Barebox device tree overlay support

[Sascha Hauer]

On Fri, Jan 12, 2018 at 11:11:32AM +0100, Maxime Ripard wrote:
> Hi,
> 
> On Fri, Jan 12, 2018 at 08:42:26AM +0100, Sascha Hauer wrote:
> > On Thu, Jan 11, 2018 at 03:40:49PM +0000, Dgien, David [US] (MS) wrote:
> > > Hello,
> > > 
> > > When going through the archives it looks like a set of patches
> > > were submitted to support device tree overlays in barebox in
> > > http://lists.infradead.org/pipermail/barebox/2015-March/022674.html.
> > > But they weren't accepted because overlays weren't fully
> > > implemented in the DTC yet.
> > > 
> > > It looks like overlay support was mainlined in the kernel in
> > > 4.11. ( kernel/git/torvalds/linux.git:
> > > be5165a51d2500ae1afa1236a8b09858831fdf7e )
> > 
> > I am still not sure which parts got merged and which are still pending.
> > There are still overlay patches floating around.
> 
> The only thing that's missing in the kernel at the moment is a
> user-space interface to load overlays, but the rest has been there for
> quite some time.
> 
> > > Would it be possible to take another look at pulling these patches
> > > into the barebox mainline?
> > 
> > Generally yes. If you like, please rebase test and respin the patches.
> 
> The libfdt gained support to apply overlays quite some time ago
> already, so this should be as easy as updating it to a recent enough
> version, and creating a wrapper around fdt_apply. This is what U-Boot
> is doing.

barebox does not use libfdt.

Sascha

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