drm: Check whether the gamma lut has changed before updating

drm_crtc_legacy_gamma_set updates the gamma_lut blob unconditionally,
which leads to unnecessary reprogramming of hardware.

Check whether the blob contents has actually changed before
signalling that it has been updated.

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
This commit is contained in:
Dave Stevenson
2021-11-02 16:01:36 +00:00
committed by Dom Cobley
parent 6f828ffc3e
commit f651114aa9

View File

@@ -332,7 +332,9 @@ static int drm_crtc_legacy_gamma_set(struct drm_crtc *crtc,
replaced = drm_property_replace_blob(&crtc_state->degamma_lut, replaced = drm_property_replace_blob(&crtc_state->degamma_lut,
use_gamma_lut ? NULL : blob); use_gamma_lut ? NULL : blob);
replaced |= drm_property_replace_blob(&crtc_state->ctm, NULL); replaced |= drm_property_replace_blob(&crtc_state->ctm, NULL);
replaced |= drm_property_replace_blob(&crtc_state->gamma_lut, if (!crtc_state->gamma_lut || !crtc_state->gamma_lut->data ||
memcmp(crtc_state->gamma_lut->data, blob_data, blob->length))
replaced |= drm_property_replace_blob(&crtc_state->gamma_lut,
use_gamma_lut ? blob : NULL); use_gamma_lut ? blob : NULL);
crtc_state->color_mgmt_changed |= replaced; crtc_state->color_mgmt_changed |= replaced;