xref: /openbmc/u-boot/arch/powerpc/cpu/mpc86xx/traps.c (revision ed56fb1d)
1 /*
2  * Copyright (C) 1995-1996  Gary Thomas (gdt@linuxppc.org)
3  *
4  * Modified by Cort Dougan (cort@cs.nmt.edu)
5  * and Paul Mackerras (paulus@cs.anu.edu.au)
6  *
7  * (C) Copyright 2000
8  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
9  *
10  * See file CREDITS for list of people who contributed to this
11  * project.
12  *
13  * This program is free software; you can redistribute it and/or
14  * modify it under the terms of the GNU General Public License as
15  * published by the Free Software Foundation; either version 2 of
16  * the License, or (at your option) any later version.
17  *
18  * This program is distributed in the hope that it will be useful,
19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
21  * GNU General Public License for more details.
22  *
23  * You should have received a copy of the GNU General Public License
24  * along with this program; if not, write to the Free Software
25  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
26  * MA 02111-1307 USA
27  */
28 
29 /*
30  * This file handles the architecture-dependent parts of hardware exceptions
31  */
32 
33 #include <common.h>
34 #include <command.h>
35 #include <kgdb.h>
36 #include <asm/processor.h>
37 
38 DECLARE_GLOBAL_DATA_PTR;
39 
40 /* Returns 0 if exception not found and fixup otherwise.  */
41 extern unsigned long search_exception_table(unsigned long);
42 
43 /*
44  * End of addressable memory.  This may be less than the actual
45  * amount of memory on the system if we're unable to keep all
46  * the memory mapped in.
47  */
48 extern ulong get_effective_memsize(void);
49 #define END_OF_MEM (gd->bd->bi_memstart + get_effective_memsize())
50 
51 /*
52  * Trap & Exception support
53  */
54 
55 void
56 print_backtrace(unsigned long *sp)
57 {
58 	int cnt = 0;
59 	unsigned long i;
60 
61 	printf("Call backtrace: ");
62 	while (sp) {
63 		if ((uint) sp > END_OF_MEM)
64 			break;
65 
66 		i = sp[1];
67 		if (cnt++ % 7 == 0)
68 			printf("\n");
69 		printf("%08lX ", i);
70 		if (cnt > 32)
71 			break;
72 		sp = (unsigned long *)*sp;
73 	}
74 	printf("\n");
75 }
76 
77 void
78 show_regs(struct pt_regs *regs)
79 {
80 	int i;
81 
82 	printf("NIP: %08lX XER: %08lX LR: %08lX REGS:"
83 	       " %p TRAP: %04lx DAR: %08lX\n",
84 	       regs->nip, regs->xer, regs->link, regs, regs->trap, regs->dar);
85 	printf("MSR: %08lx EE: %01x PR: %01x FP:"
86 	       " %01x ME: %01x IR/DR: %01x%01x\n",
87 	       regs->msr, regs->msr & MSR_EE ? 1 : 0,
88 	       regs->msr & MSR_PR ? 1 : 0, regs->msr & MSR_FP ? 1 : 0,
89 	       regs->msr & MSR_ME ? 1 : 0, regs->msr & MSR_IR ? 1 : 0,
90 	       regs->msr & MSR_DR ? 1 : 0);
91 
92 	printf("\n");
93 	for (i = 0; i < 32; i++) {
94 		if ((i % 8) == 0) {
95 			printf("GPR%02d: ", i);
96 		}
97 
98 		printf("%08lX ", regs->gpr[i]);
99 		if ((i % 8) == 7) {
100 			printf("\n");
101 		}
102 	}
103 }
104 
105 
106 void
107 _exception(int signr, struct pt_regs *regs)
108 {
109 	show_regs(regs);
110 	print_backtrace((unsigned long *)regs->gpr[1]);
111 	panic("Exception in kernel pc %lx signal %d", regs->nip, signr);
112 }
113 
114 void
115 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 	if ((fixup = search_exception_table(regs->nip)) != 0) {
124 		regs->nip = fixup;
125 		return;
126 	}
127 
128 #if defined(CONFIG_CMD_KGDB)
129 	if (debugger_exception_handler && (*debugger_exception_handler) (regs))
130 		return;
131 #endif
132 
133 	printf("Machine check in kernel mode.\n");
134 	printf("Caused by (from msr): ");
135 	printf("regs %p ", regs);
136 	switch ( regs->msr & 0x001F0000) {
137 	case (0x80000000>>11):
138 		printf("MSS error. MSSSR0: %08x\n", mfspr(SPRN_MSSSR0));
139 		break;
140 	case (0x80000000>>12):
141 		printf("Machine check signal - probably due to mm fault\n"
142 		       "with mmu off\n");
143 		break;
144 	case (0x80000000 >> 13):
145 		printf("Transfer error ack signal\n");
146 		break;
147 	case (0x80000000 >> 14):
148 		printf("Data parity signal\n");
149 		break;
150 	case (0x80000000 >> 15):
151 		printf("Address parity signal\n");
152 		break;
153 	default:
154 		printf("Unknown values in msr\n");
155 	}
156 	show_regs(regs);
157 	print_backtrace((unsigned long *)regs->gpr[1]);
158 	panic("machine check");
159 }
160 
161 void
162 AlignmentException(struct pt_regs *regs)
163 {
164 #if defined(CONFIG_CMD_KGDB)
165 	if (debugger_exception_handler && (*debugger_exception_handler) (regs))
166 		return;
167 #endif
168 	show_regs(regs);
169 	print_backtrace((unsigned long *)regs->gpr[1]);
170 	panic("Alignment Exception");
171 }
172 
173 void
174 ProgramCheckException(struct pt_regs *regs)
175 {
176 	unsigned char *p = regs ? (unsigned char *)(regs->nip) : NULL;
177 	int i, j;
178 
179 #if defined(CONFIG_CMD_KGDB)
180 	if (debugger_exception_handler && (*debugger_exception_handler) (regs))
181 		return;
182 #endif
183 	show_regs(regs);
184 
185 	p = (unsigned char *)((unsigned long)p & 0xFFFFFFE0);
186 	p -= 32;
187 	for (i = 0; i < 256; i += 16) {
188 		printf("%08x: ", (unsigned int)p + i);
189 		for (j = 0; j < 16; j++) {
190 			printf("%02x ", p[i + j]);
191 		}
192 		printf("\n");
193 	}
194 
195 	print_backtrace((unsigned long *)regs->gpr[1]);
196 	panic("Program Check Exception");
197 }
198 
199 void
200 SoftEmuException(struct pt_regs *regs)
201 {
202 #if defined(CONFIG_CMD_KGDB)
203 	if (debugger_exception_handler && (*debugger_exception_handler) (regs))
204 		return;
205 #endif
206 	show_regs(regs);
207 	print_backtrace((unsigned long *)regs->gpr[1]);
208 	panic("Software Emulation Exception");
209 }
210 
211 void
212 UnknownException(struct pt_regs *regs)
213 {
214 #if defined(CONFIG_CMD_KGDB)
215 	if (debugger_exception_handler && (*debugger_exception_handler) (regs))
216 		return;
217 #endif
218 	printf("UnknownException regs@%lx\n", (ulong)regs);
219 	printf("Bad trap at PC: %lx, SR: %lx, vector=%lx\n",
220 	       regs->nip, regs->msr, regs->trap);
221 	_exception(0, regs);
222 }
223 
224 /*
225  * Probe an address by reading.
226  * If not present, return -1,
227  * otherwise return 0.
228  */
229 int
230 addr_probe(uint *addr)
231 {
232 	return 0;
233 }
234