arch/cris/arch-v32/kernel/traps.c

   1 /*
   2  * Copyright (C) 2003-2006, Axis Communications AB.
   3  */
   4
   5 #include <linux/ptrace.h>
   6 #include <linux/module.h>
   7 #include <asm/uaccess.h>
   8 #include <hwregs/supp_reg.h>
   9 #include <hwregs/intr_vect_defs.h>
  10 #include <asm/irq.h>
  11
  12 void
  13 show_registers(struct pt_regs *regs)
  14 {
  15         /*
  16          * It's possible to use either the USP register or current->thread.usp.
  17          * USP might not correspond to the current process for all cases this
  18          * function is called, and current->thread.usp isn't up to date for the
  19          * current process. Experience shows that using USP is the way to go.
  20          */
  21         unsigned long usp = rdusp();
  22         unsigned long d_mmu_cause;
  23         unsigned long i_mmu_cause;
  24
  25         printk("CPU: %d\n", smp_processor_id());
  26
  27         printk("ERP: %08lx SRP: %08lx  CCS: %08lx USP: %08lx MOF: %08lx\n",
  28                regs->erp, regs->srp, regs->ccs, usp, regs->mof);
  29
  30         printk(" r0: %08lx  r1: %08lx   r2: %08lx  r3: %08lx\n",
  31                regs->r0, regs->r1, regs->r2, regs->r3);
  32
  33         printk(" r4: %08lx  r5: %08lx   r6: %08lx  r7: %08lx\n",
  34                regs->r4, regs->r5, regs->r6, regs->r7);
  35
  36         printk(" r8: %08lx  r9: %08lx  r10: %08lx r11: %08lx\n",
  37                regs->r8, regs->r9, regs->r10, regs->r11);
  38
  39         printk("r12: %08lx r13: %08lx oR10: %08lx acr: %08lx\n",
  40                regs->r12, regs->r13, regs->orig_r10, regs->acr);
  41
  42         printk(" sp: %08lx\n", (unsigned long)regs);
  43
  44         SUPP_BANK_SEL(BANK_IM);
  45         SUPP_REG_RD(RW_MM_CAUSE, i_mmu_cause);
  46
  47         SUPP_BANK_SEL(BANK_DM);
  48         SUPP_REG_RD(RW_MM_CAUSE, d_mmu_cause);
  49
  50         printk("       Data MMU Cause: %08lx\n", d_mmu_cause);
  51         printk("Instruction MMU Cause: %08lx\n", i_mmu_cause);
  52
  53         printk("Process %s (pid: %d, stackpage=%08lx)\n",
  54                current->comm, current->pid, (unsigned long)current);
  55
  56         /*
  57          * When in-kernel, we also print out the stack and code at the
  58          * time of the fault..
  59          */
  60         if (!user_mode(regs)) {
  61                 int i;
  62
  63                 show_stack(NULL, (unsigned long *)usp);
  64
  65                 /*
  66                  * If the previous stack-dump wasn't a kernel one, dump the
  67                  * kernel stack now.
  68                  */
  69                 if (usp != 0)
  70                         show_stack(NULL, NULL);
  71
  72                 printk("\nCode: ");
  73
  74                 if (regs->erp < PAGE_OFFSET)
  75                         goto bad_value;
  76
  77                 /*
  78                  * Quite often the value at regs->erp doesn't point to the
  79                  * interesting instruction, which often is the previous
  80                  * instruction. So dump at an offset large enough that the
  81                  * instruction decoding should be in sync at the interesting
  82                  * point, but small enough to fit on a row. The regs->erp
  83                  * location is pointed out in a ksymoops-friendly way by
  84                  * wrapping the byte for that address in parenthesises.
  85                  */
  86                 for (i = -12; i < 12; i++) {
  87                         unsigned char c;
  88
  89                         if (__get_user(c, &((unsigned char *)regs->erp)[i])) {
  90 bad_value:
  91                                 printk(" Bad IP value.");
  92                                 break;
  93                         }
  94
  95                         if (i == 0)
  96                                 printk("(%02x) ", c);
  97                         else
  98                                 printk("%02x ", c);
  99                 }
 100                 printk("\n");
 101         }
 102 }
 103
 104 void
 105 arch_enable_nmi(void)
 106 {
 107         unsigned long flags;
 108
 109         local_save_flags(flags);
 110         flags |= (1 << 30); /* NMI M flag is at bit 30 */
 111         local_irq_restore(flags);
 112 }
 113
 114 extern void (*nmi_handler)(struct pt_regs *);
 115 void handle_nmi(struct pt_regs *regs)
 116 {
 117 #ifdef CONFIG_ETRAXFS
 118         reg_intr_vect_r_nmi r;
 119 #endif
 120
 121         if (nmi_handler)
 122                 nmi_handler(regs);
 123
 124 #ifdef CONFIG_ETRAXFS
 125         /* Wait until nmi is no longer active. */
 126         do {
 127                 r = REG_RD(intr_vect, regi_irq, r_nmi);
 128         } while (r.ext == regk_intr_vect_on);
 129 #endif
 130 }
 131
 132
 133 #ifdef CONFIG_BUG
 134 extern void die_if_kernel(const char *str, struct pt_regs *regs, long err);
 135
 136 /* Copy of the regs at BUG() time.  */
 137 struct pt_regs BUG_regs;
 138
 139 void do_BUG(char *file, unsigned int line)
 140 {
 141         printk("kernel BUG at %s:%d!\n", file, line);
 142         die_if_kernel("Oops", &BUG_regs, 0);
 143 }
 144 EXPORT_SYMBOL(do_BUG);
 145
 146 void fixup_BUG(struct pt_regs *regs)
 147 {
 148         BUG_regs = *regs;
 149
 150 #ifdef CONFIG_DEBUG_BUGVERBOSE
 151         /*
 152          * Fixup the BUG arguments through exception handlers.
 153          */
 154         {
 155                 const struct exception_table_entry *fixup;
 156
 157                 /*
 158                  * ERP points at the "break 14" + 2, compensate for the 2
 159                  * bytes.
 160                  */
 161                 fixup = search_exception_tables(instruction_pointer(regs) - 2);
 162                 if (fixup) {
 163                         /* Adjust the instruction pointer in the stackframe. */
 164                         instruction_pointer(regs) = fixup->fixup;
 165                         arch_fixup(regs);
 166                 }
 167         }
 168 #else
 169         /* Dont try to lookup the filename + line, just dump regs.  */
 170         do_BUG("unknown", 0);
 171 #endif
 172 }
 173
 174 /*
 175  * Break 14 handler. Save regs and jump into the fixup_BUG.
 176  */
 177 __asm__  ( ".text\n\t"
 178            ".global breakh_BUG\n\t"
 179            "breakh_BUG:\n\t"
 180            SAVE_ALL
 181            KGDB_FIXUP
 182            "move.d $sp, $r10\n\t"
 183            "jsr fixup_BUG\n\t"
 184            "nop\n\t"
 185            "jump ret_from_intr\n\t"
 186            "nop\n\t");
 187
 188
 189 #ifdef CONFIG_DEBUG_BUGVERBOSE
 190 void
 191 handle_BUG(struct pt_regs *regs)
 192 {
 193 }
 194 #endif
 195 #endif