From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tom Rini Date: Fri, 7 Oct 2016 16:42:40 -0400 Subject: [U-Boot] [PATCH 0/9] Switch bcm283x platform to use OF_CONTROL In-Reply-To: <87shs87os3.fsf@eliezer.anholt.net> References: <20160926122651.22132-1-fvogt@suse.com> <18FBD080-6E6A-42BB-AAF4-36A626E3E3F1@suse.de> <871sztw9xf.fsf@eliezer.anholt.net> <5195146.vhkPzrWSSn@pebbles.site> <87shs87os3.fsf@eliezer.anholt.net> Message-ID: <20161007204240.GK4884@bill-the-cat> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On Thu, Oct 06, 2016 at 09:42:52PM -0700, Eric Anholt wrote: > Stefan Bruens writes: > > > On Donnerstag, 6. Oktober 2016 12:32:12 CEST Eric Anholt wrote: > >> Alexander Graf writes: > >> >> Am 05.10.2016 um 18:48 schrieb Fabian Vogt : > >> >> > >> >> Hi, > >> >> > >> >> Am Mittwoch, 5. Oktober 2016, 09:54:46 CEST schrieb Stephen Warren: > >> >>> On 09/26/2016 06:26 AM, Fabian Vogt wrote: > >> >>>> This patch series modifies the used drivers to work with OF_CONTROL > >> >>>> and switches the board code and configs to use it. > >> >>>> The added device trees are directly from the linux kernel tree > >> >>>> and can thus be used for booting the (upstream) kernel. > >> >>> > >> >>> Is there a user-visible or developer-visible benefit to this change? In > >> >>> general, converting to use DT to instantiate devices simply ends up > >> >>> using more code (and hence complexity and time) to get to the exact same > >> >>> state afterwards. > >> >> > >> >> There are various reasons, like: > >> >> > >> >> - The device tree describes the platform, so it can also be used by the > >> >> > >> >> linux kernel for configuration (no separate dtb needed) > >> > > >> > With a bit of lobbying, we might even be able to get a working dt from > >> > the rpi firmware. That again would enable awesome things like hat > >> > support in u-boot :). > >> > >> I can't imagine the firmware handing any DT off to the kernel other than > >> the one that's being shipped from whatever kernel is being loaded. > >> Being able to update the DT in lockstep with the kernel is very much > >> part of their process. (This makes linux insisting that DT is ABI that > >> must maintain backwards compat quite painful for upstreaming) > >> > >> Given that the firmware already hands the kernel's DT back to the > >> kernel, it seems like we should be able to load the kernel's DT too if > >> we wanted that. > > > > You mean the DT modified by the firmware according to config.txt, at least > > applying the specified DT overlays? > > Yeah, that. That would also be a good thing, yes. -- Tom -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 819 bytes Desc: Digital signature URL: