[coreboot] Does S3 work on Haswell boards?

[Nico Huber]

Hi Aladyshev,

On 30.10.2017 16:49, Аладышев Константин wrote:
> I have problem with S3 mode on Haswell board. Everything is fine if S3 time
> is very small (<15 seconds), but if it is longer, coreboot won't resume. It
> fails on quick_ram_check.

sounds much like the DRAM loses some state. e.g. if the MRC doesn't
reinitialize MRx registers in the DRAM and their state is lost,
quick_ram_check() could fail even if the controller is configured
correctly.

There was a DRAM_RESET_GATE_GPIO Kconfig for Sandy/Ivy Bridge but no
equivalent for Haswell. Maybe your board needs something like that?

Or maybe even power was lost for the DRAM. It all pretty much depends
on the board.

> 
> I've enabled mrc.cache and ME in coreboot. I use ME binary from original
> board and MRC.bin from Google Panther.
> 
> ...
> 
> It seems like DRAM controller and ME are initialized correctly (like in
> normal boot), what can be wrong?
> 
> Does S3 work on Haswell boards?

It definitely worked at some point. Matt might know a latest revision
where it was tested on Chromebooks or maybe can verify if it still works
upstream.

Nico