| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * ACPI GSI IRQ layer |
| * |
| * Copyright (C) 2015 ARM Ltd. |
| * Author: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> |
| */ |
| #include <linux/acpi.h> |
| #include <linux/irq.h> |
| #include <linux/irqdomain.h> |
| #include <linux/of.h> |
| |
| enum acpi_irq_model_id acpi_irq_model; |
| |
| static struct fwnode_handle *(*acpi_get_gsi_domain_id)(u32 gsi); |
| static u32 (*acpi_gsi_to_irq_fallback)(u32 gsi); |
| |
| /** |
| * 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 |
| * |
| * irq location updated with irq value [>0 on success, 0 on failure] |
| * |
| * Returns: 0 on success |
| * -EINVAL on failure |
| */ |
| int acpi_gsi_to_irq(u32 gsi, unsigned int *irq) |
| { |
| struct irq_domain *d; |
| |
| d = irq_find_matching_fwnode(acpi_get_gsi_domain_id(gsi), |
| DOMAIN_BUS_ANY); |
| *irq = irq_find_mapping(d, gsi); |
| /* |
| * *irq == 0 means no mapping, that should be reported as a |
| * failure, unless there is an arch-specific fallback handler. |
| */ |
| if (!*irq && acpi_gsi_to_irq_fallback) |
| *irq = acpi_gsi_to_irq_fallback(gsi); |
| |
| return (*irq > 0) ? 0 : -EINVAL; |
| } |
| EXPORT_SYMBOL_GPL(acpi_gsi_to_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 |
| * @trigger: trigger type of the GSI number to be mapped |
| * @polarity: polarity of the GSI to be mapped |
| * |
| * Returns: a valid linux IRQ number on success |
| * -EINVAL on failure |
| */ |
| int acpi_register_gsi(struct device *dev, u32 gsi, int trigger, |
| int polarity) |
| { |
| struct irq_fwspec fwspec; |
| |
| fwspec.fwnode = acpi_get_gsi_domain_id(gsi); |
| if (WARN_ON(!fwspec.fwnode)) { |
| pr_warn("GSI: No registered irqchip, giving up\n"); |
| return -EINVAL; |
| } |
| |
| fwspec.param[0] = gsi; |
| 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_gsi); |
| |
| /** |
| * acpi_unregister_gsi() - Free a GSI<->linux IRQ number mapping |
| * @gsi: GSI IRQ number |
| */ |
| void acpi_unregister_gsi(u32 gsi) |
| { |
| struct irq_domain *d; |
| int irq; |
| |
| if (WARN_ON(acpi_irq_model == ACPI_IRQ_MODEL_GIC && gsi < 16)) |
| return; |
| |
| d = irq_find_matching_fwnode(acpi_get_gsi_domain_id(gsi), |
| DOMAIN_BUS_ANY); |
| irq = irq_find_mapping(d, gsi); |
| irq_dispose_mapping(irq); |
| } |
| 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. |
| * @gsi: GSI IRQ number |
| * |
| * 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, |
| u32 gsi) |
| { |
| struct fwnode_handle *result; |
| struct acpi_device *device; |
| acpi_handle handle; |
| acpi_status status; |
| |
| if (!source->string_length) |
| return acpi_get_gsi_domain_id(gsi); |
| |
| status = acpi_get_handle(NULL, source->string_ptr, &handle); |
| if (WARN_ON(ACPI_FAILURE(status))) |
| return NULL; |
| |
| device = acpi_get_acpi_dev(handle); |
| if (WARN_ON(!device)) |
| return NULL; |
| |
| result = &device->fwnode; |
| acpi_put_acpi_dev(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 |
| * @wake_capable: wake capable attribute 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, |
| u8 wake_capable, |
| struct acpi_irq_parse_one_ctx *ctx) |
| { |
| if (!fwnode) |
| return; |
| ctx->rc = 0; |
| *ctx->res_flags = acpi_dev_irq_flags(triggering, polarity, shareable, wake_capable); |
| 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_get_gsi_domain_id(irq->interrupts[ctx->index]); |
| acpi_irq_parse_one_match(fwnode, irq->interrupts[ctx->index], |
| irq->triggering, irq->polarity, |
| irq->shareable, irq->wake_capable, 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, |
| eirq->interrupts[ctx->index]); |
| acpi_irq_parse_one_match(fwnode, eirq->interrupts[ctx->index], |
| eirq->triggering, eirq->polarity, |
| eirq->shareable, eirq->wake_capable, 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 |
| * @fn: a dispatcher function that will return the domain fwnode |
| * for a given GSI |
| */ |
| void __init acpi_set_irq_model(enum acpi_irq_model_id model, |
| struct fwnode_handle *(*fn)(u32)) |
| { |
| acpi_irq_model = model; |
| acpi_get_gsi_domain_id = fn; |
| } |
| |
| /** |
| * acpi_set_gsi_to_irq_fallback - Register a GSI transfer |
| * callback to fallback to arch specified implementation. |
| * @fn: arch-specific fallback handler |
| */ |
| void __init acpi_set_gsi_to_irq_fallback(u32 (*fn)(u32)) |
| { |
| acpi_gsi_to_irq_fallback = fn; |
| } |
| |
| /** |
| * acpi_irq_create_hierarchy - Create a hierarchical IRQ domain with the default |
| * GSI domain as its parent. |
| * @flags: Irq domain flags associated with the domain |
| * @size: Size of the domain. |
| * @fwnode: Optional fwnode of the interrupt controller |
| * @ops: Pointer to the interrupt domain callbacks |
| * @host_data: Controller private data pointer |
| */ |
| struct irq_domain *acpi_irq_create_hierarchy(unsigned int flags, |
| unsigned int size, |
| struct fwnode_handle *fwnode, |
| const struct irq_domain_ops *ops, |
| void *host_data) |
| { |
| struct irq_domain *d; |
| |
| /* This only works for the GIC model... */ |
| if (acpi_irq_model != ACPI_IRQ_MODEL_GIC) |
| return NULL; |
| |
| d = irq_find_matching_fwnode(acpi_get_gsi_domain_id(0), |
| DOMAIN_BUS_ANY); |
| |
| if (!d) |
| return NULL; |
| |
| return irq_domain_create_hierarchy(d, flags, size, fwnode, ops, |
| host_data); |
| } |
| EXPORT_SYMBOL_GPL(acpi_irq_create_hierarchy); |