Re: rtsx_pci not restoring ASPM state after suspend/resume

From: James Ettle
Date: Sat Jul 25 2020 - 16:27:50 EST


On Fri, 2020-07-24 at 18:13 -0500, Bjorn Helgaas wrote:
>
> Maybe we should simplify this a little bit more. James, if you don't
> touch ASPM config at all, either manually or via udev, does the ASPM
> configuration stay the same across suspend/resume?
>

Yes, it stays the same. Explicitly:

With the udev rule disabled, immediately following clean boot from
power-off (and no additional tinkering), ASPM is OFF to the best of my
knowledge:

- link/l1_aspm in sysfs is 0 for PCI devices 0000:01:00.[01];
- the processor sleeps no deeper than package C3.

The situation above is the same following a suspend/resume cycle --
both in terms of sysfs, and observed package C-state occupancy.

[Tested on kernel 5.7.10, but the behaviour is the same as prior
kernels.]

Thanks,
James.