lkml.org 
[lkml]   [2022]   [Oct]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    From
    SubjectRe: [PATCH 1/2] riscv: fix detection of toolchain Zicbom support
    Date
    Hi Conor,

    Am Donnerstag, 6. Oktober 2022, 19:35:20 CEST schrieb Conor Dooley:
    > From: Conor Dooley <conor.dooley@microchip.com>
    >
    > 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@baylibre.com>
    > 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@microchip.com>
    > ---
    > 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 d557cc50295d..6da36553158b 100644
    > --- a/arch/riscv/Kconfig
    > +++ b/arch/riscv/Kconfig
    > @@ -401,14 +401,16 @@ 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 >= 23900

    I did needed to look quite closely at the cc-option-voodoo, but it really
    seems to work out as expected :-)

    I can't say much to the specific L(L)D_VERSION values but the change itself
    looks good, so

    Reviewed-by: Heiko Stuebner <heiko@sntech.de>

    >
    > 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 3fa8ef336822..3607d38edb4f 100644
    > --- a/arch/riscv/Makefile
    > +++ b/arch/riscv/Makefile
    > @@ -57,8 +57,7 @@ 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)
    >




    \
     
     \ /
      Last update: 2022-10-06 19:54    [W:3.263 / U:1.204 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site