The quilt patch titled
Subject: powerpc: implement ARCH_HAS_KERNEL_FPU_SUPPORT
has been removed from the -mm tree. Its filename was
powerpc-implement-arch_has_kernel_fpu_support.patch
This patch was dropped because it was merged into the mm-nonmm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: Samuel Holland <samuel.holland@xxxxxxxxxx>
Subject: powerpc: implement ARCH_HAS_KERNEL_FPU_SUPPORT
Date: Fri, 29 Mar 2024 00:18:23 -0700
PowerPC provides an equivalent to the common kernel-mode FPU API, but in a
different header and using different function names. The PowerPC API also
requires a non-preemptible context. Add a wrapper header, and export the
CFLAGS adjustments.
Link: https://lkml.kernel.org/r/20240329072441.591471-9-samuel.holland@xxxxxxxxxx
Signed-off-by: Samuel Holland <samuel.holland@xxxxxxxxxx>
Acked-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> (powerpc)
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Acked-by: Christian König <christian.koenig@xxxxxxx>
Cc: Alex Deucher <alexander.deucher@xxxxxxx>
Cc: Borislav Petkov (AMD) <bp@xxxxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: Huacai Chen <chenhuacai@xxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Jonathan Corbet <corbet@xxxxxxx>
Cc: Masahiro Yamada <masahiroy@xxxxxxxxxx>
Cc: Nathan Chancellor <nathan@xxxxxxxxxx>
Cc: Nicolas Schier <nicolas@xxxxxxxxx>
Cc: Palmer Dabbelt <palmer@xxxxxxxxxxxx>
Cc: Russell King <linux@xxxxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: WANG Xuerui <git@xxxxxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
arch/powerpc/Kconfig | 1 +
arch/powerpc/Makefile | 5 ++++-
arch/powerpc/include/asm/fpu.h | 28 ++++++++++++++++++++++++++++
3 files changed, 33 insertions(+), 1 deletion(-)
--- /dev/null
+++ a/arch/powerpc/include/asm/fpu.h
@@ -0,0 +1,28 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2023 SiFive
+ */
+
+#ifndef _ASM_POWERPC_FPU_H
+#define _ASM_POWERPC_FPU_H
+
+#include <linux/preempt.h>
+
+#include <asm/cpu_has_feature.h>
+#include <asm/switch_to.h>
+
+#define kernel_fpu_available() (!cpu_has_feature(CPU_FTR_FPU_UNAVAILABLE))
+
+static inline void kernel_fpu_begin(void)
+{
+ preempt_disable();
+ enable_kernel_fp();
+}
+
+static inline void kernel_fpu_end(void)
+{
+ disable_kernel_fp();
+ preempt_enable();
+}
+
+#endif /* ! _ASM_POWERPC_FPU_H */
--- a/arch/powerpc/Kconfig~powerpc-implement-arch_has_kernel_fpu_support
+++ a/arch/powerpc/Kconfig
@@ -137,6 +137,7 @@ config PPC
select ARCH_HAS_GCOV_PROFILE_ALL
select ARCH_HAS_HUGEPD if HUGETLB_PAGE
select ARCH_HAS_KCOV
+ select ARCH_HAS_KERNEL_FPU_SUPPORT if PPC_FPU
select ARCH_HAS_MEMBARRIER_CALLBACKS
select ARCH_HAS_MEMBARRIER_SYNC_CORE
select ARCH_HAS_MEMREMAP_COMPAT_ALIGN if PPC_64S_HASH_MMU
--- a/arch/powerpc/Makefile~powerpc-implement-arch_has_kernel_fpu_support
+++ a/arch/powerpc/Makefile
@@ -149,6 +149,9 @@ CFLAGS-$(CONFIG_PPC32) += $(call cc-opti
CFLAGS-$(CONFIG_PPC32) += $(call cc-option,-mno-readonly-in-sdata)
+CC_FLAGS_FPU := $(call cc-option,-mhard-float)
+CC_FLAGS_NO_FPU := $(call cc-option,-msoft-float)
+
ifdef CONFIG_FUNCTION_TRACER
ifdef CONFIG_ARCH_USING_PATCHABLE_FUNCTION_ENTRY
KBUILD_CPPFLAGS += -DCC_USING_PATCHABLE_FUNCTION_ENTRY
@@ -170,7 +173,7 @@ asinstr := $(call as-instr,lis 9$(comma)
KBUILD_CPPFLAGS += -I $(srctree)/arch/powerpc $(asinstr)
KBUILD_AFLAGS += $(AFLAGS-y)
-KBUILD_CFLAGS += $(call cc-option,-msoft-float)
+KBUILD_CFLAGS += $(CC_FLAGS_NO_FPU)
KBUILD_CFLAGS += $(CFLAGS-y)
CPP = $(CC) -E $(KBUILD_CFLAGS)
_
Patches currently in -mm which might be from samuel.holland@xxxxxxxxxx are
