openwrt/target/linux/ar7-2.6/files/arch/mips/ar7/irq.c

161 lines
4.1 KiB
C

/*
* $Id$
*
* Copyright (C) 2006, 2007 OpenWrt.org
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/ioport.h>
#include <asm/irq.h>
#include <asm/irq_cpu.h>
#include <asm/mipsregs.h>
#include <asm/ar7/ar7.h>
#define EXCEPT_OFFSET 0x80
#define PACE_OFFSET 0xA0
#define CHNLS_OFFSET 0x200
#define IRQ_NUM(irq) (irq % 40 % 32)
#define REG_OFFSET(irq, reg) (((irq) < 40) ? \
((irq) / 32 * 0x4 + reg * 0x10) : \
(EXCEPT_OFFSET + reg * 0x8))
#define SR_OFFSET(irq) (REG_OFFSET(irq, 0))
#define CR_OFFSET(irq) (REG_OFFSET(irq, 1))
#define ESR_OFFSET(irq) (REG_OFFSET(irq, 2))
#define ECR_OFFSET(irq) (REG_OFFSET(irq, 3))
#define PIR_OFFSET (0x40)
#define MSR_OFFSET (0x44)
#define PM_OFFSET(irq) (REG_OFFSET(irq, 5))
#define TM_OFFSET(irq) (REG_OFFSET(irq, 6))
#define REG(addr) (*(volatile u32 *)(KSEG1ADDR(AR7_REGS_IRQ) + addr))
#define CHNL_OFFSET(chnl) (CHNLS_OFFSET + (chnl * 4))
static void ar7_unmask_irq(unsigned int irq_nr);
static void ar7_mask_irq(unsigned int irq_nr);
static irqreturn_t ar7_cascade(int interrupt, void *dev);
void ar7_irq_init(int);
static struct irq_chip ar7_irq_type = {
.name = "AR7",
.unmask = ar7_unmask_irq,
.mask = ar7_mask_irq,
};
static int ar7_irq_base;
static struct irqaction ar7_cascade_action = {
.handler = ar7_cascade,
.name = "AR7 cascade interrupt"
};
static void ar7_unmask_irq(unsigned int irq)
{
unsigned long flags;
local_irq_save(flags);
/* enable the interrupt channel bit */
REG(ESR_OFFSET(irq - ar7_irq_base)) = 1 << IRQ_NUM(irq - ar7_irq_base);
local_irq_restore(flags);
}
static void ar7_mask_irq(unsigned int irq)
{
unsigned long flags;
local_irq_save(flags);
/* disable the interrupt channel bit */
REG(ECR_OFFSET(irq - ar7_irq_base)) = 1 << IRQ_NUM(irq - ar7_irq_base);
local_irq_restore(flags);
}
void __init arch_init_irq(void) {
mips_cpu_irq_init(0);
ar7_irq_init(8);
}
void __init ar7_irq_init(int base)
{
int i;
/*
Disable interrupts and clear pending
*/
REG(ECR_OFFSET(0)) = 0xffffffff;
REG(ECR_OFFSET(32)) = 0xff;
REG(ECR_OFFSET(40)) = 0xffffffff;
REG(CR_OFFSET(0)) = 0xffffffff;
REG(CR_OFFSET(32)) = 0xff;
REG(CR_OFFSET(40)) = 0xffffffff;
for(i = 0; i < 40; i++) {
REG(CHNL_OFFSET(i)) = i;
/* Primary IRQ's */
irq_desc[i + base].status = IRQ_DISABLED;
irq_desc[i + base].action = 0;
irq_desc[i + base].depth = 1;
irq_desc[i + base].chip = &ar7_irq_type;
/* Secondary IRQ's */
if (i < 32) {
irq_desc[i + base + 40].status = IRQ_DISABLED;
irq_desc[i + base + 40].action = 0;
irq_desc[i + base + 40].depth = 1;
irq_desc[i + base + 40].chip =
&ar7_irq_type;
}
}
ar7_irq_base = base;
setup_irq(2, &ar7_cascade_action);
set_c0_status(IE_IRQ0);
}
static irqreturn_t ar7_cascade(int interrupt, void *dev)
{
int irq, i;
unsigned long status;
irq = (REG(PIR_OFFSET) & 0x3F);
if (irq == 40) return IRQ_NONE;
if (irq > 0) {
REG(CR_OFFSET(irq)) = 1 << IRQ_NUM(irq);
} else {
status = REG(SR_OFFSET(40));
for (i = 0; i < 32; i++) {
if (status & (i << 1)) {
irq = i + 40;
REG(CR_OFFSET(irq)) = 1 << i;
break;
}
}
REG(CR_OFFSET(0)) = 1;
}
return do_IRQ(irq + ar7_irq_base);
}
asmlinkage void plat_irq_dispatch(void)
{
unsigned int pending = read_c0_status() & read_c0_cause();
if (pending & STATUSF_IP7) /* cpu timer */
do_IRQ(7);
else if (pending & STATUSF_IP2) /* int0 hardware line */
do_IRQ(2);
else
spurious_interrupt();
}