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
22 #include <asm/processor.h>
24 /* Returns 0 if exception not found and fixup otherwise. */
25 extern unsigned long search_exception_table(unsigned long);
27 /* THIS NEEDS CHANGING to use the board info structure.
29 #define END_OF_MEM 0x02000000
32 * Trap & Exception support
35 static void print_backtrace(unsigned long *sp
)
40 printf("Call backtrace: ");
42 if ((uint
)sp
> END_OF_MEM
)
50 sp
= (unsigned long *)*sp
;
55 void show_regs(struct pt_regs
*regs
)
59 printf("NIP: %08lX XER: %08lX LR: %08lX REGS:"
60 " %p TRAP: %04lx DAR: %08lX\n",
61 regs
->nip
, regs
->xer
, regs
->link
, regs
, regs
->trap
, regs
->dar
);
62 printf("MSR: %08lx EE: %01x PR: %01x FP:"
63 " %01x ME: %01x IR/DR: %01x%01x\n",
64 regs
->msr
, regs
->msr
&MSR_EE
? 1 : 0, regs
->msr
&MSR_PR
? 1 : 0,
65 regs
->msr
& MSR_FP
? 1 : 0,regs
->msr
&MSR_ME
? 1 : 0,
66 regs
->msr
&MSR_IR
? 1 : 0,
67 regs
->msr
&MSR_DR
? 1 : 0);
70 for (i
= 0; i
< 32; i
++) {
73 printf("GPR%02d: ", i
);
76 printf("%08lX ", regs
->gpr
[i
]);
85 static void _exception(int signr
, struct pt_regs
*regs
)
88 print_backtrace((unsigned long *)regs
->gpr
[1]);
89 panic("Exception in kernel pc %lx signal %d",regs
->nip
,signr
);
92 void MachineCheckException(struct pt_regs
*regs
)
96 /* Probing PCI using config cycles cause this exception
97 * when a device is not present. Catch it and return to
98 * the PCI exception handler.
100 if ((fixup
= search_exception_table(regs
->nip
)) != 0) {
105 #if defined(CONFIG_CMD_KGDB)
106 if (debugger_exception_handler
&& (*debugger_exception_handler
)(regs
))
110 printf("Machine check in kernel mode.\n");
111 printf("Caused by (from msr): ");
112 printf("regs %p ",regs
);
113 switch( regs
->msr
& 0x000F0000) {
114 case (0x80000000>>12):
115 printf("Machine check signal - probably due to mm fault\n"
118 case (0x80000000>>13):
119 printf("Transfer error ack signal\n");
121 case (0x80000000>>14):
122 printf("Data parity signal\n");
124 case (0x80000000>>15):
125 printf("Address parity signal\n");
128 printf("Unknown values in msr\n");
131 print_backtrace((unsigned long *)regs
->gpr
[1]);
132 panic("machine check");
135 void AlignmentException(struct pt_regs
*regs
)
137 #if defined(CONFIG_CMD_KGDB)
138 if (debugger_exception_handler
&& (*debugger_exception_handler
)(regs
))
142 print_backtrace((unsigned long *)regs
->gpr
[1]);
143 panic("Alignment Exception");
146 void ProgramCheckException(struct pt_regs
*regs
)
148 unsigned char *p
= regs
? (unsigned char *)(regs
->nip
) : NULL
;
151 #if defined(CONFIG_CMD_KGDB)
152 if (debugger_exception_handler
&& (*debugger_exception_handler
)(regs
))
157 p
= (unsigned char *) ((unsigned long)p
& 0xFFFFFFE0);
159 for (i
= 0; i
< 256; i
+=16) {
160 printf("%08x: ", (unsigned int)p
+i
);
161 for (j
= 0; j
< 16; j
++) {
162 printf("%02x ", p
[i
+j
]);
167 print_backtrace((unsigned long *)regs
->gpr
[1]);
168 panic("Program Check Exception");
171 void SoftEmuException(struct pt_regs
*regs
)
173 #if defined(CONFIG_CMD_KGDB)
174 if (debugger_exception_handler
&& (*debugger_exception_handler
)(regs
))
178 print_backtrace((unsigned long *)regs
->gpr
[1]);
179 panic("Software Emulation Exception");
182 void UnknownException(struct pt_regs
*regs
)
184 #if defined(CONFIG_CMD_KGDB)
185 if (debugger_exception_handler
&& (*debugger_exception_handler
)(regs
))
188 printf("Bad trap at PC: %lx, SR: %lx, vector=%lx\n",
189 regs
->nip
, regs
->msr
, regs
->trap
);
193 /* Probe an address by reading. If not present, return -1, otherwise
196 int addr_probe(uint
*addr
)
201 __asm__
__volatile__( \
202 "1: lwz %0,0(%1)\n" \
206 ".section .fixup,\"ax\"\n" \
209 ".section __ex_table,\"a\"\n" \
213 : "=r" (retval
) : "r"(addr
));