[PATCH V8 1/3] ACPI: Add support for ResourceSource/IRQ domain mapping

Agustin Vega-Frias
2016-11-29T22:57:57Z

When an Extended IRQ Resource contains a valid ResourceSource
use it to map the IRQ on the domain associated with the ACPI
device referenced.

With this in place an irqchip driver can create its domain using
irq_domain_create_linear and pass the device fwnode to create
the domain mapping. When dependent devices are probed these
changes allow the ACPI core find the domain and map the IRQ.

Signed-off-by: Agustin Vega-Frias <agustinv@codeaurora.org>
---
drivers/acpi/Makefile | 2 +-
drivers/acpi/{gsi.c => irq.c} | 99 +++++++++++++++++++++++++++++++++++++------
drivers/acpi/resource.c | 29 +++++++------
include/linux/acpi.h | 19 +++++++++
4 files changed, 122 insertions(+), 27 deletions(-)
rename drivers/acpi/{gsi.c => irq.c} (52%)

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 52%
rename from drivers/acpi/gsi.c
rename to drivers/acpi/irq.c
index ee9e0f2..e82eb6e 100644
--- a/drivers/acpi/gsi.c
+++ b/drivers/acpi/irq.c
@@ -18,6 +18,45 @@
static struct fwnode_handle *acpi_gsi_domain_id;

/**
+ * acpi_get_irq_source_fwhandle() - Retrieve the fwhandle of the given
+ * acpi_resource_source which is used
+ * to be 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
+ */
+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;
+}
+EXPORT_SYMBOL_GPL(acpi_get_irq_source_fwhandle);
+
+/**
* acpi_gsi_to_irq() - Retrieve the linux irq number for a given GSI
* @gsi: GSI IRQ number to map
* @irq: pointer where linux IRQ number is stored
@@ -42,6 +81,51 @@ int acpi_gsi_to_irq(u32 gsi, unsigned int *irq)
EXPORT_SYMBOL_GPL(acpi_gsi_to_irq);

/**
+ * acpi_register_irq() - Map a hardware to a linux IRQ number
+ * @source: IRQ source
+ * @hwirq: Hardware IRQ number
+ * @trigger: trigger type of the IRQ number to be mapped
+ * @polarity: polarity of the IRQ to be mapped
+ *
+ * Returns: a valid linux IRQ number on success
+ * -EINVAL on failure
+ * -EPROBE_DEFER if the IRQ domain lookup failed
+ */
+int acpi_register_irq(struct fwnode_handle *source, u32 hwirq, int trigger,
+ int polarity)
+{
+ struct irq_fwspec fwspec;
+
+ if (!source)
+ source = acpi_gsi_domain_id;
+
+ if (irq_find_matching_fwnode(source, DOMAIN_BUS_ANY) == NULL)
+ return -EPROBE_DEFER;
+
+ fwspec.fwnode = source;
+ fwspec.param[0] = hwirq;
+ fwspec.param[1] = acpi_dev_get_irq_type(trigger, polarity);
+ fwspec.param_count = 2;
+
+ return irq_create_fwspec_mapping(&fwspec);
+}
+EXPORT_SYMBOL_GPL(acpi_register_irq);
+
+/**
+ * acpi_unregister_irq() - Free a Hardware IRQ<->linux IRQ number mapping
+ * @hwirq: Hardware IRQ number
+ */
+void acpi_unregister_irq(struct fwnode_handle *source, u32 hwirq)
+{
+ struct irq_domain *d = irq_find_matching_fwnode(source,
+ DOMAIN_BUS_ANY);
+ int irq = irq_find_mapping(d, hwirq);
+
+ irq_dispose_mapping(irq);
+}
+EXPORT_SYMBOL_GPL(acpi_unregister_irq);
+
+/**
* acpi_register_gsi() - Map a GSI to a linux IRQ number
* @dev: device for which IRQ has to be mapped
* @gsi: GSI IRQ number
@@ -54,19 +138,12 @@ int acpi_gsi_to_irq(u32 gsi, unsigned int *irq)
int acpi_register_gsi(struct device *dev, u32 gsi, int trigger,
int polarity)
{
- struct irq_fwspec fwspec;
-
if (WARN_ON(!acpi_gsi_domain_id)) {
pr_warn("GSI: No registered irqchip, giving up\n");
return -EINVAL;
}

- fwspec.fwnode = acpi_gsi_domain_id;
- fwspec.param[0] = gsi;
- fwspec.param[1] = acpi_dev_get_irq_type(trigger, polarity);
- fwspec.param_count = 2;
-
- return irq_create_fwspec_mapping(&fwspec);
+ return acpi_register_irq(acpi_gsi_domain_id, gsi, trigger, polarity);
}
EXPORT_SYMBOL_GPL(acpi_register_gsi);

@@ -76,11 +153,7 @@ int acpi_register_gsi(struct device *dev, u32 gsi, int trigger,
*/
void acpi_unregister_gsi(u32 gsi)
{
- struct irq_domain *d = irq_find_matching_fwnode(acpi_gsi_domain_id,
- DOMAIN_BUS_ANY);
- int irq = irq_find_mapping(d, gsi);
-
- irq_dispose_mapping(irq);
+ acpi_unregister_irq(acpi_gsi_domain_id, gsi);
}
EXPORT_SYMBOL_GPL(acpi_unregister_gsi);

diff --git a/drivers/acpi/resource.c b/drivers/acpi/resource.c
index 56241eb..98b94eb 100644
--- a/drivers/acpi/resource.c
+++ b/drivers/acpi/resource.c
@@ -374,21 +374,22 @@ unsigned int acpi_dev_get_irq_type(int triggering, int polarity)
}
EXPORT_SYMBOL_GPL(acpi_dev_get_irq_type);

-static void acpi_dev_irqresource_disabled(struct resource *res, u32 gsi)
+static void acpi_dev_irqresource_disabled(struct resource *res, u32 hwirq)
{
- res->start = gsi;
- res->end = gsi;
+ res->start = hwirq;
+ res->end = hwirq;
res->flags = IORESOURCE_IRQ | IORESOURCE_DISABLED | IORESOURCE_UNSET;
}

-static void acpi_dev_get_irqresource(struct resource *res, u32 gsi,
+static void acpi_dev_get_irqresource(struct resource *res, u32 hwirq,
+ struct fwnode_handle *source,
u8 triggering, u8 polarity, u8 shareable,
bool legacy)
{
int irq, p, t;

- if (!valid_IRQ(gsi)) {
- acpi_dev_irqresource_disabled(res, gsi);
+ if (!source && !valid_IRQ(hwirq)) {
+ acpi_dev_irqresource_disabled(res, hwirq);
return;
}

@@ -402,25 +403,25 @@ static void acpi_dev_get_irqresource(struct resource *res, u32 gsi,
* using extended IRQ descriptors we take the IRQ configuration
* from _CRS directly.
*/
- if (legacy && !acpi_get_override_irq(gsi, &t, &p)) {
+ if (legacy && !acpi_get_override_irq(hwirq, &t, &p)) {
u8 trig = t ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE;
u8 pol = p ? ACPI_ACTIVE_LOW : ACPI_ACTIVE_HIGH;

if (triggering != trig || polarity != pol) {
- pr_warning("ACPI: IRQ %d override to %s, %s\n", gsi,
- t ? "level" : "edge", p ? "low" : "high");
+ pr_warn("ACPI: IRQ %d override to %s, %s\n", hwirq,
+ t ? "level" : "edge", p ? "low" : "high");
triggering = trig;
polarity = pol;
}
}

res->flags = acpi_dev_irq_flags(triggering, polarity, shareable);
- irq = acpi_register_gsi(NULL, gsi, triggering, polarity);
+ irq = acpi_register_irq(source, hwirq, triggering, polarity);
if (irq >= 0) {
res->start = irq;
res->end = irq;
} else {
- acpi_dev_irqresource_disabled(res, gsi);
+ acpi_dev_irqresource_disabled(res, hwirq);
}
}

@@ -448,6 +449,7 @@ bool acpi_dev_resource_interrupt(struct acpi_resource *ares, int index,
{
struct acpi_resource_irq *irq;
struct acpi_resource_extended_irq *ext_irq;
+ struct fwnode_handle *src;

switch (ares->type) {
case ACPI_RESOURCE_TYPE_IRQ:
@@ -460,7 +462,7 @@ bool acpi_dev_resource_interrupt(struct acpi_resource *ares, int index,
acpi_dev_irqresource_disabled(res, 0);
return false;
}
- acpi_dev_get_irqresource(res, irq->interrupts[index],
+ acpi_dev_get_irqresource(res, irq->interrupts[index], NULL,
irq->triggering, irq->polarity,
irq->sharable, true);
break;
@@ -470,7 +472,8 @@ 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],
+ src = acpi_get_irq_source_fwhandle(&ext_irq->resource_source);
+ acpi_dev_get_irqresource(res, ext_irq->interrupts[index], src,
ext_irq->triggering, ext_irq->polarity,
ext_irq->sharable, false);
break;
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 61a3d90..154e576 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -321,6 +321,25 @@ void acpi_set_irq_model(enum acpi_irq_model_id model,
*/
void acpi_unregister_gsi (u32 gsi);

+#ifdef CONFIG_ACPI_GENERIC_GSI
+struct fwnode_handle *
+acpi_get_irq_source_fwhandle(const struct acpi_resource_source *source);
+int acpi_register_irq(struct fwnode_handle *source, u32 hwirq, int trigger,
+ int polarity);
+void acpi_unregister_irq(struct fwnode_handle *source, u32 hwirq);
+#else
+#define acpi_get_irq_source_fwhandle(source) (NULL)
+static inline int acpi_register_irq(struct fwnode_handle *source, u32 hwirq,
+ int trigger, int polarity)
+{
+ return acpi_register_gsi(NULL, hwirq, trigger, polarity);
+}
+static inline void acpi_unregister_irq(struct fwnode_handle *source, u32 hwirq)
+{
+ acpi_unregister_gsi(hwirq);
+}
+#endif
+
struct pci_dev;

int acpi_pci_irq_enable (struct pci_dev *dev);
--
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