kselftest/arm64: Extend vector configuration API tests to cover SME

Provide RDVL helpers for SME and extend the main vector configuration tests
to cover SME.

Signed-off-by: Mark Brown <[e-mail]>
Reviewed-by: Shuah Khan <[e-mail]>
Acked-by: Catalin Marinas <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Catalin Marinas <[e-mail]>

tools/testing/selftests/arm64/fp/.gitignore

···
 fp-pidbench
 fpsimd-test
+rdvl-sme
 rdvl-sve
 sve-probe-vls
 sve-ptrace

tools/testing/selftests/arm64/fp/Makefile

···
 CFLAGS += -I../../../../../usr/include/
 TEST_GEN_PROGS := sve-ptrace sve-probe-vls vec-syscfg
 TEST_PROGS_EXTENDED := fp-pidbench fpsimd-test fpsimd-stress \
-	rdvl-sve \
+	rdvl-sme rdvl-sve \
 	sve-test sve-stress \
 	vlset
 
···
 	$(CC) -nostdlib $^ -o $@
 fpsimd-test: fpsimd-test.o asm-utils.o
 	$(CC) -nostdlib $^ -o $@
+rdvl-sme: rdvl-sme.o rdvl.o
 rdvl-sve: rdvl-sve.o rdvl.o
 sve-ptrace: sve-ptrace.o
 sve-probe-vls: sve-probe-vls.o rdvl.o

tools/testing/selftests/arm64/fp/rdvl-sme.c

···
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <stdio.h>
+
+#include "rdvl.h"
+
+int main(void)
+{
+	int vl = rdvl_sme();
+
+	printf("%d\n", vl);
+
+	return 0;
+}

tools/testing/selftests/arm64/fp/rdvl.S

···
 // SPDX-License-Identifier: GPL-2.0-only
 // Copyright (C) 2021 ARM Limited.
 
+#include "sme-inst.h"
+
 .arch_extension sve
 
 .globl rdvl_sve
 rdvl_sve:
 	hint	34			// BTI C
 	rdvl	x0, #1
+	ret
+
+.globl rdvl_sme
+rdvl_sme:
+	hint	34			// BTI C
+
+	rdsvl	0, 1
+
 	ret

tools/testing/selftests/arm64/fp/rdvl.h

···
 #ifndef RDVL_H
 #define RDVL_H
 
+int rdvl_sme(void);
 int rdvl_sve(void);
 
 #endif

tools/testing/selftests/arm64/fp/vec-syscfg.c

···
 		.prctl_set = PR_SVE_SET_VL,
 		.default_vl_file = "/proc/sys/abi/sve_default_vector_length",
 	},
+	{
+		.name = "SME",
+		.hwcap_type = AT_HWCAP2,
+		.hwcap = HWCAP2_SME,
+		.rdvl = rdvl_sme,
+		.rdvl_binary = "./rdvl-sme",
+		.prctl_get = PR_SME_GET_VL,
+		.prctl_set = PR_SME_SET_VL,
+		.default_vl_file = "/proc/sys/abi/sme_default_vector_length",
+	},
 };
 
 static int stdio_read_integer(FILE *f, const char *what, int *val)