genirq: Add generic msi irq domain support

Implement the basic functions for MSI interrupt support with
hierarchical interrupt domains.

[ tglx: Extracted and combined from several patches ]

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Yingjoe Chen <yingjoe.chen@mediatek.com>
Cc: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Jiang Liu 2014-11-12 11:39:03 +01:00 committed by Thomas Gleixner
parent 9dde55b72d
commit f3cf8bb0d6
4 changed files with 197 additions and 0 deletions

View File

@ -114,4 +114,49 @@ struct msi_controller {
void (*teardown_irq)(struct msi_controller *chip, unsigned int irq);
};
#ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
struct irq_domain;
struct irq_chip;
struct device_node;
struct msi_domain_info;
/**
* struct msi_domain_ops - MSI interrupt domain callbacks
* @get_hwirq: Retrieve the resulting hw irq number
* @msi_init: Domain specific init function for MSI interrupts
* @msi_free: Domain specific function to free a MSI interrupts
*/
struct msi_domain_ops {
irq_hw_number_t (*get_hwirq)(struct msi_domain_info *info, void *arg);
int (*msi_init)(struct irq_domain *domain,
struct msi_domain_info *info,
unsigned int virq, irq_hw_number_t hwirq,
void *arg);
void (*msi_free)(struct irq_domain *domain,
struct msi_domain_info *info,
unsigned int virq);
};
/**
* struct msi_domain_info - MSI interrupt domain data
* @ops: The callback data structure
* @chip: The associated interrupt chip
* @data: Domain specific data
*/
struct msi_domain_info {
struct msi_domain_ops *ops;
struct irq_chip *chip;
void *data;
};
int msi_domain_set_affinity(struct irq_data *data, const struct cpumask *mask,
bool force);
struct irq_domain *msi_create_irq_domain(struct device_node *of_node,
struct msi_domain_info *info,
struct irq_domain *parent);
struct msi_domain_info *msi_get_domain_info(struct irq_domain *domain);
#endif /* CONFIG_GENERIC_MSI_IRQ_DOMAIN */
#endif /* LINUX_MSI_H */

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@ -60,6 +60,16 @@ config IRQ_DOMAIN_HIERARCHY
bool
select IRQ_DOMAIN
# Generic MSI interrupt support
config GENERIC_MSI_IRQ
bool
# Generic MSI hierarchical interrupt domain support
config GENERIC_MSI_IRQ_DOMAIN
bool
select IRQ_DOMAIN_HIERARCHY
select GENERIC_MSI_IRQ
config HANDLE_DOMAIN_IRQ
bool

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@ -6,3 +6,4 @@ obj-$(CONFIG_IRQ_DOMAIN) += irqdomain.o
obj-$(CONFIG_PROC_FS) += proc.o
obj-$(CONFIG_GENERIC_PENDING_IRQ) += migration.o
obj-$(CONFIG_PM_SLEEP) += pm.o
obj-$(CONFIG_GENERIC_MSI_IRQ) += msi.o

141
kernel/irq/msi.c Normal file
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@ -0,0 +1,141 @@
/*
* linux/kernel/irq/msi.c
*
* Copyright (C) 2014 Intel Corp.
* Author: Jiang Liu <jiang.liu@linux.intel.com>
*
* This file is licensed under GPLv2.
*
* This file contains common code to support Message Signalled Interrupt for
* PCI compatible and non PCI compatible devices.
*/
#include <linux/irq.h>
#include <linux/irqdomain.h>
#include <linux/msi.h>
#ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
/**
* msi_domain_set_affinity - Generic affinity setter function for MSI domains
* @irq_data: The irq data associated to the interrupt
* @mask: The affinity mask to set
* @force: Flag to enforce setting (disable online checks)
*
* Intended to be used by MSI interrupt controllers which are
* implemented with hierarchical domains.
*/
int msi_domain_set_affinity(struct irq_data *irq_data,
const struct cpumask *mask, bool force)
{
struct irq_data *parent = irq_data->parent_data;
struct msi_msg msg;
int ret;
ret = parent->chip->irq_set_affinity(parent, mask, force);
if (ret >= 0 && ret != IRQ_SET_MASK_OK_DONE) {
BUG_ON(irq_chip_compose_msi_msg(irq_data, &msg));
irq_chip_write_msi_msg(irq_data, &msg);
}
return ret;
}
static void msi_domain_activate(struct irq_domain *domain,
struct irq_data *irq_data)
{
struct msi_msg msg;
BUG_ON(irq_chip_compose_msi_msg(irq_data, &msg));
irq_chip_write_msi_msg(irq_data, &msg);
}
static void msi_domain_deactivate(struct irq_domain *domain,
struct irq_data *irq_data)
{
struct msi_msg msg;
memset(&msg, 0, sizeof(msg));
irq_chip_write_msi_msg(irq_data, &msg);
}
static int msi_domain_alloc(struct irq_domain *domain, unsigned int virq,
unsigned int nr_irqs, void *arg)
{
struct msi_domain_info *info = domain->host_data;
struct msi_domain_ops *ops = info->ops;
irq_hw_number_t hwirq = ops->get_hwirq(info, arg);
int i, ret;
if (irq_find_mapping(domain, hwirq) > 0)
return -EEXIST;
ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, arg);
if (ret < 0)
return ret;
for (i = 0; i < nr_irqs; i++) {
ret = ops->msi_init(domain, info, virq + i, hwirq + i, arg);
if (ret < 0) {
if (ops->msi_free) {
for (i--; i > 0; i--)
ops->msi_free(domain, info, virq + i);
}
irq_domain_free_irqs_top(domain, virq, nr_irqs);
return ret;
}
}
return 0;
}
static void msi_domain_free(struct irq_domain *domain, unsigned int virq,
unsigned int nr_irqs)
{
struct msi_domain_info *info = domain->host_data;
int i;
if (info->ops->msi_free) {
for (i = 0; i < nr_irqs; i++)
info->ops->msi_free(domain, info, virq + i);
}
irq_domain_free_irqs_top(domain, virq, nr_irqs);
}
static struct irq_domain_ops msi_domain_ops = {
.alloc = msi_domain_alloc,
.free = msi_domain_free,
.activate = msi_domain_activate,
.deactivate = msi_domain_deactivate,
};
/**
* msi_create_irq_domain - Create a MSI interrupt domain
* @of_node: Optional device-tree node of the interrupt controller
* @info: MSI domain info
* @parent: Parent irq domain
*/
struct irq_domain *msi_create_irq_domain(struct device_node *of_node,
struct msi_domain_info *info,
struct irq_domain *parent)
{
struct irq_domain *domain;
domain = irq_domain_add_tree(of_node, &msi_domain_ops, info);
if (domain)
domain->parent = parent;
return domain;
}
/**
* msi_get_domain_info - Get the MSI interrupt domain info for @domain
* @domain: The interrupt domain to retrieve data from
*
* Returns the pointer to the msi_domain_info stored in
* @domain->host_data.
*/
struct msi_domain_info *msi_get_domain_info(struct irq_domain *domain)
{
return (struct msi_domain_info *)domain->host_data;
}
#endif /* CONFIG_GENERIC_MSI_IRQ_DOMAIN */