On Tue, 2016-01-05 at 08:58 +0100, Sascha Hauer wrote: > On Mon, Jan 04, 2016 at 07:07:27PM +0000, Trent Piepho wrote: > > Couldn't one also use the of fixup system to modify the barebox DT? In > > order to support multiple board variants, I added DT nodes that specify > > what nodes should be enabled and/or disabled for different board > > versions. An OF fixup applies this to the Linux DT. I haven't had to > > modify the barebox DT for different boards but anticipate that happening > > for the next board and I was planning to use the same system. > > I think you don't need the fixup system to accomplish that. Just hook up > to an initcall early enough and modify the barebox device tree. It > shouldn't be necessary to register a callback first and then wait for > its execution. My thought was that the fixup already registered for the Linux device tree would also cover the barebox tree, including things like oftree -l to load a new one. Calling the fixup function from an initcall wouldn't get that. I guess I'll see what happens when I need that feature. > Are you aware of device tree overlays? We planned to merge support for > them into barebox once the official device tree compiler supports them. > Unfortunately this hasn't happened yet. I thought of that, and also using include files and generating a bunch of device trees, but decided against it. It would be a lot of work to add support for generating multiple device trees into the kernel build system and buildroot which is driving everything. And then you have a pile of device tree/overlay files to keep track of. And barebox has to figure out which one to load for the kernel. So I made a system where everything is supported by one device tree. I also added support for specifying a tree to boot barebox with, hence my patches for arm boot calling convention, but decided having the xloader find a device tree fragment and pass it to the main barebox was going to be too much of a pain. Thus the one tree to rule them all solution. _______________________________________________ barebox mailing list barebox@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/barebox
