[linux-block.git] / drivers / base / platform-msi.c

// SPDX-License-Identifier: GPL-2.0
/*
 * MSI framework for platform devices
 *
 * Copyright (C) 2015 ARM Limited, All Rights Reserved.
 * Author: Marc Zyngier <marc.zyngier@arm.com>
 * Copyright (C) 2022 Linutronix GmbH
 */

#include <linux/device.h>
#include <linux/irqdomain.h>
#include <linux/msi.h>

/*
 * This indirection can go when platform_device_msi_init_and_alloc_irqs()
 * is switched to a proper irq_chip::irq_write_msi_msg() callback. Keep it
 * simple for now.
 */
static void platform_msi_write_msi_msg(struct irq_data *d, struct msi_msg *msg)
{
	irq_write_msi_msg_t cb = d->chip_data;

	cb(irq_data_get_msi_desc(d), msg);
}

static void platform_msi_set_desc(msi_alloc_info_t *arg, struct msi_desc *desc)
{
	arg->desc = desc;
	arg->hwirq = desc->msi_index;
}

static const struct msi_domain_template platform_msi_template = {
	.chip = {
		.name			= "pMSI",
		.irq_mask		= irq_chip_mask_parent,
		.irq_unmask		= irq_chip_unmask_parent,
		.irq_write_msi_msg	= platform_msi_write_msi_msg,
		/* The rest is filled in by the platform MSI parent */
	},

	.ops = {
		.set_desc		= platform_msi_set_desc,
	},

	.info = {
		.bus_token		= DOMAIN_BUS_DEVICE_MSI,
	},
};

/**
 * platform_device_msi_init_and_alloc_irqs - Initialize platform device MSI
 *					     and allocate interrupts for @dev
 * @dev:		The device for which to allocate interrupts
 * @nvec:		The number of interrupts to allocate
 * @write_msi_msg:	Callback to write an interrupt message for @dev
 *
 * Returns:
 * Zero for success, or an error code in case of failure
 *
 * This creates a MSI domain on @dev which has @dev->msi.domain as
 * parent. The parent domain sets up the new domain. The domain has
 * a fixed size of @nvec. The domain is managed by devres and will
 * be removed when the device is removed.
 *
 * Note: For migration purposes this falls back to the original platform_msi code
 *	 up to the point where all platforms have been converted to the MSI
 *	 parent model.
 */
int platform_device_msi_init_and_alloc_irqs(struct device *dev, unsigned int nvec,
					    irq_write_msi_msg_t write_msi_msg)
{
	struct irq_domain *domain = dev->msi.domain;

	if (!domain || !write_msi_msg)
		return -EINVAL;

	/*
	 * @write_msi_msg is stored in the resulting msi_domain_info::data.
	 * The underlying domain creation mechanism will assign that
	 * callback to the resulting irq chip.
	 */
	if (!msi_create_device_irq_domain(dev, MSI_DEFAULT_DOMAIN,
					  &platform_msi_template,
					  nvec, NULL, write_msi_msg))
		return -ENODEV;

	return msi_domain_alloc_irqs_range(dev, MSI_DEFAULT_DOMAIN, 0, nvec - 1);
}
EXPORT_SYMBOL_GPL(platform_device_msi_init_and_alloc_irqs);

/**
 * platform_device_msi_free_irqs_all - Free all interrupts for @dev
 * @dev:	The device for which to free interrupts
 */
void platform_device_msi_free_irqs_all(struct device *dev)
{
	msi_domain_free_irqs_all(dev, MSI_DEFAULT_DOMAIN);
}
EXPORT_SYMBOL_GPL(platform_device_msi_free_irqs_all);
Commit	Line	Data
989d42e8	1	// SPDX-License-Identifier: GPL-2.0
c09fcc4b MZ	2	/*
	3	* MSI framework for platform devices
	4	*
	5	* Copyright (C) 2015 ARM Limited, All Rights Reserved.
	6	* Author: Marc Zyngier <marc.zyngier@arm.com>
e9894248	7	* Copyright (C) 2022 Linutronix GmbH
c09fcc4b MZ	8	*/
	9
	10	#include <linux/device.h>
c09fcc4b MZ	11	#include <linux/irqdomain.h>
c09fcc4b MZ	12	#include <linux/msi.h>
c88f9110 TG	13
	14	/*
	15	* This indirection can go when platform_device_msi_init_and_alloc_irqs()
	16	* is switched to a proper irq_chip::irq_write_msi_msg() callback. Keep it
	17	* simple for now.
	18	*/
	19	static void platform_msi_write_msi_msg(struct irq_data d, struct msi_msg msg)
	20	{
	21	irq_write_msi_msg_t cb = d->chip_data;
	22
	23	cb(irq_data_get_msi_desc(d), msg);
	24	}
	25
e9894248	26	static void platform_msi_set_desc(msi_alloc_info_t arg, struct msi_desc desc)
c88f9110 TG	27	{
	28	arg->desc = desc;
	29	arg->hwirq = desc->msi_index;
	30	}
	31
	32	static const struct msi_domain_template platform_msi_template = {
	33	.chip = {
	34	.name = "pMSI",
	35	.irq_mask = irq_chip_mask_parent,
	36	.irq_unmask = irq_chip_unmask_parent,
	37	.irq_write_msi_msg = platform_msi_write_msi_msg,
	38	/* The rest is filled in by the platform MSI parent */
	39	},
	40
	41	.ops = {
e9894248	42	.set_desc = platform_msi_set_desc,
c88f9110 TG	43	},
	44
	45	.info = {
	46	.bus_token = DOMAIN_BUS_DEVICE_MSI,
	47	},
	48	};
	49
	50	/**
	51	* platform_device_msi_init_and_alloc_irqs - Initialize platform device MSI
	52	* and allocate interrupts for @dev
	53	* @dev: The device for which to allocate interrupts
	54	* @nvec: The number of interrupts to allocate
	55	* @write_msi_msg: Callback to write an interrupt message for @dev
	56	*
	57	* Returns:
	58	* Zero for success, or an error code in case of failure
	59	*
	60	* This creates a MSI domain on @dev which has @dev->msi.domain as
	61	* parent. The parent domain sets up the new domain. The domain has
	62	* a fixed size of @nvec. The domain is managed by devres and will
	63	* be removed when the device is removed.
	64	*
	65	* Note: For migration purposes this falls back to the original platform_msi code
	66	* up to the point where all platforms have been converted to the MSI
	67	* parent model.
	68	*/
	69	int platform_device_msi_init_and_alloc_irqs(struct device *dev, unsigned int nvec,
	70	irq_write_msi_msg_t write_msi_msg)
	71	{
	72	struct irq_domain *domain = dev->msi.domain;
	73
	74	if (!domain \|\| !write_msi_msg)
	75	return -EINVAL;
	76
c88f9110 TG	77	/*
	78	* @write_msi_msg is stored in the resulting msi_domain_info::data.
	79	* The underlying domain creation mechanism will assign that
	80	* callback to the resulting irq chip.
	81	*/
	82	if (!msi_create_device_irq_domain(dev, MSI_DEFAULT_DOMAIN,
	83	&platform_msi_template,
	84	nvec, NULL, write_msi_msg))
	85	return -ENODEV;
	86
	87	return msi_domain_alloc_irqs_range(dev, MSI_DEFAULT_DOMAIN, 0, nvec - 1);
	88	}
	89	EXPORT_SYMBOL_GPL(platform_device_msi_init_and_alloc_irqs);
	90
	91	/**
	92	* platform_device_msi_free_irqs_all - Free all interrupts for @dev
	93	* @dev: The device for which to free interrupts
	94	*/
	95	void platform_device_msi_free_irqs_all(struct device *dev)
	96	{
c88f9110	97	msi_domain_free_irqs_all(dev, MSI_DEFAULT_DOMAIN);
c88f9110 TG	98	}
c88f9110 TG	99	EXPORT_SYMBOL_GPL(platform_device_msi_free_irqs_all);