This patch adds an option to use XZ compression for the kernel image.
Currently this is only enabled for 64-bit Book3S targets, which is
roughly equivalent to the platforms that use the kernel's zImage
wrapper, and that have been tested.
The bulk of the 32-bit platforms and 64-bit BookE use uboot images,
which relies on uboot implementing XZ. In future we can enable XZ
support for those targets once someone has tested it.
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Currently the powerpc boot wrapper has its own wrapper around zlib to
handle decompressing gzipped kernels. The kernel decompressor library
functions now provide a generic interface that can be used in the
pre-boot environment. This allows boot wrappers to easily support
different compression algorithms. This patch converts the wrapper to use
this new API, but does not add support for using new algorithms.
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>