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 <signal.h>
10#include <ucontext.h>
11#include <sys/prctl.h>
12
13#include "test_signals_utils.h"
14#include "testcases.h"
15
16static union {
17	ucontext_t uc;
18	char buf[1024 * 128];
19} context;
20static unsigned int vls[SVE_VQ_MAX];
21unsigned int nvls = 0;
22
23static bool sme_get_vls(struct tdescr *td)
24{
25	int vq, vl;
26
27	/*
28	 * Enumerate up to SME_VQ_MAX vector lengths
29	 */
30	for (vq = SVE_VQ_MAX; vq > 0; --vq) {
31		vl = prctl(PR_SME_SET_VL, vq * 16);
32		if (vl == -1)
33			return false;
34
35		vl &= PR_SME_VL_LEN_MASK;
36
37		/* Skip missing VLs */
38		vq = sve_vq_from_vl(vl);
39
40		vls[nvls++] = vl;
41	}
42
43	/* We need at least one VL */
44	if (nvls < 1) {
45		fprintf(stderr, "Only %d VL supported\n", nvls);
46		return false;
47	}
48
49	return true;
50}
51
52static int do_one_sme_vl(struct tdescr *td, siginfo_t *si, ucontext_t *uc,
53			 unsigned int vl)
54{
55	size_t offset;
56	struct _aarch64_ctx *head = GET_BUF_RESV_HEAD(context);
57	struct za_context *za;
58
59	fprintf(stderr, "Testing VL %d\n", vl);
60
61	if (prctl(PR_SME_SET_VL, vl) != vl) {
62		fprintf(stderr, "Failed to set VL\n");
63		return 1;
64	}
65
66	/*
67	 * Get a signal context which should have a SVE frame and registers
68	 * in it.
69	 */
70	if (!get_current_context(td, &context.uc, sizeof(context)))
71		return 1;
72
73	head = get_header(head, ZA_MAGIC, GET_BUF_RESV_SIZE(context), &offset);
74	if (!head) {
75		fprintf(stderr, "No ZA context\n");
76		return 1;
77	}
78
79	za = (struct za_context *)head;
80	if (za->vl != vl) {
81		fprintf(stderr, "Got VL %d, expected %d\n", za->vl, vl);
82		return 1;
83	}
84
85	if (head->size != ZA_SIG_REGS_OFFSET) {
86		fprintf(stderr, "Context size %u, expected %lu\n",
87			head->size, ZA_SIG_REGS_OFFSET);
88		return 1;
89	}
90
91	/* The actual size validation is done in get_current_context() */
92	fprintf(stderr, "Got expected size %u and VL %d\n",
93		head->size, za->vl);
94
95	return 0;
96}
97
98static int sme_regs(struct tdescr *td, siginfo_t *si, ucontext_t *uc)
99{
100	int i;
101
102	for (i = 0; i < nvls; i++) {
103		if (do_one_sme_vl(td, si, uc, vls[i]))
104			return 1;
105	}
106
107	td->pass = 1;
108
109	return 0;
110}
111
112struct tdescr tde = {
113	.name = "ZA registers - ZA disabled",
114	.descr = "Check ZA context with ZA disabled",
115	.feats_required = FEAT_SME,
116	.timeout = 3,
117	.init = sme_get_vls,
118	.run = sme_regs,
119};
120