summaryrefslogtreecommitdiff
path: root/arch/powerpc/lib/test_emulate_step.c
blob: 6c47daa616149f745bf96702157ed9a38405437a (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
/*
 * Simple sanity test for emulate_step load/store instructions.
 *
 * Copyright IBM Corp. 2016
 *
 * This program is free software;  you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */

#define pr_fmt(fmt) "emulate_step_test: " fmt

#include <linux/ptrace.h>
#include <asm/sstep.h>
#include <asm/ppc-opcode.h>

#define IMM_L(i)		((uintptr_t)(i) & 0xffff)

/*
 * Defined with TEST_ prefix so it does not conflict with other
 * definitions.
 */
#define TEST_LD(r, base, i)	(PPC_INST_LD | ___PPC_RT(r) |		\
					___PPC_RA(base) | IMM_L(i))
#define TEST_LWZ(r, base, i)	(PPC_INST_LWZ | ___PPC_RT(r) |		\
					___PPC_RA(base) | IMM_L(i))
#define TEST_LWZX(t, a, b)	(PPC_INST_LWZX | ___PPC_RT(t) |		\
					___PPC_RA(a) | ___PPC_RB(b))
#define TEST_STD(r, base, i)	(PPC_INST_STD | ___PPC_RS(r) |		\
					___PPC_RA(base) | ((i) & 0xfffc))
#define TEST_LDARX(t, a, b, eh)	(PPC_INST_LDARX | ___PPC_RT(t) |	\
					___PPC_RA(a) | ___PPC_RB(b) |	\
					__PPC_EH(eh))
#define TEST_STDCX(s, a, b)	(PPC_INST_STDCX | ___PPC_RS(s) |	\
					___PPC_RA(a) | ___PPC_RB(b))
#define TEST_LFSX(t, a, b)	(PPC_INST_LFSX | ___PPC_RT(t) |		\
					___PPC_RA(a) | ___PPC_RB(b))
#define TEST_STFSX(s, a, b)	(PPC_INST_STFSX | ___PPC_RS(s) |	\
					___PPC_RA(a) | ___PPC_RB(b))
#define TEST_LFDX(t, a, b)	(PPC_INST_LFDX | ___PPC_RT(t) |		\
					___PPC_RA(a) | ___PPC_RB(b))
#define TEST_STFDX(s, a, b)	(PPC_INST_STFDX | ___PPC_RS(s) |	\
					___PPC_RA(a) | ___PPC_RB(b))
#define TEST_LVX(t, a, b)	(PPC_INST_LVX | ___PPC_RT(t) |		\
					___PPC_RA(a) | ___PPC_RB(b))
#define TEST_STVX(s, a, b)	(PPC_INST_STVX | ___PPC_RS(s) |		\
					___PPC_RA(a) | ___PPC_RB(b))
#define TEST_LXVD2X(s, a, b)	(PPC_INST_LXVD2X | VSX_XX1((s), R##a, R##b))
#define TEST_STXVD2X(s, a, b)	(PPC_INST_STXVD2X | VSX_XX1((s), R##a, R##b))


static void __init init_pt_regs(struct pt_regs *regs)
{
	static unsigned long msr;
	static bool msr_cached;

	memset(regs, 0, sizeof(struct pt_regs));

	if (likely(msr_cached)) {
		regs->msr = msr;
		return;
	}

	asm volatile("mfmsr %0" : "=r"(regs->msr));

	regs->msr |= MSR_FP;
	regs->msr |= MSR_VEC;
	regs->msr |= MSR_VSX;

	msr = regs->msr;
	msr_cached = true;
}

static void __init show_result(char *ins, char *result)
{
	pr_info("%-14s : %s\n", ins, result);
}

static void __init test_ld(void)
{
	struct pt_regs regs;
	unsigned long a = 0x23;
	int stepped = -1;

	init_pt_regs(&regs);
	regs.gpr[3] = (unsigned long) &a;

	/* ld r5, 0(r3) */
	stepped = emulate_step(&regs, TEST_LD(5, 3, 0));

	if (stepped == 1 && regs.gpr[5] == a)
		show_result("ld", "PASS");
	else
		show_result("ld", "FAIL");
}

static void __init test_lwz(void)
{
	struct pt_regs regs;
	unsigned int a = 0x4545;
	int stepped = -1;

	init_pt_regs(&regs);
	regs.gpr[3] = (unsigned long) &a;

	/* lwz r5, 0(r3) */
	stepped = emulate_step(&regs, TEST_LWZ(5, 3, 0));

	if (stepped == 1 && regs.gpr[5] == a)
		show_result("lwz", "PASS");
	else
		show_result("lwz", "FAIL");
}

static void __init test_lwzx(void)
{
	struct pt_regs regs;
	unsigned int a[3] = {0x0, 0x0, 0x1234};
	int stepped = -1;

	init_pt_regs(&regs);
	regs.gpr[3] = (unsigned long) a;
	regs.gpr[4] = 8;
	regs.gpr[5] = 0x8765;

	/* lwzx r5, r3, r4 */
	stepped = emulate_step(&regs, TEST_LWZX(5, 3, 4));
	if (stepped == 1 && regs.gpr[5] == a[2])
		show_result("lwzx", "PASS");
	else
		show_result("lwzx", "FAIL");
}

static void __init test_std(void)
{
	struct pt_regs regs;
	unsigned long a = 0x1234;
	int stepped = -1;

	init_pt_regs(&regs);
	regs.gpr[3] = (unsigned long) &a;
	regs.gpr[5] = 0x5678;

	/* std r5, 0(r3) */
	stepped = emulate_step(&regs, TEST_STD(5, 3, 0));
	if (stepped == 1 || regs.gpr[5] == a)
		show_result("std", "PASS");
	else
		show_result("std", "FAIL");
}

static void __init test_ldarx_stdcx(void)
{
	struct pt_regs regs;
	unsigned long a = 0x1234;
	int stepped = -1;
	unsigned long cr0_eq = 0x1 << 29; /* eq bit of CR0 */

	init_pt_regs(&regs);
	asm volatile("mfcr %0" : "=r"(regs.ccr));


	/*** ldarx ***/

	regs.gpr[3] = (unsigned long) &a;
	regs.gpr[4] = 0;
	regs.gpr[5] = 0x5678;

	/* ldarx r5, r3, r4, 0 */
	stepped = emulate_step(&regs, TEST_LDARX(5, 3, 4, 0));

	/*
	 * Don't touch 'a' here. Touching 'a' can do Load/store
	 * of 'a' which result in failure of subsequent stdcx.
	 * Instead, use hardcoded value for comparison.
	 */
	if (stepped <= 0 || regs.gpr[5] != 0x1234) {
		show_result("ldarx / stdcx.", "FAIL (ldarx)");
		return;
	}


	/*** stdcx. ***/

	regs.gpr[5] = 0x9ABC;

	/* stdcx. r5, r3, r4 */
	stepped = emulate_step(&regs, TEST_STDCX(5, 3, 4));

	/*
	 * Two possible scenarios that indicates successful emulation
	 * of stdcx. :
	 *  1. Reservation is active and store is performed. In this
	 *     case cr0.eq bit will be set to 1.
	 *  2. Reservation is not active and store is not performed.
	 *     In this case cr0.eq bit will be set to 0.
	 */
	if (stepped == 1 && ((regs.gpr[5] == a && (regs.ccr & cr0_eq))
			|| (regs.gpr[5] != a && !(regs.ccr & cr0_eq))))
		show_result("ldarx / stdcx.", "PASS");
	else
		show_result("ldarx / stdcx.", "FAIL (stdcx.)");
}

#ifdef CONFIG_PPC_FPU
static void __init test_lfsx_stfsx(void)
{
	struct pt_regs regs;
	union {
		float a;
		int b;
	} c;
	int cached_b;
	int stepped = -1;

	init_pt_regs(&regs);


	/*** lfsx ***/

	c.a = 123.45;
	cached_b = c.b;

	regs.gpr[3] = (unsigned long) &c.a;
	regs.gpr[4] = 0;

	/* lfsx frt10, r3, r4 */
	stepped = emulate_step(&regs, TEST_LFSX(10, 3, 4));

	if (stepped == 1)
		show_result("lfsx", "PASS");
	else
		show_result("lfsx", "FAIL");


	/*** stfsx ***/

	c.a = 678.91;

	/* stfsx frs10, r3, r4 */
	stepped = emulate_step(&regs, TEST_STFSX(10, 3, 4));

	if (stepped == 1 && c.b == cached_b)
		show_result("stfsx", "PASS");
	else
		show_result("stfsx", "FAIL");
}

static void __init test_lfdx_stfdx(void)
{
	struct pt_regs regs;
	union {
		double a;
		long b;
	} c;
	long cached_b;
	int stepped = -1;

	init_pt_regs(&regs);


	/*** lfdx ***/

	c.a = 123456.78;
	cached_b = c.b;

	regs.gpr[3] = (unsigned long) &c.a;
	regs.gpr[4] = 0;

	/* lfdx frt10, r3, r4 */
	stepped = emulate_step(&regs, TEST_LFDX(10, 3, 4));

	if (stepped == 1)
		show_result("lfdx", "PASS");
	else
		show_result("lfdx", "FAIL");


	/*** stfdx ***/

	c.a = 987654.32;

	/* stfdx frs10, r3, r4 */
	stepped = emulate_step(&regs, TEST_STFDX(10, 3, 4));

	if (stepped == 1 && c.b == cached_b)
		show_result("stfdx", "PASS");
	else
		show_result("stfdx", "FAIL");
}
#else
static void __init test_lfsx_stfsx(void)
{
	show_result("lfsx", "SKIP (CONFIG_PPC_FPU is not set)");
	show_result("stfsx", "SKIP (CONFIG_PPC_FPU is not set)");
}

static void __init test_lfdx_stfdx(void)
{
	show_result("lfdx", "SKIP (CONFIG_PPC_FPU is not set)");
	show_result("stfdx", "SKIP (CONFIG_PPC_FPU is not set)");
}
#endif /* CONFIG_PPC_FPU */

#ifdef CONFIG_ALTIVEC
static void __init test_lvx_stvx(void)
{
	struct pt_regs regs;
	union {
		vector128 a;
		u32 b[4];
	} c;
	u32 cached_b[4];
	int stepped = -1;

	init_pt_regs(&regs);


	/*** lvx ***/

	cached_b[0] = c.b[0] = 923745;
	cached_b[1] = c.b[1] = 2139478;
	cached_b[2] = c.b[2] = 9012;
	cached_b[3] = c.b[3] = 982134;

	regs.gpr[3] = (unsigned long) &c.a;
	regs.gpr[4] = 0;

	/* lvx vrt10, r3, r4 */
	stepped = emulate_step(&regs, TEST_LVX(10, 3, 4));

	if (stepped == 1)
		show_result("lvx", "PASS");
	else
		show_result("lvx", "FAIL");


	/*** stvx ***/

	c.b[0] = 4987513;
	c.b[1] = 84313948;
	c.b[2] = 71;
	c.b[3] = 498532;

	/* stvx vrs10, r3, r4 */
	stepped = emulate_step(&regs, TEST_STVX(10, 3, 4));

	if (stepped == 1 && cached_b[0] == c.b[0] && cached_b[1] == c.b[1] &&
	    cached_b[2] == c.b[2] && cached_b[3] == c.b[3])
		show_result("stvx", "PASS");
	else
		show_result("stvx", "FAIL");
}
#else
static void __init test_lvx_stvx(void)
{
	show_result("lvx", "SKIP (CONFIG_ALTIVEC is not set)");
	show_result("stvx", "SKIP (CONFIG_ALTIVEC is not set)");
}
#endif /* CONFIG_ALTIVEC */

#ifdef CONFIG_VSX
static void __init test_lxvd2x_stxvd2x(void)
{
	struct pt_regs regs;
	union {
		vector128 a;
		u32 b[4];
	} c;
	u32 cached_b[4];
	int stepped = -1;

	init_pt_regs(&regs);


	/*** lxvd2x ***/

	cached_b[0] = c.b[0] = 18233;
	cached_b[1] = c.b[1] = 34863571;
	cached_b[2] = c.b[2] = 834;
	cached_b[3] = c.b[3] = 6138911;

	regs.gpr[3] = (unsigned long) &c.a;
	regs.gpr[4] = 0;

	/* lxvd2x vsr39, r3, r4 */
	stepped = emulate_step(&regs, TEST_LXVD2X(39, 3, 4));

	if (stepped == 1 && cpu_has_feature(CPU_FTR_VSX)) {
		show_result("lxvd2x", "PASS");
	} else {
		if (!cpu_has_feature(CPU_FTR_VSX))
			show_result("lxvd2x", "PASS (!CPU_FTR_VSX)");
		else
			show_result("lxvd2x", "FAIL");
	}


	/*** stxvd2x ***/

	c.b[0] = 21379463;
	c.b[1] = 87;
	c.b[2] = 374234;
	c.b[3] = 4;

	/* stxvd2x vsr39, r3, r4 */
	stepped = emulate_step(&regs, TEST_STXVD2X(39, 3, 4));

	if (stepped == 1 && cached_b[0] == c.b[0] && cached_b[1] == c.b[1] &&
	    cached_b[2] == c.b[2] && cached_b[3] == c.b[3] &&
	    cpu_has_feature(CPU_FTR_VSX)) {
		show_result("stxvd2x", "PASS");
	} else {
		if (!cpu_has_feature(CPU_FTR_VSX))
			show_result("stxvd2x", "PASS (!CPU_FTR_VSX)");
		else
			show_result("stxvd2x", "FAIL");
	}
}
#else
static void __init test_lxvd2x_stxvd2x(void)
{
	show_result("lxvd2x", "SKIP (CONFIG_VSX is not set)");
	show_result("stxvd2x", "SKIP (CONFIG_VSX is not set)");
}
#endif /* CONFIG_VSX */

static int __init test_emulate_step(void)
{
	test_ld();
	test_lwz();
	test_lwzx();
	test_std();
	test_ldarx_stdcx();
	test_lfsx_stfsx();
	test_lfdx_stfdx();
	test_lvx_stvx();
	test_lxvd2x_stxvd2x();

	return 0;
}
late_initcall(test_emulate_step);