From: Conor Dooley <conor.dooley@xxxxxxxxxxxxx> [ Upstream commit b8c86872d1dc171d8f1c137917d6913cae2fa4f2 ] 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 Zicbom but GNU bintutils 2.35.2 does not, leading build errors like so: riscv64-linux-gnu-ld: -march=rv64i2p0_m2p0_a2p0_c2p0_zicbom1p0_zihintpause2p0: Invalid or unknown z ISA extension: 'zicbom' Convert CC_HAS_ZICBOM to TOOLCHAIN_HAS_ZICBOM & check if the linker also supports Zicbom. Reported-by: Kevin Hilman <khilman@xxxxxxxxxxxx> Link: https://github.com/ClangBuiltLinux/linux/issues/1714 Link: https://storage.kernelci.org/next/master/next-20220920/riscv/defconfig+CONFIG_EFI=n/clang-16/logs/kernel.log Fixes: 1631ba1259d6 ("riscv: Add support for non-coherent devices using zicbom extension") Signed-off-by: Conor Dooley <conor.dooley@xxxxxxxxxxxxx> Reviewed-by: Heiko Stuebner <heiko@xxxxxxxxx> Reviewed-by: Nathan Chancellor <nathan@xxxxxxxxxx> Link: https://lore.kernel.org/r/20221006173520.1785507-2-conor@xxxxxxxxxx [Palmer: Check for ld-2.38, not 2.39, as 2.38 no longer errors.] Signed-off-by: Palmer Dabbelt <palmer@xxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- arch/riscv/Kconfig | 10 ++++++---- arch/riscv/Makefile | 3 +-- 2 files changed, 7 insertions(+), 6 deletions(-) diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index cea22ccb57cb..e646298d2d65 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -402,14 +402,16 @@ config RISCV_ISA_SVPBMT If you don't know what to do here, say Y. -config CC_HAS_ZICBOM +config TOOLCHAIN_HAS_ZICBOM bool - default y if 64BIT && $(cc-option,-mabi=lp64 -march=rv64ima_zicbom) - default y if 32BIT && $(cc-option,-mabi=ilp32 -march=rv32ima_zicbom) + default y + depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zicbom) + depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zicbom) + depends on LLD_VERSION >= 150000 || LD_VERSION >= 23800 config RISCV_ISA_ZICBOM bool "Zicbom extension support for non-coherent DMA operation" - depends on CC_HAS_ZICBOM + depends on TOOLCHAIN_HAS_ZICBOM depends on !XIP_KERNEL && MMU select RISCV_DMA_NONCOHERENT select RISCV_ALTERNATIVE diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile index e7d52a2301e2..d1dbbe0fb0f8 100644 --- a/arch/riscv/Makefile +++ b/arch/riscv/Makefile @@ -59,8 +59,7 @@ toolchain-need-zicsr-zifencei := $(call cc-option-yn, -march=$(riscv-march-y)_zi riscv-march-$(toolchain-need-zicsr-zifencei) := $(riscv-march-y)_zicsr_zifencei # Check if the toolchain supports Zicbom extension -toolchain-supports-zicbom := $(call cc-option-yn, -march=$(riscv-march-y)_zicbom) -riscv-march-$(toolchain-supports-zicbom) := $(riscv-march-y)_zicbom +riscv-march-$(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) -- 2.35.1
