drm/i915: Split pipe+output CSC programming to noarm+arm pair
Move most of the pipe+output CSC programming to the
.color_commit_noarm() hook which runs before vblank evasion.
Only PIPE_CSC_MODE (the arming register) needs to remain in
inside the critical section.
A test case that just updates the CTM in a loop produces
the following i915_update_info numbers on ilk (w/o lockdep):
old new
Updates: 10012 Updates: 10008
| |
1us |** 1us |**********
|************* |*************
4us |********* 4us |*
|* |**
16us | 16us |
| |
66us | 66us |
| |
262us | 262us |
| |
1ms | 1ms |
| |
4ms | 4ms |
| |
17ms | 17ms |
| |
Min update: 1345ns Min update: 1268ns
Max update: 16672ns Max update: 15656ns
Average update: 3914ns Average update: 2185ns
Overruns > 100us: 0 Overruns > 100us: 0
And here is tgl (forced to update both pipe CSC and
output CSC, and with lockdep enabled):
old new
Updates: 10012 Updates: 10012
| |
1us | 1us |
| |
4us |* 4us |**
|** |**********
16us |************* 16us |*************
|* |
66us | 66us |
| |
262us | 262us |
| |
1ms | 1ms |
| |
4ms | 4ms |
| |
17ms | 17ms |
| |
Min update: 5204ns Min update: 5176ns
Max update: 176038ns Max update: 186685ns
Average update: 23931ns Average update: 16654ns
Overruns > 250us: 0 Overruns > 250us: 0
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220224165103.15682-5-ville.syrjala@linux.intel.com
Reviewed-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>