summaryrefslogtreecommitdiff
path: root/arch/sh/kernel/process_64.c
blob: 056607185158b033be6239f94e1f268da42cc528 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
/*
 * arch/sh/kernel/process_64.c
 *
 * This file handles the architecture-dependent parts of process handling..
 *
 * Copyright (C) 2000, 2001  Paolo Alberelli
 * Copyright (C) 2003 - 2007  Paul Mundt
 * Copyright (C) 2003, 2004 Richard Curnow
 *
 * Started from SH3/4 version:
 *   Copyright (C) 1999, 2000  Niibe Yutaka & Kaz Kojima
 *
 *   In turn started from i386 version:
 *     Copyright (C) 1995  Linus Torvalds
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 */
#include <linux/mm.h>
#include <linux/fs.h>
#include <linux/ptrace.h>
#include <linux/reboot.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/io.h>
#include <linux/sched/debug.h>
#include <linux/sched/task.h>
#include <asm/syscalls.h>
#include <linux/uaccess.h>
#include <asm/pgtable.h>
#include <asm/mmu_context.h>
#include <asm/fpu.h>
#include <asm/switch_to.h>

struct task_struct *last_task_used_math = NULL;
struct pt_regs fake_swapper_regs = { 0, };

void show_regs(struct pt_regs *regs)
{
	unsigned long long ah, al, bh, bl, ch, cl;

	printk("\n");
	show_regs_print_info(KERN_DEFAULT);

	ah = (regs->pc) >> 32;
	al = (regs->pc) & 0xffffffff;
	bh = (regs->regs[18]) >> 32;
	bl = (regs->regs[18]) & 0xffffffff;
	ch = (regs->regs[15]) >> 32;
	cl = (regs->regs[15]) & 0xffffffff;
	printk("PC  : %08Lx%08Lx LINK: %08Lx%08Lx SP  : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->sr) >> 32;
	al = (regs->sr) & 0xffffffff;
        asm volatile ("getcon   " __TEA ", %0" : "=r" (bh));
        asm volatile ("getcon   " __TEA ", %0" : "=r" (bl));
	bh = (bh) >> 32;
	bl = (bl) & 0xffffffff;
        asm volatile ("getcon   " __KCR0 ", %0" : "=r" (ch));
        asm volatile ("getcon   " __KCR0 ", %0" : "=r" (cl));
	ch = (ch) >> 32;
	cl = (cl) & 0xffffffff;
	printk("SR  : %08Lx%08Lx TEA : %08Lx%08Lx KCR0: %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[0]) >> 32;
	al = (regs->regs[0]) & 0xffffffff;
	bh = (regs->regs[1]) >> 32;
	bl = (regs->regs[1]) & 0xffffffff;
	ch = (regs->regs[2]) >> 32;
	cl = (regs->regs[2]) & 0xffffffff;
	printk("R0  : %08Lx%08Lx R1  : %08Lx%08Lx R2  : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[3]) >> 32;
	al = (regs->regs[3]) & 0xffffffff;
	bh = (regs->regs[4]) >> 32;
	bl = (regs->regs[4]) & 0xffffffff;
	ch = (regs->regs[5]) >> 32;
	cl = (regs->regs[5]) & 0xffffffff;
	printk("R3  : %08Lx%08Lx R4  : %08Lx%08Lx R5  : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[6]) >> 32;
	al = (regs->regs[6]) & 0xffffffff;
	bh = (regs->regs[7]) >> 32;
	bl = (regs->regs[7]) & 0xffffffff;
	ch = (regs->regs[8]) >> 32;
	cl = (regs->regs[8]) & 0xffffffff;
	printk("R6  : %08Lx%08Lx R7  : %08Lx%08Lx R8  : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[9]) >> 32;
	al = (regs->regs[9]) & 0xffffffff;
	bh = (regs->regs[10]) >> 32;
	bl = (regs->regs[10]) & 0xffffffff;
	ch = (regs->regs[11]) >> 32;
	cl = (regs->regs[11]) & 0xffffffff;
	printk("R9  : %08Lx%08Lx R10 : %08Lx%08Lx R11 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[12]) >> 32;
	al = (regs->regs[12]) & 0xffffffff;
	bh = (regs->regs[13]) >> 32;
	bl = (regs->regs[13]) & 0xffffffff;
	ch = (regs->regs[14]) >> 32;
	cl = (regs->regs[14]) & 0xffffffff;
	printk("R12 : %08Lx%08Lx R13 : %08Lx%08Lx R14 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[16]) >> 32;
	al = (regs->regs[16]) & 0xffffffff;
	bh = (regs->regs[17]) >> 32;
	bl = (regs->regs[17]) & 0xffffffff;
	ch = (regs->regs[19]) >> 32;
	cl = (regs->regs[19]) & 0xffffffff;
	printk("R16 : %08Lx%08Lx R17 : %08Lx%08Lx R19 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[20]) >> 32;
	al = (regs->regs[20]) & 0xffffffff;
	bh = (regs->regs[21]) >> 32;
	bl = (regs->regs[21]) & 0xffffffff;
	ch = (regs->regs[22]) >> 32;
	cl = (regs->regs[22]) & 0xffffffff;
	printk("R20 : %08Lx%08Lx R21 : %08Lx%08Lx R22 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[23]) >> 32;
	al = (regs->regs[23]) & 0xffffffff;
	bh = (regs->regs[24]) >> 32;
	bl = (regs->regs[24]) & 0xffffffff;
	ch = (regs->regs[25]) >> 32;
	cl = (regs->regs[25]) & 0xffffffff;
	printk("R23 : %08Lx%08Lx R24 : %08Lx%08Lx R25 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[26]) >> 32;
	al = (regs->regs[26]) & 0xffffffff;
	bh = (regs->regs[27]) >> 32;
	bl = (regs->regs[27]) & 0xffffffff;
	ch = (regs->regs[28]) >> 32;
	cl = (regs->regs[28]) & 0xffffffff;
	printk("R26 : %08Lx%08Lx R27 : %08Lx%08Lx R28 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[29]) >> 32;
	al = (regs->regs[29]) & 0xffffffff;
	bh = (regs->regs[30]) >> 32;
	bl = (regs->regs[30]) & 0xffffffff;
	ch = (regs->regs[31]) >> 32;
	cl = (regs->regs[31]) & 0xffffffff;
	printk("R29 : %08Lx%08Lx R30 : %08Lx%08Lx R31 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[32]) >> 32;
	al = (regs->regs[32]) & 0xffffffff;
	bh = (regs->regs[33]) >> 32;
	bl = (regs->regs[33]) & 0xffffffff;
	ch = (regs->regs[34]) >> 32;
	cl = (regs->regs[34]) & 0xffffffff;
	printk("R32 : %08Lx%08Lx R33 : %08Lx%08Lx R34 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[35]) >> 32;
	al = (regs->regs[35]) & 0xffffffff;
	bh = (regs->regs[36]) >> 32;
	bl = (regs->regs[36]) & 0xffffffff;
	ch = (regs->regs[37]) >> 32;
	cl = (regs->regs[37]) & 0xffffffff;
	printk("R35 : %08Lx%08Lx R36 : %08Lx%08Lx R37 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[38]) >> 32;
	al = (regs->regs[38]) & 0xffffffff;
	bh = (regs->regs[39]) >> 32;
	bl = (regs->regs[39]) & 0xffffffff;
	ch = (regs->regs[40]) >> 32;
	cl = (regs->regs[40]) & 0xffffffff;
	printk("R38 : %08Lx%08Lx R39 : %08Lx%08Lx R40 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[41]) >> 32;
	al = (regs->regs[41]) & 0xffffffff;
	bh = (regs->regs[42]) >> 32;
	bl = (regs->regs[42]) & 0xffffffff;
	ch = (regs->regs[43]) >> 32;
	cl = (regs->regs[43]) & 0xffffffff;
	printk("R41 : %08Lx%08Lx R42 : %08Lx%08Lx R43 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[44]) >> 32;
	al = (regs->regs[44]) & 0xffffffff;
	bh = (regs->regs[45]) >> 32;
	bl = (regs->regs[45]) & 0xffffffff;
	ch = (regs->regs[46]) >> 32;
	cl = (regs->regs[46]) & 0xffffffff;
	printk("R44 : %08Lx%08Lx R45 : %08Lx%08Lx R46 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[47]) >> 32;
	al = (regs->regs[47]) & 0xffffffff;
	bh = (regs->regs[48]) >> 32;
	bl = (regs->regs[48]) & 0xffffffff;
	ch = (regs->regs[49]) >> 32;
	cl = (regs->regs[49]) & 0xffffffff;
	printk("R47 : %08Lx%08Lx R48 : %08Lx%08Lx R49 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[50]) >> 32;
	al = (regs->regs[50]) & 0xffffffff;
	bh = (regs->regs[51]) >> 32;
	bl = (regs->regs[51]) & 0xffffffff;
	ch = (regs->regs[52]) >> 32;
	cl = (regs->regs[52]) & 0xffffffff;
	printk("R50 : %08Lx%08Lx R51 : %08Lx%08Lx R52 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[53]) >> 32;
	al = (regs->regs[53]) & 0xffffffff;
	bh = (regs->regs[54]) >> 32;
	bl = (regs->regs[54]) & 0xffffffff;
	ch = (regs->regs[55]) >> 32;
	cl = (regs->regs[55]) & 0xffffffff;
	printk("R53 : %08Lx%08Lx R54 : %08Lx%08Lx R55 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[56]) >> 32;
	al = (regs->regs[56]) & 0xffffffff;
	bh = (regs->regs[57]) >> 32;
	bl = (regs->regs[57]) & 0xffffffff;
	ch = (regs->regs[58]) >> 32;
	cl = (regs->regs[58]) & 0xffffffff;
	printk("R56 : %08Lx%08Lx R57 : %08Lx%08Lx R58 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[59]) >> 32;
	al = (regs->regs[59]) & 0xffffffff;
	bh = (regs->regs[60]) >> 32;
	bl = (regs->regs[60]) & 0xffffffff;
	ch = (regs->regs[61]) >> 32;
	cl = (regs->regs[61]) & 0xffffffff;
	printk("R59 : %08Lx%08Lx R60 : %08Lx%08Lx R61 : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->regs[62]) >> 32;
	al = (regs->regs[62]) & 0xffffffff;
	bh = (regs->tregs[0]) >> 32;
	bl = (regs->tregs[0]) & 0xffffffff;
	ch = (regs->tregs[1]) >> 32;
	cl = (regs->tregs[1]) & 0xffffffff;
	printk("R62 : %08Lx%08Lx T0  : %08Lx%08Lx T1  : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->tregs[2]) >> 32;
	al = (regs->tregs[2]) & 0xffffffff;
	bh = (regs->tregs[3]) >> 32;
	bl = (regs->tregs[3]) & 0xffffffff;
	ch = (regs->tregs[4]) >> 32;
	cl = (regs->tregs[4]) & 0xffffffff;
	printk("T2  : %08Lx%08Lx T3  : %08Lx%08Lx T4  : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	ah = (regs->tregs[5]) >> 32;
	al = (regs->tregs[5]) & 0xffffffff;
	bh = (regs->tregs[6]) >> 32;
	bl = (regs->tregs[6]) & 0xffffffff;
	ch = (regs->tregs[7]) >> 32;
	cl = (regs->tregs[7]) & 0xffffffff;
	printk("T5  : %08Lx%08Lx T6  : %08Lx%08Lx T7  : %08Lx%08Lx\n",
	       ah, al, bh, bl, ch, cl);

	/*
	 * If we're in kernel mode, dump the stack too..
	 */
	if (!user_mode(regs)) {
		void show_stack(struct task_struct *tsk, unsigned long *sp);
		unsigned long sp = regs->regs[15] & 0xffffffff;
		struct task_struct *tsk = get_current();

		tsk->thread.kregs = regs;

		show_stack(tsk, (unsigned long *)sp);
	}
}

/*
 * Free current thread data structures etc..
 */
void exit_thread(struct task_struct *tsk)
{
	/*
	 * See arch/sparc/kernel/process.c for the precedent for doing
	 * this -- RPC.
	 *
	 * The SH-5 FPU save/restore approach relies on
	 * last_task_used_math pointing to a live task_struct.  When
	 * another task tries to use the FPU for the 1st time, the FPUDIS
	 * trap handling (see arch/sh/kernel/cpu/sh5/fpu.c) will save the
	 * existing FPU state to the FP regs field within
	 * last_task_used_math before re-loading the new task's FPU state
	 * (or initialising it if the FPU has been used before).  So if
	 * last_task_used_math is stale, and its page has already been
	 * re-allocated for another use, the consequences are rather
	 * grim. Unless we null it here, there is no other path through
	 * which it would get safely nulled.
	 */
#ifdef CONFIG_SH_FPU
	if (last_task_used_math == tsk)
		last_task_used_math = NULL;
#endif
}

void flush_thread(void)
{

	/* Called by fs/exec.c (setup_new_exec) to remove traces of a
	 * previously running executable. */
#ifdef CONFIG_SH_FPU
	if (last_task_used_math == current) {
		last_task_used_math = NULL;
	}
	/* Force FPU state to be reinitialised after exec */
	clear_used_math();
#endif

	/* if we are a kernel thread, about to change to user thread,
         * update kreg
         */
	if(current->thread.kregs==&fake_swapper_regs) {
          current->thread.kregs =
             ((struct pt_regs *)(THREAD_SIZE + (unsigned long) current) - 1);
	  current->thread.uregs = current->thread.kregs;
	}
}

void release_thread(struct task_struct *dead_task)
{
	/* do nothing */
}

/* Fill in the fpu structure for a core dump.. */
int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu)
{
#ifdef CONFIG_SH_FPU
	int fpvalid;
	struct task_struct *tsk = current;

	fpvalid = !!tsk_used_math(tsk);
	if (fpvalid) {
		if (current == last_task_used_math) {
			enable_fpu();
			save_fpu(tsk);
			disable_fpu();
			last_task_used_math = 0;
			regs->sr |= SR_FD;
		}

		memcpy(fpu, &tsk->thread.xstate->hardfpu, sizeof(*fpu));
	}

	return fpvalid;
#else
	return 0; /* Task didn't use the fpu at all. */
#endif
}
EXPORT_SYMBOL(dump_fpu);

asmlinkage void ret_from_fork(void);
asmlinkage void ret_from_kernel_thread(void);

int copy_thread(unsigned long clone_flags, unsigned long usp,
		unsigned long arg, struct task_struct *p)
{
	struct pt_regs *childregs;

#ifdef CONFIG_SH_FPU
	/* can't happen for a kernel thread */
	if (last_task_used_math == current) {
		enable_fpu();
		save_fpu(current);
		disable_fpu();
		last_task_used_math = NULL;
		current_pt_regs()->sr |= SR_FD;
	}
#endif
	/* Copy from sh version */
	childregs = (struct pt_regs *)(THREAD_SIZE + task_stack_page(p)) - 1;
	p->thread.sp = (unsigned long) childregs;

	if (unlikely(p->flags & PF_KTHREAD)) {
		memset(childregs, 0, sizeof(struct pt_regs));
		childregs->regs[2] = (unsigned long)arg;
		childregs->regs[3] = (unsigned long)usp;
		childregs->sr = (1 << 30); /* not user_mode */
		childregs->sr |= SR_FD; /* Invalidate FPU flag */
		p->thread.pc = (unsigned long) ret_from_kernel_thread;
		return 0;
	}
	*childregs = *current_pt_regs();

	/*
	 * Sign extend the edited stack.
	 * Note that thread.pc and thread.pc will stay
	 * 32-bit wide and context switch must take care
	 * of NEFF sign extension.
	 */
	if (usp)
		childregs->regs[15] = neff_sign_extend(usp);
	p->thread.uregs = childregs;

	childregs->regs[9] = 0; /* Set return value for child */
	childregs->sr |= SR_FD; /* Invalidate FPU flag */

	p->thread.pc = (unsigned long) ret_from_fork;

	return 0;
}

#ifdef CONFIG_FRAME_POINTER
static int in_sh64_switch_to(unsigned long pc)
{
	extern char __sh64_switch_to_end;
	/* For a sleeping task, the PC is somewhere in the middle of the function,
	   so we don't have to worry about masking the LSB off */
	return (pc >= (unsigned long) sh64_switch_to) &&
	       (pc < (unsigned long) &__sh64_switch_to_end);
}
#endif

unsigned long get_wchan(struct task_struct *p)
{
	unsigned long pc;

	if (!p || p == current || p->state == TASK_RUNNING)
		return 0;

	/*
	 * The same comment as on the Alpha applies here, too ...
	 */
	pc = thread_saved_pc(p);

#ifdef CONFIG_FRAME_POINTER
	if (in_sh64_switch_to(pc)) {
		unsigned long schedule_fp;
		unsigned long sh64_switch_to_fp;
		unsigned long schedule_caller_pc;

		sh64_switch_to_fp = (long) p->thread.sp;
		/* r14 is saved at offset 4 in the sh64_switch_to frame */
		schedule_fp = *(unsigned long *) (long)(sh64_switch_to_fp + 4);

		/* and the caller of 'schedule' is (currently!) saved at offset 24
		   in the frame of schedule (from disasm) */
		schedule_caller_pc = *(unsigned long *) (long)(schedule_fp + 24);
		return schedule_caller_pc;
	}
#endif
	return pc;
}