Re: [PATCH] ACPI / sleep: EC-based wakeup from suspend-to-idle on recent systems

From: Tom Lanyon
Date: Thu Jul 06 2017 - 07:42:04 EST


Sorry for the slow response - I've just had a chance to run some more tests.

I tried to disable the SD card reader in the BIOS as suggested earlier
in the thread, but that didn't seem to make a significant change.
More inline below.

On Tue, 2017-06-27 at 17:03 +0200, Rafael J. Wysocki wrote:
> I would carry out s2idle under turbostat to see how much PC10
> residency is there while suspended. That may be a significant factor.
>
> Most likely there is a device preventing the SoC from reaching its
> deepest low-power states under Linux on your system and it needs to be
> identified and dealt with.

I'm not entirely sure how turbostat records metrics so wasn't sure how
to measure correctly. I kept turbostat running while performing a
s2idle and recorded the output:

https://gist.githubusercontent.com/tomlanyon/3238e742a155e7fa27658aa0960bdee4/raw/98b5f050e5eb2f88af47b2afd17080e7dd85d20f/turbostat

I'm not familiar with the output format - I see some high percentages
of C10, but nothing in Pkg%pc10. Which is of interest in this
scenario?

On 28 June 2017 at 02:14, Srinivas Pandruvada
<srinivas.pandruvada@xxxxxxxxxxxxxxx> wrote:
> Also make sure that you have no FW loading error for i915.
> #dmesg | grep i915
> It will display that Guc FW was loaded etc..
> The latest FW can be downloaded from
> https://01.org/linuxgraphics/downloads/firmware
>
> If you don't see PC10 residency, we can try something more.

I've confirmed that there's no FW errors for the i915.