1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2021 ARM Limited
4 *
5 * Verify that the ZA register context in signal frames is set up as
6 * expected.
7 */
8
9#include <kselftest.h>
10#include <signal.h>
11#include <ucontext.h>
12#include <sys/prctl.h>
13
14#include "test_signals_utils.h"
15#include "sve_helpers.h"
16#include "testcases.h"
17
18static union {
19 ucontext_t uc;
20 char buf[1024 * 128];
21} context;
22
23static bool sme_get_vls(struct tdescr *td)
24{
25 int res = sve_fill_vls(VLS_USE_SME, 1);
26
27 if (!res)
28 return true;
29
30 if (res == KSFT_SKIP)
31 td->result = KSFT_SKIP;
32
33 return false;
34}
35
36static void setup_za_regs(void)
37{
38 /* smstart za; real data is TODO */
39 asm volatile(".inst 0xd503457f" : : : );
40}
41
42static char zeros[ZA_SIG_REGS_SIZE(SVE_VQ_MAX)];
43
44static int do_one_sme_vl(struct tdescr *td, siginfo_t *si, ucontext_t *uc,
45 unsigned int vl)
46{
47 size_t offset;
48 struct _aarch64_ctx *head = GET_BUF_RESV_HEAD(context);
49 struct za_context *za;
50
51 fprintf(stderr, "Testing VL %d\n", vl);
52
53 if (prctl(PR_SME_SET_VL, vl) != vl) {
54 fprintf(stderr, "Failed to set VL\n");
55 return 1;
56 }
57
58 /*
59 * Get a signal context which should have a SVE frame and registers
60 * in it.
61 */
62 setup_za_regs();
63 if (!get_current_context(td, &context.uc, sizeof(context)))
64 return 1;
65
66 head = get_header(head, magic: ZA_MAGIC, GET_BUF_RESV_SIZE(context), offset: &offset);
67 if (!head) {
68 fprintf(stderr, "No ZA context\n");
69 return 1;
70 }
71
72 za = (struct za_context *)head;
73 if (za->vl != vl) {
74 fprintf(stderr, "Got VL %d, expected %d\n", za->vl, vl);
75 return 1;
76 }
77
78 if (head->size != ZA_SIG_CONTEXT_SIZE(sve_vq_from_vl(vl))) {
79 fprintf(stderr, "ZA context size %u, expected %lu\n",
80 head->size, ZA_SIG_CONTEXT_SIZE(sve_vq_from_vl(vl)));
81 return 1;
82 }
83
84 fprintf(stderr, "Got expected size %u and VL %d\n",
85 head->size, za->vl);
86
87 /* We didn't load any data into ZA so it should be all zeros */
88 if (memcmp(zeros, (char *)za + ZA_SIG_REGS_OFFSET,
89 ZA_SIG_REGS_SIZE(sve_vq_from_vl(za->vl))) != 0) {
90 fprintf(stderr, "ZA data invalid\n");
91 return 1;
92 }
93
94 if (get_svcr() != 0) {
95 fprintf(stderr, "Unexpected SVCR %lx\n", get_svcr());
96 return 1;
97 }
98
99 return 0;
100}
101
102static int sme_regs(struct tdescr *td, siginfo_t *si, ucontext_t *uc)
103{
104 int i;
105
106 for (i = 0; i < nvls; i++) {
107 if (do_one_sme_vl(td, si, uc, vls[i]))
108 return 1;
109 }
110
111 td->pass = 1;
112
113 return 0;
114}
115
116struct tdescr tde = {
117 .name = "ZA register",
118 .descr = "Check that we get the right ZA registers reported",
119 .feats_required = FEAT_SME,
120 .timeout = 3,
121 .init = sme_get_vls,
122 .run = sme_regs,
123};
124

source code of linux/tools/testing/selftests/arm64/signal/testcases/za_regs.c