1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * (C) Copyright 2000
4 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
5 *
6 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
7 */
8
9 /*
10 * This file handles the architecture-dependent parts of hardware
11 * exceptions
12 */
13
14 #include <common.h>
15 #include <command.h>
16 #include <kgdb.h>
17 #include <asm/processor.h>
18 #include <asm/mpc8349_pci.h>
19
20 DECLARE_GLOBAL_DATA_PTR;
21
22 /* Returns 0 if exception not found and fixup otherwise. */
23 extern unsigned long search_exception_table(unsigned long);
24
25 #define END_OF_MEM (gd->bd->bi_memstart + gd->bd->bi_memsize)
26
27 /*
28 * Trap & Exception support
29 */
30
print_backtrace(unsigned long * sp)31 static void print_backtrace(unsigned long *sp)
32 {
33 int cnt = 0;
34 unsigned long i;
35
36 puts ("Call backtrace: ");
37 while (sp) {
38 if ((uint)sp > END_OF_MEM)
39 break;
40
41 i = sp[1];
42 if (cnt++ % 7 == 0)
43 putc ('\n');
44 printf("%08lX ", i);
45 if (cnt > 32) break;
46 sp = (unsigned long *)*sp;
47 }
48 putc ('\n');
49 }
50
show_regs(struct pt_regs * regs)51 void show_regs(struct pt_regs *regs)
52 {
53 int i;
54
55 printf("NIP: %08lX XER: %08lX LR: %08lX REGS: %p TRAP: %04lx DAR: %08lX\n",
56 regs->nip, regs->xer, regs->link, regs, regs->trap, regs->dar);
57 printf("MSR: %08lx EE: %01x PR: %01x FP: %01x ME: %01x IR/DR: %01x%01x\n",
58 regs->msr, regs->msr&MSR_EE ? 1 : 0, regs->msr&MSR_PR ? 1 : 0,
59 regs->msr & MSR_FP ? 1 : 0,regs->msr&MSR_ME ? 1 : 0,
60 regs->msr&MSR_IR ? 1 : 0,
61 regs->msr&MSR_DR ? 1 : 0);
62
63 putc ('\n');
64 for (i = 0; i < 32; i++) {
65 if ((i % 8) == 0) {
66 printf("GPR%02d: ", i);
67 }
68
69 printf("%08lX ", regs->gpr[i]);
70 if ((i % 8) == 7) {
71 putc ('\n');
72 }
73 }
74 }
75
76
_exception(int signr,struct pt_regs * regs)77 static void _exception(int signr, struct pt_regs *regs)
78 {
79 show_regs(regs);
80 print_backtrace((unsigned long *)regs->gpr[1]);
81 panic("Exception in kernel pc %lx signal %d",regs->nip,signr);
82 }
83
84 #ifdef CONFIG_PCI
dump_pci(void)85 void dump_pci (void)
86 {
87 /*
88 volatile immap_t *immap = (immap_t *) CONFIG_SYS_IMMR;
89 printf ("PCI: err status %x err mask %x err ctrl %x\n",
90 le32_to_cpu (immap->im_pci.pci_esr),
91 le32_to_cpu (immap->im_pci.pci_emr),
92 le32_to_cpu (immap->im_pci.pci_ecr));
93 printf (" error address %x error data %x ctrl %x\n",
94 le32_to_cpu (immap->im_pci.pci_eacr),
95 le32_to_cpu (immap->im_pci.pci_edcr),
96 le32_to_cpu (immap->im_pci.pci_eccr));
97 */
98 }
99 #endif
100
MachineCheckException(struct pt_regs * regs)101 void MachineCheckException(struct pt_regs *regs)
102 {
103 unsigned long fixup;
104
105 /* Probing PCI using config cycles cause this exception
106 * when a device is not present. Catch it and return to
107 * the PCI exception handler.
108 */
109 #ifdef CONFIG_PCI
110 #if 0
111 volatile immap_t *immap = (immap_t *)CONFIG_SYS_IMMR;
112 #ifdef DEBUG
113 dump_pci();
114 #endif
115 /* clear the error in the error status register */
116 if(immap->im_pci.pci_esr & cpu_to_le32(PCI_ERROR_PCI_NO_RSP)) {
117 immap->im_pci.pci_esr = cpu_to_le32(PCI_ERROR_PCI_NO_RSP);
118 return;
119 }
120 #endif
121 #endif /* CONFIG_PCI */
122 if ((fixup = search_exception_table(regs->nip)) != 0) {
123 regs->nip = fixup;
124 return;
125 }
126
127 #if defined(CONFIG_CMD_KGDB)
128 if (debugger_exception_handler && (*debugger_exception_handler)(regs))
129 return;
130 #endif
131
132 puts ("Machine check in kernel mode.\n"
133 "Caused by (from msr): ");
134 printf("regs %p ",regs);
135 switch( regs->msr & 0x000F0000) {
136 case (0x80000000>>12):
137 puts ("Machine check signal - probably due to mm fault\n"
138 "with mmu off\n");
139 break;
140 case (0x80000000>>13):
141 puts ("Transfer error ack signal\n");
142 break;
143 case (0x80000000>>14):
144 puts ("Data parity signal\n");
145 break;
146 case (0x80000000>>15):
147 puts ("Address parity signal\n");
148 break;
149 default:
150 puts ("Unknown values in msr\n");
151 }
152 show_regs(regs);
153 print_backtrace((unsigned long *)regs->gpr[1]);
154 #ifdef CONFIG_PCI
155 dump_pci();
156 #endif
157 panic("machine check");
158 }
159
AlignmentException(struct pt_regs * regs)160 void AlignmentException(struct pt_regs *regs)
161 {
162 #if defined(CONFIG_CMD_KGDB)
163 if (debugger_exception_handler && (*debugger_exception_handler)(regs))
164 return;
165 #endif
166 show_regs(regs);
167 print_backtrace((unsigned long *)regs->gpr[1]);
168 panic("Alignment Exception");
169 }
170
ProgramCheckException(struct pt_regs * regs)171 void ProgramCheckException(struct pt_regs *regs)
172 {
173 #if defined(CONFIG_CMD_KGDB)
174 if (debugger_exception_handler && (*debugger_exception_handler)(regs))
175 return;
176 #endif
177 show_regs(regs);
178 print_backtrace((unsigned long *)regs->gpr[1]);
179 panic("Program Check Exception");
180 }
181
SoftEmuException(struct pt_regs * regs)182 void SoftEmuException(struct pt_regs *regs)
183 {
184 #if defined(CONFIG_CMD_KGDB)
185 if (debugger_exception_handler && (*debugger_exception_handler)(regs))
186 return;
187 #endif
188 show_regs(regs);
189 print_backtrace((unsigned long *)regs->gpr[1]);
190 panic("Software Emulation Exception");
191 }
192
193
UnknownException(struct pt_regs * regs)194 void UnknownException(struct pt_regs *regs)
195 {
196 #if defined(CONFIG_CMD_KGDB)
197 if (debugger_exception_handler && (*debugger_exception_handler)(regs))
198 return;
199 #endif
200 printf("Bad trap at PC: %lx, SR: %lx, vector=%lx\n",
201 regs->nip, regs->msr, regs->trap);
202 _exception(0, regs);
203 }
204
205 #if defined(CONFIG_CMD_BEDBUG)
206 extern void do_bedbug_breakpoint(struct pt_regs *);
207 #endif
208
DebugException(struct pt_regs * regs)209 void DebugException(struct pt_regs *regs)
210 {
211 printf("Debugger trap at @ %lx\n", regs->nip );
212 show_regs(regs);
213 #if defined(CONFIG_CMD_BEDBUG)
214 do_bedbug_breakpoint( regs );
215 #endif
216 }
217