package/linux/kernel-source/arch/mips/brcm-boards/generic/irq.c

   1 /*
   2  * Generic interrupt control functions for Broadcom MIPS boards
   3  *
   4  * Copyright 2004, Broadcom Corporation
   5  * All Rights Reserved.
   6  *
   7  * THIS SOFTWARE IS OFFERED "AS IS", AND BROADCOM GRANTS NO WARRANTIES OF ANY
   8  * KIND, EXPRESS OR IMPLIED, BY STATUTE, COMMUNICATION OR OTHERWISE. BROADCOM
   9  * SPECIFICALLY DISCLAIMS ANY IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS
  10  * FOR A SPECIFIC PURPOSE OR NONINFRINGEMENT CONCERNING THIS SOFTWARE.
  11  *
  12  * $Id$
  13  */
  14
  15 #include <linux/config.h>
  16 #include <linux/init.h>
  17 #include <linux/kernel.h>
  18 #include <linux/types.h>
  19 #include <linux/interrupt.h>
  20 #include <linux/irq.h>
  21
  22 #include <asm/irq.h>
  23 #include <asm/mipsregs.h>
  24 #include <asm/gdb-stub.h>
  25
  26 #define ALLINTS (IE_IRQ0 | IE_IRQ1 | IE_IRQ2 | IE_IRQ3 | IE_IRQ4 | IE_IRQ5)
  27
  28 extern asmlinkage void brcmIRQ(void);
  29 extern asmlinkage unsigned int do_IRQ(int irq, struct pt_regs *regs);
  30
  31 void
  32 brcm_irq_dispatch(struct pt_regs *regs)
  33 {
  34         u32 cause;
  35
  36         cause = read_c0_cause() &
  37                 read_c0_status() &
  38                 CAUSEF_IP;
  39
  40 #ifdef CONFIG_KERNPROF
  41         change_c0_status(cause | 1, 1);
  42 #else
  43         clear_c0_status(cause);
  44 #endif
  45
  46         if (cause & CAUSEF_IP7)
  47                 do_IRQ(7, regs);
  48         if (cause & CAUSEF_IP2)
  49                 do_IRQ(2, regs);
  50         if (cause & CAUSEF_IP3)
  51                 do_IRQ(3, regs);
  52         if (cause & CAUSEF_IP4)
  53                 do_IRQ(4, regs);
  54         if (cause & CAUSEF_IP5)
  55                 do_IRQ(5, regs);
  56         if (cause & CAUSEF_IP6)
  57                 do_IRQ(6, regs);
  58 }
  59
  60 static void
  61 enable_brcm_irq(unsigned int irq)
  62 {
  63         if (irq < 8)
  64                 set_c0_status(1 << (irq + 8));
  65         else
  66                 set_c0_status(IE_IRQ0);
  67 }
  68
  69 static void
  70 disable_brcm_irq(unsigned int irq)
  71 {
  72         if (irq < 8)
  73                 clear_c0_status(1 << (irq + 8));
  74         else
  75                 clear_c0_status(IE_IRQ0);
  76 }
  77
  78 static void
  79 ack_brcm_irq(unsigned int irq)
  80 {
  81         /* Already done in brcm_irq_dispatch */
  82 }
  83
  84 static unsigned int
  85 startup_brcm_irq(unsigned int irq)
  86 {
  87         enable_brcm_irq(irq);
  88
  89         return 0; /* never anything pending */
  90 }
  91
  92 static void
  93 end_brcm_irq(unsigned int irq)
  94 {
  95         if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
  96                 enable_brcm_irq(irq);
  97 }
  98
  99 static struct hw_interrupt_type brcm_irq_type = {
 100         typename: "MIPS",
 101         startup: startup_brcm_irq,
 102         shutdown: disable_brcm_irq,
 103         enable: enable_brcm_irq,
 104         disable: disable_brcm_irq,
 105         ack: ack_brcm_irq,
 106         end: end_brcm_irq,
 107         NULL
 108 };
 109
 110 void __init
 111 init_IRQ(void)
 112 {
 113         int i;
 114
 115         for (i = 0; i < NR_IRQS; i++) {
 116                 irq_desc[i].status = IRQ_DISABLED;
 117                 irq_desc[i].action = 0;
 118                 irq_desc[i].depth = 1;
 119                 irq_desc[i].handler = &brcm_irq_type;
 120         }
 121
 122         set_except_vector(0, brcmIRQ);
 123         change_c0_status(ST0_IM, ALLINTS);
 124
 125 #ifdef CONFIG_REMOTE_DEBUG
 126         printk("Breaking into debugger...\n");
 127         set_debug_traps();
 128         breakpoint();
 129 #endif
 130 }