On Thu, 24 Nov 2016 00:02:08 +1100 Nicholas Piggin <npig...@gmail.com> wrote:
> GCC can compile with either endian, but the ABI version always > defaults to the default endian. Alan Modra says: Okay I was missing mcall-aixdesc, thanks again to Alan for pointing it out. This updated patch seems to do better, and it builds BE kernel with powerpc64le-gcc, and LE with powerpc64-gcc here (I did see a link failure but then couldn't reproduce it so it might have been a stale file hanging around somewhere). From: Nicholas Piggin <npig...@gmail.com> Date: Wed, 23 Nov 2016 17:27:39 +1100 Subject: [PATCH] powerpc: allow compilation on cross-endian toolchain GCC can compile with either endian, but the ABI version always defaults to the default endian. Alan Modra says: you need both -mbig and -mabi=elfv1 to make a powerpc64le gcc generate powerpc64 code The opposite is true for powerpc64 when generating -mlittle it requires -mabi=elfv2 to generate v2 ABI. This change adds ABI annotations together with endianness. The kernel with ELFv2 ABI also uses -mcall-aixdesc, but boot/ does not. Signed-off-by: Nicholas Piggin <npig...@gmail.com> --- arch/powerpc/Makefile | 7 +++++++ arch/powerpc/boot/Makefile | 1 + 2 files changed, 8 insertions(+) diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile index 617dece..8828807 100644 --- a/arch/powerpc/Makefile +++ b/arch/powerpc/Makefile @@ -73,13 +73,18 @@ MULTIPLEWORD := -mmultiple endif cflags-$(CONFIG_CPU_BIG_ENDIAN) += $(call cc-option,-mbig-endian) +cflags-$(CONFIG_CPU_BIG_ENDIAN) += $(call cc-option,-mabi=elfv1) +cflags-$(CONFIG_CPU_BIG_ENDIAN) += $(call cc-option,-mcall-aixdesc) cflags-$(CONFIG_CPU_LITTLE_ENDIAN) += -mlittle-endian +cflags-$(CONFIG_CPU_LITTLE_ENDIAN) += -mabi=elfv2 ifneq ($(cc-name),clang) cflags-$(CONFIG_CPU_LITTLE_ENDIAN) += -mno-strict-align endif aflags-$(CONFIG_CPU_BIG_ENDIAN) += $(call cc-option,-mbig-endian) +aflags-$(CONFIG_CPU_BIG_ENDIAN) += $(call cc-option,-mabi=elfv1) aflags-$(CONFIG_CPU_LITTLE_ENDIAN) += -mlittle-endian +aflags-$(CONFIG_CPU_LITTLE_ENDIAN) += -mabi=elfv2 ifeq ($(HAS_BIARCH),y) override AS += -a$(BITS) @@ -113,7 +118,9 @@ ifeq ($(CONFIG_CPU_LITTLE_ENDIAN),y) CFLAGS-$(CONFIG_PPC64) += $(call cc-option,-mabi=elfv2,$(call cc-option,-mcall-aixdesc)) AFLAGS-$(CONFIG_PPC64) += $(call cc-option,-mabi=elfv2) else +CFLAGS-$(CONFIG_PPC64) += $(call cc-option,-mabi=elfv1) CFLAGS-$(CONFIG_PPC64) += $(call cc-option,-mcall-aixdesc) +AFLAGS-$(CONFIG_PPC64) += $(call cc-option,-mabi=elfv1) endif CFLAGS-$(CONFIG_PPC64) += $(call cc-option,-mcmodel=medium,$(call cc-option,-mminimal-toc)) CFLAGS-$(CONFIG_PPC64) += $(call cc-option,-mno-pointers-to-nested-functions) diff --git a/arch/powerpc/boot/Makefile b/arch/powerpc/boot/Makefile index eae2dc8..1d50d41 100644 --- a/arch/powerpc/boot/Makefile +++ b/arch/powerpc/boot/Makefile @@ -33,6 +33,7 @@ BOOTCFLAGS += -m64 endif ifdef CONFIG_CPU_BIG_ENDIAN BOOTCFLAGS += -mbig-endian +BOOTCFLAGS += $(call cc-option,-mabi=elfv1) else BOOTCFLAGS += -mlittle-endian BOOTCFLAGS += $(call cc-option,-mabi=elfv2) -- 2.10.2
