xref: /openbmc/u-boot/arch/powerpc/cpu/mpc83xx/traps.c (revision dd1033e4)
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 
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 
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 
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
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 
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 
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 
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 
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 
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 
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