[Buildroot] [PATCH v1 3/9] board/intel/common: Add possibility for adding ACPI tables to the initrd
Thomas Petazzoni
thomas.petazzoni at free-electrons.com
Fri Aug 26 09:30:22 UTC 2016
Hello,
On Fri, 26 Aug 2016 12:04:54 +0300, Mika Westerberg wrote:
> > On 25-08-16 16:04, Andy Shevchenko wrote:
> > > Add script which takes ASL files as input, compiles them to AML bytecode,
> > > and prepends the whole thing to the initrd archive. They are placed in
> > > kernel/firmware/acpi directory where the kernel is able to find and use
> > > them.
> >
> > Why is this a post-image script, and not just a post-build script that copies
> > everything in the right place and lets the cpio rootfs take care of generating
> > the cpio? AFAIK there is no particular requirement for this stuff to be at the
> > beginning of the cpio image, is there?
>
> Actually there is - the kernel looks only from the first uncompressed
> cpio archive for these additional AML files.
Still not clear: Arnout doesn't suggest to generate multiple cpio
archives, but rather to simply have the AML files within the cpio
archive in the first place.
The Buildroot process looks like this:
1. Build all packages
2. Run post-build scripts
3. Create filesystem images (including cpio one)
4. Run post-image scripts
Right now, if I understand correctly, in step (4), you're generating an
additional initrd with just the AML files. Is this correct?
What about instead having things done in step (2): install the AML
files at the appropriate places in $(TARGET_DIR) so that they
automatically end up in the rootfs.cpio generated by Buildroot?
In this case, there's a single initrd, which contains both the root
filesystem itself and the AML files.
Best regards,
Thomas
--
Thomas Petazzoni, CTO, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com
More information about the buildroot
mailing list