298 строки
8.2 KiB
C
298 строки
8.2 KiB
C
/*
|
|
* ACPI GSI IRQ layer
|
|
*
|
|
* Copyright (C) 2015 ARM Ltd.
|
|
* Author: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*/
|
|
#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_gsi_domain_id;
|
|
|
|
/**
|
|
* 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 = irq_find_matching_fwnode(acpi_gsi_domain_id,
|
|
DOMAIN_BUS_ANY);
|
|
|
|
*irq = irq_find_mapping(d, gsi);
|
|
/*
|
|
* *irq == 0 means no mapping, that should
|
|
* be reported as a failure
|
|
*/
|
|
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;
|
|
|
|
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);
|
|
}
|
|
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 = irq_find_matching_fwnode(acpi_gsi_domain_id,
|
|
DOMAIN_BUS_ANY);
|
|
int 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.
|
|
*
|
|
* 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
|
|
* GSI interrupts
|
|
*/
|
|
void __init acpi_set_irq_model(enum acpi_irq_model_id model,
|
|
struct fwnode_handle *fwnode)
|
|
{
|
|
acpi_irq_model = model;
|
|
acpi_gsi_domain_id = fwnode;
|
|
}
|