1 files changed, 86 insertions, 0 deletions
diff --git a/tools/testing/selftests/arm64/signal/testcases/tpidr2_restore.c b/tools/testing/selftests/arm64/signal/testcases/tpidr2_restore.c
new file mode 100644
index 000000000000..f9a86c00c28c
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/testcases/tpidr2_restore.c
@@ -0,0 +1,86 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2023 ARM Limited
+ *
+ * Verify that the TPIDR2 register context in signal frames is restored.
+ */
+
+#include <signal.h>
+#include <ucontext.h>
+#include <sys/auxv.h>
+#include <sys/prctl.h>
+#include <unistd.h>
+#include <asm/sigcontext.h>
+
+#include "test_signals_utils.h"
+#include "testcases.h"
+
+#define SYS_TPIDR2 "S3_3_C13_C0_5"
+
+static uint64_t get_tpidr2(void)
+{
+	uint64_t val;
+
+	asm volatile (
+		"mrs	%0, " SYS_TPIDR2 "\n"
+		: "=r"(val)
+		:
+		: "cc");
+
+	return val;
+}
+
+static void set_tpidr2(uint64_t val)
+{
+	asm volatile (
+		"msr	" SYS_TPIDR2 ", %0\n"
+		:
+		: "r"(val)
+		: "cc");
+}
+
+
+static uint64_t initial_tpidr2;
+
+static bool save_tpidr2(struct tdescr *td)
+{
+	initial_tpidr2 = get_tpidr2();
+	fprintf(stderr, "Initial TPIDR2: %lx\n", initial_tpidr2);
+
+	return true;
+}
+
+static int modify_tpidr2(struct tdescr *td, siginfo_t *si, ucontext_t *uc)
+{
+	uint64_t my_tpidr2 = get_tpidr2();
+
+	my_tpidr2++;
+	fprintf(stderr, "Setting TPIDR2 to %lx\n", my_tpidr2);
+	set_tpidr2(my_tpidr2);
+
+	return 0;
+}
+
+static void check_tpidr2(struct tdescr *td)
+{
+	uint64_t tpidr2 = get_tpidr2();
+
+	td->pass = tpidr2 == initial_tpidr2;
+
+	if (td->pass)
+		fprintf(stderr, "TPIDR2 restored\n");
+	else
+		fprintf(stderr, "TPIDR2 was %lx but is now %lx\n",
+			initial_tpidr2, tpidr2);
+}
+
+struct tdescr tde = {
+	.name = "TPIDR2 restore",
+	.descr = "Validate that TPIDR2 is restored from the sigframe",
+	.feats_required = FEAT_SME,
+	.timeout = 3,
+	.sig_trig = SIGUSR1,
+	.init = save_tpidr2,
+	.run = modify_tpidr2,
+	.check_result = check_tpidr2,
+};