If no cross compiler is specified, try to auto detect one.
Look for various combinations, matching:
powerpc(64(le)?)?(-unknown)?-linux(-gnu)?-
There are more possibilities, but the above is known to find a compiler
on Fedora and Ubuntu (which use linux-gnu-), and also detects the
kernel.org cross compilers (which use linux-).
This allows cross compiling with simply:
# Ubuntu
$ sudo apt install gcc-powerpc-linux-gnu
# Fedora
$ sudo dnf install gcc-powerpc64-linux-gnu
$ make ARCH=powerpc defconfig
$ make ARCH=powerpc -j 4
Inspired by arch/parisc/Makefile.
Acked-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231206115548.1466874-4-mpe@ellerman.id.au
# Rewritten by Cort Dougan and Paul Mackerras
#
+ifdef cross_compiling
+ ifeq ($(CROSS_COMPILE),)
+ # Auto detect cross compiler prefix.
+ # Look for: (powerpc(64(le)?)?)(-unknown)?-linux(-gnu)?-
+ CC_ARCHES := powerpc powerpc64 powerpc64le
+ CC_SUFFIXES := linux linux-gnu unknown-linux-gnu
+ CROSS_COMPILE := $(call cc-cross-prefix, $(foreach a,$(CC_ARCHES), \
+ $(foreach s,$(CC_SUFFIXES),$(a)-$(s)-)))
+ endif
+endif
+
HAS_BIARCH := $(call cc-option-yn, -m32)
# Set default 32 bits cross compilers for vdso and boot wrapper