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| author | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2005-05-03 15:34:58 +1000 |
|---|---|---|
| committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-05-03 07:38:34 -0700 |
| commit | 52292c9b8c16aa9024a65aaeeca434bb8fec7d24 (patch) | |
| tree | 59c7aae8cab7c4e1e557dd3a4fff6afbffab38e2 /arch/ppc64 | |
| parent | 6628465e33ca694bd8fd5c3cf4eb7ff9177bc694 (diff) | |
| download | talos-obmc-linux-52292c9b8c16aa9024a65aaeeca434bb8fec7d24.tar.gz talos-obmc-linux-52292c9b8c16aa9024a65aaeeca434bb8fec7d24.zip | |
[PATCH] ppc64: fix gcc 4.0 vs CONFIG_ALTIVEC
gcc-4.0 generates altivec code implicitly when -mcpu indicates an
altivec capable CPU which is not suitable for the kernel. However, we
used to set -mcpu=970 when CONFIG_ALTIVEC was set because a gcc-3.x bug
prevented from using -maltivec along with -mcpu=power4, thus prevented
building the RAID6 altivec code.
This patch fixes all of this by testing for the gcc version. If 4.0 or
later, just normally use -mcpu=power4 and let the RAID6 code add
-maltivec to the few files it needs to be compiled with altivec support.
For 3.x, we still use -mcpu=970 to work around the above problem, which
is fine as 3.x will never implicitly generate altivec code.
The Makefile hackery may not be the most lovely, I welcome anybody more
skilled than me to improve it.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'arch/ppc64')
| -rw-r--r-- | arch/ppc64/Makefile | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/arch/ppc64/Makefile b/arch/ppc64/Makefile index d33e20bcc52f..691f3008e698 100644 --- a/arch/ppc64/Makefile +++ b/arch/ppc64/Makefile @@ -56,13 +56,20 @@ LDFLAGS_vmlinux := -Bstatic -e $(KERNELLOAD) -Ttext $(KERNELLOAD) CFLAGS += -msoft-float -pipe -mminimal-toc -mtraceback=none \ -mcall-aixdesc +GCC_VERSION := $(call cc-version) +GCC_BROKEN_VEC := $(shell if [ $(GCC_VERSION) -lt 0400 ] ; then echo "y"; fi ;) + ifeq ($(CONFIG_POWER4_ONLY),y) ifeq ($(CONFIG_ALTIVEC),y) +ifeq ($(GCC_BROKEN_VEC),y) CFLAGS += $(call cc-option,-mcpu=970) else CFLAGS += $(call cc-option,-mcpu=power4) endif else + CFLAGS += $(call cc-option,-mcpu=power4) +endif +else CFLAGS += $(call cc-option,-mtune=power4) endif |
