On 2021-12-15 06:44, AreYouLoco? wrote:
Since https://del.dog paste service is no longer operating...
I am re-sending the dumps to the mailing list as requested by Nico.
I took a look at those inteltool dumps, and they don't seem to be consistent with what the schematic shows. As Nico mentioned before, the 1394_DTCT line goes into GPIO16, according the schematic. However, the logs indicate that GPIO16 is configured for its native function, and not a GPIO. The existing coreboot code for the T420 also configures it for its native function.
Looking for pins configured as input GPIOs where the value changes between the 3 dumps yields 2 candidates: 54 and 71. Both of those pins read 0 with the Firewire board, and read 1 with no board/usb only.
According to the schematic (or at least the one I found) GPIO54 is connected to BDC_PRESENCE, and GPIO71 is not used and pulled high through a resistor. Out of those 2 GPIO71 seems more likely, but we'd need to find a way to confirm that to be sure.
Cheers, Nicholas