Re: [PATCH 18/18] arm64: apple: Add initial Mac Mini 2020 (M1) devicetree

From: Hector Martin 'marcan'
Date: Fri Feb 05 2021 - 02:14:36 EST


On 05/02/2021 08.08, Arnd Bergmann wrote:
On Thu, Feb 4, 2021 at 10:44 PM Hector Martin 'marcan' <marcan@xxxxxxxxx> wrote:
On 05/02/2021 06.29, Arnd Bergmann wrote:
On Thu, Feb 4, 2021 at 9:39 PM Hector Martin <marcan@xxxxxxxxx> wrote:

We tend to split the dts file into one file per SoC and one for the
specific board. I guess in this case the split can be slightly different,
but it does feel better to be prepared for sharing a lot of the contents
between the different products.

In most cases, you'd want the 'aliases' and 'chosen' nodes to be
in the board specific file.

I thought about that, but wasn't sure if splitting it up at this early
stage made much sense since I'm not sure what the split should be, given
all supported hardware is the same for all 3 released devices.

I'm happy to throw the aliases/chosen nodes into board specific files if
you think that's a good starting point. Perhaps /memory too? Those
properties are filled in/patched by the bootloader anyway...

Yes, I think that would help make it more consistent with other
platforms even if we don't care too much here.

Ack, I'll split it up for v2.

We don't really have overlays in the kernel sources (yet), though it
is something that keeps coming up. For the moment, I'd just
assume you can have one .dts file for each thing you want to
support and keep the shared bits in .dtsi files.

No problem. We'll experiment with overlays in m1n1 and see how that goes.

One thing I wanted to ask: is there some kind of "experimental" policy for DT bindings? At early platform bring-up stages it seems like it could be valuable to allow for breaking DT changes while we flesh out the details (this is especially true of a reverse engineered platform like this, where we don't have knowledge of all the hardware details a priori). The dozen or so users we might have at this stage obviously won't complain too much :)

--
Hector Martin "marcan" (marcan@xxxxxxxxx)
Public Key: https://mrcn.st/pub