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