Re: [PATCH] ARM: dts: aspeed: Add dts for ASUS Kommando IPMI card

[Andrew Jeffery <andrew@codeconstruct.com.au>]

Hi Anirudh,

Sorry for the delay in reply to this thread.

On Sat, 2026-03-21 at 17:24 -0500, Anirudh Srinivasan wrote:
> Helo Andrew,
> 
> After doing some more reading and experimentation, I think I might
> have a clearer understanding of how things work.
> 
> Andrew Lunn's suggestion in the patch series from Aspeed was to patch
> u-boot to not insert clock delays anymore. And then use rgmii-id as
> the phy mode in u-boot and linux for all new device trees.
> 
> I tested this by setting the mac2 clk delays to 0 in the u-boot device
> tree like this
> 
> &scu {
>     mac2-clk-delay = <0 0
>               0 0
>               0 0>;
> };
> 
> Setting the phy-mode to rgmii-id now gives us working networking in
> u-boot and linux.
> 
> So how do you suggest we proceed here?
> 1. Add this DT to u-boot now, set phy mode to rgmii-id and set
> mac2-clk-delay values to 0. Networking will work in u-boot and linux.
> Update the DT to remove the clk delay values once Aspeed updates
> u-boot
> 2. Add this DT to u-boot now. set phy mode to rgmii-id. This means
> networking won't work in u-boot, but it works once you're in linux
> 3. Add this DT to u-boot now without networking. Add networking later
> when Aspeed updates u-boot based on the discussion in that thread.
> 3. Wait for aspeed to update u-boot, then add this DT to u-boot.
> 
> In any of these cases, we can also now add networking to the linux DT
> for this card (it's missing currently) with phy-mode set to rgmii-id.
> No need to wait for Aspeed to update the linux driver (or I think
> they're not gonna make any updates at all if it's just u-boot that
> needs fixing).

Working backwards here, yes, I think we should add the correct (but not
necessarily yet functional) description to the linux devicetree
(probably best to point out the lack of functionality in a comment in
the relevant devicetree node). 

Then, do your first option 3 above, except add the description of
option 1 in the commit message so people understand how to make
networking function for both environments. That way it's apparent that
anyone who has enabled networking in u-boot is also aware of the
(future) problems of doing so, as they likely will have read that
description. Please add links to the relevant discussions between
Andrew Lunn and Jacky to the commit message as well.

Any concerns with that approach?

> 
> Let me know what you think (or if I've gotten any info incorrect here).

That all sounds about right to me.

Andrew