summaryrefslogtreecommitdiff
path: root/tools/testing/selftests/arm64/abi/syscall-abi.c
blob: dd7ebe536d05faec4cc7053ee10c9e39bf31e094 (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
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2021 ARM Limited.
 */

#include <errno.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/auxv.h>
#include <sys/prctl.h>
#include <asm/hwcap.h>
#include <asm/sigcontext.h>
#include <asm/unistd.h>

#include "../../kselftest.h"

#include "syscall-abi.h"

#define NUM_VL ((SVE_VQ_MAX - SVE_VQ_MIN) + 1)

static int default_sme_vl;

extern void do_syscall(int sve_vl, int sme_vl);

static void fill_random(void *buf, size_t size)
{
	int i;
	uint32_t *lbuf = buf;

	/* random() returns a 32 bit number regardless of the size of long */
	for (i = 0; i < size / sizeof(uint32_t); i++)
		lbuf[i] = random();
}

/*
 * We also repeat the test for several syscalls to try to expose different
 * behaviour.
 */
static struct syscall_cfg {
	int syscall_nr;
	const char *name;
} syscalls[] = {
	{ __NR_getpid,		"getpid()" },
	{ __NR_sched_yield,	"sched_yield()" },
};

#define NUM_GPR 31
uint64_t gpr_in[NUM_GPR];
uint64_t gpr_out[NUM_GPR];

static void setup_gpr(struct syscall_cfg *cfg, int sve_vl, int sme_vl,
		      uint64_t svcr)
{
	fill_random(gpr_in, sizeof(gpr_in));
	gpr_in[8] = cfg->syscall_nr;
	memset(gpr_out, 0, sizeof(gpr_out));
}

static int check_gpr(struct syscall_cfg *cfg, int sve_vl, int sme_vl, uint64_t svcr)
{
	int errors = 0;
	int i;

	/*
	 * GPR x0-x7 may be clobbered, and all others should be preserved.
	 */
	for (i = 9; i < ARRAY_SIZE(gpr_in); i++) {
		if (gpr_in[i] != gpr_out[i]) {
			ksft_print_msg("%s SVE VL %d mismatch in GPR %d: %llx != %llx\n",
				       cfg->name, sve_vl, i,
				       gpr_in[i], gpr_out[i]);
			errors++;
		}
	}

	return errors;
}

#define NUM_FPR 32
uint64_t fpr_in[NUM_FPR * 2];
uint64_t fpr_out[NUM_FPR * 2];

static void setup_fpr(struct syscall_cfg *cfg, int sve_vl, int sme_vl,
		      uint64_t svcr)
{
	fill_random(fpr_in, sizeof(fpr_in));
	memset(fpr_out, 0, sizeof(fpr_out));
}

static int check_fpr(struct syscall_cfg *cfg, int sve_vl, int sme_vl,
		     uint64_t svcr)
{
	int errors = 0;
	int i;

	if (!sve_vl) {
		for (i = 0; i < ARRAY_SIZE(fpr_in); i++) {
			if (fpr_in[i] != fpr_out[i]) {
				ksft_print_msg("%s Q%d/%d mismatch %llx != %llx\n",
					       cfg->name,
					       i / 2, i % 2,
					       fpr_in[i], fpr_out[i]);
				errors++;
			}
		}
	}

	return errors;
}

#define SVE_Z_SHARED_BYTES (128 / 8)

static uint8_t z_zero[__SVE_ZREG_SIZE(SVE_VQ_MAX)];
uint8_t z_in[SVE_NUM_ZREGS * __SVE_ZREG_SIZE(SVE_VQ_MAX)];
uint8_t z_out[SVE_NUM_ZREGS * __SVE_ZREG_SIZE(SVE_VQ_MAX)];

static void setup_z(struct syscall_cfg *cfg, int sve_vl, int sme_vl,
		    uint64_t svcr)
{
	fill_random(z_in, sizeof(z_in));
	fill_random(z_out, sizeof(z_out));
}

static int check_z(struct syscall_cfg *cfg, int sve_vl, int sme_vl,
		   uint64_t svcr)
{
	size_t reg_size = sve_vl;
	int errors = 0;
	int i;

	if (!sve_vl)
		return 0;

	for (i = 0; i < SVE_NUM_ZREGS; i++) {
		uint8_t *in = &z_in[reg_size * i];
		uint8_t *out = &z_out[reg_size * i];

		if (svcr & SVCR_SM_MASK) {
			/*
			 * In streaming mode the whole register should
			 * be cleared by the transition out of
			 * streaming mode.
			 */
			if (memcmp(z_zero, out, reg_size) != 0) {
				ksft_print_msg("%s SVE VL %d Z%d non-zero\n",
					       cfg->name, sve_vl, i);
				errors++;
			}
		} else {
			/*
			 * For standard SVE the low 128 bits should be
			 * preserved and any additional bits cleared.
			 */
			if (memcmp(in, out, SVE_Z_SHARED_BYTES) != 0) {
				ksft_print_msg("%s SVE VL %d Z%d low 128 bits changed\n",
					       cfg->name, sve_vl, i);
				errors++;
			}

			if (reg_size > SVE_Z_SHARED_BYTES &&
			    (memcmp(z_zero, out + SVE_Z_SHARED_BYTES,
				    reg_size - SVE_Z_SHARED_BYTES) != 0)) {
				ksft_print_msg("%s SVE VL %d Z%d high bits non-zero\n",
					       cfg->name, sve_vl, i);
				errors++;
			}
		}
	}

	return errors;
}

uint8_t p_in[SVE_NUM_PREGS * __SVE_PREG_SIZE(SVE_VQ_MAX)];
uint8_t p_out[SVE_NUM_PREGS * __SVE_PREG_SIZE(SVE_VQ_MAX)];

static void setup_p(struct syscall_cfg *cfg, int sve_vl, int sme_vl,
		    uint64_t svcr)
{
	fill_random(p_in, sizeof(p_in));
	fill_random(p_out, sizeof(p_out));
}

static int check_p(struct syscall_cfg *cfg, int sve_vl, int sme_vl,
		   uint64_t svcr)
{
	size_t reg_size = sve_vq_from_vl(sve_vl) * 2; /* 1 bit per VL byte */

	int errors = 0;
	int i;

	if (!sve_vl)
		return 0;

	/* After a syscall the P registers should be zeroed */
	for (i = 0; i < SVE_NUM_PREGS * reg_size; i++)
		if (p_out[i])
			errors++;
	if (errors)
		ksft_print_msg("%s SVE VL %d predicate registers non-zero\n",
			       cfg->name, sve_vl);

	return errors;
}

uint8_t ffr_in[__SVE_PREG_SIZE(SVE_VQ_MAX)];
uint8_t ffr_out[__SVE_PREG_SIZE(SVE_VQ_MAX)];

static void setup_ffr(struct syscall_cfg *cfg, int sve_vl, int sme_vl,
		      uint64_t svcr)
{
	/*
	 * If we are in streaming mode and do not have FA64 then FFR
	 * is unavailable.
	 */
	if ((svcr & SVCR_SM_MASK) &&
	    !(getauxval(AT_HWCAP2) & HWCAP2_SME_FA64)) {
		memset(&ffr_in, 0, sizeof(ffr_in));
		return;
	}

	/*
	 * It is only valid to set a contiguous set of bits starting
	 * at 0.  For now since we're expecting this to be cleared by
	 * a syscall just set all bits.
	 */
	memset(ffr_in, 0xff, sizeof(ffr_in));
	fill_random(ffr_out, sizeof(ffr_out));
}

static int check_ffr(struct syscall_cfg *cfg, int sve_vl, int sme_vl,
		     uint64_t svcr)
{
	size_t reg_size = sve_vq_from_vl(sve_vl) * 2;  /* 1 bit per VL byte */
	int errors = 0;
	int i;

	if (!sve_vl)
		return 0;

	if ((svcr & SVCR_SM_MASK) &&
	    !(getauxval(AT_HWCAP2) & HWCAP2_SME_FA64))
		return 0;

	/* After a syscall FFR should be zeroed */
	for (i = 0; i < reg_size; i++)
		if (ffr_out[i])
			errors++;
	if (errors)
		ksft_print_msg("%s SVE VL %d FFR non-zero\n",
			       cfg->name, sve_vl);

	return errors;
}

uint64_t svcr_in, svcr_out;

static void setup_svcr(struct syscall_cfg *cfg, int sve_vl, int sme_vl,
		    uint64_t svcr)
{
	svcr_in = svcr;
}

static int check_svcr(struct syscall_cfg *cfg, int sve_vl, int sme_vl,
		      uint64_t svcr)
{
	int errors = 0;

	if (svcr_out & SVCR_SM_MASK) {
		ksft_print_msg("%s Still in SM, SVCR %llx\n",
			       cfg->name, svcr_out);
		errors++;
	}

	if ((svcr_in & SVCR_ZA_MASK) != (svcr_out & SVCR_ZA_MASK)) {
		ksft_print_msg("%s PSTATE.ZA changed, SVCR %llx != %llx\n",
			       cfg->name, svcr_in, svcr_out);
		errors++;
	}

	return errors;
}

uint8_t za_in[SVE_NUM_PREGS * __SVE_ZREG_SIZE(SVE_VQ_MAX)];
uint8_t za_out[SVE_NUM_PREGS * __SVE_ZREG_SIZE(SVE_VQ_MAX)];

static void setup_za(struct syscall_cfg *cfg, int sve_vl, int sme_vl,
		     uint64_t svcr)
{
	fill_random(za_in, sizeof(za_in));
	memset(za_out, 0, sizeof(za_out));
}

static int check_za(struct syscall_cfg *cfg, int sve_vl, int sme_vl,
		    uint64_t svcr)
{
	size_t reg_size = sme_vl * sme_vl;
	int errors = 0;

	if (!(svcr & SVCR_ZA_MASK))
		return 0;

	if (memcmp(za_in, za_out, reg_size) != 0) {
		ksft_print_msg("SME VL %d ZA does not match\n", sme_vl);
		errors++;
	}

	return errors;
}

typedef void (*setup_fn)(struct syscall_cfg *cfg, int sve_vl, int sme_vl,
			 uint64_t svcr);
typedef int (*check_fn)(struct syscall_cfg *cfg, int sve_vl, int sme_vl,
			uint64_t svcr);

/*
 * Each set of registers has a setup function which is called before
 * the syscall to fill values in a global variable for loading by the
 * test code and a check function which validates that the results are
 * as expected.  Vector lengths are passed everywhere, a vector length
 * of 0 should be treated as do not test.
 */
static struct {
	setup_fn setup;
	check_fn check;
} regset[] = {
	{ setup_gpr, check_gpr },
	{ setup_fpr, check_fpr },
	{ setup_z, check_z },
	{ setup_p, check_p },
	{ setup_ffr, check_ffr },
	{ setup_svcr, check_svcr },
	{ setup_za, check_za },
};

static bool do_test(struct syscall_cfg *cfg, int sve_vl, int sme_vl,
		    uint64_t svcr)
{
	int errors = 0;
	int i;

	for (i = 0; i < ARRAY_SIZE(regset); i++)
		regset[i].setup(cfg, sve_vl, sme_vl, svcr);

	do_syscall(sve_vl, sme_vl);

	for (i = 0; i < ARRAY_SIZE(regset); i++)
		errors += regset[i].check(cfg, sve_vl, sme_vl, svcr);

	return errors == 0;
}

static void test_one_syscall(struct syscall_cfg *cfg)
{
	int sve_vq, sve_vl;
	int sme_vq, sme_vl;

	/* FPSIMD only case */
	ksft_test_result(do_test(cfg, 0, default_sme_vl, 0),
			 "%s FPSIMD\n", cfg->name);

	if (!(getauxval(AT_HWCAP) & HWCAP_SVE))
		return;

	for (sve_vq = SVE_VQ_MAX; sve_vq > 0; --sve_vq) {
		sve_vl = prctl(PR_SVE_SET_VL, sve_vq * 16);
		if (sve_vl == -1)
			ksft_exit_fail_msg("PR_SVE_SET_VL failed: %s (%d)\n",
					   strerror(errno), errno);

		sve_vl &= PR_SVE_VL_LEN_MASK;

		if (sve_vq != sve_vq_from_vl(sve_vl))
			sve_vq = sve_vq_from_vl(sve_vl);

		ksft_test_result(do_test(cfg, sve_vl, default_sme_vl, 0),
				 "%s SVE VL %d\n", cfg->name, sve_vl);

		if (!(getauxval(AT_HWCAP2) & HWCAP2_SME))
			continue;

		for (sme_vq = SVE_VQ_MAX; sme_vq > 0; --sme_vq) {
			sme_vl = prctl(PR_SME_SET_VL, sme_vq * 16);
			if (sme_vl == -1)
				ksft_exit_fail_msg("PR_SME_SET_VL failed: %s (%d)\n",
						   strerror(errno), errno);

			sme_vl &= PR_SME_VL_LEN_MASK;

			if (sme_vq != sve_vq_from_vl(sme_vl))
				sme_vq = sve_vq_from_vl(sme_vl);

			ksft_test_result(do_test(cfg, sve_vl, sme_vl,
						 SVCR_ZA_MASK | SVCR_SM_MASK),
					 "%s SVE VL %d/SME VL %d SM+ZA\n",
					 cfg->name, sve_vl, sme_vl);
			ksft_test_result(do_test(cfg, sve_vl, sme_vl,
						 SVCR_SM_MASK),
					 "%s SVE VL %d/SME VL %d SM\n",
					 cfg->name, sve_vl, sme_vl);
			ksft_test_result(do_test(cfg, sve_vl, sme_vl,
						 SVCR_ZA_MASK),
					 "%s SVE VL %d/SME VL %d ZA\n",
					 cfg->name, sve_vl, sme_vl);
		}
	}
}

int sve_count_vls(void)
{
	unsigned int vq;
	int vl_count = 0;
	int vl;

	if (!(getauxval(AT_HWCAP) & HWCAP_SVE))
		return 0;

	/*
	 * Enumerate up to SVE_VQ_MAX vector lengths
	 */
	for (vq = SVE_VQ_MAX; vq > 0; --vq) {
		vl = prctl(PR_SVE_SET_VL, vq * 16);
		if (vl == -1)
			ksft_exit_fail_msg("PR_SVE_SET_VL failed: %s (%d)\n",
					   strerror(errno), errno);

		vl &= PR_SVE_VL_LEN_MASK;

		if (vq != sve_vq_from_vl(vl))
			vq = sve_vq_from_vl(vl);

		vl_count++;
	}

	return vl_count;
}

int sme_count_vls(void)
{
	unsigned int vq;
	int vl_count = 0;
	int vl;

	if (!(getauxval(AT_HWCAP2) & HWCAP2_SME))
		return 0;

	/* Ensure we configure a SME VL, used to flag if SVCR is set */
	default_sme_vl = 16;

	/*
	 * Enumerate up to SVE_VQ_MAX vector lengths
	 */
	for (vq = SVE_VQ_MAX; vq > 0; --vq) {
		vl = prctl(PR_SME_SET_VL, vq * 16);
		if (vl == -1)
			ksft_exit_fail_msg("PR_SME_SET_VL failed: %s (%d)\n",
					   strerror(errno), errno);

		vl &= PR_SME_VL_LEN_MASK;

		if (vq != sve_vq_from_vl(vl))
			vq = sve_vq_from_vl(vl);

		vl_count++;
	}

	return vl_count;
}

int main(void)
{
	int i;
	int tests = 1;  /* FPSIMD */

	srandom(getpid());

	ksft_print_header();
	tests += sve_count_vls();
	tests += (sve_count_vls() * sme_count_vls()) * 3;
	ksft_set_plan(ARRAY_SIZE(syscalls) * tests);

	if (getauxval(AT_HWCAP2) & HWCAP2_SME_FA64)
		ksft_print_msg("SME with FA64\n");
	else if (getauxval(AT_HWCAP2) & HWCAP2_SME)
		ksft_print_msg("SME without FA64\n");

	for (i = 0; i < ARRAY_SIZE(syscalls); i++)
		test_one_syscall(&syscalls[i]);

	ksft_print_cnts();

	return 0;
}