From: Nicholas Piggin <npiggin@gmail.com>
To: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org, Alan Modra <amodra@gmail.com>
Subject: Re: [PATCH 2/3] powerpc: allow compilation on cross-endian toolchain
Date: Sun, 27 Nov 2016 13:46:20 +1100 [thread overview]
Message-ID: <20161127134620.74007843@roar.ozlabs.ibm.com> (raw)
In-Reply-To: <87lgw6snp4.fsf@concordia.ellerman.id.au>
On Sat, 26 Nov 2016 18:30:15 +1100
Michael Ellerman <mpe@ellerman.id.au> wrote:
> Nicholas Piggin <npiggin@gmail.com> writes:
> > On Thu, 24 Nov 2016 00:02:08 +1100
> > 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) += $(call cc-option,-mcall-aixdesc)
>
> This blew up the world:
>
> http://kisskb.ellerman.id.au/kisskb/head/1ba4cb3d67e181bdc9a911d7be81f64e3d7597d2/
>
> Successful: 24% 63/258
>
> I suspect you need to make -mcall-aixdesc 64-bit only.
Yes, I forgot 32-bit will pick those up. 3rd time's a charm, this compiles
64 bit be/le and 32-bit now.
--
Subject: [PATCH] powerpc: allow compilation on cross-endian toolchain
GCC can compile with either endian, but the ABI version always
defaults to the default endian. Alan Modra says:
you need both -mbig and -mabi=elfv1 to make a powerpc64le gcc
generate powerpc64 code
The opposite is true for powerpc64 when generating -mlittle it
requires -mabi=elfv2 to generate v2 ABI. This change adds ABI
annotations together with endianness. The kernel with ELFv2 ABI
also uses -mcall-aixdesc, but boot/ does not.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
arch/powerpc/Makefile | 11 ++++++++++-
arch/powerpc/boot/Makefile | 4 +++-
2 files changed, 13 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile
index 617dece..a60c9c6 100644
--- a/arch/powerpc/Makefile
+++ b/arch/powerpc/Makefile
@@ -72,8 +72,15 @@ GNUTARGET := powerpc
MULTIPLEWORD := -mmultiple
endif
-cflags-$(CONFIG_CPU_BIG_ENDIAN) += $(call cc-option,-mbig-endian)
+ifdef CONFIG_PPC64
+cflags-$(CONFIG_CPU_BIG_ENDIAN) += $(call cc-option,-mabi=elfv1)
+cflags-$(CONFIG_CPU_BIG_ENDIAN) += $(call cc-option,-mcall-aixdesc)
+aflags-$(CONFIG_CPU_BIG_ENDIAN) += $(call cc-option,-mabi=elfv1)
+aflags-$(CONFIG_CPU_LITTLE_ENDIAN) += -mabi=elfv2
+endif
+
cflags-$(CONFIG_CPU_LITTLE_ENDIAN) += -mlittle-endian
+cflags-$(CONFIG_CPU_BIG_ENDIAN) += $(call cc-option,-mbig-endian)
ifneq ($(cc-name),clang)
cflags-$(CONFIG_CPU_LITTLE_ENDIAN) += -mno-strict-align
endif
@@ -113,7 +120,9 @@ ifeq ($(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..7c46cf3 100644
--- a/arch/powerpc/boot/Makefile
+++ b/arch/powerpc/boot/Makefile
@@ -28,14 +28,16 @@ BOOTCFLAGS := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
-isystem $(shell $(CROSS32CC) -print-file-name=include) \
-D$(compress-y)
+# PPC64_BOOT_WRAPPER is little-endian specific.
ifdef CONFIG_PPC64_BOOT_WRAPPER
BOOTCFLAGS += -m64
+BOOTCFLAGS += $(call cc-option,-mabi=elfv2)
endif
+
ifdef CONFIG_CPU_BIG_ENDIAN
BOOTCFLAGS += -mbig-endian
else
BOOTCFLAGS += -mlittle-endian
-BOOTCFLAGS += $(call cc-option,-mabi=elfv2)
endif
BOOTAFLAGS := -D__ASSEMBLY__ $(BOOTCFLAGS) -traditional -nostdinc
--
2.10.2
next prev parent reply other threads:[~2016-11-27 2:46 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-11-23 13:02 [PATCH 0/3] minor build fixes Nicholas Piggin
2016-11-23 13:02 ` [PATCH 1/3] powerpc/64e: convert cmpi to cmpwi in head_64.S Nicholas Piggin
2016-11-29 12:58 ` [1/3] " Michael Ellerman
2016-11-23 13:02 ` [PATCH 2/3] powerpc: allow compilation on cross-endian toolchain Nicholas Piggin
2016-11-24 9:04 ` Nicholas Piggin
2016-11-26 3:00 ` Nicholas Piggin
2016-11-26 7:30 ` Michael Ellerman
2016-11-27 2:46 ` Nicholas Piggin [this message]
2017-02-02 8:08 ` Naveen N. Rao
2017-03-08 7:25 ` [2/3] " Michael Ellerman
2016-11-23 13:02 ` [PATCH 3/3] powerpc/64e: don't branch to dot symbols Nicholas Piggin
2016-11-29 12:58 ` [3/3] " Michael Ellerman
2016-11-23 23:03 ` [PATCH 0/3] minor build fixes Alan Modra
2016-11-24 1:04 ` Nicholas Piggin
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