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Commit f3cf8bb0 authored by Jiang Liu's avatar Jiang Liu Committed by Thomas Gleixner
Browse files

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: default avatarJiang 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: default avatarThomas Gleixner <tglx@linutronix.de>
parent 9dde55b7

include/linux/msi.h

+45 −0
Original line number Diff line number Diff line
@@ -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 */

kernel/irq/Kconfig

+10 −0
Original line number Diff line number Diff line
@@ -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

kernel/irq/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -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

kernel/irq/msi.c

0 → 100644
+141 −0
Original line number Diff line number Diff line 
/*

 * 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 */