On Thu, Dec 28, 2023 at 5:11 AM Samuel Holland <samuel.holland@xxxxxxxxxx> wrote: > > This series unifies the kernel-mode FPU API across several architectures > by wrapping the existing functions (where needed) in consistently-named > functions placed in a consistent header location, with mostly the same > semantics: they can be called from preemptible or non-preemptible task > context, and are not assumed to be reentrant. Architectures are also > expected to provide CFLAGS adjustments for compiling FPU-dependent code. > For the moment, SIMD/vector units are out of scope for this common API. > > This allows us to remove the ifdeffery and duplicated Makefile logic at > each FPU user. It then implements the common API on RISC-V, and converts > a couple of users to the new API: the AMDGPU DRM driver, and the FPU > self test. > > The underlying goal of this series is to allow using newer AMD GPUs > (e.g. Navi) on RISC-V boards such as SiFive's HiFive Unmatched. Those > GPUs need CONFIG_DRM_AMD_DC_FP to initialize, which requires kernel-mode > FPU support. Series is: Acked-by: Alex Deucher <alexander.deucher@xxxxxxx> > > Previous versions: > v1: https://lore.kernel.org/linux-kernel/20231208055501.2916202-1-samuel.holland@xxxxxxxxxx/ > v0: https://lore.kernel.org/linux-kernel/20231122030621.3759313-1-samuel.holland@xxxxxxxxxx/ > > Changes in v2: > - Add documentation explaining the built-time and runtime APIs > - Add a linux/fpu.h header for generic isolation enforcement > - Remove file name from header comment > - Clean up arch/arm64/lib/Makefile, like for arch/arm > - Remove RISC-V architecture-specific preprocessor check > - Split altivec removal to a separate patch > - Use linux/fpu.h instead of asm/fpu.h in consumers > - Declare test_fpu() in a header > > Michael Ellerman (1): > drm/amd/display: Only use hard-float, not altivec on powerpc > > Samuel Holland (13): > arch: Add ARCH_HAS_KERNEL_FPU_SUPPORT > ARM: Implement ARCH_HAS_KERNEL_FPU_SUPPORT > ARM: crypto: Use CC_FLAGS_FPU for NEON CFLAGS > arm64: Implement ARCH_HAS_KERNEL_FPU_SUPPORT > arm64: crypto: Use CC_FLAGS_FPU for NEON CFLAGS > lib/raid6: Use CC_FLAGS_FPU for NEON CFLAGS > LoongArch: Implement ARCH_HAS_KERNEL_FPU_SUPPORT > powerpc: Implement ARCH_HAS_KERNEL_FPU_SUPPORT > x86: Implement ARCH_HAS_KERNEL_FPU_SUPPORT > riscv: Add support for kernel-mode FPU > drm/amd/display: Use ARCH_HAS_KERNEL_FPU_SUPPORT > selftests/fpu: Move FP code to a separate translation unit > selftests/fpu: Allow building on other architectures > > Documentation/core-api/floating-point.rst | 78 +++++++++++++++++++ > Documentation/core-api/index.rst | 1 + > Makefile | 5 ++ > arch/Kconfig | 6 ++ > arch/arm/Kconfig | 1 + > arch/arm/Makefile | 7 ++ > arch/arm/include/asm/fpu.h | 15 ++++ > arch/arm/lib/Makefile | 3 +- > arch/arm64/Kconfig | 1 + > arch/arm64/Makefile | 9 ++- > arch/arm64/include/asm/fpu.h | 15 ++++ > arch/arm64/lib/Makefile | 6 +- > arch/loongarch/Kconfig | 1 + > arch/loongarch/Makefile | 5 +- > arch/loongarch/include/asm/fpu.h | 1 + > arch/powerpc/Kconfig | 1 + > arch/powerpc/Makefile | 5 +- > arch/powerpc/include/asm/fpu.h | 28 +++++++ > arch/riscv/Kconfig | 1 + > arch/riscv/Makefile | 3 + > arch/riscv/include/asm/fpu.h | 16 ++++ > arch/riscv/kernel/Makefile | 1 + > arch/riscv/kernel/kernel_mode_fpu.c | 28 +++++++ > arch/x86/Kconfig | 1 + > arch/x86/Makefile | 20 +++++ > arch/x86/include/asm/fpu.h | 13 ++++ > drivers/gpu/drm/amd/display/Kconfig | 2 +- > .../gpu/drm/amd/display/amdgpu_dm/dc_fpu.c | 35 +-------- > drivers/gpu/drm/amd/display/dc/dml/Makefile | 36 +-------- > drivers/gpu/drm/amd/display/dc/dml2/Makefile | 36 +-------- > include/linux/fpu.h | 12 +++ > lib/Kconfig.debug | 2 +- > lib/Makefile | 26 +------ > lib/raid6/Makefile | 31 ++------ > lib/test_fpu.h | 8 ++ > lib/{test_fpu.c => test_fpu_glue.c} | 37 ++------- > lib/test_fpu_impl.c | 37 +++++++++ > 37 files changed, 343 insertions(+), 190 deletions(-) > create mode 100644 Documentation/core-api/floating-point.rst > create mode 100644 arch/arm/include/asm/fpu.h > create mode 100644 arch/arm64/include/asm/fpu.h > create mode 100644 arch/powerpc/include/asm/fpu.h > create mode 100644 arch/riscv/include/asm/fpu.h > create mode 100644 arch/riscv/kernel/kernel_mode_fpu.c > create mode 100644 arch/x86/include/asm/fpu.h > create mode 100644 include/linux/fpu.h > create mode 100644 lib/test_fpu.h > rename lib/{test_fpu.c => test_fpu_glue.c} (71%) > create mode 100644 lib/test_fpu_impl.c > > -- > 2.42.0 >
