Jeremy Soller has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/35924 )
Change subject: Revert "soc/intel/cannonlake: Remove DMA support for PTT" ......................................................................
Patch Set 3:
(1 comment)
Patch Set 2:
(1 comment)
I have updated the commit description and responded to Aaron's questions
https://review.coreboot.org/c/coreboot/+/35924/2//COMMIT_MSG Commit Message:
https://review.coreboot.org/c/coreboot/+/35924/2//COMMIT_MSG@11 PS2, Line 11: Reason for revert: Breaks boot on Whiskey Lake-U System76 boards
Why? What is the interaction? An FSP default setting for that board? Soft strap configuration? F […]
The FSP version is the one from the current master branch of coreboot, Coffee Lake 7.0.64.40. No special UPDs are being set.
PTT is enabled in the ME configuration, not in the firmware.
Here is the settings file from Intel FIT tool showing PTT enabled:
<IntelPttConfiguration label="Intel(R) PTT Configuration"> <PttSupported value="Yes" value_list="No,,Yes" label="Intel(R) PTT Supported" help_text="This setting permanently disables Intel(R) PTT in the firmware image." /> <PttPwrUpState value="Enabled" value_list="Disabled,,Enabled" label="Intel(R) PTT initial power-up state" /> <PttSupportedFpf value="Yes" value_list="No,,Yes" label="Intel(R) PTT Supported [FPF]" help_text="This setting will permanently disable Intel(R) PTT through platform FPFs. Caution: Using this option will permanently disable Intel(R) PTT on the platform hardware." /> </IntelPttConfiguration>