Hi,

On 21 January 2015 at 21:52, Simon Glass <[email protected]> wrote:
> Hi Maurice,
>
> On 21 January 2015 at 13:18, Simon Glass <[email protected]> wrote:
>> Hi Maurine,
>>
>> On 20 January 2015 at 18:02, Ma, Maurice <[email protected]> wrote:
>>> Hi, Simon,
>>>
>>> Just want to make sure that you are talking about the MinnowBoard 
>>> (TunnelCreek + TopCliff), not MinnowBoard Max (Baytrail), right?
>>>
>>> For MinnowBoard Max,  I have tested and the early serial port does work 
>>> before the FSP API call.
>>>
>>> For MinnowBoard, the serial port is from UART0 on TopCliff(EG20T).   In 
>>> order to enable early console in coreboot,
>>> you need to initialize the TopCliff UART 0 and then call console_init() in 
>>> romstage  after FSP TempRamInit() and before FspInit().
>>>
>>> The standard linux UART driver for EG20T is open,   you can refer to :
>>> http://lxr.free-electrons.com/source/drivers/tty/serial/pch_uart.c
>>>
>>> You just need to implement the standard RX and TX function for Coreboot.   
>>> It should be straight forward.
>>> Please note, since the EG20T UART is on PCI bus and the PCI bus is not 
>>> enumerated yet at early boot stage.   So you need to assign temporary bus 
>>> and PCI MMIO resource to the bridges and the UART controller before 
>>> accessing the UART registers.
>>
>> Yes i it Minnowboard Max. It sounds like you are saying I should get
>> serial output early in romstage, but I don't. Do I need to enable
>> something?
>
> Just to follow up, I got this working. It seems there is quite a long
> list of init to be done to get the serial working. But I have early
> output running now. Thanks for your help.

OK, one more follow-up. I'd like to get U-Boot running now if I can.

The FSP is hanging in FspInitEntry. Is there a way to turn on serial
debug to see what is going on? Is there any other debug method
available? I can't see post codes on this board and it doesn't seem to
return an error code.

I see some fields called 'SerialDebugPortAddress' in some FSPs, but
not in the header files for gold v3.

Regards,
Simon
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