1/*
2 * arch/score/kernel/traps.c
3 *
4 * Score Processor version.
5 *
6 * Copyright (C) 2009 Sunplus Core Technology Co., Ltd.
7 *  Chen Liqin <liqin.chen@sunplusct.com>
8 *  Lennox Wu <lennox.wu@sunplusct.com>
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18 * GNU General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, see the file COPYING, or write
22 * to the Free Software Foundation, Inc.,
23 * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
24 */
25
26#include <linux/module.h>
27#include <linux/sched.h>
28
29#include <asm/cacheflush.h>
30#include <asm/irq.h>
31#include <asm/irq_regs.h>
32
33unsigned long exception_handlers[32];
34
35/*
36 * The architecture-independent show_stack generator
37 */
38void show_stack(struct task_struct *task, unsigned long *sp)
39{
40	int i;
41	long stackdata;
42
43	sp = sp ? sp : (unsigned long *)&sp;
44
45	printk(KERN_NOTICE "Stack: ");
46	i = 1;
47	while ((long) sp & (PAGE_SIZE - 1)) {
48		if (i && ((i % 8) == 0))
49			printk(KERN_NOTICE "\n");
50		if (i > 40) {
51			printk(KERN_NOTICE " ...");
52			break;
53		}
54
55		if (__get_user(stackdata, sp++)) {
56			printk(KERN_NOTICE " (Bad stack address)");
57			break;
58		}
59
60		printk(KERN_NOTICE " %08lx", stackdata);
61		i++;
62	}
63	printk(KERN_NOTICE "\n");
64}
65
66static void show_trace(long *sp)
67{
68	int i;
69	long addr;
70
71	sp = sp ? sp : (long *) &sp;
72
73	printk(KERN_NOTICE "Call Trace:  ");
74	i = 1;
75	while ((long) sp & (PAGE_SIZE - 1)) {
76		if (__get_user(addr, sp++)) {
77			if (i && ((i % 6) == 0))
78				printk(KERN_NOTICE "\n");
79			printk(KERN_NOTICE " (Bad stack address)\n");
80			break;
81		}
82
83		if (kernel_text_address(addr)) {
84			if (i && ((i % 6) == 0))
85				printk(KERN_NOTICE "\n");
86			if (i > 40) {
87				printk(KERN_NOTICE " ...");
88				break;
89			}
90
91			printk(KERN_NOTICE " [<%08lx>]", addr);
92			i++;
93		}
94	}
95	printk(KERN_NOTICE "\n");
96}
97
98static void show_code(unsigned int *pc)
99{
100	long i;
101
102	printk(KERN_NOTICE "\nCode:");
103
104	for (i = -3; i < 6; i++) {
105		unsigned long insn;
106		if (__get_user(insn, pc + i)) {
107			printk(KERN_NOTICE " (Bad address in epc)\n");
108			break;
109		}
110		printk(KERN_NOTICE "%c%08lx%c", (i ? ' ' : '<'),
111			insn, (i ? ' ' : '>'));
112	}
113}
114
115/*
116 * FIXME: really the generic show_regs should take a const pointer argument.
117 */
118void show_regs(struct pt_regs *regs)
119{
120	show_regs_print_info(KERN_DEFAULT);
121
122	printk("r0 : %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
123		regs->regs[0], regs->regs[1], regs->regs[2], regs->regs[3],
124		regs->regs[4], regs->regs[5], regs->regs[6], regs->regs[7]);
125	printk("r8 : %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
126		regs->regs[8], regs->regs[9], regs->regs[10], regs->regs[11],
127		regs->regs[12], regs->regs[13], regs->regs[14], regs->regs[15]);
128	printk("r16: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
129		regs->regs[16], regs->regs[17], regs->regs[18], regs->regs[19],
130		regs->regs[20], regs->regs[21], regs->regs[22], regs->regs[23]);
131	printk("r24: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
132		regs->regs[24], regs->regs[25], regs->regs[26], regs->regs[27],
133		regs->regs[28], regs->regs[29], regs->regs[30], regs->regs[31]);
134
135	printk("CEH : %08lx\n", regs->ceh);
136	printk("CEL : %08lx\n", regs->cel);
137
138	printk("EMA:%08lx, epc:%08lx %s\nPSR: %08lx\nECR:%08lx\nCondition : %08lx\n",
139		regs->cp0_ema, regs->cp0_epc, print_tainted(), regs->cp0_psr,
140		regs->cp0_ecr, regs->cp0_condition);
141}
142
143static void show_registers(struct pt_regs *regs)
144{
145	show_regs(regs);
146	printk(KERN_NOTICE "Process %s (pid: %d, stackpage=%08lx)\n",
147		current->comm, current->pid, (unsigned long) current);
148	show_stack(current_thread_info()->task, (long *) regs->regs[0]);
149	show_trace((long *) regs->regs[0]);
150	show_code((unsigned int *) regs->cp0_epc);
151	printk(KERN_NOTICE "\n");
152}
153
154void __die(const char *str, struct pt_regs *regs, const char *file,
155	const char *func, unsigned long line)
156{
157	console_verbose();
158	printk("%s", str);
159	if (file && func)
160		printk(" in %s:%s, line %ld", file, func, line);
161	printk(":\n");
162	show_registers(regs);
163	do_exit(SIGSEGV);
164}
165
166void __die_if_kernel(const char *str, struct pt_regs *regs,
167		const char *file, const char *func, unsigned long line)
168{
169	if (!user_mode(regs))
170		__die(str, regs, file, func, line);
171}
172
173asmlinkage void do_adelinsn(struct pt_regs *regs)
174{
175	printk("do_ADE-linsn:ema:0x%08lx:epc:0x%08lx\n",
176		 regs->cp0_ema, regs->cp0_epc);
177	die_if_kernel("do_ade execution Exception\n", regs);
178	force_sig(SIGBUS, current);
179}
180
181asmlinkage void do_adedata(struct pt_regs *regs)
182{
183	const struct exception_table_entry *fixup;
184	fixup = search_exception_tables(regs->cp0_epc);
185	if (fixup) {
186		regs->cp0_epc = fixup->fixup;
187		return;
188	}
189	printk("do_ADE-data:ema:0x%08lx:epc:0x%08lx\n",
190		 regs->cp0_ema, regs->cp0_epc);
191	die_if_kernel("do_ade execution Exception\n", regs);
192	force_sig(SIGBUS, current);
193}
194
195asmlinkage void do_pel(struct pt_regs *regs)
196{
197	die_if_kernel("do_pel execution Exception", regs);
198	force_sig(SIGFPE, current);
199}
200
201asmlinkage void do_cee(struct pt_regs *regs)
202{
203	die_if_kernel("do_cee execution Exception", regs);
204	force_sig(SIGFPE, current);
205}
206
207asmlinkage void do_cpe(struct pt_regs *regs)
208{
209	die_if_kernel("do_cpe execution Exception", regs);
210	force_sig(SIGFPE, current);
211}
212
213asmlinkage void do_be(struct pt_regs *regs)
214{
215	die_if_kernel("do_be execution Exception", regs);
216	force_sig(SIGBUS, current);
217}
218
219asmlinkage void do_ov(struct pt_regs *regs)
220{
221	siginfo_t info;
222
223	die_if_kernel("do_ov execution Exception", regs);
224
225	info.si_code = FPE_INTOVF;
226	info.si_signo = SIGFPE;
227	info.si_errno = 0;
228	info.si_addr = (void *)regs->cp0_epc;
229	force_sig_info(SIGFPE, &info, current);
230}
231
232asmlinkage void do_tr(struct pt_regs *regs)
233{
234	die_if_kernel("do_tr execution Exception", regs);
235	force_sig(SIGTRAP, current);
236}
237
238asmlinkage void do_ri(struct pt_regs *regs)
239{
240	unsigned long epc_insn;
241	unsigned long epc = regs->cp0_epc;
242
243	read_tsk_long(current, epc, &epc_insn);
244	if (current->thread.single_step == 1) {
245		if ((epc == current->thread.addr1) ||
246		    (epc == current->thread.addr2)) {
247			user_disable_single_step(current);
248			force_sig(SIGTRAP, current);
249			return;
250		} else
251			BUG();
252	} else if ((epc_insn == BREAKPOINT32_INSN) ||
253		   ((epc_insn & 0x0000FFFF) == 0x7002) ||
254		   ((epc_insn & 0xFFFF0000) == 0x70020000)) {
255			force_sig(SIGTRAP, current);
256			return;
257	} else {
258		die_if_kernel("do_ri execution Exception", regs);
259		force_sig(SIGILL, current);
260	}
261}
262
263asmlinkage void do_ccu(struct pt_regs *regs)
264{
265	die_if_kernel("do_ccu execution Exception", regs);
266	force_sig(SIGILL, current);
267}
268
269asmlinkage void do_reserved(struct pt_regs *regs)
270{
271	/*
272	 * Game over - no way to handle this if it ever occurs.  Most probably
273	 * caused by a new unknown cpu type or after another deadly
274	 * hard/software error.
275	 */
276	die_if_kernel("do_reserved execution Exception", regs);
277	show_regs(regs);
278	panic("Caught reserved exception - should not happen.");
279}
280
281/*
282 * NMI exception handler.
283 */
284void nmi_exception_handler(struct pt_regs *regs)
285{
286	die_if_kernel("nmi_exception_handler execution Exception", regs);
287	die("NMI", regs);
288}
289
290/* Install CPU exception handler */
291void *set_except_vector(int n, void *addr)
292{
293	unsigned long handler = (unsigned long) addr;
294	unsigned long old_handler = exception_handlers[n];
295
296	exception_handlers[n] = handler;
297	return (void *)old_handler;
298}
299
300void __init trap_init(void)
301{
302	int i;
303
304	pgd_current = (unsigned long)init_mm.pgd;
305	/* DEBUG EXCEPTION */
306	memcpy((void *)DEBUG_VECTOR_BASE_ADDR,
307			&debug_exception_vector, DEBUG_VECTOR_SIZE);
308	/* NMI EXCEPTION */
309	memcpy((void *)GENERAL_VECTOR_BASE_ADDR,
310			&general_exception_vector, GENERAL_VECTOR_SIZE);
311
312	/*
313	 * Initialise exception handlers
314	 */
315	for (i = 0; i <= 31; i++)
316		set_except_vector(i, handle_reserved);
317
318	set_except_vector(1, handle_nmi);
319	set_except_vector(2, handle_adelinsn);
320	set_except_vector(3, handle_tlb_refill);
321	set_except_vector(4, handle_tlb_invaild);
322	set_except_vector(5, handle_ibe);
323	set_except_vector(6, handle_pel);
324	set_except_vector(7, handle_sys);
325	set_except_vector(8, handle_ccu);
326	set_except_vector(9, handle_ri);
327	set_except_vector(10, handle_tr);
328	set_except_vector(11, handle_adedata);
329	set_except_vector(12, handle_adedata);
330	set_except_vector(13, handle_tlb_refill);
331	set_except_vector(14, handle_tlb_invaild);
332	set_except_vector(15, handle_mod);
333	set_except_vector(16, handle_cee);
334	set_except_vector(17, handle_cpe);
335	set_except_vector(18, handle_dbe);
336	flush_icache_range(DEBUG_VECTOR_BASE_ADDR, IRQ_VECTOR_BASE_ADDR);
337
338	atomic_inc(&init_mm.mm_count);
339	current->active_mm = &init_mm;
340	cpu_cache_init();
341}
342