[coreboot] Broadwell IGD (on Auron_Paine)

[Stefan Reinauer]

* Georg Wicherski <gw at oxff.net> [151019 17:39]:
> Hi,
> 
> thanks to Marc Jones' SGD patch for the Auron board
> (f3214d02482a4104d7276f06d6b326b2a54c4262), I was able to get my
> Auron_Paine up to ramstage.
> 
> Unfortunately, the IGD code in soc/intel/broadwell/ appears to be
> somewhat broken. Based off Aaron's guidance on IRC, I've pin-pointed the
> issue to be within igd_setup_panel . The first gtt_read there seems to
> hang already (BIOS_SPEW log attached). Find my current code with those
> debug prints at <http://review.coreboot.org/#/c/11907/2>. FWIW, I've
> tested with some commenting-out, etc. that it's any gtt_read that
> immediately causes a hang there. Also dumped the gtt_res, small excerpt
> from the log:
> 
> --8<--
> igd's gtt_res = { base=e0000000, size=1000000, limit=e0ffffff,
> flags=60000201 }
> igd_init: waited for pre-graphics delay to pass
> igd_init: went through early init
> igd_init: RP1 graphics frequency is set
> gtt_read(PCH_PORT_HOTPLUG)
> --8<--
> 
> People on IRC mentioned that this is an issue that people may have run
> into before on Broadwell, any suggestions on how to fix the hang there?
> 
> 
> Thanks,
> G

Hi Georg,

it seems that the refcode binary was not running. Can you verify that
it was part of the image and gets executed?

Stefan