- 根目录:
- arch
- unicore32
- kernel
- irq.c
/*
* linux/arch/unicore32/kernel/irq.c
*
* Code specific to PKUnity SoC and UniCore ISA
*
* Copyright (C) 2001-2010 GUAN Xue-tao
*
* 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/kernel_stat.h>
#include <linux/module.h>
#include <linux/signal.h>
#include <linux/ioport.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/random.h>
#include <linux/smp.h>
#include <linux/init.h>
#include <linux/seq_file.h>
#include <linux/errno.h>
#include <linux/list.h>
#include <linux/kallsyms.h>
#include <linux/proc_fs.h>
#include <linux/syscore_ops.h>
#include <linux/gpio.h>
#include <mach/hardware.h>
#include "setup.h"
/*
* PKUnity GPIO edge detection for IRQs:
* IRQs are generated on Falling-Edge, Rising-Edge, or both.
* Use this instead of directly setting GRER/GFER.
*/
static int GPIO_IRQ_rising_edge;
static int GPIO_IRQ_falling_edge;
static int GPIO_IRQ_mask = 0;
#define GPIO_MASK(irq) (1 << (irq - IRQ_GPIO0))
static int puv3_gpio_type(struct irq_data *d, unsigned int type)
{
unsigned int mask;
if (d->irq < IRQ_GPIOHIGH)
mask = 1 << d->irq;
else
mask = GPIO_MASK(d->irq);
if (type == IRQ_TYPE_PROBE) {
if ((GPIO_IRQ_rising_edge | GPIO_IRQ_falling_edge) & mask)
return 0;
type = IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING;
}
if (type & IRQ_TYPE_EDGE_RISING)
GPIO_IRQ_rising_edge |= mask;
else
GPIO_IRQ_rising_edge &= ~mask;
if (type & IRQ_TYPE_EDGE_FALLING)
GPIO_IRQ_falling_edge |= mask;
else
GPIO_IRQ_falling_edge &= ~mask;
writel(GPIO_IRQ_rising_edge & GPIO_IRQ_mask, GPIO_GRER);
writel(GPIO_IRQ_falling_edge & GPIO_IRQ_mask, GPIO_GFER);
return 0;
}
/*
* GPIO IRQs must be acknowledged. This is for IRQs from 0 to 7.
*/
static void puv3_low_gpio_ack(struct irq_data *d)
{
writel((1 << d->irq), GPIO_GEDR);
}
static void puv3_low_gpio_mask(struct irq_data *d)
{
writel(readl(INTC_ICMR) & ~(1 << d->irq), INTC_ICMR);
}
static void puv3_low_gpio_unmask(struct irq_data *d)
{
writel(readl(INTC_ICMR) | (1 << d->irq), INTC_ICMR);
}
static int puv3_low_gpio_wake(struct irq_data *d, unsigned int on)
{
if (on)
writel(readl(PM_PWER) | (1 << d->irq), PM_PWER);
else
writel(readl(PM_PWER) & ~(1 << d->irq), PM_PWER);
return 0;
}
static struct irq_chip puv3_low_gpio_chip = {
.name = "GPIO-low",
.irq_ack = puv3_low_gpio_ack,
.irq_mask = puv3_low_gpio_mask,
.irq_unmask = puv3_low_gpio_unmask,
.irq_set_type = puv3_gpio_type,
.irq_set_wake = puv3_low_gpio_wake,
};
/*
* IRQ8 (GPIO0 through 27) handler. We enter here with the
* irq_controller_lock held, and IRQs disabled. Decode the IRQ
* and call the handler.
*/
static void
puv3_gpio_handler(unsigned int irq, struct irq_desc *desc)
{
unsigned int mask;
mask = readl(GPIO_GEDR);
do {
/*
* clear down all currently active IRQ sources.
* We will be processing them all.
*/
writel(mask, GPIO_GEDR);
irq = IRQ_GPIO0;
do {
if (mask & 1)
generic_handle_irq(irq);
mask >>= 1;
irq++;
} while (mask);
mask = readl(GPIO_GEDR);
} while (mask);
}
/*
* GPIO0-27 edge IRQs need to be handled specially.
* In addition, the IRQs are all collected up into one bit in the
* interrupt controller registers.
*/
static void puv3_high_gpio_ack(struct irq_data *d)
{
unsigned int mask = GPIO_MASK(d->irq);
writel(mask, GPIO_GEDR);
}
static void puv3_high_gpio_mask(struct irq_data *d)
{
unsigned int mask = GPIO_MASK(d->irq);
GPIO_IRQ_mask &= ~mask;
writel(readl(GPIO_GRER) & ~mask, GPIO_GRER);
writel(readl(GPIO_GFER) & ~mask, GPIO_GFER);
}
static void puv3_high_gpio_unmask(struct irq_data *d)
{
unsigned int mask = GPIO_MASK(d->irq);
GPIO_IRQ_mask |= mask;
writel(GPIO_IRQ_rising_edge & GPIO_IRQ_mask, GPIO_GRER);
writel(GPIO_IRQ_falling_edge & GPIO_IRQ_mask, GPIO_GFER);
}
static int puv3_high_gpio_wake(struct irq_data *d, unsigned int on)
{
if (on)
writel(readl(PM_PWER) | PM_PWER_GPIOHIGH, PM_PWER);
else
writel(readl(PM_PWER) & ~PM_PWER_GPIOHIGH, PM_PWER);
return 0;
}
static struct irq_chip puv3_high_gpio_chip = {
.name = "GPIO-high",
.irq_ack = puv3_high_gpio_ack,
.irq_mask = puv3_high_gpio_mask,
.irq_unmask = puv3_high_gpio_unmask,
.irq_set_type = puv3_gpio_type,
.irq_set_wake = puv3_high_gpio_wake,
};
/*
* We don't need to ACK IRQs on the PKUnity unless they're GPIOs
* this is for internal IRQs i.e. from 8 to 31.
*/
static void puv3_mask_irq(struct irq_data *d)
{
writel(readl(INTC_ICMR) & ~(1 << d->irq), INTC_ICMR);
}
static void puv3_unmask_irq(struct irq_data *d)
{
writel(readl(INTC_ICMR) | (1 << d->irq), INTC_ICMR);
}
/*
* Apart form GPIOs, only the RTC alarm can be a wakeup event.
*/
static int puv3_set_wake(struct irq_data *d, unsigned int on)
{
if (d->irq == IRQ_RTCAlarm) {
if (on)
writel(readl(PM_PWER) | PM_PWER_RTC, PM_PWER);
else
writel(readl(PM_PWER) & ~PM_PWER_RTC, PM_PWER);
return 0;
}
return -EINVAL;
}
static struct irq_chip puv3_normal_chip = {
.name = "PKUnity-v3",
.irq_ack = puv3_mask_irq,
.irq_mask = puv3_mask_irq,
.irq_unmask = puv3_unmask_irq,
.irq_set_wake = puv3_set_wake,
};
static struct resource irq_resource = {
.name = "irqs",
.start = io_v2p(PKUNITY_INTC_BASE),
.end = io_v2p(PKUNITY_INTC_BASE) + 0xFFFFF,
};
static struct puv3_irq_state {
unsigned int saved;
unsigned int icmr;
unsigned int iclr;
unsigned int iccr;
} puv3_irq_state;
static int puv3_irq_suspend(void)
{
struct puv3_irq_state *st = &puv3_irq_state;
st->saved = 1;
st->icmr = readl(INTC_ICMR);
st->iclr = readl(INTC_ICLR);
st->iccr = readl(INTC_ICCR);
/*
* Disable all GPIO-based interrupts.
*/
writel(readl(INTC_ICMR) & ~(0x1ff), INTC_ICMR);
/*
* Set the appropriate edges for wakeup.
*/
writel(readl(PM_PWER) & GPIO_IRQ_rising_edge, GPIO_GRER);
writel(readl(PM_PWER) & GPIO_IRQ_falling_edge, GPIO_GFER);
/*
* Clear any pending GPIO interrupts.
*/
writel(readl(GPIO_GEDR), GPIO_GEDR);
return 0;
}
static void puv3_irq_resume(void)
{
struct puv3_irq_state *st = &puv3_irq_state;
if (st->saved) {
writel(st->iccr, INTC_ICCR);
writel(st->iclr, INTC_ICLR);
writel(GPIO_IRQ_rising_edge & GPIO_IRQ_mask, GPIO_GRER);
writel(GPIO_IRQ_falling_edge & GPIO_IRQ_mask, GPIO_GFER);
writel(st->icmr, INTC_ICMR);
}
}
static struct syscore_ops puv3_irq_syscore_ops = {
.suspend = puv3_irq_suspend,
.resume = puv3_irq_resume,
};
static int __init puv3_irq_init_syscore(void)
{
register_syscore_ops(&puv3_irq_syscore_ops);
return 0;
}
device_initcall(puv3_irq_init_syscore);
void __init init_IRQ(void)
{
unsigned int irq;
request_resource(&iomem_resource, &irq_resource);
/* disable all IRQs */
writel(0, INTC_ICMR);
/* all IRQs are IRQ, not REAL */
writel(0, INTC_ICLR);
/* clear all GPIO edge detects */
writel(FMASK(8, 0) & ~FIELD(1, 1, GPI_SOFF_REQ), GPIO_GPIR);
writel(0, GPIO_GFER);
writel(0, GPIO_GRER);
writel(0x0FFFFFFF, GPIO_GEDR);
writel(1, INTC_ICCR);
for (irq = 0; irq < IRQ_GPIOHIGH; irq++) {
irq_set_chip(irq, &puv3_low_gpio_chip);
irq_set_handler(irq, handle_edge_irq);
irq_modify_status(irq,
IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN,
0);
}
for (irq = IRQ_GPIOHIGH + 1; irq < IRQ_GPIO0; irq++) {
irq_set_chip(irq, &puv3_normal_chip);
irq_set_handler(irq, handle_level_irq);
irq_modify_status(irq,
IRQ_NOREQUEST | IRQ_NOAUTOEN,
IRQ_NOPROBE);
}
for (irq = IRQ_GPIO0; irq <= IRQ_GPIO27; irq++) {
irq_set_chip(irq, &puv3_high_gpio_chip);
irq_set_handler(irq, handle_edge_irq);
irq_modify_status(irq,
IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN,
0);
}
/*
* Install handler for GPIO 0-27 edge detect interrupts
*/
irq_set_chip(IRQ_GPIOHIGH, &puv3_normal_chip);
irq_set_chained_handler(IRQ_GPIOHIGH, puv3_gpio_handler);
#ifdef CONFIG_PUV3_GPIO
puv3_init_gpio();
#endif
}
/*
* do_IRQ handles all hardware IRQ's. Decoded IRQs should not
* come via this function. Instead, they should provide their
* own 'handler'
*/
asmlinkage void asm_do_IRQ(unsigned int irq, struct pt_regs *regs)
{
struct pt_regs *old_regs = set_irq_regs(regs);
irq_enter();
/*
* Some hardware gives randomly wrong interrupts. Rather
* than crashing, do something sensible.
*/
if (unlikely(irq >= nr_irqs)) {
if (printk_ratelimit())
printk(KERN_WARNING "Bad IRQ%u\n", irq);
ack_bad_irq(irq);
} else {
generic_handle_irq(irq);
}
irq_exit();
set_irq_regs(old_regs);
}