linux/arch/mips/jz4740/irq.c
Lars-Peter Clausen 9869848d12 MIPS: JZ4740: Add IRQ handler code
Add support for IRQ handling on a JZ4740 SoC.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/1465/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2010-08-05 13:26:13 +01:00

168 lines
3.9 KiB
C

/*
* Copyright (C) 2009-2010, Lars-Peter Clausen <lars@metafoo.de>
* JZ4740 platform IRQ support
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 675 Mass Ave, Cambridge, MA 02139, USA.
*
*/
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/interrupt.h>
#include <linux/ioport.h>
#include <linux/timex.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/debugfs.h>
#include <linux/seq_file.h>
#include <asm/io.h>
#include <asm/mipsregs.h>
#include <asm/irq_cpu.h>
#include <asm/mach-jz4740/base.h>
static void __iomem *jz_intc_base;
static uint32_t jz_intc_wakeup;
static uint32_t jz_intc_saved;
#define JZ_REG_INTC_STATUS 0x00
#define JZ_REG_INTC_MASK 0x04
#define JZ_REG_INTC_SET_MASK 0x08
#define JZ_REG_INTC_CLEAR_MASK 0x0c
#define JZ_REG_INTC_PENDING 0x10
#define IRQ_BIT(x) BIT((x) - JZ4740_IRQ_BASE)
static void intc_irq_unmask(unsigned int irq)
{
writel(IRQ_BIT(irq), jz_intc_base + JZ_REG_INTC_CLEAR_MASK);
}
static void intc_irq_mask(unsigned int irq)
{
writel(IRQ_BIT(irq), jz_intc_base + JZ_REG_INTC_SET_MASK);
}
static int intc_irq_set_wake(unsigned int irq, unsigned int on)
{
if (on)
jz_intc_wakeup |= IRQ_BIT(irq);
else
jz_intc_wakeup &= ~IRQ_BIT(irq);
return 0;
}
static struct irq_chip intc_irq_type = {
.name = "INTC",
.mask = intc_irq_mask,
.mask_ack = intc_irq_mask,
.unmask = intc_irq_unmask,
.set_wake = intc_irq_set_wake,
};
static irqreturn_t jz4740_cascade(int irq, void *data)
{
uint32_t irq_reg;
irq_reg = readl(jz_intc_base + JZ_REG_INTC_PENDING);
if (irq_reg)
generic_handle_irq(__fls(irq_reg) + JZ4740_IRQ_BASE);
return IRQ_HANDLED;
}
static struct irqaction jz4740_cascade_action = {
.handler = jz4740_cascade,
.name = "JZ4740 cascade interrupt",
};
void __init arch_init_irq(void)
{
int i;
mips_cpu_irq_init();
jz_intc_base = ioremap(JZ4740_INTC_BASE_ADDR, 0x14);
for (i = JZ4740_IRQ_BASE; i < JZ4740_IRQ_BASE + 32; i++) {
intc_irq_mask(i);
set_irq_chip_and_handler(i, &intc_irq_type, handle_level_irq);
}
setup_irq(2, &jz4740_cascade_action);
}
asmlinkage void plat_irq_dispatch(void)
{
unsigned int pending = read_c0_status() & read_c0_cause() & ST0_IM;
if (pending & STATUSF_IP2)
do_IRQ(2);
else if (pending & STATUSF_IP3)
do_IRQ(3);
else
spurious_interrupt();
}
void jz4740_intc_suspend(void)
{
jz_intc_saved = readl(jz_intc_base + JZ_REG_INTC_MASK);
writel(~jz_intc_wakeup, jz_intc_base + JZ_REG_INTC_SET_MASK);
writel(jz_intc_wakeup, jz_intc_base + JZ_REG_INTC_CLEAR_MASK);
}
void jz4740_intc_resume(void)
{
writel(~jz_intc_saved, jz_intc_base + JZ_REG_INTC_CLEAR_MASK);
writel(jz_intc_saved, jz_intc_base + JZ_REG_INTC_SET_MASK);
}
#ifdef CONFIG_DEBUG_FS
static inline void intc_seq_reg(struct seq_file *s, const char *name,
unsigned int reg)
{
seq_printf(s, "%s:\t\t%08x\n", name, readl(jz_intc_base + reg));
}
static int intc_regs_show(struct seq_file *s, void *unused)
{
intc_seq_reg(s, "Status", JZ_REG_INTC_STATUS);
intc_seq_reg(s, "Mask", JZ_REG_INTC_MASK);
intc_seq_reg(s, "Pending", JZ_REG_INTC_PENDING);
return 0;
}
static int intc_regs_open(struct inode *inode, struct file *file)
{
return single_open(file, intc_regs_show, NULL);
}
static const struct file_operations intc_regs_operations = {
.open = intc_regs_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static int __init intc_debugfs_init(void)
{
(void) debugfs_create_file("jz_regs_intc", S_IFREG | S_IRUGO,
NULL, NULL, &intc_regs_operations);
return 0;
}
subsys_initcall(intc_debugfs_init);
#endif