On Thu, Aug 26, 2021 at 09:35:12AM +0200, Michael Walle wrote: > Am 2021-08-26 01:03, schrieb Vladimir Oltean: > > On Wed, Aug 25, 2021 at 04:09:50PM -0400, Tom Rini wrote: > > In any case, it doesn't sound absurd at all, with a bit of passion it > > could be done on all Layerscapes. I would be absolutely glad to help on > > the Ethernet / DSA side of things (which I believe is the reason why > > Michael summoned me into this thread), > > ;) and because I thought you might be interested in the answer to the > initial question. After all, you also worked on the device trees in linux > and u-boot. > > > but I don't believe that's where > > the problem is right now. When I added the DM_DSA uclass to U-Boot I did > > my best to pick a reasonable subset of Linux DSA, and with compatible > > device tree bindings. Also maintaining the Linux side of things, I did > > provide feedback to Tim Harvey for the Microchip KSZ switches as to > > what is the subset supported by U-Boot that would also be DT-compatible > > with Linux. If it turns out that I failed at that, I am willing to > > rework what we have. > > I started to convert the u-boot device tree yesterday - and it doesn't > look too bad for now. I was already able to copy the kernel soc dtsi > and u-boot is still booting and working. > > Theres still one catch at the moment, AFAIK in linux you can put the > PHYs either in the mdio controller node or in a "mdio" subnode within > the ethernet controller node. I'm not sure wether the latter works in > u-boot, but [1] looks promising. At least, linux dtbs are using the > mdio subnodes and u-boot put the phys into the mdio controller node. Please change Linux for that, move the PHYs from the per-port MDIO node to the PF 3 central MDIO controller node. Due to hardware reasons, the per-port MDIO controller registers are in fact de-featured and should be hidden from new LS1028A reference manuals. > Maybe sharing the device tree between linux and u-boot isn't that hard > for the ls1028a after all and its just that nobody did it for now. > Renaming the reference here and there and introducing the linux > compatible strings may do it. I'll come back to you if there are > problems with ethernet (or DSA). > > -michael > > > I have been known on a few occasions to say "U-Boot does not parse this > > part of the device tree, you can just strip it away", but I will keep my > > mouth shut from now on. > > [1] https://lists.denx.de/pipermail/u-boot/2020-May/410169.html
