2 * linux/arch/ppc/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 * See file CREDITS for list of people who contributed to this
15 * This program is free software; you can redistribute it and/or
16 * modify it under the terms of the GNU General Public License as
17 * published by the Free Software Foundation; either version 2 of
18 * the License, or (at your option) any later version.
20 * This program is distributed in the hope that it will be useful,
21 * but WITHOUT ANY WARRANTY; without even the implied warranty of
22 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
23 * GNU General Public License for more details.
25 * You should have received a copy of the GNU General Public License
26 * along with this program; if not, write to the Free Software
27 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
32 * This file handles the architecture-dependent parts of hardware exceptions
37 #include <asm/processor.h>
39 #if (CONFIG_COMMANDS & CFG_CMD_KGDB)
40 int (*debugger_exception_handler
)(struct pt_regs
*) = 0;
43 /* Returns 0 if exception not found and fixup otherwise. */
44 extern unsigned long search_exception_table(unsigned long);
46 /* THIS NEEDS CHANGING to use the board info structure.
48 #define END_OF_MEM 0x02000000
51 * Trap & Exception support
55 print_backtrace(unsigned long *sp
)
60 printf("Call backtrace: ");
62 if ((uint
)sp
> END_OF_MEM
)
70 sp
= (unsigned long *)*sp
;
75 void show_regs(struct pt_regs
* regs
)
79 printf("NIP: %08lX XER: %08lX LR: %08lX REGS: %p TRAP: %04lx DAR: %08lX\n",
80 regs
->nip
, regs
->xer
, regs
->link
, regs
, regs
->trap
, regs
->dar
);
81 printf("MSR: %08lx EE: %01x PR: %01x FP: %01x ME: %01x IR/DR: %01x%01x\n",
82 regs
->msr
, regs
->msr
&MSR_EE
? 1 : 0, regs
->msr
&MSR_PR
? 1 : 0,
83 regs
->msr
& MSR_FP
? 1 : 0,regs
->msr
&MSR_ME
? 1 : 0,
84 regs
->msr
&MSR_IR
? 1 : 0,
85 regs
->msr
&MSR_DR
? 1 : 0);
88 for (i
= 0; i
< 32; i
++) {
91 printf("GPR%02d: ", i
);
94 printf("%08lX ", regs
->gpr
[i
]);
104 _exception(int signr
, struct pt_regs
*regs
)
107 print_backtrace((unsigned long *)regs
->gpr
[1]);
108 panic("Exception in kernel pc %lx signal %d",regs
->nip
,signr
);
112 MachineCheckException(struct pt_regs
*regs
)
116 /* Probing PCI using config cycles cause this exception
117 * when a device is not present. Catch it and return to
118 * the PCI exception handler.
120 if ((fixup
= search_exception_table(regs
->nip
)) != 0) {
125 #if (CONFIG_COMMANDS & CFG_CMD_KGDB)
126 if (debugger_exception_handler
&& (*debugger_exception_handler
)(regs
))
130 printf("Machine check in kernel mode.\n");
131 printf("Caused by (from msr): ");
132 printf("regs %p ",regs
);
133 switch( regs
->msr
& 0x0000F000)
136 printf("Machine check signal - probably due to mm fault\n"
140 printf("Transfer error ack signal\n");
143 printf("Data parity signal\n");
146 printf("Address parity signal\n");
149 printf("Unknown values in msr\n");
152 print_backtrace((unsigned long *)regs
->gpr
[1]);
153 panic("machine check");
157 AlignmentException(struct pt_regs
*regs
)
159 #if (CONFIG_COMMANDS & CFG_CMD_KGDB)
160 if (debugger_exception_handler
&& (*debugger_exception_handler
)(regs
))
164 print_backtrace((unsigned long *)regs
->gpr
[1]);
165 panic("Alignment Exception");
169 ProgramCheckException(struct pt_regs
*regs
)
171 #if (CONFIG_COMMANDS & CFG_CMD_KGDB)
172 if (debugger_exception_handler
&& (*debugger_exception_handler
)(regs
))
176 print_backtrace((unsigned long *)regs
->gpr
[1]);
177 panic("Program Check Exception");
181 SoftEmuException(struct pt_regs
*regs
)
183 #if (CONFIG_COMMANDS & CFG_CMD_KGDB)
184 if (debugger_exception_handler
&& (*debugger_exception_handler
)(regs
))
188 print_backtrace((unsigned long *)regs
->gpr
[1]);
189 panic("Software Emulation Exception");
194 UnknownException(struct pt_regs
*regs
)
196 #if (CONFIG_COMMANDS & CFG_CMD_KGDB)
197 if (debugger_exception_handler
&& (*debugger_exception_handler
)(regs
))
200 printf("Bad trap at PC: %lx, SR: %lx, vector=%lx\n",
201 regs
->nip
, regs
->msr
, regs
->trap
);
205 #if (CONFIG_COMMANDS & CFG_CMD_BEDBUG)
206 extern void do_bedbug_breakpoint(struct pt_regs
*);
210 DebugException(struct pt_regs
*regs
)
213 printf("Debugger trap at @ %lx\n", regs
->nip
);
215 #if (CONFIG_COMMANDS & CFG_CMD_BEDBUG)
216 do_bedbug_breakpoint( regs
);
220 /* Probe an address by reading. If not present, return -1, otherwise
224 addr_probe(uint
*addr
)
229 __asm__
__volatile__( \
230 "1: lwz %0,0(%1)\n" \
234 ".section .fixup,\"ax\"\n" \
237 ".section __ex_table,\"a\"\n" \
241 : "=r" (retval
) : "r"(addr
));