firmware/target/arm/system-arm.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright (C) 2006 by Thom Johansen
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License
  14  * as published by the Free Software Foundation; either version 2
  15  * of the License, or (at your option) any later version.
  16  *
  17  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  18  * KIND, either express or implied.
  19  *
  20  ****************************************************************************/
  21 #include "config.h"
  22 #include "system.h"
  23 #include <stdio.h>
  24 #include "lcd.h"
  25 #include "font.h"
  26
  27 static const char* const uiename[] = {
  28     "Undefined instruction",
  29     "Prefetch abort",
  30     "Data abort",
  31     "Divide by zero"
  32 };
  33
  34 /* Unexpected Interrupt or Exception handler. Currently only deals with
  35    exceptions, but will deal with interrupts later.
  36  */
  37 void __attribute__((noreturn)) UIE(unsigned int pc, unsigned int num)
  38 {
  39 #if LCD_DEPTH > 1
  40     lcd_set_backdrop(NULL);
  41     lcd_set_drawmode(DRMODE_SOLID);
  42     lcd_set_foreground(LCD_BLACK);
  43     lcd_set_background(LCD_WHITE);
  44 #endif
  45     unsigned line = 0;
  46
  47     lcd_setfont(FONT_SYSFIXED);
  48     lcd_set_viewport(NULL);
  49     lcd_clear_display();
  50     lcd_puts(0, line++, uiename[num]);
  51     lcd_putsf(0, line++, "at %08x" IF_COP(" (%d)"), pc
  52              IF_COP(, CURRENT_CORE));
  53
  54 #if !defined(CPU_ARM7TDMI) /* arm7tdmi has no MPU/MMU */
  55     if(num == 1 || num == 2) /* prefetch / data abort */
  56     {
  57         register unsigned status;
  58
  59 #if ARM_ARCH >= 6
  60         /* ARMv6 has 2 different registers for prefetch & data aborts */
  61         if(num == 1)    /* instruction prefetch abort */
  62             asm volatile( "mrc p15, 0, %0, c5, c0, 1\n" : "=r"(status));
  63         else
  64 #endif
  65             asm volatile( "mrc p15, 0, %0, c5, c0, 0\n" : "=r"(status));
  66
  67         lcd_putsf(0, line++, "FSR 0x%x", status);
  68
  69         unsigned int domain = (status >> 4) & 0xf;
  70         unsigned int fault = status & 0xf;
  71 #if ARM_ARCH >= 6
  72         fault |= (status & (1<<10)) >> 6; /* fault is 5 bits on armv6 */
  73 #endif
  74         lcd_putsf(0, line++, "(domain %d, fault %d)", domain, fault);
  75
  76         if(num == 2) /* data abort */
  77         {
  78             register unsigned address;
  79             /* read FAR (fault address register) */
  80             asm volatile( "mrc p15, 0, %0, c6, c0\n" : "=r"(address));
  81             lcd_putsf(0, line++, "address 0x%8x", address);
  82 #if ARM_ARCH >= 6
  83             lcd_putsf(0, line++, (status & (1<<11)) ? "(write)" : "(read)");
  84 #endif
  85         }
  86     }   /* num == 1 || num == 2 // prefetch/data abort */
  87 #endif /* !defined(CPU_ARM7TDMI */
  88
  89     lcd_update();
  90
  91     disable_interrupt(IRQ_FIQ_STATUS);
  92
  93     system_exception_wait(); /* If this returns, try to reboot */
  94     system_reboot();
  95     while (1);       /* halt */
  96 }
  97
  98 /* Needs to be here or gcc won't find it */
  99 void __attribute__((naked)) __div0(void)
 100 {
 101     asm volatile (
 102         "ldr    r0, [sp]    \r\n"
 103         "sub    r0, r0, #4  \r\n"
 104         "mov    r1, #3      \r\n"
 105         "b      UIE         \r\n"
 106     );
 107 }