summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorConor Dooley <conor.dooley@microchip.com>2022-10-06 18:35:21 +0100
committerPalmer Dabbelt <palmer@rivosinc.com>2022-10-27 15:13:06 -0700
commitaae538cd03bc8fc35979653d9180922d146da0ca (patch)
tree93c3b45399e77552e941e87c1c21ad5bddcddb40
parentb8c86872d1dc171d8f1c137917d6913cae2fa4f2 (diff)
downloadlinux-aae538cd03bc8fc35979653d9180922d146da0ca.tar.bz2
riscv: fix detection of toolchain Zihintpause support
It is not sufficient to check if a toolchain supports a particular extension without checking if the linker supports that extension too. For example, Clang 15 supports Zihintpause but GNU bintutils 2.35.2 does not, leading build errors like so: riscv64-linux-gnu-ld: -march=rv64i2p0_m2p0_a2p0_c2p0_zihintpause2p0: Invalid or unknown z ISA extension: 'zihintpause' Add a TOOLCHAIN_HAS_ZIHINTPAUSE which checks if each of the compiler, assembler and linker support the extension. Replace the ifdef in the vdso with one depending on this new symbol. Fixes: 8eb060e10185 ("arch/riscv: add Zihintpause support") Signed-off-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Heiko Stuebner <heiko@sntech.de> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Link: https://lore.kernel.org/r/20221006173520.1785507-3-conor@kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
-rw-r--r--arch/riscv/Kconfig7
-rw-r--r--arch/riscv/Makefile3
-rw-r--r--arch/riscv/include/asm/vdso/processor.h2
3 files changed, 9 insertions, 3 deletions
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index 4c6a09f05348..d984f61d5eab 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -425,6 +425,13 @@ config RISCV_ISA_ZICBOM
If you don't know what to do here, say Y.
+config TOOLCHAIN_HAS_ZIHINTPAUSE
+ bool
+ default y
+ depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zihintpause)
+ depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zihintpause)
+ depends on LLD_VERSION >= 150000 || LD_VERSION >= 23600
+
config FPU
bool "FPU support"
default y
diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile
index 3607d38edb4f..6651517f3962 100644
--- a/arch/riscv/Makefile
+++ b/arch/riscv/Makefile
@@ -60,8 +60,7 @@ riscv-march-$(toolchain-need-zicsr-zifencei) := $(riscv-march-y)_zicsr_zifencei
riscv-march-$(CONFIG_TOOLCHAIN_HAS_ZICBOM) := $(riscv-march-y)_zicbom
# Check if the toolchain supports Zihintpause extension
-toolchain-supports-zihintpause := $(call cc-option-yn, -march=$(riscv-march-y)_zihintpause)
-riscv-march-$(toolchain-supports-zihintpause) := $(riscv-march-y)_zihintpause
+riscv-march-$(CONFIG_TOOLCHAIN_HAS_ZIHINTPAUSE) := $(riscv-march-y)_zihintpause
KBUILD_CFLAGS += -march=$(subst fd,,$(riscv-march-y))
KBUILD_AFLAGS += -march=$(riscv-march-y)
diff --git a/arch/riscv/include/asm/vdso/processor.h b/arch/riscv/include/asm/vdso/processor.h
index 1e4f8b4aef79..fa70cfe507aa 100644
--- a/arch/riscv/include/asm/vdso/processor.h
+++ b/arch/riscv/include/asm/vdso/processor.h
@@ -21,7 +21,7 @@ static inline void cpu_relax(void)
* Reduce instruction retirement.
* This assumes the PC changes.
*/
-#ifdef __riscv_zihintpause
+#ifdef CONFIG_TOOLCHAIN_HAS_ZIHINTPAUSE
__asm__ __volatile__ ("pause");
#else
/* Encoding of the pause instruction */