1 files changed, 58 insertions, 0 deletions
diff --git a/tools/testing/selftests/arm64/fp/sve-probe-vls.c b/tools/testing/selftests/arm64/fp/sve-probe-vls.c
new file mode 100644
index 000000000000..b29cbc642c57
--- /dev/null
+++ b/tools/testing/selftests/arm64/fp/sve-probe-vls.c
@@ -0,0 +1,58 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2015-2020 ARM Limited.
+ * Original author: Dave Martin <Dave.Martin@arm.com>
+ */
+#include <assert.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/auxv.h>
+#include <sys/prctl.h>
+#include <asm/sigcontext.h>
+
+#include "../../kselftest.h"
+
+int main(int argc, char **argv)
+{
+	unsigned int vq;
+	int vl;
+	static unsigned int vqs[SVE_VQ_MAX];
+	unsigned int nvqs = 0;
+
+	ksft_print_header();
+	ksft_set_plan(2);
+
+	if (!(getauxval(AT_HWCAP) & HWCAP_SVE))
+		ksft_exit_skip("SVE not available");
+
+	/*
+	 * Enumerate up to SVE_VQ_MAX vector lengths
+	 */
+	for (vq = SVE_VQ_MAX; vq > 0; --vq) {
+		vl = prctl(PR_SVE_SET_VL, vq * 16);
+		if (vl == -1)
+			ksft_exit_fail_msg("PR_SVE_SET_VL failed: %s (%d)\n",
+					   strerror(errno), errno);
+
+		vl &= PR_SVE_VL_LEN_MASK;
+
+		if (!sve_vl_valid(vl))
+			ksft_exit_fail_msg("VL %d invalid\n", vl);
+		vq = sve_vq_from_vl(vl);
+
+		if (!(nvqs < SVE_VQ_MAX))
+			ksft_exit_fail_msg("Too many VLs %u >= SVE_VQ_MAX\n",
+					   nvqs);
+		vqs[nvqs++] = vq;
+	}
+	ksft_test_result_pass("Enumerated %d vector lengths\n", nvqs);
+	ksft_test_result_pass("All vector lengths valid\n");
+
+	/* Print out the vector lengths in ascending order: */
+	while (nvqs--)
+		ksft_print_msg("%u\n", 16 * vqs[nvqs]);
+
+	ksft_exit_pass();
+}