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 static void print_backtrace(unsigned long *sp) 46 { 47 int cnt = 0; 48 unsigned long i; 49 50 puts ("Call backtrace: "); 51 while (sp) { 52 if ((uint)sp > END_OF_MEM) 53 break; 54 55 i = sp[1]; 56 if (cnt++ % 7 == 0) 57 putc ('\n'); 58 printf("%08lX ", i); 59 if (cnt > 32) break; 60 sp = (unsigned long *)*sp; 61 } 62 putc ('\n'); 63 } 64 65 void show_regs(struct pt_regs *regs) 66 { 67 int i; 68 69 printf("NIP: %08lX XER: %08lX LR: %08lX REGS: %p TRAP: %04lx DAR: %08lX\n", 70 regs->nip, regs->xer, regs->link, regs, regs->trap, regs->dar); 71 printf("MSR: %08lx EE: %01x PR: %01x FP: %01x ME: %01x IR/DR: %01x%01x\n", 72 regs->msr, regs->msr&MSR_EE ? 1 : 0, regs->msr&MSR_PR ? 1 : 0, 73 regs->msr & MSR_FP ? 1 : 0,regs->msr&MSR_ME ? 1 : 0, 74 regs->msr&MSR_IR ? 1 : 0, 75 regs->msr&MSR_DR ? 1 : 0); 76 77 putc ('\n'); 78 for (i = 0; i < 32; i++) { 79 if ((i % 8) == 0) { 80 printf("GPR%02d: ", i); 81 } 82 83 printf("%08lX ", regs->gpr[i]); 84 if ((i % 8) == 7) { 85 putc ('\n'); 86 } 87 } 88 } 89 90 91 static void _exception(int signr, struct pt_regs *regs) 92 { 93 show_regs(regs); 94 print_backtrace((unsigned long *)regs->gpr[1]); 95 panic("Exception in kernel pc %lx signal %d",regs->nip,signr); 96 } 97 98 #ifdef CONFIG_PCI 99 void dump_pci (void) 100 { 101 /* 102 volatile immap_t *immap = (immap_t *) CONFIG_SYS_IMMR; 103 printf ("PCI: err status %x err mask %x err ctrl %x\n", 104 le32_to_cpu (immap->im_pci.pci_esr), 105 le32_to_cpu (immap->im_pci.pci_emr), 106 le32_to_cpu (immap->im_pci.pci_ecr)); 107 printf (" error address %x error data %x ctrl %x\n", 108 le32_to_cpu (immap->im_pci.pci_eacr), 109 le32_to_cpu (immap->im_pci.pci_edcr), 110 le32_to_cpu (immap->im_pci.pci_eccr)); 111 */ 112 } 113 #endif 114 115 void MachineCheckException(struct pt_regs *regs) 116 { 117 unsigned long fixup; 118 119 /* Probing PCI using config cycles cause this exception 120 * when a device is not present. Catch it and return to 121 * the PCI exception handler. 122 */ 123 #ifdef CONFIG_PCI 124 #if 0 125 volatile immap_t *immap = (immap_t *)CONFIG_SYS_IMMR; 126 #ifdef DEBUG 127 dump_pci(); 128 #endif 129 /* clear the error in the error status register */ 130 if(immap->im_pci.pci_esr & cpu_to_le32(PCI_ERROR_PCI_NO_RSP)) { 131 immap->im_pci.pci_esr = cpu_to_le32(PCI_ERROR_PCI_NO_RSP); 132 return; 133 } 134 #endif 135 #endif /* CONFIG_PCI */ 136 if ((fixup = search_exception_table(regs->nip)) != 0) { 137 regs->nip = fixup; 138 return; 139 } 140 141 #if defined(CONFIG_CMD_KGDB) 142 if (debugger_exception_handler && (*debugger_exception_handler)(regs)) 143 return; 144 #endif 145 146 puts ("Machine check in kernel mode.\n" 147 "Caused by (from msr): "); 148 printf("regs %p ",regs); 149 switch( regs->msr & 0x000F0000) { 150 case (0x80000000>>12): 151 puts ("Machine check signal - probably due to mm fault\n" 152 "with mmu off\n"); 153 break; 154 case (0x80000000>>13): 155 puts ("Transfer error ack signal\n"); 156 break; 157 case (0x80000000>>14): 158 puts ("Data parity signal\n"); 159 break; 160 case (0x80000000>>15): 161 puts ("Address parity signal\n"); 162 break; 163 default: 164 puts ("Unknown values in msr\n"); 165 } 166 show_regs(regs); 167 print_backtrace((unsigned long *)regs->gpr[1]); 168 #ifdef CONFIG_PCI 169 dump_pci(); 170 #endif 171 panic("machine check"); 172 } 173 174 void AlignmentException(struct pt_regs *regs) 175 { 176 #if defined(CONFIG_CMD_KGDB) 177 if (debugger_exception_handler && (*debugger_exception_handler)(regs)) 178 return; 179 #endif 180 show_regs(regs); 181 print_backtrace((unsigned long *)regs->gpr[1]); 182 panic("Alignment Exception"); 183 } 184 185 void ProgramCheckException(struct pt_regs *regs) 186 { 187 #if defined(CONFIG_CMD_KGDB) 188 if (debugger_exception_handler && (*debugger_exception_handler)(regs)) 189 return; 190 #endif 191 show_regs(regs); 192 print_backtrace((unsigned long *)regs->gpr[1]); 193 panic("Program Check Exception"); 194 } 195 196 void SoftEmuException(struct pt_regs *regs) 197 { 198 #if defined(CONFIG_CMD_KGDB) 199 if (debugger_exception_handler && (*debugger_exception_handler)(regs)) 200 return; 201 #endif 202 show_regs(regs); 203 print_backtrace((unsigned long *)regs->gpr[1]); 204 panic("Software Emulation Exception"); 205 } 206 207 208 void UnknownException(struct pt_regs *regs) 209 { 210 #if defined(CONFIG_CMD_KGDB) 211 if (debugger_exception_handler && (*debugger_exception_handler)(regs)) 212 return; 213 #endif 214 printf("Bad trap at PC: %lx, SR: %lx, vector=%lx\n", 215 regs->nip, regs->msr, regs->trap); 216 _exception(0, regs); 217 } 218 219 #if defined(CONFIG_CMD_BEDBUG) 220 extern void do_bedbug_breakpoint(struct pt_regs *); 221 #endif 222 223 void DebugException(struct pt_regs *regs) 224 { 225 printf("Debugger trap at @ %lx\n", regs->nip ); 226 show_regs(regs); 227 #if defined(CONFIG_CMD_BEDBUG) 228 do_bedbug_breakpoint( regs ); 229 #endif 230 } 231 232 /* Probe an address by reading. If not present, return -1, otherwise 233 * return 0. 234 */ 235 int addr_probe(uint *addr) 236 { 237 #if 0 238 int retval; 239 240 __asm__ __volatile__( \ 241 "1: lwz %0,0(%1)\n" \ 242 " eieio\n" \ 243 " li %0,0\n" \ 244 "2:\n" \ 245 ".section .fixup,\"ax\"\n" \ 246 "3: li %0,-1\n" \ 247 " b 2b\n" \ 248 ".section __ex_table,\"a\"\n" \ 249 " .align 2\n" \ 250 " .long 1b,3b\n" \ 251 ".text" \ 252 : "=r" (retval) : "r"(addr)); 253 254 return (retval); 255 #endif 256 return 0; 257 } 258