Index: kernel/arch/ppc64/Makefile.inc
===================================================================
--- kernel/arch/ppc64/Makefile.inc	(revision 46d8eb9b258c351fc7a0ec7a45162776b8adc3a2)
+++ kernel/arch/ppc64/Makefile.inc	(revision 42a0607ecb65ef66c5e86b96e979d08e140d3a70)
@@ -30,9 +30,13 @@
 #
 
+ifndef CROSS_PREFIX
+	CROSS_PREFIX = /usr/local
+endif
+
 BFD_NAME = elf64-powerpc
 BFD_ARCH = powerpc:common64
 BFD = binary
 TARGET = ppc64-linux-gnu
-TOOLCHAIN_DIR = /usr/local/ppc64
+TOOLCHAIN_DIR = $(CROSS_PREFIX)/ppc64
 
 GCC_CFLAGS += -mcpu=powerpc64 -msoft-float -m64