1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2021 ARM Limited
4 *
5 * Verify that the streaming SVE register context in signal frames is
6 * set up as 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 * 64];
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 SVE_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		/* Did we find the lowest supported VL? */
38		if (vq < sve_vq_from_vl(vl))
39			break;
40
41		/* Skip missing VLs */
42		vq = sve_vq_from_vl(vl);
43
44		vls[nvls++] = vl;
45	}
46
47	/* We need at least one VL */
48	if (nvls < 1) {
49		fprintf(stderr, "Only %d VL supported\n", nvls);
50		return false;
51	}
52
53	return true;
54}
55
56static void setup_ssve_regs(void)
57{
58	/* smstart sm; real data is TODO */
59	asm volatile(".inst 0xd503437f" : : : );
60}
61
62static int do_one_sme_vl(struct tdescr *td, siginfo_t *si, ucontext_t *uc,
63			 unsigned int vl)
64{
65	size_t offset;
66	struct _aarch64_ctx *head = GET_BUF_RESV_HEAD(context);
67	struct sve_context *ssve;
68	int ret;
69
70	fprintf(stderr, "Testing VL %d\n", vl);
71
72	ret = prctl(PR_SME_SET_VL, vl);
73	if (ret != vl) {
74		fprintf(stderr, "Failed to set VL, got %d\n", ret);
75		return 1;
76	}
77
78	/*
79	 * Get a signal context which should have a SVE frame and registers
80	 * in it.
81	 */
82	setup_ssve_regs();
83	if (!get_current_context(td, &context.uc, sizeof(context)))
84		return 1;
85
86	head = get_header(head, SVE_MAGIC, GET_BUF_RESV_SIZE(context),
87			  &offset);
88	if (!head) {
89		fprintf(stderr, "No SVE context\n");
90		return 1;
91	}
92
93	ssve = (struct sve_context *)head;
94	if (ssve->vl != vl) {
95		fprintf(stderr, "Got VL %d, expected %d\n", ssve->vl, vl);
96		return 1;
97	}
98
99	if (!(ssve->flags & SVE_SIG_FLAG_SM)) {
100		fprintf(stderr, "SVE_SIG_FLAG_SM not set in SVE record\n");
101		return 1;
102	}
103
104	/* The actual size validation is done in get_current_context() */
105	fprintf(stderr, "Got expected size %u and VL %d\n",
106		head->size, ssve->vl);
107
108	return 0;
109}
110
111static int sme_regs(struct tdescr *td, siginfo_t *si, ucontext_t *uc)
112{
113	int i;
114
115	for (i = 0; i < nvls; i++) {
116		if (do_one_sme_vl(td, si, uc, vls[i]))
117			return 1;
118	}
119
120	td->pass = 1;
121
122	return 0;
123}
124
125struct tdescr tde = {
126	.name = "Streaming SVE registers",
127	.descr = "Check that we get the right Streaming SVE registers reported",
128	.feats_required = FEAT_SME,
129	.timeout = 3,
130	.init = sme_get_vls,
131	.run = sme_regs,
132};
133