[ARM PATCH] 1538/1: arch/arm/Makefile and KConfig Big-Endian changes

Patch from Deepak Saxena

This patch adds some hooks to arch/arm/Makefile to enable proper building
of big-endian kernels.  It also adds an option to the the top level
arm KConfig that only allows a big-endian kernel to be built if the sub-arch
KConfig sets the CONFIG_ARCH_SUPPORTS_BIG_ENDIAN boolean to true. This is
mainly there to keep people from attemtpting to build a big-endian kernel
for a system that is not capable of running in big-endian mode.

arch/arm/Kconfig

@@ -377,6 +377,15 @@ config ARM_THUMB
 
 	  If you don't know what this all is, saying Y is a safe choice.
 
+config CPU_BIG_ENDIAN
+	bool "Build big-endian kernel"
+	depends on ARCH_SUPPORTS_BIG_ENDIAN
+	help
+	  Say Y if you plan on running a kernel in big-endian mode.
+	  Note that your board must be properly built and your board
+	  port must properly enable and big-endian related features
+	  of your chipset/board/processor.
+
 config CPU_ICACHE_DISABLE
 	bool "Disable I-Cache"
 	depends on CPU_ARM920T || CPU_ARM922T || CPU_ARM926T || CPU_ARM1020

arch/arm/Makefile

@@ -24,6 +24,12 @@ ifeq ($(CONFIG_DEBUG_INFO),y)
 CFLAGS		+=-g
 endif
 
+ifeq ($(CONFIG_CPU_BIG_ENDIAN),y)
+CFLAGS		+= -mbig-endian
+AS		+= -EB
+LD		+= -EB
+endif
+
 # Select CPU dependent flags.  Note that order of declaration is important;
 # the options further down the list override previous items.
 #
@@ -76,7 +82,11 @@ endif
 ifeq ($(CONFIG_CPU_32),y)
 PROCESSOR	:= armv
 head-y		:= arch/arm/kernel/head.o arch/arm/kernel/init_task.o
-LDFLAGS_BLOB	+= --oformat elf32-littlearm
+  ifeq ($(CONFIG_CPU_BIG_ENDIAN),y)
+    LDFLAGS_BLOB	+= --oformat elf32-bigarm
+  else
+    LDFLAGS_BLOB	+= --oformat elf32-littlearm
+  endif
 textaddr-y	:= 0xC0008000
 endif