[PATCH v2 0/2] Add board-id support for multiple DT selection

Krzysztof Kozlowski krzysztof.kozlowski at linaro.org
Thu Mar 28 01:50:16 PDT 2024


On 14/03/2024 13:11, Amrit Anand wrote:
> The software packages are shipped with multiple device tree blobs supporting
> multiple boards. For instance, suppose we have 3 SoC, each with 4 boards supported,
> along with 2 PMIC support for each case which would lead to total of 24 DTB files.
> Along with these configurations, OEMs may also add certain additional board variants.
> Hence, a mechanism is required to pick the correct DTB for the board on which the
> software package is deployed. Introduce a unique property for adding board identifiers
> to device trees. Here, board-id property provides a mechanism for Qualcomm based
> bootloaders to select the appropriate DTB.
> 
> Isn't that what the compatible property is for?
> -----------------------------------------------
> The compatible property can be used for board matching, but requires
> bootloaders and/or firmware to maintain a database of possible strings
> to match against or have complex compatible string parsing and matching.
> Compatible string matching becomes complicated when there are multiple
> versions of the same board. It becomes difficult for the device tree
> selection mechanism to recognize the right DTB to pick, with minor
> differences in compatible strings.
> 
> The solution proposed here is simpler to implement and doesn't require the need
> to update bootloader for every new board.

One of the concerns you got in v1 was: show us second user, so I believe
in your interest is to Cc other platform maintainers which could support
this idea.

Best regards,
Krzysztof




More information about the linux-riscv mailing list