drivers/irqchip/irq-ls-scfg-msi.c - linux - Git at Google

 /*
  * Freescale SCFG MSI(-X) support
  *
  * Copyright (C) 2016 Freescale Semiconductor.
  *
  * Author: Minghuan Lian <Minghuan.Lian@nxp.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/kernel.h>
 #include <linux/module.h>
 #include <linux/msi.h>
 #include <linux/interrupt.h>
 #include <linux/irq.h>
 #include <linux/irqchip/chained_irq.h>
 #include <linux/irqdomain.h>
 #include <linux/of_irq.h>
 #include <linux/of_pci.h>
 #include <linux/of_platform.h>
 #include <linux/spinlock.h>
 #include <linux/dma-iommu.h>

 #define MSI_IRQS_PER_MSIR	32
 #define MSI_MSIR_OFFSET		4

 #define MSI_LS1043V1_1_IRQS_PER_MSIR	8
 #define MSI_LS1043V1_1_MSIR_OFFSET	0x10

 struct ls_scfg_msi_cfg {
 	u32 ibs_shift; /* Shift of interrupt bit select */
 	u32 msir_irqs; /* The irq number per MSIR */
 	u32 msir_base; /* The base address of MSIR */
 };

 struct ls_scfg_msir {
 	struct ls_scfg_msi *msi_data;
 	unsigned int index;
 	unsigned int gic_irq;
 	unsigned int bit_start;
 	unsigned int bit_end;
 	unsigned int srs; /* Shared interrupt register select */
 	void __iomem *reg;
 };

 struct ls_scfg_msi {
 	spinlock_t		lock;
 	struct platform_device	*pdev;
 	struct irq_domain	*parent;
 	struct irq_domain	*msi_domain;
 	void __iomem		*regs;
 	phys_addr_t		msiir_addr;
 	struct ls_scfg_msi_cfg	*cfg;
 	u32			msir_num;
 	struct ls_scfg_msir	*msir;
 	u32			irqs_num;
 	unsigned long		*used;
 };

 static struct irq_chip ls_scfg_msi_irq_chip = {
 	.name = "MSI",
 	.irq_mask	= pci_msi_mask_irq,
 	.irq_unmask	= pci_msi_unmask_irq,
 };

 static struct msi_domain_info ls_scfg_msi_domain_info = {
 	.flags	= (MSI_FLAG_USE_DEF_DOM_OPS |
 		   MSI_FLAG_USE_DEF_CHIP_OPS |
 		   MSI_FLAG_PCI_MSIX),
 	.chip	= &ls_scfg_msi_irq_chip,
 };

 static int msi_affinity_flag = 1;

 static int __init early_parse_ls_scfg_msi(char *p)
 {
 	if (p && strncmp(p, "no-affinity", 11) == 0)
 		msi_affinity_flag = 0;
 	else
 		msi_affinity_flag = 1;

 	return 0;
 }
 early_param("lsmsi", early_parse_ls_scfg_msi);

 static void ls_scfg_msi_compose_msg(struct irq_data *data, struct msi_msg *msg)
 {
 	struct ls_scfg_msi *msi_data = irq_data_get_irq_chip_data(data);

 	msg->address_hi = upper_32_bits(msi_data->msiir_addr);
 	msg->address_lo = lower_32_bits(msi_data->msiir_addr);
 	msg->data = data->hwirq;

 	if (msi_affinity_flag)
 		msg->data |= cpumask_first(data->common->affinity);

 	iommu_dma_map_msi_msg(data->irq, msg);
 }

 static int ls_scfg_msi_set_affinity(struct irq_data *irq_data,
 				    const struct cpumask *mask, bool force)
 {
 	struct ls_scfg_msi *msi_data = irq_data_get_irq_chip_data(irq_data);
 	u32 cpu;

 	if (!msi_affinity_flag)
 		return -EINVAL;

 	if (!force)
 		cpu = cpumask_any_and(mask, cpu_online_mask);
 	else
 		cpu = cpumask_first(mask);

 	if (cpu >= msi_data->msir_num)
 		return -EINVAL;

 	if (msi_data->msir[cpu].gic_irq <= 0) {
 		pr_warn("cannot bind the irq to cpu%d\n", cpu);
 		return -EINVAL;
 	}

 	cpumask_copy(irq_data->common->affinity, mask);

 	return IRQ_SET_MASK_OK;
 }

 static struct irq_chip ls_scfg_msi_parent_chip = {
 	.name			= "SCFG",
 	.irq_compose_msi_msg	= ls_scfg_msi_compose_msg,
 	.irq_set_affinity	= ls_scfg_msi_set_affinity,
 };

 static int ls_scfg_msi_domain_irq_alloc(struct irq_domain *domain,
 					unsigned int virq,
 					unsigned int nr_irqs,
 					void *args)
 {
 	struct ls_scfg_msi *msi_data = domain->host_data;
 	int pos, err = 0;

 	WARN_ON(nr_irqs != 1);

 	spin_lock(&msi_data->lock);
 	pos = find_first_zero_bit(msi_data->used, msi_data->irqs_num);
 	if (pos < msi_data->irqs_num)
 		__set_bit(pos, msi_data->used);
 	else
 		err = -ENOSPC;
 	spin_unlock(&msi_data->lock);

 	if (err)
 		return err;

 	irq_domain_set_info(domain, virq, pos,
 			    &ls_scfg_msi_parent_chip, msi_data,
 			    handle_simple_irq, NULL, NULL);

 	return 0;
 }

 static void ls_scfg_msi_domain_irq_free(struct irq_domain *domain,
 				   unsigned int virq, unsigned int nr_irqs)
 {
 	struct irq_data *d = irq_domain_get_irq_data(domain, virq);
 	struct ls_scfg_msi *msi_data = irq_data_get_irq_chip_data(d);
 	int pos;

 	pos = d->hwirq;
 	if (pos < 0 || pos >= msi_data->irqs_num) {
 		pr_err("failed to teardown msi. Invalid hwirq %d\n", pos);
 		return;
 	}

 	spin_lock(&msi_data->lock);
 	__clear_bit(pos, msi_data->used);
 	spin_unlock(&msi_data->lock);
 }

 static const struct irq_domain_ops ls_scfg_msi_domain_ops = {
 	.alloc	= ls_scfg_msi_domain_irq_alloc,
 	.free	= ls_scfg_msi_domain_irq_free,
 };

 static void ls_scfg_msi_irq_handler(struct irq_desc *desc)
 {
 	struct ls_scfg_msir *msir = irq_desc_get_handler_data(desc);
 	struct ls_scfg_msi *msi_data = msir->msi_data;
 	unsigned long val;
 	int pos, size, virq, hwirq;

 	chained_irq_enter(irq_desc_get_chip(desc), desc);

 	val = ioread32be(msir->reg);

 	pos = msir->bit_start;
 	size = msir->bit_end + 1;

 	for_each_set_bit_from(pos, &val, size) {
 		hwirq = ((msir->bit_end - pos) << msi_data->cfg->ibs_shift) |
 			msir->srs;
 		virq = irq_find_mapping(msi_data->parent, hwirq);
 		if (virq)
 			generic_handle_irq(virq);
 	}

 	chained_irq_exit(irq_desc_get_chip(desc), desc);
 }

 static int ls_scfg_msi_domains_init(struct ls_scfg_msi *msi_data)
 {
 	/* Initialize MSI domain parent */
 	msi_data->parent = irq_domain_add_linear(NULL,
 						 msi_data->irqs_num,
 						 &ls_scfg_msi_domain_ops,
 						 msi_data);
 	if (!msi_data->parent) {
 		dev_err(&msi_data->pdev->dev, "failed to create IRQ domain\n");
 		return -ENOMEM;
 	}

 	msi_data->msi_domain = pci_msi_create_irq_domain(
 				of_node_to_fwnode(msi_data->pdev->dev.of_node),
 				&ls_scfg_msi_domain_info,
 				msi_data->parent);
 	if (!msi_data->msi_domain) {
 		dev_err(&msi_data->pdev->dev, "failed to create MSI domain\n");
 		irq_domain_remove(msi_data->parent);
 		return -ENOMEM;
 	}

 	return 0;
 }

 static int ls_scfg_msi_setup_hwirq(struct ls_scfg_msi *msi_data, int index)
 {
 	struct ls_scfg_msir *msir;
 	int virq, i, hwirq;

 	virq = platform_get_irq(msi_data->pdev, index);
 	if (virq <= 0)
 		return -ENODEV;

 	msir = &msi_data->msir[index];
 	msir->index = index;
 	msir->msi_data = msi_data;
 	msir->gic_irq = virq;
 	msir->reg = msi_data->regs + msi_data->cfg->msir_base + 4 * index;

 	if (msi_data->cfg->msir_irqs == MSI_LS1043V1_1_IRQS_PER_MSIR) {
 		msir->bit_start = 32 - ((msir->index + 1) *
 				  MSI_LS1043V1_1_IRQS_PER_MSIR);
 		msir->bit_end = msir->bit_start +
 				MSI_LS1043V1_1_IRQS_PER_MSIR - 1;
 	} else {
 		msir->bit_start = 0;
 		msir->bit_end = msi_data->cfg->msir_irqs - 1;
 	}

 	irq_set_chained_handler_and_data(msir->gic_irq,
 					 ls_scfg_msi_irq_handler,
 					 msir);

 	if (msi_affinity_flag) {
 		/* Associate MSIR interrupt to the cpu */
 		irq_set_affinity(msir->gic_irq, get_cpu_mask(index));
 		msir->srs = 0; /* This value is determined by the CPU */
 	} else
 		msir->srs = index;

 	/* Release the hwirqs corresponding to this MSIR */
 	if (!msi_affinity_flag || msir->index == 0) {
 		for (i = 0; i < msi_data->cfg->msir_irqs; i++) {
 			hwirq = i << msi_data->cfg->ibs_shift | msir->index;
 			bitmap_clear(msi_data->used, hwirq, 1);
 		}
 	}

 	return 0;
 }

 static int ls_scfg_msi_teardown_hwirq(struct ls_scfg_msir *msir)
 {
 	struct ls_scfg_msi *msi_data = msir->msi_data;
 	int i, hwirq;

 	if (msir->gic_irq > 0)
 		irq_set_chained_handler_and_data(msir->gic_irq, NULL, NULL);

 	for (i = 0; i < msi_data->cfg->msir_irqs; i++) {
 		hwirq = i << msi_data->cfg->ibs_shift | msir->index;
 		bitmap_set(msi_data->used, hwirq, 1);
 	}

 	return 0;
 }

 static struct ls_scfg_msi_cfg ls1021_msi_cfg = {
 	.ibs_shift = 3,
 	.msir_irqs = MSI_IRQS_PER_MSIR,
 	.msir_base = MSI_MSIR_OFFSET,
 };

 static struct ls_scfg_msi_cfg ls1046_msi_cfg = {
 	.ibs_shift = 2,
 	.msir_irqs = MSI_IRQS_PER_MSIR,
 	.msir_base = MSI_MSIR_OFFSET,
 };

 static struct ls_scfg_msi_cfg ls1043_v1_1_msi_cfg = {
 	.ibs_shift = 2,
 	.msir_irqs = MSI_LS1043V1_1_IRQS_PER_MSIR,
 	.msir_base = MSI_LS1043V1_1_MSIR_OFFSET,
 };

 static const struct of_device_id ls_scfg_msi_id[] = {
 	/* The following two misspelled compatibles are obsolete */
 	{ .compatible = "fsl,1s1021a-msi", .data = &ls1021_msi_cfg},
 	{ .compatible = "fsl,1s1043a-msi", .data = &ls1021_msi_cfg},

 	{ .compatible = "fsl,ls1012a-msi", .data = &ls1021_msi_cfg },
 	{ .compatible = "fsl,ls1021a-msi", .data = &ls1021_msi_cfg },
 	{ .compatible = "fsl,ls1043a-msi", .data = &ls1021_msi_cfg },
 	{ .compatible = "fsl,ls1043a-v1.1-msi", .data = &ls1043_v1_1_msi_cfg },
 	{ .compatible = "fsl,ls1046a-msi", .data = &ls1046_msi_cfg },
 	{},
 };
 MODULE_DEVICE_TABLE(of, ls_scfg_msi_id);

 static int ls_scfg_msi_probe(struct platform_device *pdev)
 {
 	const struct of_device_id *match;
 	struct ls_scfg_msi *msi_data;
 	struct resource *res;
 	int i, ret;

 	match = of_match_device(ls_scfg_msi_id, &pdev->dev);
 	if (!match)
 		return -ENODEV;

 	msi_data = devm_kzalloc(&pdev->dev, sizeof(*msi_data), GFP_KERNEL);
 	if (!msi_data)
 		return -ENOMEM;

 	msi_data->cfg = (struct ls_scfg_msi_cfg *) match->data;

 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	msi_data->regs = devm_ioremap_resource(&pdev->dev, res);
 	if (IS_ERR(msi_data->regs)) {
 		dev_err(&pdev->dev, "failed to initialize 'regs'\n");
 		return PTR_ERR(msi_data->regs);
 	}
 	msi_data->msiir_addr = res->start;

 	msi_data->pdev = pdev;
 	spin_lock_init(&msi_data->lock);

 	msi_data->irqs_num = MSI_IRQS_PER_MSIR *
 			     (1 << msi_data->cfg->ibs_shift);
 	msi_data->used = devm_kcalloc(&pdev->dev,
 				    BITS_TO_LONGS(msi_data->irqs_num),
 				    sizeof(*msi_data->used),
 				    GFP_KERNEL);
 	if (!msi_data->used)
 		return -ENOMEM;
 	/*
 	 * Reserve all the hwirqs
 	 * The available hwirqs will be released in ls1_msi_setup_hwirq()
 	 */
 	bitmap_set(msi_data->used, 0, msi_data->irqs_num);

 	msi_data->msir_num = of_irq_count(pdev->dev.of_node);

 	if (msi_affinity_flag) {
 		u32 cpu_num;

 		cpu_num = num_possible_cpus();
 		if (msi_data->msir_num >= cpu_num)
 			msi_data->msir_num = cpu_num;
 		else
 			msi_affinity_flag = 0;
 	}

 	msi_data->msir = devm_kcalloc(&pdev->dev, msi_data->msir_num,
 				      sizeof(*msi_data->msir),
 				      GFP_KERNEL);
 	if (!msi_data->msir)
 		return -ENOMEM;

 	for (i = 0; i < msi_data->msir_num; i++)
 		ls_scfg_msi_setup_hwirq(msi_data, i);

 	ret = ls_scfg_msi_domains_init(msi_data);
 	if (ret)
 		return ret;

 	platform_set_drvdata(pdev, msi_data);

 	return 0;
 }

 static int ls_scfg_msi_remove(struct platform_device *pdev)
 {
 	struct ls_scfg_msi *msi_data = platform_get_drvdata(pdev);
 	int i;

 	for (i = 0; i < msi_data->msir_num; i++)
 		ls_scfg_msi_teardown_hwirq(&msi_data->msir[i]);

 	irq_domain_remove(msi_data->msi_domain);
 	irq_domain_remove(msi_data->parent);

 	platform_set_drvdata(pdev, NULL);

 	return 0;
 }

 static struct platform_driver ls_scfg_msi_driver = {
 	.driver = {
 		.name = "ls-scfg-msi",
 		.of_match_table = ls_scfg_msi_id,
 	},
 	.probe = ls_scfg_msi_probe,
 	.remove = ls_scfg_msi_remove,
 };

 module_platform_driver(ls_scfg_msi_driver);

 MODULE_AUTHOR("Minghuan Lian <Minghuan.Lian@nxp.com>");
 MODULE_DESCRIPTION("Freescale Layerscape SCFG MSI controller driver");
 MODULE_LICENSE("GPL v2");
	/*
	* Freescale SCFG MSI(-X) support
	*
	* Copyright (C) 2016 Freescale Semiconductor.
	*
	* Author: Minghuan Lian <Minghuan.Lian@nxp.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/kernel.h>
	#include <linux/module.h>
	#include <linux/msi.h>
	#include <linux/interrupt.h>
	#include <linux/irq.h>
	#include <linux/irqchip/chained_irq.h>
	#include <linux/irqdomain.h>
	#include <linux/of_irq.h>
	#include <linux/of_pci.h>
	#include <linux/of_platform.h>
	#include <linux/spinlock.h>
	#include <linux/dma-iommu.h>

	#define MSI_IRQS_PER_MSIR 32
	#define MSI_MSIR_OFFSET 4

	#define MSI_LS1043V1_1_IRQS_PER_MSIR 8
	#define MSI_LS1043V1_1_MSIR_OFFSET 0x10

	struct ls_scfg_msi_cfg {
	u32 ibs_shift; /* Shift of interrupt bit select */
	u32 msir_irqs; /* The irq number per MSIR */
	u32 msir_base; /* The base address of MSIR */
	};

	struct ls_scfg_msir {
	struct ls_scfg_msi *msi_data;
	unsigned int index;
	unsigned int gic_irq;
	unsigned int bit_start;
	unsigned int bit_end;
	unsigned int srs; /* Shared interrupt register select */
	void __iomem *reg;
	};

	struct ls_scfg_msi {
	spinlock_t lock;
	struct platform_device *pdev;
	struct irq_domain *parent;
	struct irq_domain *msi_domain;
	void __iomem *regs;
	phys_addr_t msiir_addr;
	struct ls_scfg_msi_cfg *cfg;
	u32 msir_num;
	struct ls_scfg_msir *msir;
	u32 irqs_num;
	unsigned long *used;
	};

	static struct irq_chip ls_scfg_msi_irq_chip = {
	.name = "MSI",
	.irq_mask = pci_msi_mask_irq,
	.irq_unmask = pci_msi_unmask_irq,
	};

	static struct msi_domain_info ls_scfg_msi_domain_info = {
	.flags = (MSI_FLAG_USE_DEF_DOM_OPS \|
	MSI_FLAG_USE_DEF_CHIP_OPS \|
	MSI_FLAG_PCI_MSIX),
	.chip = &ls_scfg_msi_irq_chip,
	};

	static int msi_affinity_flag = 1;

	static int __init early_parse_ls_scfg_msi(char *p)
	{
	if (p && strncmp(p, "no-affinity", 11) == 0)
	msi_affinity_flag = 0;
	else
	msi_affinity_flag = 1;

	return 0;
	}
	early_param("lsmsi", early_parse_ls_scfg_msi);

	static void ls_scfg_msi_compose_msg(struct irq_data data, struct msi_msg msg)
	{
	struct ls_scfg_msi *msi_data = irq_data_get_irq_chip_data(data);

	msg->address_hi = upper_32_bits(msi_data->msiir_addr);
	msg->address_lo = lower_32_bits(msi_data->msiir_addr);
	msg->data = data->hwirq;

	if (msi_affinity_flag)
	msg->data \|= cpumask_first(data->common->affinity);

	iommu_dma_map_msi_msg(data->irq, msg);
	}

	static int ls_scfg_msi_set_affinity(struct irq_data *irq_data,
	const struct cpumask *mask, bool force)
	{
	struct ls_scfg_msi *msi_data = irq_data_get_irq_chip_data(irq_data);
	u32 cpu;

	if (!msi_affinity_flag)
	return -EINVAL;

	if (!force)
	cpu = cpumask_any_and(mask, cpu_online_mask);
	else
	cpu = cpumask_first(mask);

	if (cpu >= msi_data->msir_num)
	return -EINVAL;

	if (msi_data->msir[cpu].gic_irq <= 0) {
	pr_warn("cannot bind the irq to cpu%d\n", cpu);
	return -EINVAL;
	}

	cpumask_copy(irq_data->common->affinity, mask);

	return IRQ_SET_MASK_OK;
	}

	static struct irq_chip ls_scfg_msi_parent_chip = {
	.name = "SCFG",
	.irq_compose_msi_msg = ls_scfg_msi_compose_msg,
	.irq_set_affinity = ls_scfg_msi_set_affinity,
	};

	static int ls_scfg_msi_domain_irq_alloc(struct irq_domain *domain,
	unsigned int virq,
	unsigned int nr_irqs,
	void *args)
	{
	struct ls_scfg_msi *msi_data = domain->host_data;
	int pos, err = 0;

	WARN_ON(nr_irqs != 1);

	spin_lock(&msi_data->lock);
	pos = find_first_zero_bit(msi_data->used, msi_data->irqs_num);
	if (pos < msi_data->irqs_num)
	__set_bit(pos, msi_data->used);
	else
	err = -ENOSPC;
	spin_unlock(&msi_data->lock);

	if (err)
	return err;

	irq_domain_set_info(domain, virq, pos,
	&ls_scfg_msi_parent_chip, msi_data,
	handle_simple_irq, NULL, NULL);

	return 0;
	}

	static void ls_scfg_msi_domain_irq_free(struct irq_domain *domain,
	unsigned int virq, unsigned int nr_irqs)
	{
	struct irq_data *d = irq_domain_get_irq_data(domain, virq);
	struct ls_scfg_msi *msi_data = irq_data_get_irq_chip_data(d);
	int pos;

	pos = d->hwirq;
	if (pos < 0 \|\| pos >= msi_data->irqs_num) {
	pr_err("failed to teardown msi. Invalid hwirq %d\n", pos);
	return;
	}

	spin_lock(&msi_data->lock);
	__clear_bit(pos, msi_data->used);
	spin_unlock(&msi_data->lock);
	}

	static const struct irq_domain_ops ls_scfg_msi_domain_ops = {
	.alloc = ls_scfg_msi_domain_irq_alloc,
	.free = ls_scfg_msi_domain_irq_free,
	};

	static void ls_scfg_msi_irq_handler(struct irq_desc *desc)
	{
	struct ls_scfg_msir *msir = irq_desc_get_handler_data(desc);
	struct ls_scfg_msi *msi_data = msir->msi_data;
	unsigned long val;
	int pos, size, virq, hwirq;

	chained_irq_enter(irq_desc_get_chip(desc), desc);

	val = ioread32be(msir->reg);

	pos = msir->bit_start;
	size = msir->bit_end + 1;

	for_each_set_bit_from(pos, &val, size) {
	hwirq = ((msir->bit_end - pos) << msi_data->cfg->ibs_shift) \|
	msir->srs;
	virq = irq_find_mapping(msi_data->parent, hwirq);
	if (virq)
	generic_handle_irq(virq);
	}

	chained_irq_exit(irq_desc_get_chip(desc), desc);
	}

	static int ls_scfg_msi_domains_init(struct ls_scfg_msi *msi_data)
	{
	/* Initialize MSI domain parent */
	msi_data->parent = irq_domain_add_linear(NULL,
	msi_data->irqs_num,
	&ls_scfg_msi_domain_ops,
	msi_data);
	if (!msi_data->parent) {
	dev_err(&msi_data->pdev->dev, "failed to create IRQ domain\n");
	return -ENOMEM;
	}

	msi_data->msi_domain = pci_msi_create_irq_domain(
	of_node_to_fwnode(msi_data->pdev->dev.of_node),
	&ls_scfg_msi_domain_info,
	msi_data->parent);
	if (!msi_data->msi_domain) {
	dev_err(&msi_data->pdev->dev, "failed to create MSI domain\n");
	irq_domain_remove(msi_data->parent);
	return -ENOMEM;
	}

	return 0;
	}

	static int ls_scfg_msi_setup_hwirq(struct ls_scfg_msi *msi_data, int index)
	{
	struct ls_scfg_msir *msir;
	int virq, i, hwirq;

	virq = platform_get_irq(msi_data->pdev, index);
	if (virq <= 0)
	return -ENODEV;

	msir = &msi_data->msir[index];
	msir->index = index;
	msir->msi_data = msi_data;
	msir->gic_irq = virq;
	msir->reg = msi_data->regs + msi_data->cfg->msir_base + 4 * index;

	if (msi_data->cfg->msir_irqs == MSI_LS1043V1_1_IRQS_PER_MSIR) {
	msir->bit_start = 32 - ((msir->index + 1) *
	MSI_LS1043V1_1_IRQS_PER_MSIR);
	msir->bit_end = msir->bit_start +
	MSI_LS1043V1_1_IRQS_PER_MSIR - 1;
	} else {
	msir->bit_start = 0;
	msir->bit_end = msi_data->cfg->msir_irqs - 1;
	}

	irq_set_chained_handler_and_data(msir->gic_irq,
	ls_scfg_msi_irq_handler,
	msir);

	if (msi_affinity_flag) {
	/* Associate MSIR interrupt to the cpu */
	irq_set_affinity(msir->gic_irq, get_cpu_mask(index));
	msir->srs = 0; /* This value is determined by the CPU */
	} else
	msir->srs = index;

	/* Release the hwirqs corresponding to this MSIR */
	if (!msi_affinity_flag \|\| msir->index == 0) {
	for (i = 0; i < msi_data->cfg->msir_irqs; i++) {
	hwirq = i << msi_data->cfg->ibs_shift \| msir->index;
	bitmap_clear(msi_data->used, hwirq, 1);
	}
	}

	return 0;
	}

	static int ls_scfg_msi_teardown_hwirq(struct ls_scfg_msir *msir)
	{
	struct ls_scfg_msi *msi_data = msir->msi_data;
	int i, hwirq;

	if (msir->gic_irq > 0)
	irq_set_chained_handler_and_data(msir->gic_irq, NULL, NULL);

	for (i = 0; i < msi_data->cfg->msir_irqs; i++) {
	hwirq = i << msi_data->cfg->ibs_shift \| msir->index;
	bitmap_set(msi_data->used, hwirq, 1);
	}

	return 0;
	}

	static struct ls_scfg_msi_cfg ls1021_msi_cfg = {
	.ibs_shift = 3,
	.msir_irqs = MSI_IRQS_PER_MSIR,
	.msir_base = MSI_MSIR_OFFSET,
	};

	static struct ls_scfg_msi_cfg ls1046_msi_cfg = {
	.ibs_shift = 2,
	.msir_irqs = MSI_IRQS_PER_MSIR,
	.msir_base = MSI_MSIR_OFFSET,
	};

	static struct ls_scfg_msi_cfg ls1043_v1_1_msi_cfg = {
	.ibs_shift = 2,
	.msir_irqs = MSI_LS1043V1_1_IRQS_PER_MSIR,
	.msir_base = MSI_LS1043V1_1_MSIR_OFFSET,
	};

	static const struct of_device_id ls_scfg_msi_id[] = {
	/* The following two misspelled compatibles are obsolete */
	{ .compatible = "fsl,1s1021a-msi", .data = &ls1021_msi_cfg},
	{ .compatible = "fsl,1s1043a-msi", .data = &ls1021_msi_cfg},

	{ .compatible = "fsl,ls1012a-msi", .data = &ls1021_msi_cfg },
	{ .compatible = "fsl,ls1021a-msi", .data = &ls1021_msi_cfg },
	{ .compatible = "fsl,ls1043a-msi", .data = &ls1021_msi_cfg },
	{ .compatible = "fsl,ls1043a-v1.1-msi", .data = &ls1043_v1_1_msi_cfg },
	{ .compatible = "fsl,ls1046a-msi", .data = &ls1046_msi_cfg },
	{},
	};
	MODULE_DEVICE_TABLE(of, ls_scfg_msi_id);

	static int ls_scfg_msi_probe(struct platform_device *pdev)
	{
	const struct of_device_id *match;
	struct ls_scfg_msi *msi_data;
	struct resource *res;
	int i, ret;

	match = of_match_device(ls_scfg_msi_id, &pdev->dev);
	if (!match)
	return -ENODEV;

	msi_data = devm_kzalloc(&pdev->dev, sizeof(*msi_data), GFP_KERNEL);
	if (!msi_data)
	return -ENOMEM;

	msi_data->cfg = (struct ls_scfg_msi_cfg *) match->data;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	msi_data->regs = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(msi_data->regs)) {
	dev_err(&pdev->dev, "failed to initialize 'regs'\n");
	return PTR_ERR(msi_data->regs);
	}
	msi_data->msiir_addr = res->start;

	msi_data->pdev = pdev;
	spin_lock_init(&msi_data->lock);

	msi_data->irqs_num = MSI_IRQS_PER_MSIR *
	(1 << msi_data->cfg->ibs_shift);
	msi_data->used = devm_kcalloc(&pdev->dev,
	BITS_TO_LONGS(msi_data->irqs_num),
	sizeof(*msi_data->used),
	GFP_KERNEL);
	if (!msi_data->used)
	return -ENOMEM;
	/*
	* Reserve all the hwirqs
	* The available hwirqs will be released in ls1_msi_setup_hwirq()
	*/
	bitmap_set(msi_data->used, 0, msi_data->irqs_num);

	msi_data->msir_num = of_irq_count(pdev->dev.of_node);

	if (msi_affinity_flag) {
	u32 cpu_num;

	cpu_num = num_possible_cpus();
	if (msi_data->msir_num >= cpu_num)
	msi_data->msir_num = cpu_num;
	else
	msi_affinity_flag = 0;
	}

	msi_data->msir = devm_kcalloc(&pdev->dev, msi_data->msir_num,
	sizeof(*msi_data->msir),
	GFP_KERNEL);
	if (!msi_data->msir)
	return -ENOMEM;

	for (i = 0; i < msi_data->msir_num; i++)
	ls_scfg_msi_setup_hwirq(msi_data, i);

	ret = ls_scfg_msi_domains_init(msi_data);
	if (ret)
	return ret;

	platform_set_drvdata(pdev, msi_data);

	return 0;
	}

	static int ls_scfg_msi_remove(struct platform_device *pdev)
	{
	struct ls_scfg_msi *msi_data = platform_get_drvdata(pdev);
	int i;

	for (i = 0; i < msi_data->msir_num; i++)
	ls_scfg_msi_teardown_hwirq(&msi_data->msir[i]);

	irq_domain_remove(msi_data->msi_domain);
	irq_domain_remove(msi_data->parent);

	platform_set_drvdata(pdev, NULL);

	return 0;
	}

	static struct platform_driver ls_scfg_msi_driver = {
	.driver = {
	.name = "ls-scfg-msi",
	.of_match_table = ls_scfg_msi_id,
	},
	.probe = ls_scfg_msi_probe,
	.remove = ls_scfg_msi_remove,
	};

	module_platform_driver(ls_scfg_msi_driver);

	MODULE_AUTHOR("Minghuan Lian <Minghuan.Lian@nxp.com>");
	MODULE_DESCRIPTION("Freescale Layerscape SCFG MSI controller driver");
	MODULE_LICENSE("GPL v2");