Attention is currently required from: Angel Pons, Fabian Meyer, Paul Menzel.
Nico Huber has posted comments on this change by Fabian Meyer. ( https://review.coreboot.org/c/coreboot/+/82203?usp=email )
Change subject: mb/asrock: Add SPR 1S server board ASRock Rack SPC741D8-2L2T/BCM ......................................................................
Patch Set 9: Code-Review+1
(2 comments)
Patchset:
PS9: I guess we can just merge this without the FSP-header update. One would only have to update the include path in menuconfig to build, right? WDYT?
File src/mainboard/asrock/spc741d8/ramstage.c:
https://review.coreboot.org/c/coreboot/+/82203/comment/87e19851_5d494707?usp... : PS3, Line 15: // stub for EDK2
I2C is used to retrieve the EDID of connected displays. […]
The AST code actually expects CONFIG_SOFTWARE_I2C (i2c bitbanging, I suppose) to be selected. There's a ast_dp501_read_edid() on the primary path that probably gets a pre-read EDID from the AST. Only if that fails, I2C is tried. Which path is taken probably depends on the AST firmware.
SOFTWARE_I2C, however, seems to be designed as a developer option, nothing that should be selected by a driver (expect bus number conflicts if some other driver tries to use a SoC's I2C bus 0).
For this board, as we know there is no SoC I2C (i.e. no platform_i2c_transfer() implemented), the best solution might be to simply select SOFTWARE_I2C from the board Kconfig. The stub, however, will be needed anyway.
Porting SOFTWARE_I2C to our devicetree infrastructure could solve the bigger puzzle. Doesn't seem necessary for the Aspeed-using boards so far, though.