[Resending after accidentally replying off-list]
On 2015-11-12 14:32, Nico Huber wrote:
On 12.11.2015 04:37, Patrick 'P. J.' McDermott wrote:
On 2015-11-11 16:50, Nico Huber wrote:
On 11.11.2015 00:49, Patrick 'P. J.' McDermott wrote:
I've been looking into S3 resume on GM45 mainboards, which often fails in rather interesting ways.
Well, the S3 support wasn't really tested during GM45 development. Maybe it's just plainly broken. My development system at work (roda/rk9) doesn't resume because of another problem (but didn't fail raminit on the resume path in 3 of 3 tries). So it will need some work before I can test this.
Ah, OK. What kind of other problem? In addition to the raminit reset, I've seen resume fail by an SMM hang and in other ways.
There was a minor flaw in the mainboard code: http://review.coreboot.org/#/q/topic:rk9-resume
Ah, I see. Yeah, X200 and T400 romstages don't have that flaw.
With patches applied, it works halfway reliable: about 30 good suspend- resume cycles before it fails. Only eye-catching thing in dmesg was a warning about the backlight being already enabled. I haven't yet a serial log for a failed resume.
How does it fail?
One more thing that came in mind: The reset after a failed receive- enable calibration is kind of wanted. IIRC, we left the watchdog enable for a case of failing raminit. But I don't remember what the exact fai- lure was. It wasn't very unlikely to occur (> 1/1000). If we run into this on the resume path too, it might never work reliable :-/