Commit d9109698 authored by Jiang Liu's avatar Jiang Liu Committed by Thomas Gleixner
Browse files

genirq: Introduce msi_domain_alloc/free_irqs() 



Introduce msi_domain_{alloc|free}_irqs() to alloc/free interrupts
from generic MSI irqdomain.

Signed-off-by: default avatarJiang Liu <jiang.liu@linux.intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Yijing Wang <wangyijing@huawei.com>
Cc: Yingjoe Chen <yingjoe.chen@mediatek.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Alexander Gordeev <agordeev@redhat.com>
Link: http://lkml.kernel.org/r/1416061447-9472-7-git-send-email-jiang.liu@linux.intel.com


Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
parent 926ff9ad

include/linux/msi.h

+29 −0
Original line number Diff line number Diff line
@@ -115,6 +115,9 @@ struct msi_controller { 
};



#ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN



#include <asm/msi.h>



struct irq_domain;

struct irq_chip;

struct device_node;
@@ -125,6 +128,18 @@ struct msi_domain_info; 
 * @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

 * @msi_check:		Callback for verification of the domain/info/dev data

 * @msi_prepare:	Prepare the allocation of the interrupts in the domain

 * @msi_finish:		Optional callbacl to finalize the allocation

 * @set_desc:		Set the msi descriptor for an interrupt

 * @handle_error:	Optional error handler if the allocation fails

 *

 * @get_hwirq, @msi_init and @msi_free are callbacks used by

 * msi_create_irq_domain() and related interfaces

 *

 * @msi_check, @msi_prepare, @msi_finish, @set_desc and @handle_error

 * are callbacks used by msi_irq_domain_alloc_irqs() and related

 * interfaces which are based on msi_desc.

 */

struct msi_domain_ops {

	irq_hw_number_t	(*get_hwirq)(struct msi_domain_info *info, void *arg);
@@ -135,6 +150,17 @@ struct msi_domain_ops { 
	void		(*msi_free)(struct irq_domain *domain,

				    struct msi_domain_info *info,

				    unsigned int virq);

	int		(*msi_check)(struct irq_domain *domain,

				     struct msi_domain_info *info,

				     struct device *dev);

	int		(*msi_prepare)(struct irq_domain *domain,

				       struct device *dev, int nvec,

				       msi_alloc_info_t *arg);

	void		(*msi_finish)(msi_alloc_info_t *arg, int retval);

	void		(*set_desc)(msi_alloc_info_t *arg,

				    struct msi_desc *desc);

	int		(*handle_error)(struct irq_domain *domain,

					struct msi_desc *desc, int error);

};



/**
@@ -155,6 +181,9 @@ int msi_domain_set_affinity(struct irq_data *data, const struct cpumask *mask, 
struct irq_domain *msi_create_irq_domain(struct device_node *of_node,

					 struct msi_domain_info *info,

					 struct irq_domain *parent);

int msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev,

			  int nvec);

void msi_domain_free_irqs(struct irq_domain *domain, struct device *dev);

struct msi_domain_info *msi_get_domain_info(struct irq_domain *domain);



#endif /* CONFIG_GENERIC_MSI_IRQ_DOMAIN */

kernel/irq/msi.c

+75 −0
Original line number Diff line number Diff line
@@ -13,6 +13,9 @@ 
#include <linux/irqdomain.h>

#include <linux/msi.h>



/* Temparory solution for building, will be removed later */

#include <linux/pci.h>



#ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN

/**

 * msi_domain_set_affinity - Generic affinity setter function for MSI domains
@@ -126,6 +129,78 @@ struct irq_domain *msi_create_irq_domain(struct device_node *of_node, 
	return domain;

}



/**

 * msi_domain_alloc_irqs - Allocate interrupts from a MSI interrupt domain

 * @domain:	The domain to allocate from

 * @dev:	Pointer to device struct of the device for which the interrupts

 *		are allocated

 * @nvec:	The number of interrupts to allocate

 *

 * Returns 0 on success or an error code.

 */

int msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev,

			  int nvec)

{

	struct msi_domain_info *info = domain->host_data;

	struct msi_domain_ops *ops = info->ops;

	msi_alloc_info_t arg;

	struct msi_desc *desc;

	int i, ret, virq = -1;



	ret = ops->msi_check(domain, info, dev);

	if (ret == 0)

		ret = ops->msi_prepare(domain, dev, nvec, &arg);

	if (ret)

		return ret;



	for_each_msi_entry(desc, dev) {

		ops->set_desc(&arg, desc);



		virq = __irq_domain_alloc_irqs(domain, -1, desc->nvec_used,

					       dev_to_node(dev), &arg, false);

		if (virq < 0) {

			ret = -ENOSPC;

			if (ops->handle_error)

				ret = ops->handle_error(domain, desc, ret);

			if (ops->msi_finish)

				ops->msi_finish(&arg, ret);

			return ret;

		}



		for (i = 0; i < desc->nvec_used; i++)

			irq_set_msi_desc_off(virq, i, desc);

	}



	if (ops->msi_finish)

		ops->msi_finish(&arg, 0);



	for_each_msi_entry(desc, dev) {

		if (desc->nvec_used == 1)

			dev_dbg(dev, "irq %d for MSI\n", virq);

		else

			dev_dbg(dev, "irq [%d-%d] for MSI\n",

				virq, virq + desc->nvec_used - 1);

	}



	return 0;

}



/**

 * msi_domain_free_irqs - Free interrupts from a MSI interrupt @domain associated tp @dev

 * @domain:	The domain to managing the interrupts

 * @dev:	Pointer to device struct of the device for which the interrupts

 *		are free

 */

void msi_domain_free_irqs(struct irq_domain *domain, struct device *dev)

{

	struct msi_desc *desc;



	for_each_msi_entry(desc, dev) {

		irq_domain_free_irqs(desc->irq, desc->nvec_used);

		desc->irq = 0;

	}

}



/**

 * msi_get_domain_info - Get the MSI interrupt domain info for @domain

 * @domain:	The interrupt domain to retrieve data from

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