xref: /openbmc/linux/tools/testing/selftests/arm64/signal/testcases/tpidr2_siginfo.c (revision 9a87ffc99ec8eb8d35eed7c4f816d75f5cc9662e)
1*8ced9280SMark Brown // SPDX-License-Identifier: GPL-2.0
2*8ced9280SMark Brown /*
3*8ced9280SMark Brown  * Copyright (C) 2022 ARM Limited
4*8ced9280SMark Brown  *
5*8ced9280SMark Brown  * Verify that the TPIDR2 register context in signal frames is set up as
6*8ced9280SMark Brown  * expected.
7*8ced9280SMark Brown  */
8*8ced9280SMark Brown 
9*8ced9280SMark Brown #include <signal.h>
10*8ced9280SMark Brown #include <ucontext.h>
11*8ced9280SMark Brown #include <sys/auxv.h>
12*8ced9280SMark Brown #include <sys/prctl.h>
13*8ced9280SMark Brown #include <unistd.h>
14*8ced9280SMark Brown #include <asm/sigcontext.h>
15*8ced9280SMark Brown 
16*8ced9280SMark Brown #include "test_signals_utils.h"
17*8ced9280SMark Brown #include "testcases.h"
18*8ced9280SMark Brown 
19*8ced9280SMark Brown static union {
20*8ced9280SMark Brown 	ucontext_t uc;
21*8ced9280SMark Brown 	char buf[1024 * 128];
22*8ced9280SMark Brown } context;
23*8ced9280SMark Brown 
24*8ced9280SMark Brown #define SYS_TPIDR2 "S3_3_C13_C0_5"
25*8ced9280SMark Brown 
get_tpidr2(void)26*8ced9280SMark Brown static uint64_t get_tpidr2(void)
27*8ced9280SMark Brown {
28*8ced9280SMark Brown 	uint64_t val;
29*8ced9280SMark Brown 
30*8ced9280SMark Brown 	asm volatile (
31*8ced9280SMark Brown 		"mrs	%0, " SYS_TPIDR2 "\n"
32*8ced9280SMark Brown 		: "=r"(val)
33*8ced9280SMark Brown 		:
34*8ced9280SMark Brown 		: "cc");
35*8ced9280SMark Brown 
36*8ced9280SMark Brown 	return val;
37*8ced9280SMark Brown }
38*8ced9280SMark Brown 
tpidr2_present(struct tdescr * td,siginfo_t * si,ucontext_t * uc)39*8ced9280SMark Brown int tpidr2_present(struct tdescr *td, siginfo_t *si, ucontext_t *uc)
40*8ced9280SMark Brown {
41*8ced9280SMark Brown 	struct _aarch64_ctx *head = GET_BUF_RESV_HEAD(context);
42*8ced9280SMark Brown 	struct tpidr2_context *tpidr2_ctx;
43*8ced9280SMark Brown 	size_t offset;
44*8ced9280SMark Brown 	bool in_sigframe;
45*8ced9280SMark Brown 	bool have_sme;
46*8ced9280SMark Brown 	__u64 orig_tpidr2;
47*8ced9280SMark Brown 
48*8ced9280SMark Brown 	have_sme = getauxval(AT_HWCAP2) & HWCAP2_SME;
49*8ced9280SMark Brown 	if (have_sme)
50*8ced9280SMark Brown 		orig_tpidr2 = get_tpidr2();
51*8ced9280SMark Brown 
52*8ced9280SMark Brown 	if (!get_current_context(td, &context.uc, sizeof(context)))
53*8ced9280SMark Brown 		return 1;
54*8ced9280SMark Brown 
55*8ced9280SMark Brown 	tpidr2_ctx = (struct tpidr2_context *)
56*8ced9280SMark Brown 		get_header(head, TPIDR2_MAGIC, td->live_sz, &offset);
57*8ced9280SMark Brown 
58*8ced9280SMark Brown 	in_sigframe = tpidr2_ctx != NULL;
59*8ced9280SMark Brown 
60*8ced9280SMark Brown 	fprintf(stderr, "TPIDR2 sigframe %s on system %s SME\n",
61*8ced9280SMark Brown 		in_sigframe ? "present" : "absent",
62*8ced9280SMark Brown 		have_sme ? "with" : "without");
63*8ced9280SMark Brown 
64*8ced9280SMark Brown 	td->pass = (in_sigframe == have_sme);
65*8ced9280SMark Brown 
66*8ced9280SMark Brown 	/*
67*8ced9280SMark Brown 	 * Check that the value we read back was the one present at
68*8ced9280SMark Brown 	 * the time that the signal was triggered.  TPIDR2 is owned by
69*8ced9280SMark Brown 	 * libc so we can't safely choose the value and it is possible
70*8ced9280SMark Brown 	 * that we may need to revisit this in future if something
71*8ced9280SMark Brown 	 * starts deciding to set a new TPIDR2 between us reading and
72*8ced9280SMark Brown 	 * the signal.
73*8ced9280SMark Brown 	 */
74*8ced9280SMark Brown 	if (have_sme && tpidr2_ctx) {
75*8ced9280SMark Brown 		if (tpidr2_ctx->tpidr2 != orig_tpidr2) {
76*8ced9280SMark Brown 			fprintf(stderr, "TPIDR2 in frame is %llx, was %llx\n",
77*8ced9280SMark Brown 				tpidr2_ctx->tpidr2, orig_tpidr2);
78*8ced9280SMark Brown 			td->pass = false;
79*8ced9280SMark Brown 		}
80*8ced9280SMark Brown 	}
81*8ced9280SMark Brown 
82*8ced9280SMark Brown 	return 0;
83*8ced9280SMark Brown }
84*8ced9280SMark Brown 
85*8ced9280SMark Brown struct tdescr tde = {
86*8ced9280SMark Brown 	.name = "TPIDR2",
87*8ced9280SMark Brown 	.descr = "Validate that TPIDR2 is present as expected",
88*8ced9280SMark Brown 	.timeout = 3,
89*8ced9280SMark Brown 	.run = tpidr2_present,
90*8ced9280SMark Brown };
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