arch/mips/kernel/irq-rm9000.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 RM9000 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/irq.h>
  15 #include <linux/kernel.h>
  16 #include <linux/module.h>
  17
  18 #include <asm/irq_cpu.h>
  19 #include <asm/mipsregs.h>
  20 #include <asm/system.h>
  21
  22 static inline void unmask_rm9k_irq(unsigned int irq)
  23 {
  24         set_c0_intcontrol(0x1000 << (irq - RM9K_CPU_IRQ_BASE));
  25 }
  26
  27 static inline void mask_rm9k_irq(unsigned int irq)
  28 {
  29         clear_c0_intcontrol(0x1000 << (irq - RM9K_CPU_IRQ_BASE));
  30 }
  31
  32 static inline void rm9k_cpu_irq_enable(unsigned int irq)
  33 {
  34         unsigned long flags;
  35
  36         local_irq_save(flags);
  37         unmask_rm9k_irq(irq);
  38         local_irq_restore(flags);
  39 }
  40
  41 /*
  42  * Performance counter interrupts are global on all processors.
  43  */
  44 static void local_rm9k_perfcounter_irq_startup(void *args)
  45 {
  46         unsigned int irq = (unsigned int) args;
  47
  48         rm9k_cpu_irq_enable(irq);
  49 }
  50
  51 static unsigned int rm9k_perfcounter_irq_startup(unsigned int irq)
  52 {
  53         on_each_cpu(local_rm9k_perfcounter_irq_startup, (void *) irq, 1);
  54
  55         return 0;
  56 }
  57
  58 static void local_rm9k_perfcounter_irq_shutdown(void *args)
  59 {
  60         unsigned int irq = (unsigned int) args;
  61         unsigned long flags;
  62
  63         local_irq_save(flags);
  64         mask_rm9k_irq(irq);
  65         local_irq_restore(flags);
  66 }
  67
  68 static void rm9k_perfcounter_irq_shutdown(unsigned int irq)
  69 {
  70         on_each_cpu(local_rm9k_perfcounter_irq_shutdown, (void *) irq, 1);
  71 }
  72
  73 static struct irq_chip rm9k_irq_controller = {
  74         .name = "RM9000",
  75         .ack = mask_rm9k_irq,
  76         .mask = mask_rm9k_irq,
  77         .mask_ack = mask_rm9k_irq,
  78         .unmask = unmask_rm9k_irq,
  79         .eoi    = unmask_rm9k_irq
  80 };
  81
  82 static struct irq_chip rm9k_perfcounter_irq = {
  83         .name = "RM9000",
  84         .startup = rm9k_perfcounter_irq_startup,
  85         .shutdown = rm9k_perfcounter_irq_shutdown,
  86         .ack = mask_rm9k_irq,
  87         .mask = mask_rm9k_irq,
  88         .mask_ack = mask_rm9k_irq,
  89         .unmask = unmask_rm9k_irq,
  90 };
  91
  92 unsigned int rm9000_perfcount_irq;
  93
  94 EXPORT_SYMBOL(rm9000_perfcount_irq);
  95
  96 void __init rm9k_cpu_irq_init(void)
  97 {
  98         int base = RM9K_CPU_IRQ_BASE;
  99         int i;
 100
 101         clear_c0_intcontrol(0x0000f000);                /* Mask all */
 102
 103         for (i = base; i < base + 4; i++)
 104                 set_irq_chip_and_handler(i, &rm9k_irq_controller,
 105                                          handle_level_irq);
 106
 107         rm9000_perfcount_irq = base + 1;
 108         set_irq_chip_and_handler(rm9000_perfcount_irq, &rm9k_perfcounter_irq,
 109                                  handle_percpu_irq);
 110 }