Re: [PATCH 02/18] powerpc: Add CROSSBE_COMPILE to build big endian boot wrapper

Geert Uytterhoeven
2010-10-01T07:13:21Z

On Fri, Oct 1, 2010 at 09:05, Ian Munsie <imunsie@au1.ibm.com> wrote:
> From: Ian Munsie <imunsie@au1.ibm.com>
>
> Since the boot wrapper must be built by a big endian 32bit toolchain
> regardless of what the rest of the kernel is using introduce a new
> parameter to specify that toolchain - CROSSBE_COMPILE.
>
> We already have CROSS32_COMPILE which is already used for the boot
> wrapper, but it is also used to build the 32bit vdso which should be
> build in the same endianness as the rest of the kernel, so it is
> necessary to be able to specify the toolchain to build the boot wrapper
> separately from that used to build the vdso and again separately from
> that used to build the main kernel.
>
> CROSSBE_COMPILE should be pointed to a toolchain capable of targeting
> 32bit big endian powerpc, either specifically targetted at 32bit or
> bi-arch 64 and 32bit. If CROSSBE_COMPILE is not specified it will fall
> back to CROSS32_COMPILE to maintain compatibility with big endian
> targets.

Shouldn't the help text added by [PATCH 01/18]:

+++ b/arch/powerpc/platforms/Kconfig.cputype
@@ -329,3 +329,19 @@ config CHECK_CACHE_COHERENCY
bool

endmenu
+
+config ARCH_SUPPORTS_LITTLE_ENDIAN
+ bool
+
+config CPU_LITTLE_ENDIAN
+ bool "Build little endian kernel"
+ depends on ARCH_SUPPORTS_LITTLE_ENDIAN && EXPERIMENTAL
+ default n
+ help
+ This option selects whether a big endian or little endian kernel will
+ be built.
+
+ Note that if building a little endian kernel, CROSS_COMPILE must
+ point to a toolchain capable of targetting little endian powerpc,
+ while the toolchain specified by CROSS32_COMPILE must be capable of
+ targetting *BIG* endian PowerPC.

be updated here as well?

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds