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

On Fri, Oct 1, 2010 at 09:05, Ian Munsie [off-list ref] wrote:

From: Ian Munsie <redacted>

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,

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=A0 =C2=A0 Geert

--
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