[PATCH v3 08/28] arm64/sve: Kconfig update and conditional compilation support
From: Dave.Martin@arm.com (Dave Martin)
Date: 2017-10-10 18:38:25
Also in:
kvmarm, linux-arch
Subsystem:
arm64 port (aarch64 architecture), the rest · Maintainers:
Catalin Marinas, Will Deacon, Linus Torvalds
This patch adds CONFIG_ARM64_SVE to control building of SVE support into the kernel, and adds a stub predicate system_supports_sve() to control conditional compilation and runtime SVE support. system_supports_sve() just returns false for now: it will be replaced with a non-trivial implementation in a later patch, once SVE support is complete enough to be enabled safely. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Alex Benn?e <redacted> --- arch/arm64/Kconfig | 11 +++++++++++ arch/arm64/include/asm/cpufeature.h | 5 +++++ 2 files changed, 16 insertions(+)
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index ca711ac..9b3a50e 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig@@ -975,6 +975,17 @@ config ARM64_PMEM endmenu +config ARM64_SVE + bool "ARM Scalable Vector Extension support" + default y + help + The Scalable Vector Extension (SVE) is an extension to the AArch64 + execution state which complements and extends the SIMD functionality + of the base architecture to support much larger vectors and to enable + additional vectorisation opportunities. + + To enable use of this extension on CPUs that implement it, say Y. + config ARM64_MODULE_CMODEL_LARGE bool
diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h
index 428ee1f..4ea3441 100644
--- a/arch/arm64/include/asm/cpufeature.h
+++ b/arch/arm64/include/asm/cpufeature.h@@ -262,6 +262,11 @@ static inline bool system_uses_ttbr0_pan(void) !cpus_have_const_cap(ARM64_HAS_PAN); } +static inline bool system_supports_sve(void) +{ + return false; +} + #endif /* __ASSEMBLY__ */ #endif
--
2.1.4