2 * linux/arch/powerpc/kernel/traps.c
4 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
6 * Modified by Cort Dougan (cort@cs.nmt.edu)
7 * and Paul Mackerras (paulus@cs.anu.edu.au)
10 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
12 * SPDX-License-Identifier: GPL-2.0+
16 * This file handles the architecture-dependent parts of hardware exceptions
20 #include <asm/processor.h>
22 /* Returns 0 if exception not found and fixup otherwise. */
23 extern unsigned long search_exception_table(unsigned long);
25 /* THIS NEEDS CHANGING to use the board info structure.
27 #define END_OF_MEM 0x00400000
30 * Trap & Exception support
33 static void print_backtrace(unsigned long *sp)
38 printf("Call backtrace: ");
40 if ((uint)sp > END_OF_MEM)
48 sp = (unsigned long *)*sp;
53 void show_regs(struct pt_regs *regs)
57 printf("NIP: %08lX XER: %08lX LR: %08lX REGS: %p TRAP: %04lx DAR: %08lX\n",
58 regs->nip, regs->xer, regs->link, regs, regs->trap, regs->dar);
59 printf("MSR: %08lx EE: %01x PR: %01x FP: %01x ME: %01x IR/DR: %01x%01x\n",
60 regs->msr, regs->msr&MSR_EE ? 1 : 0, regs->msr&MSR_PR ? 1 : 0,
61 regs->msr & MSR_FP ? 1 : 0,regs->msr&MSR_ME ? 1 : 0,
62 regs->msr&MSR_IR ? 1 : 0,
63 regs->msr&MSR_DR ? 1 : 0);
66 for (i = 0; i < 32; i++) {
69 printf("GPR%02d: ", i);
72 printf("%08lX ", regs->gpr[i]);
81 static void _exception(int signr, struct pt_regs *regs)
84 print_backtrace((unsigned long *)regs->gpr[1]);
85 panic("Exception in kernel pc %lx signal %d",regs->nip,signr);
88 void MachineCheckException(struct pt_regs *regs)
92 /* Probing PCI using config cycles cause this exception
93 * when a device is not present. Catch it and return to
94 * the PCI exception handler.
96 if ((fixup = search_exception_table(regs->nip)) != 0) {
101 printf("Machine check in kernel mode.\n");
102 printf("Caused by (from msr): ");
103 printf("regs %p ",regs);
104 switch( regs->msr & 0x000F0000) {
105 case (0x80000000>>12):
106 printf("Machine check signal - probably due to mm fault\n"
109 case (0x80000000>>13):
110 printf("Transfer error ack signal\n");
112 case (0x80000000>>14):
113 printf("Data parity signal\n");
115 case (0x80000000>>15):
116 printf("Address parity signal\n");
119 printf("Unknown values in msr\n");
122 print_backtrace((unsigned long *)regs->gpr[1]);
123 panic("machine check");
126 void AlignmentException(struct pt_regs *regs)
129 print_backtrace((unsigned long *)regs->gpr[1]);
130 panic("Alignment Exception");
133 void ProgramCheckException(struct pt_regs *regs)
136 print_backtrace((unsigned long *)regs->gpr[1]);
137 panic("Program Check Exception");
140 void SoftEmuException(struct pt_regs *regs)
143 print_backtrace((unsigned long *)regs->gpr[1]);
144 panic("Software Emulation Exception");
148 void UnknownException(struct pt_regs *regs)
150 printf("Bad trap at PC: %lx, SR: %lx, vector=%lx\n",
151 regs->nip, regs->msr, regs->trap);
155 #if defined(CONFIG_CMD_BEDBUG)
156 extern void do_bedbug_breakpoint(struct pt_regs *);
159 void DebugException(struct pt_regs *regs)
162 printf("Debugger trap at @ %lx\n", regs->nip );
164 #if defined(CONFIG_CMD_BEDBUG)
165 do_bedbug_breakpoint( regs );
169 /* Probe an address by reading. If not present, return -1, otherwise
172 int addr_probe(uint *addr)
177 __asm__ __volatile__( \
178 "1: lwz %0,0(%1)\n" \
182 ".section .fixup,\"ax\"\n" \
185 ".section __ex_table,\"a\"\n" \
189 : "=r" (retval) : "r"(addr));