arch/cris/arch-v10/kernel/traps.c

   1 /* $Id: traps.c,v 1.2 2003/07/04 08:27:41 starvik Exp $
   2  *
   3  *  linux/arch/cris/arch-v10/traps.c
   4  *
   5  *  Heler functions for trap handlers
   6  *
   7  *  Copyright (C) 2000-2002 Axis Communications AB
   8  *
   9  *  Authors:   Bjorn Wesen
  10  *             Hans-Peter Nilsson
  11  *
  12  */
  13
  14 #include <linux/config.h>
  15 #include <linux/ptrace.h>
  16 #include <asm/uaccess.h>
  17 #include <asm/arch/sv_addr_ag.h>
  18
  19 void
  20 show_registers(struct pt_regs * regs)
  21 {
  22         /* We either use rdusp() - the USP register, which might not
  23            correspond to the current process for all cases we're called,
  24            or we use the current->thread.usp, which is not up to date for
  25            the current process.  Experience shows we want the USP
  26            register.  */
  27         unsigned long usp = rdusp();
  28
  29         printk("IRP: %08lx SRP: %08lx DCCR: %08lx USP: %08lx MOF: %08lx\n",
  30                regs->irp, regs->srp, regs->dccr, usp, regs->mof );
  31         printk(" r0: %08lx  r1: %08lx   r2: %08lx  r3: %08lx\n",
  32                regs->r0, regs->r1, regs->r2, regs->r3);
  33         printk(" r4: %08lx  r5: %08lx   r6: %08lx  r7: %08lx\n",
  34                regs->r4, regs->r5, regs->r6, regs->r7);
  35         printk(" r8: %08lx  r9: %08lx  r10: %08lx r11: %08lx\n",
  36                regs->r8, regs->r9, regs->r10, regs->r11);
  37         printk("r12: %08lx r13: %08lx oR10: %08lx\n",
  38                regs->r12, regs->r13, regs->orig_r10);
  39         printk("R_MMU_CAUSE: %08lx\n", (unsigned long)*R_MMU_CAUSE);
  40         printk("Process %s (pid: %d, stackpage=%08lx)\n",
  41                current->comm, current->pid, (unsigned long)current);
  42
  43         /*
  44          * When in-kernel, we also print out the stack and code at the
  45          * time of the fault..
  46          */
  47         if (! user_mode(regs)) {
  48                 int i;
  49
  50                 show_stack(NULL, (unsigned long*)usp);
  51
  52                 /* Dump kernel stack if the previous dump wasn't one.  */
  53                 if (usp != 0)
  54                         show_stack (NULL, NULL);
  55
  56                 printk("\nCode: ");
  57                 if(regs->irp < PAGE_OFFSET)
  58                         goto bad;
  59
  60                 /* Often enough the value at regs->irp does not point to
  61                    the interesting instruction, which is most often the
  62                    _previous_ instruction.  So we dump at an offset large
  63                    enough that instruction decoding should be in sync at
  64                    the interesting point, but small enough to fit on a row
  65                    (sort of).  We point out the regs->irp location in a
  66                    ksymoops-friendly way by wrapping the byte for that
  67                    address in parentheses.  */
  68                 for(i = -12; i < 12; i++)
  69                 {
  70                         unsigned char c;
  71                         if(__get_user(c, &((unsigned char*)regs->irp)[i])) {
  72 bad:
  73                                 printk(" Bad IP value.");
  74                                 break;
  75                         }
  76
  77                         if (i == 0)
  78                           printk("(%02x) ", c);
  79                         else
  80                           printk("%02x ", c);
  81                 }
  82                 printk("\n");
  83         }
  84 }
  85
  86 /* Called from entry.S when the watchdog has bitten
  87  * We print out something resembling an oops dump, and if
  88  * we have the nice doggy development flag set, we halt here
  89  * instead of rebooting.
  90  */
  91
  92 extern void reset_watchdog(void);
  93 extern void stop_watchdog(void);
  94
  95
  96 void
  97 watchdog_bite_hook(struct pt_regs *regs)
  98 {
  99 #ifdef CONFIG_ETRAX_WATCHDOG_NICE_DOGGY
 100         local_irq_disable();
 101         stop_watchdog();
 102         show_registers(regs);
 103         while(1) /* nothing */;
 104 #else
 105         show_registers(regs);
 106 #endif
 107 }
 108
 109 /* This is normally the 'Oops' routine */
 110 void
 111 die_if_kernel(const char * str, struct pt_regs * regs, long err)
 112 {
 113         if(user_mode(regs))
 114                 return;
 115
 116 #ifdef CONFIG_ETRAX_WATCHDOG_NICE_DOGGY
 117         /* This printout might take too long and trigger the
 118          * watchdog normally. If we're in the nice doggy
 119          * development mode, stop the watchdog during printout.
 120          */
 121         stop_watchdog();
 122 #endif
 123
 124         printk("%s: %04lx\n", str, err & 0xffff);
 125
 126         show_registers(regs);
 127
 128 #ifdef CONFIG_ETRAX_WATCHDOG_NICE_DOGGY
 129         reset_watchdog();
 130 #endif
 131         do_exit(SIGSEGV);
 132 }