On 14/02/2024 13:56, Amrit Anand wrote: > On 2/2/2024 10:30 AM, Amrit Anand wrote: > <snip> >>> There's a similar issue for EFI boot with how to select an OS installed >>> DTB[1]. You might not care now, but users may later on (like we have >>> already with QCom devices with fixed bootloaders). If you do this >>> board-id route, then no doubt that compatible values won't be specific >>> enough or have suitable fallbacks to be used. Then EFI boot can't use >>> compatible either and needs to use this QCom specific logic. It may be a >>> common property name, but all the types you defined are QCom specific >>> and the matching logic is pretty much undocumented. I'm not saying we >>> have to use compatible. There wasn't even agreement to use it for EFI >>> boot case. This does need to work for multiple vendors and multiple boot >>> scenarios. >>> >> Agree, given so many hardware identifiers Qcom uses to find the DT >> based on a best and exact match algorithm, it may not work as is for >> other vendors/users outside the scope of Qcom. >> Since we have none to very limited visibility into complete set of DT >> selection identifiers being used by other users or into their >> selection algorithms since it is mostly undocumented, >> designing a perfectly generic solution (one-size-fits-all) could be >> far-fetched. The number of board files in Qcom DT selection software >> package often reaches over 100 DT files due to multiple SoCs and >> board types being supported out of a single software package and these >> multiple hardware identifiers helps to pick the closest best match DT >> within a very large pool of DTs. >> Not to affect other users/vendors who would be using their own set of >> identifiers and an entirely different algorithm for DT selection, >> would it make more sense to define these Qcom specific >> identifiers within Qcom specific bindings (qcom.yaml), along with >> detailed documentation on our DT selection algorithm? > > > I have written a patch for defining Qcom specific identifiers within > Qcom specific bindings (qcom.yaml) along with documentation on DT > selection algorithm, would it be okay to send for review? New ideas and patches in good-faith are always welcomed for review, so go ahead. What's still missing here is involvement of other SoC vendors: at least their maintainers and mailing lists. Best regards, Krzysztof
