blob: fd94fe849af680f3edc24a3dcb184c308fa0613e [file] [log] [blame]
/*
* 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.
*
* Partially based on arch/mips/ralink/irq.c
*
* Copyright (C) 2009 Gabor Juhos <juhosg@openwrt.org>
* Copyright (C) 2013 John Crispin <blogic@openwrt.org>
* Copyright (C) 2014 Kevin Cernekee <cernekee@gmail.com>
*/
#include <linux/io.h>
#include <linux/bitops.h>
#include <linux/of_platform.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/irqdomain.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <asm/bmips.h>
#include <asm/irq_cpu.h>
#include <asm/mipsregs.h>
/* INTC register offsets */
#define INTC_REG_ENABLE 0x00
#define INTC_REG_STATUS 0x04
#define MAX_WORDS 2
#define IRQS_PER_WORD 32
struct bcm3384_intc {
int n_words;
void __iomem *reg[MAX_WORDS];
u32 enable[MAX_WORDS];
spinlock_t lock;
};
static void bcm3384_intc_irq_unmask(struct irq_data *d)
{
struct bcm3384_intc *priv = d->domain->host_data;
unsigned long flags;
int idx = d->hwirq / IRQS_PER_WORD;
int bit = d->hwirq % IRQS_PER_WORD;
spin_lock_irqsave(&priv->lock, flags);
priv->enable[idx] |= BIT(bit);
__raw_writel(priv->enable[idx], priv->reg[idx] + INTC_REG_ENABLE);
spin_unlock_irqrestore(&priv->lock, flags);
}
static void bcm3384_intc_irq_mask(struct irq_data *d)
{
struct bcm3384_intc *priv = d->domain->host_data;
unsigned long flags;
int idx = d->hwirq / IRQS_PER_WORD;
int bit = d->hwirq % IRQS_PER_WORD;
spin_lock_irqsave(&priv->lock, flags);
priv->enable[idx] &= ~BIT(bit);
__raw_writel(priv->enable[idx], priv->reg[idx] + INTC_REG_ENABLE);
spin_unlock_irqrestore(&priv->lock, flags);
}
static struct irq_chip bcm3384_intc_irq_chip = {
.name = "INTC",
.irq_unmask = bcm3384_intc_irq_unmask,
.irq_mask = bcm3384_intc_irq_mask,
.irq_mask_ack = bcm3384_intc_irq_mask,
};
unsigned int get_c0_compare_int(void)
{
return CP0_LEGACY_COMPARE_IRQ;
}
static void bcm3384_intc_irq_handler(unsigned int irq, struct irq_desc *desc)
{
struct irq_domain *domain = irq_get_handler_data(irq);
struct bcm3384_intc *priv = domain->host_data;
unsigned long flags;
unsigned int idx;
for (idx = 0; idx < priv->n_words; idx++) {
unsigned long pending;
int hwirq;
spin_lock_irqsave(&priv->lock, flags);
pending = __raw_readl(priv->reg[idx] + INTC_REG_STATUS) &
priv->enable[idx];
spin_unlock_irqrestore(&priv->lock, flags);
for_each_set_bit(hwirq, &pending, IRQS_PER_WORD) {
generic_handle_irq(irq_find_mapping(domain,
hwirq + idx * IRQS_PER_WORD));
}
}
}
asmlinkage void plat_irq_dispatch(void)
{
unsigned long pending =
(read_c0_status() & read_c0_cause() & ST0_IM) >> STATUSB_IP0;
int bit;
for_each_set_bit(bit, &pending, 8)
do_IRQ(MIPS_CPU_IRQ_BASE + bit);
}
static int intc_map(struct irq_domain *d, unsigned int irq, irq_hw_number_t hw)
{
irq_set_chip_and_handler(irq, &bcm3384_intc_irq_chip, handle_level_irq);
return 0;
}
static const struct irq_domain_ops irq_domain_ops = {
.xlate = irq_domain_xlate_onecell,
.map = intc_map,
};
static int __init ioremap_one_pair(struct bcm3384_intc *priv,
struct device_node *node,
int idx)
{
struct resource res;
if (of_address_to_resource(node, idx, &res))
return 0;
if (request_mem_region(res.start, resource_size(&res),
res.name) < 0)
pr_err("Failed to request INTC register region\n");
priv->reg[idx] = ioremap_nocache(res.start, resource_size(&res));
if (!priv->reg[idx])
panic("Failed to ioremap INTC register range");
/* start up with everything masked before we hook the parent IRQ */
__raw_writel(0, priv->reg[idx] + INTC_REG_ENABLE);
priv->enable[idx] = 0;
return IRQS_PER_WORD;
}
static int __init intc_of_init(struct device_node *node,
struct device_node *parent)
{
struct irq_domain *domain;
unsigned int parent_irq, n_irqs = 0;
struct bcm3384_intc *priv;
priv = kzalloc(sizeof(*priv), GFP_KERNEL);
if (!priv)
panic("Failed to allocate bcm3384_intc struct");
spin_lock_init(&priv->lock);
parent_irq = irq_of_parse_and_map(node, 0);
if (!parent_irq)
panic("Failed to get INTC IRQ");
n_irqs += ioremap_one_pair(priv, node, 0);
n_irqs += ioremap_one_pair(priv, node, 1);
if (!n_irqs)
panic("Failed to map INTC registers");
priv->n_words = n_irqs / IRQS_PER_WORD;
domain = irq_domain_add_linear(node, n_irqs, &irq_domain_ops, priv);
if (!domain)
panic("Failed to add irqdomain");
irq_set_chained_handler(parent_irq, bcm3384_intc_irq_handler);
irq_set_handler_data(parent_irq, domain);
return 0;
}
static struct of_device_id of_irq_ids[] __initdata = {
{ .compatible = "mti,cpu-interrupt-controller",
.data = mips_cpu_irq_of_init },
{ .compatible = "brcm,bcm3384-intc",
.data = intc_of_init },
{},
};
void __init arch_init_irq(void)
{
bmips_tp1_irqs = 0;
of_irq_init(of_irq_ids);
}