Someone

--- classes/kernel-arch.bbclass bc087fcf76549ca28fef463566ac9a3f46a3d703
+++ classes/kernel-arch.bbclass a483a48991725bddaa414801e036e80ca754b603
@@ -30,3 +30,11 @@ export ARCH = "${@map_kernel_arch(bb.dat
                bb.error("cannot map '%s' to a linux kernel architecture" % a)
 
 export ARCH = "${@map_kernel_arch(bb.data.getVar('TARGET_ARCH', d, 1), d)}"
+
+def map_uboot_arch(a, d):
+       if a == "powerpc":
+               return "ppc"
+       return a
+
+export UBOOT_ARCH = "${@map_uboot_arch(bb.data.getVar('ARCH', d, 1), d)}"
+