Linux 6.12 Introducing DRM "Power Saving Policy" For Better Desktop Integration

Sent out today was the first batch of drm-misc-next patches of Direct Rendering Manager updates that will be targeting the Linux 6.12 kernel later in the year. Notable from this pull is introducing a new DRM Power Saving Policy for display connectors and is initially wired up for the AMDGPU kernel graphics driver.

This new "Power Saving Policy" for monitor/display connectors is intended to be common across drivers and for communicating between display compositors (desktops) and drivers whether power saving features should be used that could compromise the experience intended by the desktop compositor.

The Power Saving Policy for the connector currently can indicate whether the driver should require color accuracy and in turn for the driver/hardware to disable power saving features that could affect color fidelity. Another policy option is for requiring low-latency to disable power saving features that affect the display latency like Panel Self Refresh (PSR).

This was worked on in collaboration with KDE and other desktops for ensuring the wishes of the compositor are expressed to the graphics driver. Initially this is wired up for the AMDGPU driver as the common DRM property code was worked on by AMD. With time other DRM drivers will likely be supporting this Power Saving Policy property on connectors. There is a KDE KWin merge request for making use of this property on the compositor side.

Today's drm-misc-next pull request also adds dynamic per-CRTC vblank configuration support to the modesetting code, TTM improvements, improved BMC handling for the MGAG200 driver, cleanups for the nouveau driver, and other small driver changes.

Update (9 August): Linux's DRM Power Saving Policy Gets Reverted For Now