1 /* 2 * (C) Copyright 2000 3 * Wolfgang Denk, DENX Software Engineering, wd@denx.de. 4 * 5 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) 6 * 7 * This program is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU General Public License as 9 * published by the Free Software Foundation; either version 2 of 10 * the License, or (at your option) any later version. 11 * 12 * This program is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 * GNU General Public License for more details. 16 * 17 * You should have received a copy of the GNU General Public License 18 * along with this program; if not, write to the Free Software 19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, 20 * MA 02111-1307 USA 21 */ 22 23 /* 24 * This file handles the architecture-dependent parts of hardware 25 * exceptions 26 */ 27 28 #include <common.h> 29 #include <command.h> 30 #include <kgdb.h> 31 #include <asm/processor.h> 32 #include <asm/mpc8349_pci.h> 33 34 DECLARE_GLOBAL_DATA_PTR; 35 36 /* Returns 0 if exception not found and fixup otherwise. */ 37 extern unsigned long search_exception_table(unsigned long); 38 39 #define END_OF_MEM (gd->bd->bi_memstart + gd->bd->bi_memsize) 40 41 /* 42 * Trap & Exception support 43 */ 44 45 void 46 print_backtrace(unsigned long *sp) 47 { 48 int cnt = 0; 49 unsigned long i; 50 51 puts ("Call backtrace: "); 52 while (sp) { 53 if ((uint)sp > END_OF_MEM) 54 break; 55 56 i = sp[1]; 57 if (cnt++ % 7 == 0) 58 putc ('\n'); 59 printf("%08lX ", i); 60 if (cnt > 32) break; 61 sp = (unsigned long *)*sp; 62 } 63 putc ('\n'); 64 } 65 66 void show_regs(struct pt_regs * regs) 67 { 68 int i; 69 70 printf("NIP: %08lX XER: %08lX LR: %08lX REGS: %p TRAP: %04lx DAR: %08lX\n", 71 regs->nip, regs->xer, regs->link, regs, regs->trap, regs->dar); 72 printf("MSR: %08lx EE: %01x PR: %01x FP: %01x ME: %01x IR/DR: %01x%01x\n", 73 regs->msr, regs->msr&MSR_EE ? 1 : 0, regs->msr&MSR_PR ? 1 : 0, 74 regs->msr & MSR_FP ? 1 : 0,regs->msr&MSR_ME ? 1 : 0, 75 regs->msr&MSR_IR ? 1 : 0, 76 regs->msr&MSR_DR ? 1 : 0); 77 78 putc ('\n'); 79 for (i = 0; i < 32; i++) { 80 if ((i % 8) == 0) { 81 printf("GPR%02d: ", i); 82 } 83 84 printf("%08lX ", regs->gpr[i]); 85 if ((i % 8) == 7) { 86 putc ('\n'); 87 } 88 } 89 } 90 91 92 void 93 _exception(int signr, struct pt_regs *regs) 94 { 95 show_regs(regs); 96 print_backtrace((unsigned long *)regs->gpr[1]); 97 panic("Exception in kernel pc %lx signal %d",regs->nip,signr); 98 } 99 100 #ifdef CONFIG_PCI 101 void dump_pci (void) 102 { 103 /* 104 volatile immap_t *immap = (immap_t *) CONFIG_SYS_IMMR; 105 printf ("PCI: err status %x err mask %x err ctrl %x\n", 106 le32_to_cpu (immap->im_pci.pci_esr), 107 le32_to_cpu (immap->im_pci.pci_emr), 108 le32_to_cpu (immap->im_pci.pci_ecr)); 109 printf (" error address %x error data %x ctrl %x\n", 110 le32_to_cpu (immap->im_pci.pci_eacr), 111 le32_to_cpu (immap->im_pci.pci_edcr), 112 le32_to_cpu (immap->im_pci.pci_eccr)); 113 */ 114 } 115 #endif 116 117 void 118 MachineCheckException(struct pt_regs *regs) 119 { 120 unsigned long fixup; 121 122 /* Probing PCI using config cycles cause this exception 123 * when a device is not present. Catch it and return to 124 * the PCI exception handler. 125 */ 126 #ifdef CONFIG_PCI 127 #if 0 128 volatile immap_t *immap = (immap_t *)CONFIG_SYS_IMMR; 129 #ifdef DEBUG 130 dump_pci(); 131 #endif 132 /* clear the error in the error status register */ 133 if(immap->im_pci.pci_esr & cpu_to_le32(PCI_ERROR_PCI_NO_RSP)) { 134 immap->im_pci.pci_esr = cpu_to_le32(PCI_ERROR_PCI_NO_RSP); 135 return; 136 } 137 #endif 138 #endif /* CONFIG_PCI */ 139 if ((fixup = search_exception_table(regs->nip)) != 0) { 140 regs->nip = fixup; 141 return; 142 } 143 144 #if defined(CONFIG_CMD_KGDB) 145 if (debugger_exception_handler && (*debugger_exception_handler)(regs)) 146 return; 147 #endif 148 149 puts ("Machine check in kernel mode.\n" 150 "Caused by (from msr): "); 151 printf("regs %p ",regs); 152 switch( regs->msr & 0x000F0000) { 153 case (0x80000000>>12): 154 puts ("Machine check signal - probably due to mm fault\n" 155 "with mmu off\n"); 156 break; 157 case (0x80000000>>13): 158 puts ("Transfer error ack signal\n"); 159 break; 160 case (0x80000000>>14): 161 puts ("Data parity signal\n"); 162 break; 163 case (0x80000000>>15): 164 puts ("Address parity signal\n"); 165 break; 166 default: 167 puts ("Unknown values in msr\n"); 168 } 169 show_regs(regs); 170 print_backtrace((unsigned long *)regs->gpr[1]); 171 #ifdef CONFIG_PCI 172 dump_pci(); 173 #endif 174 panic("machine check"); 175 } 176 177 void 178 AlignmentException(struct pt_regs *regs) 179 { 180 #if defined(CONFIG_CMD_KGDB) 181 if (debugger_exception_handler && (*debugger_exception_handler)(regs)) 182 return; 183 #endif 184 show_regs(regs); 185 print_backtrace((unsigned long *)regs->gpr[1]); 186 panic("Alignment Exception"); 187 } 188 189 void 190 ProgramCheckException(struct pt_regs *regs) 191 { 192 #if defined(CONFIG_CMD_KGDB) 193 if (debugger_exception_handler && (*debugger_exception_handler)(regs)) 194 return; 195 #endif 196 show_regs(regs); 197 print_backtrace((unsigned long *)regs->gpr[1]); 198 panic("Program Check Exception"); 199 } 200 201 void 202 SoftEmuException(struct pt_regs *regs) 203 { 204 #if defined(CONFIG_CMD_KGDB) 205 if (debugger_exception_handler && (*debugger_exception_handler)(regs)) 206 return; 207 #endif 208 show_regs(regs); 209 print_backtrace((unsigned long *)regs->gpr[1]); 210 panic("Software Emulation Exception"); 211 } 212 213 214 void 215 UnknownException(struct pt_regs *regs) 216 { 217 #if defined(CONFIG_CMD_KGDB) 218 if (debugger_exception_handler && (*debugger_exception_handler)(regs)) 219 return; 220 #endif 221 printf("Bad trap at PC: %lx, SR: %lx, vector=%lx\n", 222 regs->nip, regs->msr, regs->trap); 223 _exception(0, regs); 224 } 225 226 #if defined(CONFIG_CMD_BEDBUG) 227 extern void do_bedbug_breakpoint(struct pt_regs *); 228 #endif 229 230 void 231 DebugException(struct pt_regs *regs) 232 { 233 printf("Debugger trap at @ %lx\n", regs->nip ); 234 show_regs(regs); 235 #if defined(CONFIG_CMD_BEDBUG) 236 do_bedbug_breakpoint( regs ); 237 #endif 238 } 239 240 /* Probe an address by reading. If not present, return -1, otherwise 241 * return 0. 242 */ 243 int 244 addr_probe(uint *addr) 245 { 246 #if 0 247 int retval; 248 249 __asm__ __volatile__( \ 250 "1: lwz %0,0(%1)\n" \ 251 " eieio\n" \ 252 " li %0,0\n" \ 253 "2:\n" \ 254 ".section .fixup,\"ax\"\n" \ 255 "3: li %0,-1\n" \ 256 " b 2b\n" \ 257 ".section __ex_table,\"a\"\n" \ 258 " .align 2\n" \ 259 " .long 1b,3b\n" \ 260 ".text" \ 261 : "=r" (retval) : "r"(addr)); 262 263 return (retval); 264 #endif 265 return 0; 266 } 267