push CROSS_COMPILE out to $(ARCH)_config.mk

Each arch should handle setting a proper default CROSS_COMPILE value in
their own config.mk file rather than having to maintain a large ugly list
in the Makefile.  By using conditional assignment, we don't have to worry
about the variable already being set (env/cmdline/etc...).

The common config.mk file takes care of exporting CROSS_COMPILE already,
and while a few variables (toolchain ones) utilize CROSS_COMPILE before
including the arch config.mk, they do so with deferred assignment.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>

Makefile

@@ -151,50 +151,10 @@ ifeq ($(obj)include/config.mk,$(wildcard $(obj)include/config.mk))
 include $(obj)include/config.mk
 export	ARCH CPU BOARD VENDOR SOC
 
-ifndef CROSS_COMPILE
+# set default to nothing for native builds
 ifeq ($(HOSTARCH),$(ARCH))
-CROSS_COMPILE =
-else
-ifeq ($(ARCH),ppc)
-CROSS_COMPILE = ppc_8xx-
-endif
-ifeq ($(ARCH),arm)
-CROSS_COMPILE = arm-linux-
-endif
-ifeq ($(ARCH),i386)
-CROSS_COMPILE = i386-linux-
-endif
-ifeq ($(ARCH),mips)
-CROSS_COMPILE = mips_4KC-
-endif
-ifeq ($(ARCH),nios)
-CROSS_COMPILE = nios-elf-
-endif
-ifeq ($(ARCH),nios2)
-CROSS_COMPILE = nios2-elf-
+CROSS_COMPILE ?=
 endif
-ifeq ($(ARCH),m68k)
-CROSS_COMPILE = m68k-elf-
-endif
-ifeq ($(ARCH),microblaze)
-CROSS_COMPILE = mb-
-endif
-ifeq ($(ARCH),blackfin)
-CROSS_COMPILE = bfin-uclinux-
-endif
-ifeq ($(ARCH),avr32)
-CROSS_COMPILE = avr32-linux-
-endif
-ifeq ($(ARCH),sh)
-CROSS_COMPILE = sh4-linux-
-endif
-ifeq ($(ARCH),sparc)
-CROSS_COMPILE = sparc-elf-
-endif	# sparc
-endif	# HOSTARCH,ARCH
-endif	# CROSS_COMPILE
-
-export	CROSS_COMPILE
 
 # load other configuration
 include $(TOPDIR)/config.mk

arm_config.mk

@@ -21,6 +21,8 @@
 # MA 02111-1307 USA
 #
 
+CROSS_COMPILE ?= arm-linux-
+
 PLATFORM_CPPFLAGS += -DCONFIG_ARM -D__ARM__
 
 LDSCRIPT := $(SRCTREE)/cpu/$(CPU)/u-boot.lds

avr32_config.mk

@@ -21,5 +21,7 @@
 # MA 02111-1307 USA
 #
 
+CROSS_COMPILE ?= avr32-linux-
+
 PLATFORM_RELFLAGS	+= -ffixed-r5 -fPIC -mno-init-got -mrelax
 PLATFORM_LDFLAGS	+= --relax

blackfin_config.mk

@@ -21,6 +21,8 @@
 # MA 02111-1307 USA
 #
 
+CROSS_COMPILE ?= bfin-uclinux-
+
 CONFIG_BFIN_CPU := $(strip $(subst ",,$(CONFIG_BFIN_CPU)))
 CONFIG_BFIN_BOOT_MODE := $(strip $(subst ",,$(CONFIG_BFIN_BOOT_MODE)))
 CONFIG_ENV_OFFSET := $(strip $(subst ",,$(CONFIG_ENV_OFFSET)))

i386_config.mk

@@ -21,4 +21,6 @@
 # MA 02111-1307 USA
 #
 
+CROSS_COMPILE ?= i386-linux-
+
 PLATFORM_CPPFLAGS += -DCONFIG_I386 -D__I386__

m68k_config.mk

@@ -21,5 +21,7 @@
 # MA 02111-1307 USA
 #
 
+CROSS_COMPILE ?= m68k-elf-
+
 PLATFORM_CPPFLAGS += -DCONFIG_M68K -D__M68K__
 PLATFORM_LDFLAGS  += -n

microblaze_config.mk

@@ -24,4 +24,6 @@
 # MA 02111-1307 USA
 #
 
+CROSS_COMPILE ?= mb-
+
 PLATFORM_CPPFLAGS += -ffixed-r31 -D__microblaze__

mips_config.mk

@@ -21,6 +21,8 @@
 # MA 02111-1307 USA
 #
 
+CROSS_COMPILE ?= mips_4KC-
+
 PLATFORM_CPPFLAGS += -DCONFIG_MIPS -D__MIPS__
 
 #

nios2_config.mk

@@ -22,5 +22,7 @@
 # MA 02111-1307 USA
 #
 
+CROSS_COMPILE ?= nios2-elf-
+
 PLATFORM_CPPFLAGS += -DCONFIG_NIOS2 -D__NIOS2__
 PLATFORM_CPPFLAGS += -ffixed-r15 -G0

nios_config.mk

@@ -22,4 +22,6 @@
 # MA 02111-1307 USA
 #
 
+CROSS_COMPILE ?= nios-elf-
+
 PLATFORM_CPPFLAGS += -m32 -DCONFIG_NIOS -D__NIOS__ -ffixed-g7 -gstabs

ppc_config.mk

@@ -21,6 +21,8 @@
 # MA 02111-1307 USA
 #
 
+CROSS_COMPILE ?= ppc_8xx-
+
 PLATFORM_CPPFLAGS += -DCONFIG_PPC -D__powerpc__
 PLATFORM_LDFLAGS  += -n
 

sh_config.mk

@@ -21,6 +21,8 @@
 # MA 02111-1307 USA
 #
 
+CROSS_COMPILE ?= sh4-linux-
+
 PLATFORM_CPPFLAGS += -DCONFIG_SH -D__SH__
 PLATFORM_LDFLAGS += -e $(TEXT_BASE) --defsym reloc_dst=$(TEXT_BASE)
 

sparc_config.mk

@@ -21,4 +21,6 @@
 # MA 02111-1307 USA
 #
 
+CROSS_COMPILE ?= sparc-elf-
+
 PLATFORM_CPPFLAGS += -DCONFIG_SPARC -D__sparc__