From b11b998e983119e27b33210a0128b27df6ae5f78 Mon Sep 17 00:00:00 2001 From: Samuel Holland Date: Fri, 29 Mar 2024 00:18:24 -0700 Subject: x86/fpu: fix asm/fpu/types.h include guard MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Patch series "Unified cross-architecture kernel-mode FPU API", v4. 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. This patch (of 15): The include guard should match the filename, or it will conflict with the newly-added asm/fpu.h. Link: https://lkml.kernel.org/r/20240329072441.591471-1-samuel.holland@sifive.com Link: https://lkml.kernel.org/r/20240329072441.591471-10-samuel.holland@sifive.com Signed-off-by: Samuel Holland Acked-by: Dave Hansen Acked-by: Christian König Cc: Borislav Petkov (AMD) Cc: Catalin Marinas Cc: Christoph Hellwig Cc: Huacai Chen Cc: Ingo Molnar Cc: Jonathan Corbet Cc: Masahiro Yamada Cc: Nathan Chancellor Cc: Nicolas Schier Cc: Russell King Cc: Thomas Gleixner Cc: Will Deacon Cc: Alex Deucher Cc: Michael Ellerman Cc: Palmer Dabbelt Cc: WANG Xuerui Signed-off-by: Andrew Morton --- arch/x86/include/asm/fpu/types.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'arch/x86') diff --git a/arch/x86/include/asm/fpu/types.h b/arch/x86/include/asm/fpu/types.h index ace9aa3b78a3..eb17f31b06d2 100644 --- a/arch/x86/include/asm/fpu/types.h +++ b/arch/x86/include/asm/fpu/types.h @@ -2,8 +2,8 @@ /* * FPU data structures: */ -#ifndef _ASM_X86_FPU_H -#define _ASM_X86_FPU_H +#ifndef _ASM_X86_FPU_TYPES_H +#define _ASM_X86_FPU_TYPES_H #include @@ -596,4 +596,4 @@ struct fpu_state_config { /* FPU state configuration information */ extern struct fpu_state_config fpu_kernel_cfg, fpu_user_cfg; -#endif /* _ASM_X86_FPU_H */ +#endif /* _ASM_X86_FPU_TYPES_H */ -- cgit v1.2.3 From b0b8a15bb89e09e12aa6be8ae28128bb656338f1 Mon Sep 17 00:00:00 2001 From: Samuel Holland Date: Fri, 29 Mar 2024 00:18:25 -0700 Subject: x86: implement ARCH_HAS_KERNEL_FPU_SUPPORT MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit x86 already provides kernel_fpu_begin() and kernel_fpu_end(), but in a different header. Add a wrapper header, and export the CFLAGS adjustments as found in lib/Makefile. Link: https://lkml.kernel.org/r/20240329072441.591471-11-samuel.holland@sifive.com Signed-off-by: Samuel Holland Reviewed-by: Christoph Hellwig Acked-by: Christian König Cc: Alex Deucher Cc: Borislav Petkov (AMD) Cc: Catalin Marinas Cc: Dave Hansen Cc: Huacai Chen Cc: Ingo Molnar Cc: Jonathan Corbet Cc: Masahiro Yamada Cc: Michael Ellerman Cc: Nathan Chancellor Cc: Nicolas Schier Cc: Palmer Dabbelt Cc: Russell King Cc: Thomas Gleixner Cc: WANG Xuerui Cc: Will Deacon Signed-off-by: Andrew Morton --- arch/x86/Kconfig | 1 + arch/x86/Makefile | 20 ++++++++++++++++++++ arch/x86/include/asm/fpu.h | 13 +++++++++++++ 3 files changed, 34 insertions(+) create mode 100644 arch/x86/include/asm/fpu.h (limited to 'arch/x86') diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 671bc6fd557c..1d7122a1883e 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -85,6 +85,7 @@ config X86 select ARCH_HAS_FORTIFY_SOURCE select ARCH_HAS_GCOV_PROFILE_ALL select ARCH_HAS_KCOV if X86_64 + select ARCH_HAS_KERNEL_FPU_SUPPORT select ARCH_HAS_MEM_ENCRYPT select ARCH_HAS_MEMBARRIER_SYNC_CORE select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS diff --git a/arch/x86/Makefile b/arch/x86/Makefile index 5ab93fcdd691..164498b3382a 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -74,6 +74,26 @@ KBUILD_CFLAGS += -mno-sse -mno-mmx -mno-sse2 -mno-3dnow -mno-avx KBUILD_RUSTFLAGS += --target=$(objtree)/scripts/target.json KBUILD_RUSTFLAGS += -Ctarget-feature=-sse,-sse2,-sse3,-ssse3,-sse4.1,-sse4.2,-avx,-avx2 +# +# CFLAGS for compiling floating point code inside the kernel. +# +CC_FLAGS_FPU := -msse -msse2 +ifdef CONFIG_CC_IS_GCC +# Stack alignment mismatch, proceed with caution. +# GCC < 7.1 cannot compile code using `double` and -mpreferred-stack-boundary=3 +# (8B stack alignment). +# See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=53383 +# +# The "-msse" in the first argument is there so that the +# -mpreferred-stack-boundary=3 build error: +# +# -mpreferred-stack-boundary=3 is not between 4 and 12 +# +# can be triggered. Otherwise gcc doesn't complain. +CC_FLAGS_FPU += -mhard-float +CC_FLAGS_FPU += $(call cc-option,-msse -mpreferred-stack-boundary=3,-mpreferred-stack-boundary=4) +endif + ifeq ($(CONFIG_X86_KERNEL_IBT),y) # # Kernel IBT has S_CET.NOTRACK_EN=0, as such the compilers must not generate diff --git a/arch/x86/include/asm/fpu.h b/arch/x86/include/asm/fpu.h new file mode 100644 index 000000000000..b2743fe19339 --- /dev/null +++ b/arch/x86/include/asm/fpu.h @@ -0,0 +1,13 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2023 SiFive + */ + +#ifndef _ASM_X86_FPU_H +#define _ASM_X86_FPU_H + +#include + +#define kernel_fpu_available() true + +#endif /* ! _ASM_X86_FPU_H */ -- cgit v1.2.3