1/*
2 * Copyright (C) 2003, Axis Communications AB.
3 */
4
5#include <linux/ptrace.h>
6#include <asm/uaccess.h>
7
8#include <asm/arch/hwregs/supp_reg.h>
9
10extern void reset_watchdog(void);
11extern void stop_watchdog(void);
12
13extern int raw_printk(const char *fmt, ...);
14
15void
16show_registers(struct pt_regs *regs)
17{
18	/*
19	 * It's possible to use either the USP register or current->thread.usp.
20	 * USP might not correspond to the current proccess for all cases this
21	 * function is called, and current->thread.usp isn't up to date for the
22	 * current proccess. Experience shows that using USP is the way to go.
23	 */
24	unsigned long usp;
25	unsigned long d_mmu_cause;
26	unsigned long i_mmu_cause;
27
28	usp = rdusp();
29
30	raw_printk("CPU: %d\n", smp_processor_id());
31
32	raw_printk("ERP: %08lx SRP: %08lx  CCS: %08lx USP: %08lx MOF: %08lx\n",
33		regs->erp, regs->srp, regs->ccs, usp, regs->mof);
34
35	raw_printk(" r0: %08lx  r1: %08lx   r2: %08lx  r3: %08lx\n",
36		regs->r0, regs->r1, regs->r2, regs->r3);
37
38	raw_printk(" r4: %08lx  r5: %08lx   r6: %08lx  r7: %08lx\n",
39		regs->r4, regs->r5, regs->r6, regs->r7);
40
41	raw_printk(" r8: %08lx  r9: %08lx  r10: %08lx r11: %08lx\n",
42		regs->r8, regs->r9, regs->r10, regs->r11);
43
44	raw_printk("r12: %08lx r13: %08lx oR10: %08lx acr: %08lx\n",
45		regs->r12, regs->r13, regs->orig_r10, regs->acr);
46
47	raw_printk("sp: %08lx\n", regs);
48
49	SUPP_BANK_SEL(BANK_IM);
50	SUPP_REG_RD(RW_MM_CAUSE, i_mmu_cause);
51
52	SUPP_BANK_SEL(BANK_DM);
53	SUPP_REG_RD(RW_MM_CAUSE, d_mmu_cause);
54
55	raw_printk("       Data MMU Cause: %08lx\n", d_mmu_cause);
56	raw_printk("Instruction MMU Cause: %08lx\n", i_mmu_cause);
57
58	raw_printk("Process %s (pid: %d, stackpage: %08lx)\n",
59		current->comm, current->pid, (unsigned long) current);
60
61	/* Show additional info if in kernel-mode. */
62	if (!user_mode(regs)) {
63		int i;
64		unsigned char c;
65
66		show_stack(NULL, (unsigned long *) usp);
67
68		/*
69		 * If the previous stack-dump wasn't a kernel one, dump the
70		 * kernel stack now.
71		 */
72		if (usp != 0)
73			show_stack(NULL, NULL);
74
75		raw_printk("\nCode: ");
76
77		if (regs->erp < PAGE_OFFSET)
78			goto bad_value;
79
80		/*
81		 * Quite often the value at regs->erp doesn't point to the
82		 * interesting instruction, which often is the previous
83		 * instruction. So dump at an offset large enough that the
84		 * instruction decoding should be in sync at the interesting
85		 * point, but small enough to fit on a row. The regs->erp
86		 * location is pointed out in a ksymoops-friendly way by
87		 * wrapping the byte for that address in parenthesis.
88		 */
89		for (i = -12; i < 12; i++) {
90			if (__get_user(c, &((unsigned char *) regs->erp)[i])) {
91bad_value:
92				raw_printk(" Bad IP value.");
93				break;
94			}
95
96			if (i == 0)
97				raw_printk("(%02x) ", c);
98			else
99				raw_printk("%02x ", c);
100		}
101
102		raw_printk("\n");
103	}
104}
105
106/*
107 * This gets called from entry.S when the watchdog has bitten. Show something
108 * similiar to an Oops dump, and if the kernel if configured to be a nice doggy;
109 * halt instead of reboot.
110 */
111void
112watchdog_bite_hook(struct pt_regs *regs)
113{
114#ifdef CONFIG_ETRAX_WATCHDOG_NICE_DOGGY
115	local_irq_disable();
116	stop_watchdog();
117	show_registers(regs);
118
119	while (1)
120		; /* Do nothing. */
121#else
122	show_registers(regs);
123#endif
124}
125
126/* This is normally the Oops function. */
127void
128die_if_kernel(const char *str, struct pt_regs *regs, long err)
129{
130	if (user_mode(regs))
131		return;
132
133#ifdef CONFIG_ETRAX_WATCHDOG_NICE_DOGGY
134	/*
135	 * This printout might take too long and could trigger
136	 * the watchdog normally. If NICE_DOGGY is set, simply
137	 * stop the watchdog during the printout.
138	 */
139	stop_watchdog();
140#endif
141
142	raw_printk("%s: %04lx\n", str, err & 0xffff);
143
144	show_registers(regs);
145
146#ifdef CONFIG_ETRAX_WATCHDOG_NICE_DOGGY
147	reset_watchdog();
148#endif
149
150	do_exit(SIGSEGV);
151}
152
153void arch_enable_nmi(void)
154{
155	unsigned long flags;
156	local_save_flags(flags);
157	flags |= (1<<30); /* NMI M flag is at bit 30 */
158	local_irq_restore(flags);
159}
160