// 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;
unsigned int irq;
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;
irq = irq_create_fwspec_mapping(&fwspec);
if (!irq)
return -EINVAL;
return irq;
}
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);