Karthik Ramasubramanian has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/40531 )
Change subject: mb/google/dedede: Remove pad termination for RAM_STRAP_4 ......................................................................
Patch Set 1:
(1 comment)
https://review.coreboot.org/c/coreboot/+/40531/1//COMMIT_MSG Commit Message:
https://review.coreboot.org/c/coreboot/+/40531/1//COMMIT_MSG@10 PS1, Line 10: Remove the internal pull-up.
What is the impact of doing this? Does this mean that we cannot really guarantee whether single or d […] What is the impact of doing this? Does this mean that we cannot really guarantee whether single or dual channel configuration is being used?
On boards where the strap is not stuffed, we cannot really guarantee whether single or dual channel config is being used.
Are all boards for the current board version have both channels populated?
All the current board versions have both channels populated.
If yes, do we need to have a workaround in coreboot to ensure it behaves correctly?
One work-around that I can think of is, if the GPIO is reading as 0 and CBI is not populated then fallback to the dual channel configuration. Else use single channel configuration.
If GPIO is reading as 1, then use dual-channel configuration.