drivers/irqchip/irq-vf610-mscm-ir.c - linux/kernel/git/viro/vfs - Git at Google

 /*
  * Copyright (C) 2014-2015 Toradex AG
  * Author: Stefan Agner <stefan@agner.ch>
  *
  * 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.
  *
  *
  * IRQ chip driver for MSCM interrupt router available on Vybrid SoC's.
  * The interrupt router is between the CPU's interrupt controller and the
  * peripheral. The router allows to route the peripheral interrupts to
  * one of the two available CPU's on Vybrid VF6xx SoC's (Cortex-A5 or
  * Cortex-M4). The router will be configured transparently on a IRQ
  * request.
  *
  * o All peripheral interrupts of the Vybrid SoC can be routed to
  *   CPU 0, CPU 1 or both. The routing is useful for dual-core
  *   variants of Vybrid SoC such as VF6xx. This driver routes the
  *   requested interrupt to the CPU currently running on.
  *
  * o It is required to setup the interrupt router even on single-core
  *   variants of Vybrid.
  */

 #include <linux/cpu_pm.h>
 #include <linux/io.h>
 #include <linux/irq.h>
 #include <linux/irqchip.h>
 #include <linux/irqdomain.h>
 #include <linux/mfd/syscon.h>
 #include <dt-bindings/interrupt-controller/arm-gic.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
 #include <linux/slab.h>
 #include <linux/regmap.h>

 #define MSCM_CPxNUM		0x4

 #define MSCM_IRSPRC(n)		(0x80 + 2 * (n))
 #define MSCM_IRSPRC_CPEN_MASK	0x3

 #define MSCM_IRSPRC_NUM		112

 struct vf610_mscm_ir_chip_data {
 	void __iomem *mscm_ir_base;
 	u16 cpu_mask;
 	u16 saved_irsprc[MSCM_IRSPRC_NUM];
 	bool is_nvic;
 };

 static struct vf610_mscm_ir_chip_data *mscm_ir_data;

 static inline void vf610_mscm_ir_save(struct vf610_mscm_ir_chip_data *data)
 {
 	int i;

 	for (i = 0; i < MSCM_IRSPRC_NUM; i++)
 		data->saved_irsprc[i] = readw_relaxed(data->mscm_ir_base + MSCM_IRSPRC(i));
 }

 static inline void vf610_mscm_ir_restore(struct vf610_mscm_ir_chip_data *data)
 {
 	int i;

 	for (i = 0; i < MSCM_IRSPRC_NUM; i++)
 		writew_relaxed(data->saved_irsprc[i], data->mscm_ir_base + MSCM_IRSPRC(i));
 }

 static int vf610_mscm_ir_notifier(struct notifier_block *self,
 				  unsigned long cmd, void *v)
 {
 	switch (cmd) {
 	case CPU_CLUSTER_PM_ENTER:
 		vf610_mscm_ir_save(mscm_ir_data);
 		break;
 	case CPU_CLUSTER_PM_ENTER_FAILED:
 	case CPU_CLUSTER_PM_EXIT:
 		vf610_mscm_ir_restore(mscm_ir_data);
 		break;
 	}

 	return NOTIFY_OK;
 }

 static struct notifier_block mscm_ir_notifier_block = {
 	.notifier_call = vf610_mscm_ir_notifier,
 };

 static void vf610_mscm_ir_enable(struct irq_data *data)
 {
 	irq_hw_number_t hwirq = data->hwirq;
 	struct vf610_mscm_ir_chip_data *chip_data = data->chip_data;
 	u16 irsprc;

 	irsprc = readw_relaxed(chip_data->mscm_ir_base + MSCM_IRSPRC(hwirq));
 	irsprc &= MSCM_IRSPRC_CPEN_MASK;

 	WARN_ON(irsprc & ~chip_data->cpu_mask);

 	writew_relaxed(chip_data->cpu_mask,
 		       chip_data->mscm_ir_base + MSCM_IRSPRC(hwirq));

 	irq_chip_enable_parent(data);
 }

 static void vf610_mscm_ir_disable(struct irq_data *data)
 {
 	irq_hw_number_t hwirq = data->hwirq;
 	struct vf610_mscm_ir_chip_data *chip_data = data->chip_data;

 	writew_relaxed(0x0, chip_data->mscm_ir_base + MSCM_IRSPRC(hwirq));

 	irq_chip_disable_parent(data);
 }

 static struct irq_chip vf610_mscm_ir_irq_chip = {
 	.name			= "mscm-ir",
 	.irq_mask		= irq_chip_mask_parent,
 	.irq_unmask		= irq_chip_unmask_parent,
 	.irq_eoi		= irq_chip_eoi_parent,
 	.irq_enable		= vf610_mscm_ir_enable,
 	.irq_disable		= vf610_mscm_ir_disable,
 	.irq_retrigger		= irq_chip_retrigger_hierarchy,
 	.irq_set_affinity	= irq_chip_set_affinity_parent,
 };

 static int vf610_mscm_ir_domain_alloc(struct irq_domain *domain, unsigned int virq,
 				      unsigned int nr_irqs, void *arg)
 {
 	int i;
 	irq_hw_number_t hwirq;
 	struct irq_fwspec *fwspec = arg;
 	struct irq_fwspec parent_fwspec;

 	if (!irq_domain_get_of_node(domain->parent))
 		return -EINVAL;

 	if (fwspec->param_count != 2)
 		return -EINVAL;

 	hwirq = fwspec->param[0];
 	for (i = 0; i < nr_irqs; i++)
 		irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
 					      &vf610_mscm_ir_irq_chip,
 					      domain->host_data);

 	parent_fwspec.fwnode = domain->parent->fwnode;

 	if (mscm_ir_data->is_nvic) {
 		parent_fwspec.param_count = 1;
 		parent_fwspec.param[0] = fwspec->param[0];
 	} else {
 		parent_fwspec.param_count = 3;
 		parent_fwspec.param[0] = GIC_SPI;
 		parent_fwspec.param[1] = fwspec->param[0];
 		parent_fwspec.param[2] = fwspec->param[1];
 	}

 	return irq_domain_alloc_irqs_parent(domain, virq, nr_irqs,
 					    &parent_fwspec);
 }

 static int vf610_mscm_ir_domain_translate(struct irq_domain *d,
 					  struct irq_fwspec *fwspec,
 					  unsigned long *hwirq,
 					  unsigned int *type)
 {
 	if (WARN_ON(fwspec->param_count < 2))
 		return -EINVAL;
 	*hwirq = fwspec->param[0];
 	*type = fwspec->param[1] & IRQ_TYPE_SENSE_MASK;
 	return 0;
 }

 static const struct irq_domain_ops mscm_irq_domain_ops = {
 	.translate = vf610_mscm_ir_domain_translate,
 	.alloc = vf610_mscm_ir_domain_alloc,
 	.free = irq_domain_free_irqs_common,
 };

 static int __init vf610_mscm_ir_of_init(struct device_node *node,
 			       struct device_node *parent)
 {
 	struct irq_domain *domain, *domain_parent;
 	struct regmap *mscm_cp_regmap;
 	int ret, cpuid;

 	domain_parent = irq_find_host(parent);
 	if (!domain_parent) {
 		pr_err("vf610_mscm_ir: interrupt-parent not found\n");
 		return -EINVAL;
 	}

 	mscm_ir_data = kzalloc(sizeof(*mscm_ir_data), GFP_KERNEL);
 	if (!mscm_ir_data)
 		return -ENOMEM;

 	mscm_ir_data->mscm_ir_base = of_io_request_and_map(node, 0, "mscm-ir");
 	if (IS_ERR(mscm_ir_data->mscm_ir_base)) {
 		pr_err("vf610_mscm_ir: unable to map mscm register\n");
 		ret = PTR_ERR(mscm_ir_data->mscm_ir_base);
 		goto out_free;
 	}

 	mscm_cp_regmap = syscon_regmap_lookup_by_phandle(node, "fsl,cpucfg");
 	if (IS_ERR(mscm_cp_regmap)) {
 		ret = PTR_ERR(mscm_cp_regmap);
 		pr_err("vf610_mscm_ir: regmap lookup for cpucfg failed\n");
 		goto out_unmap;
 	}

 	regmap_read(mscm_cp_regmap, MSCM_CPxNUM, &cpuid);
 	mscm_ir_data->cpu_mask = 0x1 << cpuid;

 	domain = irq_domain_add_hierarchy(domain_parent, 0,
 					  MSCM_IRSPRC_NUM, node,
 					  &mscm_irq_domain_ops, mscm_ir_data);
 	if (!domain) {
 		ret = -ENOMEM;
 		goto out_unmap;
 	}

 	if (of_device_is_compatible(irq_domain_get_of_node(domain->parent),
 				    "arm,armv7m-nvic"))
 		mscm_ir_data->is_nvic = true;

 	cpu_pm_register_notifier(&mscm_ir_notifier_block);

 	return 0;

 out_unmap:
 	iounmap(mscm_ir_data->mscm_ir_base);
 out_free:
 	kfree(mscm_ir_data);
 	return ret;
 }
 IRQCHIP_DECLARE(vf610_mscm_ir, "fsl,vf610-mscm-ir", vf610_mscm_ir_of_init);
	/*
	* Copyright (C) 2014-2015 Toradex AG
	* Author: Stefan Agner <stefan@agner.ch>
	*
	* 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.
	*
	*
	* IRQ chip driver for MSCM interrupt router available on Vybrid SoC's.
	* The interrupt router is between the CPU's interrupt controller and the
	* peripheral. The router allows to route the peripheral interrupts to
	* one of the two available CPU's on Vybrid VF6xx SoC's (Cortex-A5 or
	* Cortex-M4). The router will be configured transparently on a IRQ
	* request.
	*
	* o All peripheral interrupts of the Vybrid SoC can be routed to
	* CPU 0, CPU 1 or both. The routing is useful for dual-core
	* variants of Vybrid SoC such as VF6xx. This driver routes the
	* requested interrupt to the CPU currently running on.
	*
	* o It is required to setup the interrupt router even on single-core
	* variants of Vybrid.
	*/

	#include <linux/cpu_pm.h>
	#include <linux/io.h>
	#include <linux/irq.h>
	#include <linux/irqchip.h>
	#include <linux/irqdomain.h>
	#include <linux/mfd/syscon.h>
	#include <dt-bindings/interrupt-controller/arm-gic.h>
	#include <linux/of.h>
	#include <linux/of_address.h>
	#include <linux/slab.h>
	#include <linux/regmap.h>

	#define MSCM_CPxNUM 0x4

	#define MSCM_IRSPRC(n) (0x80 + 2 * (n))
	#define MSCM_IRSPRC_CPEN_MASK 0x3

	#define MSCM_IRSPRC_NUM 112

	struct vf610_mscm_ir_chip_data {
	void __iomem *mscm_ir_base;
	u16 cpu_mask;
	u16 saved_irsprc[MSCM_IRSPRC_NUM];
	bool is_nvic;
	};

	static struct vf610_mscm_ir_chip_data *mscm_ir_data;

	static inline void vf610_mscm_ir_save(struct vf610_mscm_ir_chip_data *data)
	{
	int i;

	for (i = 0; i < MSCM_IRSPRC_NUM; i++)
	data->saved_irsprc[i] = readw_relaxed(data->mscm_ir_base + MSCM_IRSPRC(i));
	}

	static inline void vf610_mscm_ir_restore(struct vf610_mscm_ir_chip_data *data)
	{
	int i;

	for (i = 0; i < MSCM_IRSPRC_NUM; i++)
	writew_relaxed(data->saved_irsprc[i], data->mscm_ir_base + MSCM_IRSPRC(i));
	}

	static int vf610_mscm_ir_notifier(struct notifier_block *self,
	unsigned long cmd, void *v)
	{
	switch (cmd) {
	case CPU_CLUSTER_PM_ENTER:
	vf610_mscm_ir_save(mscm_ir_data);
	break;
	case CPU_CLUSTER_PM_ENTER_FAILED:
	case CPU_CLUSTER_PM_EXIT:
	vf610_mscm_ir_restore(mscm_ir_data);
	break;
	}

	return NOTIFY_OK;
	}

	static struct notifier_block mscm_ir_notifier_block = {
	.notifier_call = vf610_mscm_ir_notifier,
	};

	static void vf610_mscm_ir_enable(struct irq_data *data)
	{
	irq_hw_number_t hwirq = data->hwirq;
	struct vf610_mscm_ir_chip_data *chip_data = data->chip_data;
	u16 irsprc;

	irsprc = readw_relaxed(chip_data->mscm_ir_base + MSCM_IRSPRC(hwirq));
	irsprc &= MSCM_IRSPRC_CPEN_MASK;

	WARN_ON(irsprc & ~chip_data->cpu_mask);

	writew_relaxed(chip_data->cpu_mask,
	chip_data->mscm_ir_base + MSCM_IRSPRC(hwirq));

	irq_chip_enable_parent(data);
	}

	static void vf610_mscm_ir_disable(struct irq_data *data)
	{
	irq_hw_number_t hwirq = data->hwirq;
	struct vf610_mscm_ir_chip_data *chip_data = data->chip_data;

	writew_relaxed(0x0, chip_data->mscm_ir_base + MSCM_IRSPRC(hwirq));

	irq_chip_disable_parent(data);
	}

	static struct irq_chip vf610_mscm_ir_irq_chip = {
	.name = "mscm-ir",
	.irq_mask = irq_chip_mask_parent,
	.irq_unmask = irq_chip_unmask_parent,
	.irq_eoi = irq_chip_eoi_parent,
	.irq_enable = vf610_mscm_ir_enable,
	.irq_disable = vf610_mscm_ir_disable,
	.irq_retrigger = irq_chip_retrigger_hierarchy,
	.irq_set_affinity = irq_chip_set_affinity_parent,
	};

	static int vf610_mscm_ir_domain_alloc(struct irq_domain *domain, unsigned int virq,
	unsigned int nr_irqs, void *arg)
	{
	int i;
	irq_hw_number_t hwirq;
	struct irq_fwspec *fwspec = arg;
	struct irq_fwspec parent_fwspec;

	if (!irq_domain_get_of_node(domain->parent))
	return -EINVAL;

	if (fwspec->param_count != 2)
	return -EINVAL;

	hwirq = fwspec->param[0];
	for (i = 0; i < nr_irqs; i++)
	irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
	&vf610_mscm_ir_irq_chip,
	domain->host_data);

	parent_fwspec.fwnode = domain->parent->fwnode;

	if (mscm_ir_data->is_nvic) {
	parent_fwspec.param_count = 1;
	parent_fwspec.param[0] = fwspec->param[0];
	} else {
	parent_fwspec.param_count = 3;
	parent_fwspec.param[0] = GIC_SPI;
	parent_fwspec.param[1] = fwspec->param[0];
	parent_fwspec.param[2] = fwspec->param[1];
	}

	return irq_domain_alloc_irqs_parent(domain, virq, nr_irqs,
	&parent_fwspec);
	}

	static int vf610_mscm_ir_domain_translate(struct irq_domain *d,
	struct irq_fwspec *fwspec,
	unsigned long *hwirq,
	unsigned int *type)
	{
	if (WARN_ON(fwspec->param_count < 2))
	return -EINVAL;
	*hwirq = fwspec->param[0];
	*type = fwspec->param[1] & IRQ_TYPE_SENSE_MASK;
	return 0;
	}

	static const struct irq_domain_ops mscm_irq_domain_ops = {
	.translate = vf610_mscm_ir_domain_translate,
	.alloc = vf610_mscm_ir_domain_alloc,
	.free = irq_domain_free_irqs_common,
	};

	static int __init vf610_mscm_ir_of_init(struct device_node *node,
	struct device_node *parent)
	{
	struct irq_domain domain, domain_parent;
	struct regmap *mscm_cp_regmap;
	int ret, cpuid;

	domain_parent = irq_find_host(parent);
	if (!domain_parent) {
	pr_err("vf610_mscm_ir: interrupt-parent not found\n");
	return -EINVAL;
	}

	mscm_ir_data = kzalloc(sizeof(*mscm_ir_data), GFP_KERNEL);
	if (!mscm_ir_data)
	return -ENOMEM;

	mscm_ir_data->mscm_ir_base = of_io_request_and_map(node, 0, "mscm-ir");
	if (IS_ERR(mscm_ir_data->mscm_ir_base)) {
	pr_err("vf610_mscm_ir: unable to map mscm register\n");
	ret = PTR_ERR(mscm_ir_data->mscm_ir_base);
	goto out_free;
	}

	mscm_cp_regmap = syscon_regmap_lookup_by_phandle(node, "fsl,cpucfg");
	if (IS_ERR(mscm_cp_regmap)) {
	ret = PTR_ERR(mscm_cp_regmap);
	pr_err("vf610_mscm_ir: regmap lookup for cpucfg failed\n");
	goto out_unmap;
	}

	regmap_read(mscm_cp_regmap, MSCM_CPxNUM, &cpuid);
	mscm_ir_data->cpu_mask = 0x1 << cpuid;

	domain = irq_domain_add_hierarchy(domain_parent, 0,
	MSCM_IRSPRC_NUM, node,
	&mscm_irq_domain_ops, mscm_ir_data);
	if (!domain) {
	ret = -ENOMEM;
	goto out_unmap;
	}

	if (of_device_is_compatible(irq_domain_get_of_node(domain->parent),
	"arm,armv7m-nvic"))
	mscm_ir_data->is_nvic = true;

	cpu_pm_register_notifier(&mscm_ir_notifier_block);

	return 0;

	out_unmap:
	iounmap(mscm_ir_data->mscm_ir_base);
	out_free:
	kfree(mscm_ir_data);
	return ret;
	}
	IRQCHIP_DECLARE(vf610_mscm_ir, "fsl,vf610-mscm-ir", vf610_mscm_ir_of_init);