-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256
On 12/10/2018 01:55 PM, Angel Pons wrote:
Hello,
On Mon, Dec 10, 2018, 19:45 Taiidan@gmx.com mailto:Taiidan@gmx.com <Taiidan@gmx.com mailto:Taiidan@gmx.com wrote:
S3 - it does work but you just have to wait a long time I would guess that maybe there is some ram re-training going on and that is why resuming from S3 takes over a minute.AFAIK, retraining the RAM destroys its contents (and that is why timings must be cached to flash for S3 to work). Does AMD have anything special to retrain memory yet still preserve RAM data to allow suspend, or am I missing something here?
Best regards,
Angel Pons
You are correct. The memory is not (and cannot be) retrained, the previous settings are loaded from the s3nv region of Flash (this is also why the settings change on each boot -- the last known good training data is loaded into Flash to support resume from suspend).
My understanding is that because the current coreboot native AMD codebase doesn't support relocatable ramstage (yet?) we're hitting a slow path somewhere in resume. I think there was some work being put into adding the relocateable ramstage support but I don't know current status.
- -- Timothy Pearson Raptor Engineering +1 (415) 727-8645 (direct line) +1 (512) 690-0200 (switchboard) https://www.raptorengineering.com