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| author | Ard Biesheuvel <ard.biesheuvel@linaro.org> | 2014-07-04 19:41:53 +0200 |
|---|---|---|
| committer | Matt Fleming <matt.fleming@intel.com> | 2014-07-07 20:29:42 +0100 |
| commit | e15dd4949a937d8e8482f37f8fe493357417f203 (patch) | |
| tree | d66dba79a540033a0072d7ebfcfa1667783227f2 /arch/arm64/Kconfig | |
| parent | 022ee6c558fc933679e151f00f84332974147fa2 (diff) | |
| download | lwn-e15dd4949a937d8e8482f37f8fe493357417f203.tar.gz lwn-e15dd4949a937d8e8482f37f8fe493357417f203.zip | |
efi/arm64: Preserve FP/SIMD registers on UEFI runtime services calls
According to the UEFI spec section 2.3.6.4, the use of FP/SIMD
instructions is allowed, and should adhere to the AAPCS64 calling
convention, which states that 'only the bottom 64 bits of each value
stored in registers v8-v15 need to be preserved' (section 5.1.2).
This applies equally to UEFI Runtime Services called by the kernel, so
make sure the FP/SIMD register file is preserved in this case. We do this
by enabling the wrappers for UEFI Runtime Services (CONFIG_EFI_RUNTIME_WRAPPERS)
and inserting calls to kernel_neon_begin()and kernel_neon_end() into
these wrappers.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Diffstat (limited to 'arch/arm64/Kconfig')
| -rw-r--r-- | arch/arm64/Kconfig | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 7295419165e1..2cc14cef01bd 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -298,6 +298,7 @@ config EFI select LIBFDT select UCS2_STRING select EFI_PARAMS_FROM_FDT + select EFI_RUNTIME_WRAPPERS default y help This option provides support for runtime services provided |