[PATCH V12 2/3] ACPI: Add support for ResourceSource/IRQ domain mapping
Lorenzo Pieralisi
lorenzo.pieralisi at arm.com
Fri Feb 3 01:02:10 PST 2017
On Thu, Feb 02, 2017 at 06:23:58PM -0500, Agustin Vega-Frias wrote:
> 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.
>
> Acked-by: Rafael J. Wysocki <rafael at kernel.org>
> Signed-off-by: Agustin Vega-Frias <agustinv at codeaurora.org>
> ---
> drivers/acpi/Makefile | 2 +-
> drivers/acpi/{gsi.c => irq.c} | 199 ++++++++++++++++++++++++++++++++++++++++++
> drivers/base/platform.c | 10 +++
> include/linux/acpi.h | 10 +++
> 4 files changed, 220 insertions(+), 1 deletion(-)
> rename drivers/acpi/{gsi.c => irq.c} (31%)
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi at arm.com>
> 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 31%
> rename from drivers/acpi/gsi.c
> rename to drivers/acpi/irq.c
> index ee9e0f2..830299a 100644
> --- a/drivers/acpi/gsi.c
> +++ b/drivers/acpi/irq.c
> @@ -85,6 +85,205 @@ 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.
> + *
> + * 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;
> + 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 (WARN_ON(ACPI_FAILURE(status)))
> + return NULL;
> +
> + device = acpi_bus_get_acpi_device(handle);
> + if (WARN_ON(!device))
> + return NULL;
> +
> + result = &device->fwnode;
> + 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..647e476 100644
> --- a/drivers/base/platform.c
> +++ b/drivers/base/platform.c
> @@ -102,6 +102,16 @@ int platform_get_irq(struct platform_device *dev, unsigned int num)
> }
>
> r = platform_get_resource(dev, IORESOURCE_IRQ, num);
> + if (has_acpi_companion(&dev->dev)) {
> + if (r && r->flags & IORESOURCE_DISABLED) {
> + 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/linux/acpi.h b/include/linux/acpi.h
> index 5b36974..8e577c2 100644
> --- a/include/linux/acpi.h
> +++ b/include/linux/acpi.h
> @@ -1153,4 +1153,14 @@ static inline void acpi_table_upgrade(void) { }
> static inline int parse_spcr(bool earlycon) { return 0; }
> #endif
>
> +#if IS_ENABLED(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.
>
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