stage2/exceptions.c

   1 /*  exceptions.c - exception handling
   2
   3 Copyright (C) 2010-2011  Hector Martin "marcan" <hector@marcansoft.com>
   4
   5 This code is licensed to you under the terms of the GNU GPL, version 2;
   6 see file COPYING or http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt
   7 */
   8
   9 #include "types.h"
  10 #include "exceptions.h"
  11 #include "mm.h"
  12 #include "string.h"
  13 #include "debug.h"
  14 #include "lv1call.h"
  15
  16 extern u8 _exc_vec[], _exc_vec_end[];
  17
  18 struct exc_data *exc = (void*)0x2000;
  19
  20 static void print_exception(int exception)
  21 {
  22         int i;
  23
  24         u32 tid;
  25         asm("mfspr %0, 0x88" : "=r"(tid));
  26         tid = 2-(tid>>30);
  27         printf("\nException %04x occurred on thread %d!\n", exception, tid);
  28
  29         for (i=0; i<32; i+=4) {
  30                 printf("r%d-%d: ", i, i+3);
  31                 if (i<8) printf("  ");
  32                 if (i==8) printf(" ");
  33                 printf("%16lx %16lx %16lx %16lx\n", exc->regs[i], exc->regs[i+1], exc->regs[i+2], exc->regs[i+3]);
  34         }
  35
  36         printf("LR:    %016lx\n", exc->lr);
  37         printf("CTR:   %016lx\n", exc->ctr);
  38         printf("CR:    %08lx\n", exc->cr);
  39         printf("XER:   %08lx\n", exc->xer);
  40         printf("DAR:   %016lx\n", exc->dar);
  41         printf("DSISR: %08lx\n", exc->dsisr);
  42         printf("SRR0:  %016lx\n", exc->srr0);
  43         printf("SRR1:  %016lx\n", exc->srr1);
  44
  45 }
  46
  47 void exception_handler(int exception)
  48 {
  49         switch(exception) {
  50                 case 0x300: // Data Storage
  51                         if ((exc->dsisr & (1<<30)) && mm_loadhtab(exc->dar))
  52                                 return;
  53                         break;
  54                 case 0x380: // Data Segment
  55                         if (mm_loadseg(exc->dar))
  56                                 return;
  57                         break;
  58                 case 0x400: // Instruction Storage
  59                         if ((exc->srr1 & (1<<30)) && mm_loadhtab(exc->srr0))
  60                                 return;
  61                         break;
  62                 case 0x480: // Instruction Segment
  63                         if (mm_loadseg(exc->srr0))
  64                                 return;
  65                         break;
  66         }
  67         print_exception(exception);
  68         printf("\nUnhandled exception. Panicing...\n");
  69         lv1_panic(0);
  70         while(1);
  71 }
  72
  73 void exceptions_init(void)
  74 {
  75         u64 addr;
  76
  77         printf("Installing exception handlers...\n");
  78
  79         for (addr=0x100; addr<0x2000; addr+=0x20) {
  80                 u32 *p = (u32*)addr;
  81                 memcpy(p, _exc_vec, _exc_vec_end - _exc_vec);
  82                 p[6] |= addr; // patch exception number
  83                 sync_before_exec(p, 0x20);
  84         }
  85 }