diff options
Diffstat (limited to 'scripts/Makefile.lib')
| -rw-r--r-- | scripts/Makefile.lib | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index 396da16aabf8..1c702ca8aac8 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -262,6 +262,34 @@ cmd_lzo = (cat $(filter-out FORCE,$^) | \ lzop -9 && $(call size_append, $(filter-out FORCE,$^))) > $@ || \ (rm -f $@ ; false) +# XZ +# --------------------------------------------------------------------------- +# Use xzkern to compress the kernel image and xzmisc to compress other things. +# +# xzkern uses a big LZMA2 dictionary since it doesn't increase memory usage +# of the kernel decompressor. A BCJ filter is used if it is available for +# the target architecture. xzkern also appends uncompressed size of the data +# using size_append. The .xz format has the size information available at +# the end of the file too, but it's in more complex format and it's good to +# avoid changing the part of the boot code that reads the uncompressed size. +# Note that the bytes added by size_append will make the xz tool think that +# the file is corrupt. This is expected. +# +# xzmisc doesn't use size_append, so it can be used to create normal .xz +# files. xzmisc uses smaller LZMA2 dictionary than xzkern, because a very +# big dictionary would increase the memory usage too much in the multi-call +# decompression mode. A BCJ filter isn't used either. +quiet_cmd_xzkern = XZKERN $@ +cmd_xzkern = (cat $(filter-out FORCE,$^) | \ + sh $(srctree)/scripts/xz_wrap.sh && \ + $(call size_append, $(filter-out FORCE,$^))) > $@ || \ + (rm -f $@ ; false) + +quiet_cmd_xzmisc = XZMISC $@ +cmd_xzmisc = (cat $(filter-out FORCE,$^) | \ + xz --check=crc32 --lzma2=dict=1MiB) > $@ || \ + (rm -f $@ ; false) + # misc stuff # --------------------------------------------------------------------------- quote:=" |