ * 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)
+{
+ struct irq_fwspec fwspec;
+ struct irq_domain *domain;
+ unsigned long flags;
+ int rc;
+
+ 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..040d474 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 && has_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
diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index 0968d13..0763c8a 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -567,6 +567,7 @@
ACPI_PROBE_TABLE(irqchip) \
ACPI_PROBE_TABLE(clksrc) \
ACPI_PROBE_TABLE(iort) \
+ ACPI_PROBE_TABLE(dsdt_irqchip) \
EARLYCON_TABLE()
#define INIT_TEXT \
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 5b36974..15fac1a 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -1056,6 +1056,11 @@ struct acpi_probe_entry {
(&ACPI_PROBE_TABLE_END(t) - \
&ACPI_PROBE_TABLE(t))); \
})
+
+#define __dsdt_irqchip __section(__dsdt_irqchip_acpi_probe_table)
+extern struct acpi_device_id __dsdt_irqchip_acpi_probe_table;
+extern struct acpi_device_id __dsdt_irqchip_acpi_probe_table_end;
+
#else
static inline int acpi_dev_get_property(struct acpi_device *adev,
const char *name, acpi_object_type type,
@@ -1153,4 +1158,14 @@ 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*/
--
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Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.
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