diff options
Diffstat (limited to 'arch/mips/cobalt/irq.c')
-rw-r--r-- | arch/mips/cobalt/irq.c | 102 |
1 files changed, 102 insertions, 0 deletions
diff --git a/arch/mips/cobalt/irq.c b/arch/mips/cobalt/irq.c new file mode 100644 index 0000000..6d2a815 --- /dev/null +++ b/arch/mips/cobalt/irq.c @@ -0,0 +1,102 @@ +/* + * 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); +} |