drivers/irqchip/irq-bcm7038-l1.c - kernel/bruno - Git at Google

 /*
  * Broadcom BCM7038 style Level 1 interrupt controller driver
  *
  * Copyright (C) 2014 Broadcom Corporation
  * Author: Kevin Cernekee
  *
  * 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.
  */

 #define pr_fmt(fmt)	KBUILD_MODNAME	": " fmt

 #include <linux/bitops.h>
 #include <linux/kconfig.h>
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
 #include <linux/ioport.h>
 #include <linux/irq.h>
 #include <linux/irqdomain.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/of_irq.h>
 #include <linux/of_address.h>
 #include <linux/of_platform.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
 #include <linux/smp.h>
 #include <linux/types.h>
 #include <linux/irqchip.h>
 #include <linux/irqchip/chained_irq.h>

 #define IRQS_PER_WORD		32
 #define REG_BYTES_PER_IRQ_WORD	(sizeof(u32) * 4)
 #define MAX_WORDS		8

 struct bcm7038_l1_cpu;

 struct bcm7038_l1_chip {
 	raw_spinlock_t		lock;
 	unsigned int		n_words;
 	struct irq_domain	*domain;
 	struct bcm7038_l1_cpu	*cpus[NR_CPUS];
 	u8			affinity[MAX_WORDS * IRQS_PER_WORD];
 };

 struct bcm7038_l1_cpu {
 	void __iomem		*map_base;
 	u32			mask_cache[0];
 };

 /*
  * STATUS/MASK_STATUS/MASK_SET/MASK_CLEAR are packed one right after another:
  *
  * 7038:
  *   0x1000_1400: W0_STATUS
  *   0x1000_1404: W1_STATUS
  *   0x1000_1408: W0_MASK_STATUS
  *   0x1000_140c: W1_MASK_STATUS
  *   0x1000_1410: W0_MASK_SET
  *   0x1000_1414: W1_MASK_SET
  *   0x1000_1418: W0_MASK_CLEAR
  *   0x1000_141c: W1_MASK_CLEAR
  *
  * 7445:
  *   0xf03e_1500: W0_STATUS
  *   0xf03e_1504: W1_STATUS
  *   0xf03e_1508: W2_STATUS
  *   0xf03e_150c: W3_STATUS
  *   0xf03e_1510: W4_STATUS
  *   0xf03e_1514: W0_MASK_STATUS
  *   0xf03e_1518: W1_MASK_STATUS
  *   [...]
  */

 static inline unsigned int reg_status(struct bcm7038_l1_chip *intc,
 				      unsigned int word)
 {
 	return (0 * intc->n_words + word) * sizeof(u32);
 }

 static inline unsigned int reg_mask_status(struct bcm7038_l1_chip *intc,
 					   unsigned int word)
 {
 	return (1 * intc->n_words + word) * sizeof(u32);
 }

 static inline unsigned int reg_mask_set(struct bcm7038_l1_chip *intc,
 					unsigned int word)
 {
 	return (2 * intc->n_words + word) * sizeof(u32);
 }

 static inline unsigned int reg_mask_clr(struct bcm7038_l1_chip *intc,
 					unsigned int word)
 {
 	return (3 * intc->n_words + word) * sizeof(u32);
 }

 static inline u32 l1_readl(void __iomem *reg)
 {
 	if (IS_ENABLED(CONFIG_MIPS) && IS_ENABLED(CONFIG_CPU_BIG_ENDIAN))
 		return ioread32be(reg);
 	else
 		return readl(reg);
 }

 static inline void l1_writel(u32 val, void __iomem *reg)
 {
 	if (IS_ENABLED(CONFIG_MIPS) && IS_ENABLED(CONFIG_CPU_BIG_ENDIAN))
 		iowrite32be(val, reg);
 	else
 		writel(val, reg);
 }

 static void bcm7038_l1_irq_handle(struct irq_desc *desc)
 {
 	struct bcm7038_l1_chip *intc = irq_desc_get_handler_data(desc);
 	struct bcm7038_l1_cpu *cpu;
 	struct irq_chip *chip = irq_desc_get_chip(desc);
 	unsigned int idx;

 #ifdef CONFIG_SMP
 	cpu = intc->cpus[cpu_logical_map(smp_processor_id())];
 #else
 	cpu = intc->cpus[0];
 #endif

 	chained_irq_enter(chip, desc);

 	for (idx = 0; idx < intc->n_words; idx++) {
 		int base = idx * IRQS_PER_WORD;
 		unsigned long pending, flags;
 		int hwirq;

 		raw_spin_lock_irqsave(&intc->lock, flags);
 		pending = l1_readl(cpu->map_base + reg_status(intc, idx)) &
 			  ~cpu->mask_cache[idx];
 		raw_spin_unlock_irqrestore(&intc->lock, flags);

 		for_each_set_bit(hwirq, &pending, IRQS_PER_WORD) {
 			generic_handle_irq(irq_find_mapping(intc->domain,
 							    base + hwirq));
 		}
 	}

 	chained_irq_exit(chip, desc);
 }

 static void __bcm7038_l1_unmask(struct irq_data *d, unsigned int cpu_idx)
 {
 	struct bcm7038_l1_chip *intc = irq_data_get_irq_chip_data(d);
 	u32 word = d->hwirq / IRQS_PER_WORD;
 	u32 mask = BIT(d->hwirq % IRQS_PER_WORD);

 	intc->cpus[cpu_idx]->mask_cache[word] &= ~mask;
 	l1_writel(mask, intc->cpus[cpu_idx]->map_base +
 			reg_mask_clr(intc, word));
 }

 static void __bcm7038_l1_mask(struct irq_data *d, unsigned int cpu_idx)
 {
 	struct bcm7038_l1_chip *intc = irq_data_get_irq_chip_data(d);
 	u32 word = d->hwirq / IRQS_PER_WORD;
 	u32 mask = BIT(d->hwirq % IRQS_PER_WORD);

 	intc->cpus[cpu_idx]->mask_cache[word] |= mask;
 	l1_writel(mask, intc->cpus[cpu_idx]->map_base +
 			reg_mask_set(intc, word));
 }

 static void bcm7038_l1_unmask(struct irq_data *d)
 {
 	struct bcm7038_l1_chip *intc = irq_data_get_irq_chip_data(d);
 	unsigned long flags;

 	raw_spin_lock_irqsave(&intc->lock, flags);
 	__bcm7038_l1_unmask(d, intc->affinity[d->hwirq]);
 	raw_spin_unlock_irqrestore(&intc->lock, flags);
 }

 static void bcm7038_l1_mask(struct irq_data *d)
 {
 	struct bcm7038_l1_chip *intc = irq_data_get_irq_chip_data(d);
 	unsigned long flags;

 	raw_spin_lock_irqsave(&intc->lock, flags);
 	__bcm7038_l1_mask(d, intc->affinity[d->hwirq]);
 	raw_spin_unlock_irqrestore(&intc->lock, flags);
 }

 static int bcm7038_l1_set_affinity(struct irq_data *d,
 				   const struct cpumask *dest,
 				   bool force)
 {
 	struct bcm7038_l1_chip *intc = irq_data_get_irq_chip_data(d);
 	unsigned long flags;
 	irq_hw_number_t hw = d->hwirq;
 	u32 word = hw / IRQS_PER_WORD;
 	u32 mask = BIT(hw % IRQS_PER_WORD);
 	unsigned int first_cpu = cpumask_any_and(dest, cpu_online_mask);
 	bool was_disabled;

 	raw_spin_lock_irqsave(&intc->lock, flags);

 	was_disabled = !!(intc->cpus[intc->affinity[hw]]->mask_cache[word] &
 			  mask);
 	__bcm7038_l1_mask(d, intc->affinity[hw]);
 	intc->affinity[hw] = first_cpu;
 	if (!was_disabled)
 		__bcm7038_l1_unmask(d, first_cpu);

 	raw_spin_unlock_irqrestore(&intc->lock, flags);
 	return 0;
 }

 static int __init bcm7038_l1_init_one(struct device_node *dn,
 				      unsigned int idx,
 				      struct bcm7038_l1_chip *intc)
 {
 	struct resource res;
 	resource_size_t sz;
 	struct bcm7038_l1_cpu *cpu;
 	unsigned int i, n_words, parent_irq;

 	if (of_address_to_resource(dn, idx, &res))
 		return -EINVAL;
 	sz = resource_size(&res);
 	n_words = sz / REG_BYTES_PER_IRQ_WORD;

 	if (n_words > MAX_WORDS)
 		return -EINVAL;
 	else if (!intc->n_words)
 		intc->n_words = n_words;
 	else if (intc->n_words != n_words)
 		return -EINVAL;

 	cpu = intc->cpus[idx] = kzalloc(sizeof(*cpu) + n_words * sizeof(u32),
 					GFP_KERNEL);
 	if (!cpu)
 		return -ENOMEM;

 	cpu->map_base = ioremap(res.start, sz);
 	if (!cpu->map_base)
 		return -ENOMEM;

 	for (i = 0; i < n_words; i++) {
 		l1_writel(0xffffffff, cpu->map_base + reg_mask_set(intc, i));
 		cpu->mask_cache[i] = 0xffffffff;
 	}

 	parent_irq = irq_of_parse_and_map(dn, idx);
 	if (!parent_irq) {
 		pr_err("failed to map parent interrupt %d\n", parent_irq);
 		return -EINVAL;
 	}
 	irq_set_chained_handler_and_data(parent_irq, bcm7038_l1_irq_handle,
 					 intc);

 	return 0;
 }

 static struct irq_chip bcm7038_l1_irq_chip = {
 	.name			= "bcm7038-l1",
 	.irq_mask		= bcm7038_l1_mask,
 	.irq_unmask		= bcm7038_l1_unmask,
 	.irq_set_affinity	= bcm7038_l1_set_affinity,
 };

 static int bcm7038_l1_map(struct irq_domain *d, unsigned int virq,
 			  irq_hw_number_t hw_irq)
 {
 	irq_set_chip_and_handler(virq, &bcm7038_l1_irq_chip, handle_level_irq);
 	irq_set_chip_data(virq, d->host_data);
 	return 0;
 }

 static const struct irq_domain_ops bcm7038_l1_domain_ops = {
 	.xlate			= irq_domain_xlate_onecell,
 	.map			= bcm7038_l1_map,
 };

 int __init bcm7038_l1_of_init(struct device_node *dn,
 			      struct device_node *parent)
 {
 	struct bcm7038_l1_chip *intc;
 	int idx, ret;

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

 	raw_spin_lock_init(&intc->lock);
 	for_each_possible_cpu(idx) {
 		ret = bcm7038_l1_init_one(dn, idx, intc);
 		if (ret < 0) {
 			if (idx)
 				break;
 			pr_err("failed to remap intc L1 registers\n");
 			goto out_free;
 		}
 	}

 	intc->domain = irq_domain_add_linear(dn, IRQS_PER_WORD * intc->n_words,
 					     &bcm7038_l1_domain_ops,
 					     intc);
 	if (!intc->domain) {
 		ret = -ENOMEM;
 		goto out_unmap;
 	}

 	pr_info("registered BCM7038 L1 intc (mem: 0x%p, IRQs: %d)\n",
 		intc->cpus[0]->map_base, IRQS_PER_WORD * intc->n_words);

 	return 0;

 out_unmap:
 	for_each_possible_cpu(idx) {
 		struct bcm7038_l1_cpu *cpu = intc->cpus[idx];

 		if (cpu) {
 			if (cpu->map_base)
 				iounmap(cpu->map_base);
 			kfree(cpu);
 		}
 	}
 out_free:
 	kfree(intc);
 	return ret;
 }

 IRQCHIP_DECLARE(bcm7038_l1, "brcm,bcm7038-l1-intc", bcm7038_l1_of_init);
	/*
	* Broadcom BCM7038 style Level 1 interrupt controller driver
	*
	* Copyright (C) 2014 Broadcom Corporation
	* Author: Kevin Cernekee
	*
	* 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.
	*/

	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

	#include <linux/bitops.h>
	#include <linux/kconfig.h>
	#include <linux/kernel.h>
	#include <linux/init.h>
	#include <linux/interrupt.h>
	#include <linux/io.h>
	#include <linux/ioport.h>
	#include <linux/irq.h>
	#include <linux/irqdomain.h>
	#include <linux/module.h>
	#include <linux/of.h>
	#include <linux/of_irq.h>
	#include <linux/of_address.h>
	#include <linux/of_platform.h>
	#include <linux/platform_device.h>
	#include <linux/slab.h>
	#include <linux/smp.h>
	#include <linux/types.h>
	#include <linux/irqchip.h>
	#include <linux/irqchip/chained_irq.h>

	#define IRQS_PER_WORD 32
	#define REG_BYTES_PER_IRQ_WORD (sizeof(u32) * 4)
	#define MAX_WORDS 8

	struct bcm7038_l1_cpu;

	struct bcm7038_l1_chip {
	raw_spinlock_t lock;
	unsigned int n_words;
	struct irq_domain *domain;
	struct bcm7038_l1_cpu *cpus[NR_CPUS];
	u8 affinity[MAX_WORDS * IRQS_PER_WORD];
	};

	struct bcm7038_l1_cpu {
	void __iomem *map_base;
	u32 mask_cache[0];
	};

	/*
	* STATUS/MASK_STATUS/MASK_SET/MASK_CLEAR are packed one right after another:
	*
	* 7038:
	* 0x1000_1400: W0_STATUS
	* 0x1000_1404: W1_STATUS
	* 0x1000_1408: W0_MASK_STATUS
	* 0x1000_140c: W1_MASK_STATUS
	* 0x1000_1410: W0_MASK_SET
	* 0x1000_1414: W1_MASK_SET
	* 0x1000_1418: W0_MASK_CLEAR
	* 0x1000_141c: W1_MASK_CLEAR
	*
	* 7445:
	* 0xf03e_1500: W0_STATUS
	* 0xf03e_1504: W1_STATUS
	* 0xf03e_1508: W2_STATUS
	* 0xf03e_150c: W3_STATUS
	* 0xf03e_1510: W4_STATUS
	* 0xf03e_1514: W0_MASK_STATUS
	* 0xf03e_1518: W1_MASK_STATUS
	* [...]
	*/

	static inline unsigned int reg_status(struct bcm7038_l1_chip *intc,
	unsigned int word)
	{
	return (0 * intc->n_words + word) * sizeof(u32);
	}

	static inline unsigned int reg_mask_status(struct bcm7038_l1_chip *intc,
	unsigned int word)
	{
	return (1 * intc->n_words + word) * sizeof(u32);
	}

	static inline unsigned int reg_mask_set(struct bcm7038_l1_chip *intc,
	unsigned int word)
	{
	return (2 * intc->n_words + word) * sizeof(u32);
	}

	static inline unsigned int reg_mask_clr(struct bcm7038_l1_chip *intc,
	unsigned int word)
	{
	return (3 * intc->n_words + word) * sizeof(u32);
	}

	static inline u32 l1_readl(void __iomem *reg)
	{
	if (IS_ENABLED(CONFIG_MIPS) && IS_ENABLED(CONFIG_CPU_BIG_ENDIAN))
	return ioread32be(reg);
	else
	return readl(reg);
	}

	static inline void l1_writel(u32 val, void __iomem *reg)
	{
	if (IS_ENABLED(CONFIG_MIPS) && IS_ENABLED(CONFIG_CPU_BIG_ENDIAN))
	iowrite32be(val, reg);
	else
	writel(val, reg);
	}

	static void bcm7038_l1_irq_handle(struct irq_desc *desc)
	{
	struct bcm7038_l1_chip *intc = irq_desc_get_handler_data(desc);
	struct bcm7038_l1_cpu *cpu;
	struct irq_chip *chip = irq_desc_get_chip(desc);
	unsigned int idx;

	#ifdef CONFIG_SMP
	cpu = intc->cpus[cpu_logical_map(smp_processor_id())];
	#else
	cpu = intc->cpus[0];
	#endif

	chained_irq_enter(chip, desc);

	for (idx = 0; idx < intc->n_words; idx++) {
	int base = idx * IRQS_PER_WORD;
	unsigned long pending, flags;
	int hwirq;

	raw_spin_lock_irqsave(&intc->lock, flags);
	pending = l1_readl(cpu->map_base + reg_status(intc, idx)) &
	~cpu->mask_cache[idx];
	raw_spin_unlock_irqrestore(&intc->lock, flags);

	for_each_set_bit(hwirq, &pending, IRQS_PER_WORD) {
	generic_handle_irq(irq_find_mapping(intc->domain,
	base + hwirq));
	}
	}

	chained_irq_exit(chip, desc);
	}

	static void __bcm7038_l1_unmask(struct irq_data *d, unsigned int cpu_idx)
	{
	struct bcm7038_l1_chip *intc = irq_data_get_irq_chip_data(d);
	u32 word = d->hwirq / IRQS_PER_WORD;
	u32 mask = BIT(d->hwirq % IRQS_PER_WORD);

	intc->cpus[cpu_idx]->mask_cache[word] &= ~mask;
	l1_writel(mask, intc->cpus[cpu_idx]->map_base +
	reg_mask_clr(intc, word));
	}

	static void __bcm7038_l1_mask(struct irq_data *d, unsigned int cpu_idx)
	{
	struct bcm7038_l1_chip *intc = irq_data_get_irq_chip_data(d);
	u32 word = d->hwirq / IRQS_PER_WORD;
	u32 mask = BIT(d->hwirq % IRQS_PER_WORD);

	intc->cpus[cpu_idx]->mask_cache[word] \|= mask;
	l1_writel(mask, intc->cpus[cpu_idx]->map_base +
	reg_mask_set(intc, word));
	}

	static void bcm7038_l1_unmask(struct irq_data *d)
	{
	struct bcm7038_l1_chip *intc = irq_data_get_irq_chip_data(d);
	unsigned long flags;

	raw_spin_lock_irqsave(&intc->lock, flags);
	__bcm7038_l1_unmask(d, intc->affinity[d->hwirq]);
	raw_spin_unlock_irqrestore(&intc->lock, flags);
	}

	static void bcm7038_l1_mask(struct irq_data *d)
	{
	struct bcm7038_l1_chip *intc = irq_data_get_irq_chip_data(d);
	unsigned long flags;

	raw_spin_lock_irqsave(&intc->lock, flags);
	__bcm7038_l1_mask(d, intc->affinity[d->hwirq]);
	raw_spin_unlock_irqrestore(&intc->lock, flags);
	}

	static int bcm7038_l1_set_affinity(struct irq_data *d,
	const struct cpumask *dest,
	bool force)
	{
	struct bcm7038_l1_chip *intc = irq_data_get_irq_chip_data(d);
	unsigned long flags;
	irq_hw_number_t hw = d->hwirq;
	u32 word = hw / IRQS_PER_WORD;
	u32 mask = BIT(hw % IRQS_PER_WORD);
	unsigned int first_cpu = cpumask_any_and(dest, cpu_online_mask);
	bool was_disabled;

	raw_spin_lock_irqsave(&intc->lock, flags);

	was_disabled = !!(intc->cpus[intc->affinity[hw]]->mask_cache[word] &
	mask);
	__bcm7038_l1_mask(d, intc->affinity[hw]);
	intc->affinity[hw] = first_cpu;
	if (!was_disabled)
	__bcm7038_l1_unmask(d, first_cpu);

	raw_spin_unlock_irqrestore(&intc->lock, flags);
	return 0;
	}

	static int __init bcm7038_l1_init_one(struct device_node *dn,
	unsigned int idx,
	struct bcm7038_l1_chip *intc)
	{
	struct resource res;
	resource_size_t sz;
	struct bcm7038_l1_cpu *cpu;
	unsigned int i, n_words, parent_irq;

	if (of_address_to_resource(dn, idx, &res))
	return -EINVAL;
	sz = resource_size(&res);
	n_words = sz / REG_BYTES_PER_IRQ_WORD;

	if (n_words > MAX_WORDS)
	return -EINVAL;
	else if (!intc->n_words)
	intc->n_words = n_words;
	else if (intc->n_words != n_words)
	return -EINVAL;

	cpu = intc->cpus[idx] = kzalloc(sizeof(cpu) + n_words sizeof(u32),
	GFP_KERNEL);
	if (!cpu)
	return -ENOMEM;

	cpu->map_base = ioremap(res.start, sz);
	if (!cpu->map_base)
	return -ENOMEM;

	for (i = 0; i < n_words; i++) {
	l1_writel(0xffffffff, cpu->map_base + reg_mask_set(intc, i));
	cpu->mask_cache[i] = 0xffffffff;
	}

	parent_irq = irq_of_parse_and_map(dn, idx);
	if (!parent_irq) {
	pr_err("failed to map parent interrupt %d\n", parent_irq);
	return -EINVAL;
	}
	irq_set_chained_handler_and_data(parent_irq, bcm7038_l1_irq_handle,
	intc);

	return 0;
	}

	static struct irq_chip bcm7038_l1_irq_chip = {
	.name = "bcm7038-l1",
	.irq_mask = bcm7038_l1_mask,
	.irq_unmask = bcm7038_l1_unmask,
	.irq_set_affinity = bcm7038_l1_set_affinity,
	};

	static int bcm7038_l1_map(struct irq_domain *d, unsigned int virq,
	irq_hw_number_t hw_irq)
	{
	irq_set_chip_and_handler(virq, &bcm7038_l1_irq_chip, handle_level_irq);
	irq_set_chip_data(virq, d->host_data);
	return 0;
	}

	static const struct irq_domain_ops bcm7038_l1_domain_ops = {
	.xlate = irq_domain_xlate_onecell,
	.map = bcm7038_l1_map,
	};

	int __init bcm7038_l1_of_init(struct device_node *dn,
	struct device_node *parent)
	{
	struct bcm7038_l1_chip *intc;
	int idx, ret;

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

	raw_spin_lock_init(&intc->lock);
	for_each_possible_cpu(idx) {
	ret = bcm7038_l1_init_one(dn, idx, intc);
	if (ret < 0) {
	if (idx)
	break;
	pr_err("failed to remap intc L1 registers\n");
	goto out_free;
	}
	}

	intc->domain = irq_domain_add_linear(dn, IRQS_PER_WORD * intc->n_words,
	&bcm7038_l1_domain_ops,
	intc);
	if (!intc->domain) {
	ret = -ENOMEM;
	goto out_unmap;
	}

	pr_info("registered BCM7038 L1 intc (mem: 0x%p, IRQs: %d)\n",
	intc->cpus[0]->map_base, IRQS_PER_WORD * intc->n_words);

	return 0;

	out_unmap:
	for_each_possible_cpu(idx) {
	struct bcm7038_l1_cpu *cpu = intc->cpus[idx];

	if (cpu) {
	if (cpu->map_base)
	iounmap(cpu->map_base);
	kfree(cpu);
	}
	}
	out_free:
	kfree(intc);
	return ret;
	}

	IRQCHIP_DECLARE(bcm7038_l1, "brcm,bcm7038-l1-intc", bcm7038_l1_of_init);