kselftest/arm64: Fix .pushsection for strings in FP tests

The .pushsection directive used to store the strings used with the .puts
macro in the floating point helpers does not provide a section type but
according to the gas documentation this should be mandatory and with the
clang built in as it actually is. Provide one so that we can build these
tests with LLVM=1.

No functional change.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Link: https://lore.kernel.org/r/20230111-arm64-kselftest-clang-v1-1-89c69d377727@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

selftests: arm64: Factor out utility functions for assembly FP tests

The various floating point test programs written in assembly have a bunch
of helper functions and macros which are cut'n'pasted between them. Factor
them out into a separate source file which is linked into all of them.

We don't include memcmp() since it isn't as generic as it should be and
directly branches to report an error in the programs.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20211019181851.3341232-1-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>

selftests: arm64: Add stress tests for FPSMID and SVE context switching

Add programs sve-test and fpsimd-test which spin reading and writing to
the SVE and FPSIMD registers, verifying the operations they perform. The
intended use is to leave them running to stress the context switch code's
handling of these registers which isn't compatible with what kselftest
does so they're not integrated into the framework but there's no other
obvious testsuite where they fit so let's store them here.

These tests were written by Dave Martin and lightly adapted by me.

Signed-off-by: Mark Brown <broonie@kernel.org>
Acked-by: Dave Martin <Dave.Martin@arm.com>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/r/20200819114837.51466-4-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>