• Jesse Barnes's avatar
    drm/i915: add dynamic clock frequency control · 652c393a
    Jesse Barnes authored
    There are several sources of unnecessary power consumption on Intel
    graphics systems. The first is the LVDS clock. TFTs don't suffer from
    persistence issues like CRTs, and so we can reduce the LVDS refresh rate
    when the screen is idle. It will be automatically upclocked when
    userspace triggers graphical activity. Beyond that, we can enable memory
    self refresh. This allows the memory to go into a lower power state when
    the graphics are idle. Finally, we can drop some clocks on the gpu
    itself. All of these things can be reenabled between frames when GPU
    activity is triggered, and so there should be no user visible graphical
    changes.
    Signed-off-by: default avatarJesse Barnes <jesse.barnes@intel.com>
    Signed-off-by: default avatarMatthew Garrett <mjg@redhat.com>
    Signed-off-by: default avatarEric Anholt <eric@anholt.net>
    652c393a
i915_suspend.c 19.2 KB