xref: /linux/tools/testing/selftests/arm64/fp/sve-probe-vls.c (revision 24168c5e6dfbdd5b414f048f47f75d64533296ca)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2015-2020 ARM Limited.
4  * Original author: Dave Martin <Dave.Martin@arm.com>
5  */
6 #include <assert.h>
7 #include <errno.h>
8 #include <stdio.h>
9 #include <stdlib.h>
10 #include <string.h>
11 #include <sys/auxv.h>
12 #include <sys/prctl.h>
13 #include <asm/sigcontext.h>
14 
15 #include "../../kselftest.h"
16 #include "rdvl.h"
17 
18 int main(int argc, char **argv)
19 {
20 	unsigned int vq;
21 	int vl;
22 	static unsigned int vqs[SVE_VQ_MAX];
23 	unsigned int nvqs = 0;
24 
25 	ksft_print_header();
26 	ksft_set_plan(2);
27 
28 	if (!(getauxval(AT_HWCAP) & HWCAP_SVE))
29 		ksft_exit_skip("SVE not available\n");
30 
31 	/*
32 	 * Enumerate up to SVE_VQ_MAX vector lengths
33 	 */
34 	for (vq = SVE_VQ_MAX; vq > 0; --vq) {
35 		vl = prctl(PR_SVE_SET_VL, vq * 16);
36 		if (vl == -1)
37 			ksft_exit_fail_msg("PR_SVE_SET_VL failed: %s (%d)\n",
38 					   strerror(errno), errno);
39 
40 		vl &= PR_SVE_VL_LEN_MASK;
41 
42 		if (rdvl_sve() != vl)
43 			ksft_exit_fail_msg("PR_SVE_SET_VL reports %d, RDVL %d\n",
44 					   vl, rdvl_sve());
45 
46 		if (!sve_vl_valid(vl))
47 			ksft_exit_fail_msg("VL %d invalid\n", vl);
48 		vq = sve_vq_from_vl(vl);
49 
50 		if (!(nvqs < SVE_VQ_MAX))
51 			ksft_exit_fail_msg("Too many VLs %u >= SVE_VQ_MAX\n",
52 					   nvqs);
53 		vqs[nvqs++] = vq;
54 	}
55 	ksft_test_result_pass("Enumerated %d vector lengths\n", nvqs);
56 	ksft_test_result_pass("All vector lengths valid\n");
57 
58 	/* Print out the vector lengths in ascending order: */
59 	while (nvqs--)
60 		ksft_print_msg("%u\n", 16 * vqs[nvqs]);
61 
62 	ksft_exit_pass();
63 }
64