1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2023 ARM Limited
4 *
5 * Verify that the TPIDR2 register context in signal frames is restored.
6 */
7
8#include <signal.h>
9#include <ucontext.h>
10#include <sys/auxv.h>
11#include <sys/prctl.h>
12#include <unistd.h>
13#include <asm/sigcontext.h>
14
15#include "test_signals_utils.h"
16#include "testcases.h"
17
18#define SYS_TPIDR2 "S3_3_C13_C0_5"
19
20static uint64_t get_tpidr2(void)
21{
22 uint64_t val;
23
24 asm volatile (
25 "mrs %0, " SYS_TPIDR2 "\n"
26 : "=r"(val)
27 :
28 : "cc");
29
30 return val;
31}
32
33static void set_tpidr2(uint64_t val)
34{
35 asm volatile (
36 "msr " SYS_TPIDR2 ", %0\n"
37 :
38 : "r"(val)
39 : "cc");
40}
41
42
43static uint64_t initial_tpidr2;
44
45static bool save_tpidr2(struct tdescr *td)
46{
47 initial_tpidr2 = get_tpidr2();
48 fprintf(stderr, "Initial TPIDR2: %lx\n", initial_tpidr2);
49
50 return true;
51}
52
53static int modify_tpidr2(struct tdescr *td, siginfo_t *si, ucontext_t *uc)
54{
55 uint64_t my_tpidr2 = get_tpidr2();
56
57 my_tpidr2++;
58 fprintf(stderr, "Setting TPIDR2 to %lx\n", my_tpidr2);
59 set_tpidr2(my_tpidr2);
60
61 return 0;
62}
63
64static void check_tpidr2(struct tdescr *td)
65{
66 uint64_t tpidr2 = get_tpidr2();
67
68 td->pass = tpidr2 == initial_tpidr2;
69
70 if (td->pass)
71 fprintf(stderr, "TPIDR2 restored\n");
72 else
73 fprintf(stderr, "TPIDR2 was %lx but is now %lx\n",
74 initial_tpidr2, tpidr2);
75}
76
77struct tdescr tde = {
78 .name = "TPIDR2 restore",
79 .descr = "Validate that TPIDR2 is restored from the sigframe",
80 .feats_required = FEAT_SME,
81 .timeout = 3,
82 .sig_trig = SIGUSR1,
83 .init = save_tpidr2,
84 .run = modify_tpidr2,
85 .check_result = check_tpidr2,
86};
87

source code of linux/tools/testing/selftests/arm64/signal/testcases/tpidr2_restore.c