[TuxOnIce-users] Graphics power profile works after suspend and resume, but not after hibernate and resume

[Nigel Cunningham]

Hi Harald.

On 02/08/11 00:09, Harald Judt wrote:
> Hi,
> 
> I've got the following very strange problem regarding hibernation and
> graphics card power profile:
> 
> * Boot system, set power profile to 'low':
>   'echo low > /sys/class/drm/card0/device/power_profile'
> 
> * Hibernate & resume:
>   power profile is still at low when checked, but
>     1) Clocks are at defaults.
>     2) Changing power profile has no effects on the clocks.
> 
> * Suspend & resume:
>     1) Power profile works as expected.
>     2) If done after hibernate & resume, it fixes the issue.
> 
> 
> Question:
> 
> Is this a problem with the driver or could there be something wrong with
> the hibernation code? There should not be any differences between
> suspend-to-ram and suspend-to-disk for the driver??
> 
> It only happens with this specific graphics card where drm/kms support
> was implemented not long ago (ATI Radeon HD6950).
> 
> BTW: This occurs when using vanilla kernel too, so this might be the
> wrong place to ask for clarification, but anyway...?

Definitely a driver issue - I don't touch driver settings, and use the
same driver model calls for saving and restoring device state that
swsusp uses.

Regards,

Nigel

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