arch/mips/kernel/irq-rm7000.c

   1 /*
   2  * Copyright (C) 2003 Ralf Baechle
   3  *
   4  * This program is free software; you can redistribute  it and/or modify it
   5  * under  the terms of  the GNU General  Public License as published by the
   6  * Free Software Foundation;  either version 2 of the  License, or (at your
   7  * option) any later version.
   8  *
   9  * Handler for RM7000 extended interrupts.  These are a non-standard
  10  * feature so we handle them separately from standard interrupts.
  11  */
  12 #include <linux/init.h>
  13 #include <linux/interrupt.h>
  14 #include <linux/kernel.h>
  15
  16 #include <asm/irq_cpu.h>
  17 #include <asm/mipsregs.h>
  18 #include <asm/system.h>
  19
  20 static int irq_base;
  21
  22 static inline void unmask_rm7k_irq(unsigned int irq)
  23 {
  24         set_c0_intcontrol(0x100 << (irq - irq_base));
  25 }
  26
  27 static inline void mask_rm7k_irq(unsigned int irq)
  28 {
  29         clear_c0_intcontrol(0x100 << (irq - irq_base));
  30 }
  31
  32 static void rm7k_cpu_irq_end(unsigned int irq)
  33 {
  34         if (!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS)))
  35                 unmask_rm7k_irq(irq);
  36 }
  37
  38 static struct irq_chip rm7k_irq_controller = {
  39         .typename = "RM7000",
  40         .ack = mask_rm7k_irq,
  41         .mask = mask_rm7k_irq,
  42         .mask_ack = mask_rm7k_irq,
  43         .unmask = unmask_rm7k_irq,
  44         .end = rm7k_cpu_irq_end,
  45 };
  46
  47 void __init rm7k_cpu_irq_init(int base)
  48 {
  49         int i;
  50
  51         clear_c0_intcontrol(0x00000f00);                /* Mask all */
  52
  53         for (i = base; i < base + 4; i++)
  54                 set_irq_chip(i, &rm7k_irq_controller);
  55
  56         irq_base = base;
  57 }