linux/arch/mips/cobalt/irq.c
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00

103 lines
2.3 KiB
C

/*
* IRQ vector handles
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 1995, 1996, 1997, 2003 by Ralf Baechle
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/irq.h>
#include <asm/i8259.h>
#include <asm/irq_cpu.h>
#include <asm/gt64120.h>
#include <asm/ptrace.h>
#include <asm/cobalt/cobalt.h>
extern void cobalt_handle_int(void);
/*
* We have two types of interrupts that we handle, ones that come in through
* the CPU interrupt lines, and ones that come in on the via chip. The CPU
* mappings are:
*
* 16, - Software interrupt 0 (unused) IE_SW0
* 17 - Software interrupt 1 (unused) IE_SW0
* 18 - Galileo chip (timer) IE_IRQ0
* 19 - Tulip 0 + NCR SCSI IE_IRQ1
* 20 - Tulip 1 IE_IRQ2
* 21 - 16550 UART IE_IRQ3
* 22 - VIA southbridge PIC IE_IRQ4
* 23 - unused IE_IRQ5
*
* The VIA chip is a master/slave 8259 setup and has the following interrupts:
*
* 8 - RTC
* 9 - PCI
* 14 - IDE0
* 15 - IDE1
*/
asmlinkage void cobalt_irq(struct pt_regs *regs)
{
unsigned int pending = read_c0_status() & read_c0_cause();
if (pending & CAUSEF_IP2) { /* int 18 */
unsigned long irq_src = GALILEO_INL(GT_INTRCAUSE_OFS);
/* Check for timer irq ... */
if (irq_src & GALILEO_T0EXP) {
/* Clear the int line */
GALILEO_OUTL(0, GT_INTRCAUSE_OFS);
do_IRQ(COBALT_TIMER_IRQ, regs);
}
return;
}
if (pending & CAUSEF_IP6) { /* int 22 */
int irq = i8259_irq();
if (irq >= 0)
do_IRQ(irq, regs);
return;
}
if (pending & CAUSEF_IP3) { /* int 19 */
do_IRQ(COBALT_ETH0_IRQ, regs);
return;
}
if (pending & CAUSEF_IP4) { /* int 20 */
do_IRQ(COBALT_ETH1_IRQ, regs);
return;
}
if (pending & CAUSEF_IP5) { /* int 21 */
do_IRQ(COBALT_SERIAL_IRQ, regs);
return;
}
if (pending & CAUSEF_IP7) { /* int 23 */
do_IRQ(COBALT_QUBE_SLOT_IRQ, regs);
return;
}
}
void __init arch_init_irq(void)
{
set_except_vector(0, cobalt_handle_int);
init_i8259_irqs(); /* 0 ... 15 */
mips_cpu_irq_init(16); /* 16 ... 23 */
/*
* Mask all cpu interrupts
* (except IE4, we already masked those at VIA level)
*/
change_c0_status(ST0_IM, IE_IRQ4);
}