On Thu, Jan 4, 2024 at 11:58 PM Samuel Holland <samuel.holland@xxxxxxxxxx> wrote: > > Hi Huacai, > > On 2024-01-04 3:55 AM, Huacai Chen wrote: > > Hi, Samuel, > > > > On Thu, Dec 28, 2023 at 9:42 AM Samuel Holland > > <samuel.holland@xxxxxxxxxx> wrote: > >> > >> LoongArch already provides kernel_fpu_begin() and kernel_fpu_end() in > >> asm/fpu.h, so it only needs to add kernel_fpu_available() and export > >> the CFLAGS adjustments. > >> > >> Acked-by: WANG Xuerui <git@xxxxxxxxxx> > >> Reviewed-by: Christoph Hellwig <hch@xxxxxx> > >> Signed-off-by: Samuel Holland <samuel.holland@xxxxxxxxxx> > >> --- > >> > >> (no changes since v1) > >> > >> arch/loongarch/Kconfig | 1 + > >> arch/loongarch/Makefile | 5 ++++- > >> arch/loongarch/include/asm/fpu.h | 1 + > >> 3 files changed, 6 insertions(+), 1 deletion(-) > >> > >> diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig > >> index ee123820a476..65d4475565b8 100644 > >> --- a/arch/loongarch/Kconfig > >> +++ b/arch/loongarch/Kconfig > >> @@ -15,6 +15,7 @@ config LOONGARCH > >> select ARCH_HAS_CPU_FINALIZE_INIT > >> select ARCH_HAS_FORTIFY_SOURCE > >> select ARCH_HAS_KCOV > >> + select ARCH_HAS_KERNEL_FPU_SUPPORT if CPU_HAS_FPU > >> select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS > >> select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE > >> select ARCH_HAS_PTE_SPECIAL > >> diff --git a/arch/loongarch/Makefile b/arch/loongarch/Makefile > >> index 4ba8d67ddb09..1afe28feaba5 100644 > >> --- a/arch/loongarch/Makefile > >> +++ b/arch/loongarch/Makefile > >> @@ -25,6 +25,9 @@ endif > >> 32bit-emul = elf32loongarch > >> 64bit-emul = elf64loongarch > >> > >> +CC_FLAGS_FPU := -mfpu=64 > >> +CC_FLAGS_NO_FPU := -msoft-float > > We will add LoongArch32 support later, maybe it should be -mfpu=32 in > > that case, and do other archs have the case that only support FP32? > > Do you mean that LoongArch32 does not support double-precision FP in hardware? > At least both of the consumers in this series use double-precision, so my first > thought is that LoongArch32 could not select ARCH_HAS_KERNEL_FPU_SUPPORT. Then is it possible to introduce CC_FLAGS_SP_FPU and CC_FLAGS_DP_FPU? I think there may be some place where SP FP is enough. Huacai > > Regards, > Samuel >