Felix Held has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/43781 )
Change subject: soc/amd/picasso: don't apply unconfigured USB2 PHY tune parameters ......................................................................
Patch Set 1:
(1 comment)
https://review.coreboot.org/c/coreboot/+/43781/1//COMMIT_MSG Commit Message:
https://review.coreboot.org/c/coreboot/+/43781/1//COMMIT_MSG@11 PS1, Line 11: configured in the board's devicetree. Since all parameters being zero is
That's assuming default values are valid. They never are...
The default UPD values added in the FSP build process are certainly less wrong than setting all fields to 0. I don't expect them to be right for every possible mainboard which is probably also why the devicetree settings exist. When the settings are missing from the devicetree like currently for Mandolin, I strongly prefer having some defaults instead of writing 0 to every field. Would you prefer if the coreboot code explicitly sets the fields to the defaults from FSP when the board doesn't have the corresponding devicetree entries?