[coreboot] core boot & ehci debug

[Scott Duplichan]

________________________________________
From: coreboot-bounces+scott=notabs.org at coreboot.org [mailto:coreboot-bounces+scott=notabs.org at coreboot.org] On Behalf Of
trevor.davenport at gmail.com
Sent: Wednesday, January 26, 2011 07:57 PM
To: coreboot at coreboot.org
Subject: [coreboot] core boot & ehci debug

Hi,

I've been trying to get coreboot to work a machine i have (http://www.coreboot.org/pipermail/coreboot/2010-November/061987.html) but
have so far have not had any luck.  I've tried most board types that are similar but all result in the same scenario, flash the rom,
reboot....nothing on screen.

This system does not have serial port available (the closest thing on the board appears to be solder contacts labeled COMB).  The
southbridge is a SB700.  Is the EHCI Debug Port support usuable on these (the wiki says WIP but it seems the code is there) and do
you think it would help to go this route?  

Is there anything else you could suggest in helping me make any progress on this board? 

Cheers,
Trevor Davenport

------------------ 

Video comes very late in the sequence of events so watching for video is not a good way to debug. Hopefully someone can answer your
EHCI debug port question. I would try to get the serial port going. If a volt meter shows that any of the pads are at a negative
level, then you have RS-232 levels and only need to figure out which is tx and rx. If there is only positive, then the pads probably
lead directly to the ITE SIO. If that were the case, you would have to somehow invert tx & rx. Boot with minimal memory. Make sure
you have included a video option rom. You could probably sanity check your coreboot image by downloading simnow. It includes a model
'shiner_family10h.bsd', which is RS780/SB700, DDR2, ITE SIO board. There is more simnow info at coreboot.org.

Thanks,
Scott