Re: [Qemu-devel] [PATCH 4/4] IBM PowerPC 440EP Bamboo reference board emulation

[Hollis Blanchard <hollisb@us.ibm.com>]

On Tue, 2008-12-16 at 11:47 +0100, Aurelien Jarno wrote:
> On Mon, Dec 15, 2008 at 06:17:32PM -0600, Hollis Blanchard wrote:
> > Since most IO devices are integrated into the 440EP chip, "Bamboo support"
> > mostly entails implementing the -kernel, -initrd, and -append options.
> > 
> > These options are implemented by loading the guest as if u-boot had done it,
> > i.e. loading a flat device tree, updating it to hold initrd addresses, ram
> > size, and command line, and passing the FDT address in r3.
> > 
> > Since we use it with KVM, we enable the virtio block driver and include hooks
> > necessary for KVM support.
> > 
> > Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
> > ---
> > Made comment more specific.
> > ---
> >  Makefile             |    2 +-
> >  Makefile.target      |    2 +-
> >  hw/boards.h          |    1 +
> >  hw/ppc440_bamboo.c   |  190 ++++++++++++++++++++++++++++++++++++++++
> >  pc-bios/bamboo.dtb   |  Bin 0 -> 3163 bytes
> >  pc-bios/bamboo.dts   |  234 ++++++++++++++++++++++++++++++++++++++++++++++++++
> 
> I guess the .dtb file is generated from the .dts. Could you give us more
> details about that? When the tools need to generate the dtb file are
> installed on the build machine, we may want to generate the .dtb during
> the build process.

The dtb file ("device tree binary") is generated from the dts ("device
tree source") by a tool called dtc, the device tree compiler.[1]

dtc is available in major distributions: in Fedora the package name is
"dtc"; in Debian it is "device-tree-compiler" (available in testing and
unstable).

[1] http://git.jdl.com/gitweb/?p=dtc.git;a=summary

-- 
Hollis Blanchard
IBM Linux Technology Center