/*
* Copyright (c) 2010-2011 Samsung Electronics Co., Ltd.
* http://www.samsung.com
*
* Combiner irqchip for EXYNOS
*
* 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/err.h>
#include <linux/export.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/irqdomain.h>
#include <linux/irqchip/chained_irq.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <asm/mach/irq.h>
#include "irqchip.h"
#define COMBINER_ENABLE_SET 0x0
#define COMBINER_ENABLE_CLEAR 0x4
#define COMBINER_INT_STATUS 0xC
#define IRQ_IN_COMBINER 8
static DEFINE_SPINLOCK(irq_controller_lock);
struct combiner_chip_data {
unsigned int hwirq_offset;
unsigned int irq_mask;
void __iomem *base;
unsigned int parent_irq;
};
static struct irq_domain *combiner_irq_domain;
static inline void __iomem *combiner_base(struct irq_data *data)
{
struct combiner_chip_data *combiner_data =
irq_data_get_irq_chip_data(data);
return combiner_data->base;
}
static void combiner_mask_irq(struct irq_data *data)
{
u32 mask = 1 << (data->hwirq % 32);
__raw_writel(mask, combiner_base(data) + COMBINER_ENABLE_CLEAR);
}
static void combiner_unmask_irq(struct irq_data *data)
{
u32 mask = 1 << (data->hwirq % 32);
__raw_writel(mask, combiner_base(data) + COMBINER_ENABLE_SET);
}
static void combiner_handle_cascade_irq(unsigned int irq, struct irq_desc *desc)
{
struct combiner_chip_data *chip_data = irq_get_handler_data(irq);
struct irq_chip *chip = irq_get_chip(irq);
unsigned int cascade_irq, combiner_irq;
unsigned long status;
chained_irq_enter(chip, desc);
spin_lock(&irq_controller_lock);
status = __raw_readl(chip_data->base + COMBINER_INT_STATUS);
spin_unlock(&irq_controller_lock);
status &= chip_data->irq_mask;
if (status == 0)
goto out;
combiner_irq = chip_data->hwirq_offset + __ffs(status);
cascade_irq = irq_find_mapping(combiner_irq_domain, combiner_irq);
if (unlikely(!cascade_irq))
do_bad_IRQ(irq, desc);
else
generic_handle_irq(cascade_irq);
out:
chained_irq_exit(chip, desc);
}
#ifdef CONFIG_SMP
static int combiner_set_affinity(struct irq_data *d,
const struct cpumask *mask_val, bool force)
{
struct combiner_chip_data *chip_data = irq_data_get_irq_chip_data(d);
struct irq_chip *chip = irq_get_chip(chip_data->parent_irq);
struct irq_data *data = irq_get_irq_data(chip_data->parent_irq);
if (chip && chip->irq_set_affinity)
return chip->irq_set_affinity(data, mask_val, force);
else
return -EINVAL;
}
#endif
static struct irq_chip combiner_chip = {
.name = "COMBINER",
.irq_mask = combiner_mask_irq,
.irq_unmask = combiner_unmask_irq,
#ifdef CONFIG_SMP
.irq_set_affinity = combiner_set_affinity,
#endif
};
static void __init combiner_cascade_irq(struct combiner_chip_data *combiner_data,
unsigned int irq)
{
if (irq_set_handler_data(irq, combiner_data) != 0)
BUG();
irq_set_chained_handler(irq, combiner_handle_cascade_irq);
}
static void __init combiner_init_one(struct combiner_chip_data *combiner_data,
unsigned int combiner_nr,
void __iomem *base, unsigned int irq)
{
combiner_data->base = base;
combiner_data->hwirq_offset = (combiner_nr & ~3) * IRQ_IN_COMBINER;
combiner_data->irq_mask = 0xff << ((combiner_nr % 4) << 3);
combiner_data->parent_irq = irq;
/* Disable all interrupts */
__raw_writel(combiner_data->irq_mask, base + COMBINER_ENABLE_CLEAR);
}
static int combiner_irq_domain_xlate(struct irq_domain *d,
struct device_node *controller,
const u32 *intspec, unsigned int intsize,
unsigned long *out_hwirq,
unsigned int *out_type)
{
if (d->of_node != controller)
return -EINVAL;
if (intsize < 2)
return -EINVAL;
*out_hwirq = intspec[0] * IRQ_IN_COMBINER + intspec[1];
*out_type = 0;
return 0;
}
static int combiner_irq_domain_map(struct irq_domain *d, unsigned int irq,
irq_hw_number_t hw)
{
struct combiner_chip_data *combiner_data = d->host_data;
irq_set_chip_and_handler(irq, &combiner_chip, handle_level_irq);
irq_set_chip_data(irq, &combiner_data[hw >> 3]);
set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
return 0;
}
static struct irq_domain_ops combiner_irq_domain_ops = {
.xlate = combiner_irq_domain_xlate,
.map = combiner_irq_domain_map,
};
static void __init combiner_init(void __iomem *combiner_base,
struct device_node *np,
unsigned int max_nr,
int irq_base)
{
int i, irq;
unsigned int nr_irq;
struct combiner_chip_data *combiner_data;
nr_irq = max_nr * IRQ_IN_COMBINER;
combiner_data = kcalloc(max_nr, sizeof (*combiner_data), GFP_KERNEL);
if (!combiner_data) {
pr_warning("%s: could not allocate combiner data\n", __func__);
return;
}
combiner_irq_domain = irq_domain_add_simple(np, nr_irq, irq_base,
&combiner_irq_domain_ops, combiner_data);
if (WARN_ON(!combiner_irq_domain)) {
pr_warning("%s: irq domain init failed\n", __func__);
return;
}
for (i = 0; i < max_nr; i++) {
irq = irq_of_parse_and_map(np, i);
combiner_init_one(&combiner_data[i], i,
combiner_base + (i >> 2) * 0x10, irq);
combiner_cascade_irq(&combiner_data[i], irq);
}
}
static int __init combiner_of_init(struct device_node *np,
struct device_node *parent)
{
void __iomem *combiner_base;
unsigned int max_nr = 20;
int irq_base = -1;
combiner_base = of_iomap(np, 0);
if (!combiner_base) {
pr_err("%s: failed to map combiner registers\n", __func__);
return -ENXIO;
}
if (of_property_read_u32(np, "samsung,combiner-nr", &max_nr)) {
pr_info("%s: number of combiners not specified, "
"setting default as %d.\n",
__func__, max_nr);
}
/*
* FIXME: This is a hardwired COMBINER_IRQ(0,0). Once all devices
* get their IRQ from DT, remove this in order to get dynamic
* allocation.
*/
irq_base = 160;
combiner_init(combiner_base, np, max_nr, irq_base);
return 0;
}
IRQCHIP_DECLARE(exynos4210_combiner, "samsung,exynos4210-combiner",
combiner_of_init);
