[PATCH 1/2] qemu platform, v2

[Grant Likely]

On 9/30/07, David Gibson <david at gibson.dropbear.id.au> wrote:
> On Fri, Sep 28, 2007 at 06:53:28PM +0200, Segher Boessenkool wrote:
> > >> I'd be following this more closely if compiling a device tree didn't
> > >> currently
> > >> require an external utility (dtc or some such) that doesn't come with
> > >> the
> > >> Linux kernel.  No other target platform I've built kernels for
> > >> requires such
> > >> an environmental dependency.
> > >
> > > No?  You haven't built kernels for other platforms that have external
> > > dependencies such as perl, gcc, make, binutils, etc.? :)
> >
> > Two of the supported Linux archs cannot be built with a mainline
> > compiler, even!
> >
> > And I have to install GNU sed/awk to get builds to work, too.
> >
> > OTOH, it would be nice if we didn't need DTC -- it itself doesn't
> > build out-of-the-box on all systems, either ;-)
> >
> > >>  (This is a problem both for hardwiring the
> > >> device tree into the kernel and for building a new boot rom from the
> > >> linux
> > >> kernel's ppc boot wrapper that would contain such a device tree to
> > >> feed to
> > >> the kernel.)
> > >
> > > It's only really been a problem for ps3 so far, since the embedded
> > > guys don't seem to have any difficulty with installing dtc.  We are
> > > looking at what to do for ps3 and prep, and the answer may well
> > > involve bundling dtc in the kernel source (it's not too big, around
> > > 3400 lines).
> >
> > If only a few platforms have this problem, we could instead include
> > their .dtb files in the kernel source tree.
>
> Including .dtbs in the kernel tree has a big practical problem:
> they're binary, so can't be patch(1)ed, which makes updating them a
> complete PITA.
>
> I'm working on merging dtc into the kernel tree instead.

I'm kind of late to this party; but I have to say I disagree.  Most of
us are doing just fine installing the dtc tool (and mkimage tool for
that matter).  Cloning it in the kernel tree is just asking for
divergence.

Cheers,
g.

-- 
Grant Likely, B.Sc., P.Eng.
Secret Lab Technologies Ltd.
grant.likely at secretlab.ca
(403) 399-0195