On Wed, Feb 18, 2015 at 8:08 PM, Frank Rowand <frowand.list@xxxxxxxxx> wrote: > On 2/18/2015 6:59 AM, Pantelis Antoniou wrote: >> Implement a method of applying DT quirks early in the boot sequence. >> >> A DT quirk is a subtree of the boot DT that can be applied to >> a target in the base DT resulting in a modification of the live >> tree. The format of the quirk nodes is that of a device tree overlay. > > The use of the word "quirk" is a different mental model for me than what > this patch series appears to be addressing. I would suggest totally > removing the word "quirk" from this proposal to avoid confusing the > mental models of future generations of kernel folks. This comes from me as quirks are a different usecase I had in mind, but one that could use a similar mechanism. Although, in the case of quirks, I would expect them to be overlays built into the kernel. It would be more a way to update old dtbs. > What this patch series seems to be proposing is a method to apply DT > overlays as soon as unflatten_device_tree() completes. In other words, > making the device tree a dynamic object, that is partially defined by > the kernel during boot. Well, to be fair, the kernel chooses among > several possible alternatives encoded in the DT blob. So the device > tree is no longer a static object that describes the hardware of the > system. It may not sound like a big deal, but it seems to me to be > a fundamental shift in what the device tree blob is. Something that > should be thought about carefully and not just applied as a patch to > solve a point problem. I agree. I would not want to see every board for an SOC become an overlay for example. I think it has to be limited to truly plugable h/w (e.g. capes) or minor changes. We just have to define what is minor. :) Rob -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
