[U-Boot] [PATCH 1/2 V2] mips: add endianness support

[Shinya Kuribayashi <skuribay@pobox.com>]

Hi,

Jean-Christophe PLAGNIOL-VILLARD wrote:
> curently we need to specify the endian of each board in the LDS
> 
> in order to unify all of them add full endianness support
> 
> by default the mips platforms will be compiled as big-endian
> to compile it as little-endian define CONFIG_CPU_LITTLE_ENDIAN
> 
> Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
> ---
>  Makefile                   |    2 ++
>  board/dbau1x00/u-boot.lds  |    5 +----
>  board/gth2/u-boot.lds      |    5 +----
>  board/incaip/u-boot.lds    |    5 +----
>  board/pb1x00/u-boot.lds    |    5 +----
>  board/purple/u-boot.lds    |    5 +----
>  board/qemu-mips/u-boot.lds |    5 +----
>  board/tb0229/u-boot.lds    |    3 +--
>  cpu/mips/config.mk         |    9 ---------
>  examples/Makefile          |    1 +
>  examples/mips.lds          |    5 +----
>  mips_config.mk             |   25 +++++++++++++++++++++++++
>  12 files changed, 36 insertions(+), 39 deletions(-)

[snip]

> diff --git a/cpu/mips/config.mk b/cpu/mips/config.mk
> index a173c54..928b7d8 100644
> --- a/cpu/mips/config.mk
> +++ b/cpu/mips/config.mk
> @@ -28,12 +28,3 @@ else \
>  	echo "-march=4kc -mtune=4kc"; \
>  fi)
>  
> -ifneq (,$(findstring 4KCle,$(CROSS_COMPILE)))
> -ENDIANNESS = -EL
> -else
> -ENDIANNESS = -EB
> -endif
> -
> -MIPSFLAGS += $(ENDIANNESS)

This is ok, but

> -
> -PLATFORM_CPPFLAGS += $(MIPSFLAGS)

I think this wrongly removes -march=4kc -mtune=4kc.

> diff --git a/mips_config.mk b/mips_config.mk
> index 05eb05d..423e216 100644
> --- a/mips_config.mk
> +++ b/mips_config.mk
> @@ -46,3 +46,28 @@ PLATFORM_CPPFLAGS += -DCONFIG_MIPS -D__MIPS__
>  PLATFORM_CPPFLAGS		+= -G 0 -mabicalls -fpic
>  PLATFORM_CPPFLAGS		+= -msoft-float
>  PLATFORM_LDFLAGS		+= -G 0 -static -n -nostdlib
> +
> +#
> +# We explicitly add the endianness specifier if needed, this allows
> +# to compile kernels with a toolchain for the other endianness. We
> +# carefully avoid to add it redundantly because gcc 3.3/3.4 complains
> +# when fed the toolchain default!
> +#
> +# Certain gcc versions upto gcc 4.1.1 (probably 4.2-subversion as of
> +# 2006-10-10 don't properly change the predefined symbols if -EB / -EL
> +# are used, so we kludge that here.  A bug has been filed at
> +# http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29413.
> +#
> +
> +UNDEF_ALL += -UMIPSEB -U_MIPSEB -U__MIPSEB -U__MIPSEB__
> +UNDEF_ALL += -UMIPSEL -U_MIPSEL -U__MIPSEL -U__MIPSEL__
> +PREDEF_BE += -DMIPSEB -D_MIPSEB -D__MIPSEB -D__MIPSEB__
> +PREDEF_LE += -DMIPSEL -D_MIPSEL -D__MIPSEL -D__MIPSEL__
> +
> +ifdef CONFIG_CPU_LITTLE_ENDIAN
> +PLATFORM_CPPFLAGS += $(shell $(CC) -dumpmachine |grep -q 'mips.*el-.*' || echo -EL $(UNDEF_ALL) $(PREDEF_LE))
> +PLATFORM_LDFLAGS += -EL
> +else
> +PLATFORM_CPPFLAGS += $(shell $(CC) -dumpmachine |grep -q 'mips.*el-.*' && echo -EB $(UNDEF_ALL) $(PREDEF_BE))
> +PLATFORM_LDFLAGS += -EB
> +endif

Thanks for resubmitting, but there's one thing I'm warried about.
when I gave it a try last time, with almost the same patch you did,
I had a GNU make problem.  I'll look closely into it, so please
wait for some time.

  Shinya