Simple. Just edit the "ARCH=" line the top level Makefile or invoke make
with "make ARCH=sparc". And with 2.1 you don't even need this, as the
default value for ARCH is `uname -m`
Cross-compiling:
make ARCH=sparc CROSS_COMPILE=sparc-linux- config
make ARCH=sparc CROSS_COMPILE=sparc-linux- boot modules
That's all.
Gerd