[coreboot] Re: Graphics Initialization

[Angel Pons]

Hi,

On Fri, Oct 4, 2019, 16:39 Michal Zygowski 
wrote:
> Hi,
>
> Search your devicetree.cb for UART PCI devices like:
>
> device pci 19.2 on  end # UART #2
> device pci 1e.0 on  end # UART #0
> device pci 1e.1 off end # UART #1
>
> As you can see above these entries describe the device.function of the
> UART and the on/off switch. Try to turn them on and see what happens.
> Additionally you will have to have an array defining SerialIO devices in
> devicetree like:
> register "SerialIoDevMode" = "{
>     [PchSerialIoIndexI2C0]  = PchSerialIoPci,
>     [PchSerialIoIndexI2C1]  = PchSerialIoPci,
>     [PchSerialIoIndexI2C2]  = PchSerialIoPci,
>     [PchSerialIoIndexI2C3]  = PchSerialIoPci,
>     [PchSerialIoIndexI2C4]  = PchSerialIoDisabled,
>     [PchSerialIoIndexI2C5]  = PchSerialIoPci,
>     [PchSerialIoIndexSPI0] = PchSerialIoPci,
>     [PchSerialIoIndexSPI1] = PchSerialIoPci,
>     [PchSerialIoIndexSPI2] = PchSerialIoDisabled,
>     [PchSerialIoIndexUART0] = PchSerialIoSkipInit,
>     [PchSerialIoIndexUART1] = PchSerialIoDisabled,
>     [PchSerialIoIndexUART2] = PchSerialIoSkipInit,
> }"
>
> So it will pass the correct parameters to FSP. You have to either choose
> PchSerialIoPci or PchSerialIoAcpi, depending on your needs.

I would also recommend checking if the PCH GPIO configuration values are
correct. In src/mainboard/vendor/model there should be a file called either
'gpio.c' or 'gpio.h', which is used to configure the function of GPIO pins.

To use the UART function, the relevant pins (balls, rather) should be
configured as "Native" function. GPIO ball numbers and functions can be
found in the PCH datasheet.
> Regards,
> Michał
>
> Best regards,

Angel Pons
>