release/src-rt-6.x.4708/linux/linux-2.6.36/arch/mips/cobalt/irq.c

   1 /*
   2  * IRQ vector handles
   3  *
   4  * This file is subject to the terms and conditions of the GNU General Public
   5  * License.  See the file "COPYING" in the main directory of this archive
   6  * for more details.
   7  *
   8  * Copyright (C) 1995, 1996, 1997, 2003 by Ralf Baechle
   9  */
  10 #include <linux/kernel.h>
  11 #include <linux/init.h>
  12 #include <linux/irq.h>
  13 #include <linux/interrupt.h>
  14 #include <linux/pci.h>
  15
  16 #include <asm/i8259.h>
  17 #include <asm/irq_cpu.h>
  18 #include <asm/irq_gt641xx.h>
  19 #include <asm/gt64120.h>
  20
  21 #include <irq.h>
  22
  23 asmlinkage void plat_irq_dispatch(void)
  24 {
  25         unsigned pending = read_c0_status() & read_c0_cause() & ST0_IM;
  26         int irq;
  27
  28         if (pending & CAUSEF_IP2)
  29                 gt641xx_irq_dispatch();
  30         else if (pending & CAUSEF_IP6) {
  31                 irq = i8259_irq();
  32                 if (irq < 0)
  33                         spurious_interrupt();
  34                 else
  35                         do_IRQ(irq);
  36         } else if (pending & CAUSEF_IP3)
  37                 do_IRQ(MIPS_CPU_IRQ_BASE + 3);
  38         else if (pending & CAUSEF_IP4)
  39                 do_IRQ(MIPS_CPU_IRQ_BASE + 4);
  40         else if (pending & CAUSEF_IP5)
  41                 do_IRQ(MIPS_CPU_IRQ_BASE + 5);
  42         else if (pending & CAUSEF_IP7)
  43                 do_IRQ(MIPS_CPU_IRQ_BASE + 7);
  44         else
  45                 spurious_interrupt();
  46 }
  47
  48 static struct irqaction cascade = {
  49         .handler        = no_action,
  50         .name           = "cascade",
  51 };
  52
  53 void __init arch_init_irq(void)
  54 {
  55         mips_cpu_irq_init();
  56         gt641xx_irq_init();
  57         init_i8259_irqs();
  58
  59         setup_irq(GT641XX_CASCADE_IRQ, &cascade);
  60         setup_irq(I8259_CASCADE_IRQ, &cascade);
  61 }