Commit 77108610 authored by Mark Brown's avatar Mark Brown Committed by Catalin Marinas
Browse files

kselftest/arm64: Provide a helper binary and "library" for SVE RDVL 



SVE provides an instruction RDVL which reports the currently configured
vector length. In order to validate that our vector length configuration
interfaces are working correctly without having to build the C code for
our test programs with SVE enabled provide a trivial assembly library
with a C callable function that executes RDVL. Since these interfaces
also control behaviour on exec*() provide a trivial wrapper program which
reports the currently configured vector length on stdout, tests can use
this to verify that behaviour on exec*() is as expected.

In preparation for providing similar helper functionality for SME, the
Scalable Matrix Extension, which allows separately configured vector
lengths to be read back both the assembler function and wrapper binary
have SVE included in their name.

Signed-off-by: default avatarMark Brown <broonie@kernel.org>
Reviewed-by: default avatarDave Martin <Dave.Martin@arm.com>
Link: https://lore.kernel.org/r/20210803140450.46624-2-broonie@kernel.org


Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
parent dac3ce63

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

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fpsimd-test

rdvl-sve

sve-probe-vls

sve-ptrace

sve-test

tools/testing/selftests/arm64/fp/Makefile

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@@ -2,12 +2,16 @@ 


CFLAGS += -I../../../../../usr/include/

TEST_GEN_PROGS := sve-ptrace sve-probe-vls

TEST_PROGS_EXTENDED := fpsimd-test fpsimd-stress sve-test sve-stress vlset

TEST_PROGS_EXTENDED := fpsimd-test fpsimd-stress \

	rdvl-sve \

	sve-test sve-stress \

	vlset



all: $(TEST_GEN_PROGS) $(TEST_PROGS_EXTENDED)



fpsimd-test: fpsimd-test.o

	$(CC) -nostdlib $^ -o $@

rdvl-sve: rdvl-sve.o rdvl.o

sve-ptrace: sve-ptrace.o sve-ptrace-asm.o

sve-probe-vls: sve-probe-vls.o

sve-test: sve-test.o

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

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// SPDX-License-Identifier: GPL-2.0-only



#include <stdio.h>



#include "rdvl.h"



int main(void)

{

	int vl = rdvl_sve();



	printf("%d\n", vl);



	return 0;

}

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

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// SPDX-License-Identifier: GPL-2.0-only

// Copyright (C) 2021 ARM Limited.



.arch_extension sve



.globl rdvl_sve

rdvl_sve:

	hint	34			// BTI C

	rdvl	x0, #1

	ret

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

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/* SPDX-License-Identifier: GPL-2.0-only */



#ifndef RDVL_H

#define RDVL_H



int rdvl_sve(void);



#endif