On Thu, Feb 15, 2018 at 02:45:29PM -0500, Daniele Castagna wrote: > rk3399 has the option of setting per-plane gamma. > The YUV2YUV registers are per-plane. Each plane YUV2YUV pipeline has > at least 3 optional stages, two of those being degamma and gamma, and > they can be configured per-plane. > > I'm not sure about Intel HW. I think they might have something similar > planned, considering the original patch was from uma.shankar. CCing > directly in case he knows more. IIRC some of out upcoming stuff will have a pipeline like 'csc->degamma->csc->gamma->blender'. I don't really know what the point of the post csc gamma is though. Normally you would not want to reapply any gamma prior to blending. The only use case I can think of would be if you don't have a gamma lut in the crtc for post blend gamma. In that case I suppose you might consider doing the gamma before blending and accepting the slightly incorrect blending results. But at least on our hardware we always have a gamma lut in the crtc as well. So yeah, I don't really have any reason why we'd need to actually to expose the per-plane gamma. Some "crazy" artistic use case perhaps? I'm totally fine not exposing it until someone comes up with an actual use for it. Does rk3399 have a dedicated csc for yuv->rgb before degamma? Or are you supposed to use the same csc for that as you'd use for ctm? In that case I can understand why the hw would have a gamm lut on each side of the csc. But it would also means that you can't do yuv->rgb and ctm at the same time unless you're fine with doing it wrong. > > On Thu, Feb 15, 2018 at 2:29 PM, Harry Wentland <harry.wentland@xxxxxxx> wrote: > > On 2018-02-15 12:32 AM, Daniele Castagna wrote: > >> From: "uma.shankar at intel.com (Uma Shankar)" <uma.shankar@xxxxxxxxx> > >> > >> Add plane gamma as blob property and size as a > >> range property. > >> > > > > Plane degamma & CTM make sense to me but I'm not sure why gamma would be on a per-plane basis. That said, HW sometimes has these implemented in odd ways. Do we know of any HW that will currently or in the future need per-plane gamma or are we just trying to cover all potentialities? > > > > Harry > > > >> (am from https://patchwork.kernel.org/patch/9971325/) > >> > >> Change-Id: I606cd40c9748b136fc2bf4750bea1da285add62d > >> Signed-off-by: Uma Shankar <uma.shankar at intel.com> > >> --- > >> drivers/gpu/drm/drm_atomic.c | 8 ++++++++ > >> drivers/gpu/drm/drm_atomic_helper.c | 4 ++++ > >> drivers/gpu/drm/drm_mode_config.c | 14 ++++++++++++++ > >> include/drm/drm_mode_config.h | 11 +++++++++++ > >> include/drm/drm_plane.h | 9 +++++++++ > >> 5 files changed, 46 insertions(+) > >> > >> diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c > >> index d4b8c6cc84128..f634f6450f415 100644 > >> --- a/drivers/gpu/drm/drm_atomic.c > >> +++ b/drivers/gpu/drm/drm_atomic.c > >> @@ -778,6 +778,12 @@ static int drm_atomic_plane_set_property(struct drm_plane *plane, > >> &replaced); > >> state->color_mgmt_changed |= replaced; > >> return ret; > >> + } else if (property == config->plane_gamma_lut_property) { > >> + ret = drm_atomic_replace_property_blob_from_id(dev, > >> + &state->gamma_lut, > >> + val, -1, &replaced); > >> + state->color_mgmt_changed |= replaced; > >> + return ret; > >> } else { > >> return -EINVAL; > >> } > >> @@ -841,6 +847,8 @@ drm_atomic_plane_get_property(struct drm_plane *plane, > >> state->degamma_lut->base.id : 0; > >> } else if (property == config->plane_ctm_property) { > >> *val = (state->ctm) ? state->ctm->base.id : 0; > >> + } else if (property == config->plane_gamma_lut_property) { > >> + *val = (state->gamma_lut) ? state->gamma_lut->base.id : 0; > >> } else { > >> return -EINVAL; > >> } > >> diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c > >> index 17e137a529a0e..97dbb36153d14 100644 > >> --- a/drivers/gpu/drm/drm_atomic_helper.c > >> +++ b/drivers/gpu/drm/drm_atomic_helper.c > >> @@ -3495,6 +3495,9 @@ void __drm_atomic_helper_plane_duplicate_state(struct drm_plane *plane, > >> drm_property_reference_blob(state->degamma_lut); > >> if (state->ctm) > >> drm_property_reference_blob(state->ctm); > >> + if (state->gamma_lut) > >> + drm_property_reference_blob(state->gamma_lut); > >> + > >> state->color_mgmt_changed = false; > >> } > >> EXPORT_SYMBOL(__drm_atomic_helper_plane_duplicate_state); > >> @@ -3543,6 +3546,7 @@ void __drm_atomic_helper_plane_destroy_state(struct drm_plane_state *state) > >> > >> drm_property_unreference_blob(state->degamma_lut); > >> drm_property_unreference_blob(state->ctm); > >> + drm_property_unreference_blob(state->gamma_lut); > >> } > >> EXPORT_SYMBOL(__drm_atomic_helper_plane_destroy_state); > >> > >> diff --git a/drivers/gpu/drm/drm_mode_config.c b/drivers/gpu/drm/drm_mode_config.c > >> index c8763977413e7..bc6f8e51c7464 100644 > >> --- a/drivers/gpu/drm/drm_mode_config.c > >> +++ b/drivers/gpu/drm/drm_mode_config.c > >> @@ -368,6 +368,20 @@ static int drm_mode_create_standard_properties(struct drm_device *dev) > >> return -ENOMEM; > >> dev->mode_config.plane_ctm_property = prop; > >> > >> + prop = drm_property_create(dev, > >> + DRM_MODE_PROP_BLOB, > >> + "PLANE_GAMMA_LUT", 0); > >> + if (!prop) > >> + return -ENOMEM; > >> + dev->mode_config.plane_gamma_lut_property = prop; > >> + > >> + prop = drm_property_create_range(dev, > >> + DRM_MODE_PROP_IMMUTABLE, > >> + "PLANE_GAMMA_LUT_SIZE", 0, UINT_MAX); > >> + if (!prop) > >> + return -ENOMEM; > >> + dev->mode_config.plane_gamma_lut_size_property = prop; > >> + > >> return 0; > >> } > >> > >> diff --git a/include/drm/drm_mode_config.h b/include/drm/drm_mode_config.h > >> index ad7235ced531b..3ca3eb3c98950 100644 > >> --- a/include/drm/drm_mode_config.h > >> +++ b/include/drm/drm_mode_config.h > >> @@ -740,6 +740,17 @@ struct drm_mode_config { > >> * degamma LUT. > >> */ > >> struct drm_property *plane_ctm_property; > >> + /** > >> + * @plane_gamma_lut_property: Optional Plane property to set the LUT > >> + * used to convert the colors, after the CTM matrix, to the common > >> + * gamma space chosen for blending. > >> + */ > >> + struct drm_property *plane_gamma_lut_property; > >> + /** > >> + * @plane_gamma_lut_size_property: Optional Plane property for the size > >> + * of the gamma LUT as supported by the driver (read-only). > >> + */ > >> + struct drm_property *plane_gamma_lut_size_property; > >> /** > >> * @ctm_property: Optional CRTC property to set the > >> * matrix used to convert colors after the lookup in the > >> diff --git a/include/drm/drm_plane.h b/include/drm/drm_plane.h > >> index 21aecc9c91a09..acabb85009a14 100644 > >> --- a/include/drm/drm_plane.h > >> +++ b/include/drm/drm_plane.h > >> @@ -147,6 +147,15 @@ struct drm_plane_state { > >> */ > >> struct drm_property_blob *ctm; > >> > >> + /** > >> + * @gamma_lut: > >> + * > >> + * Lookup table for converting pixel data after the color conversion > >> + * matrix @ctm. See drm_plane_enable_color_mgmt(). The blob (if not > >> + * NULL) is an array of &struct drm_color_lut. > >> + */ > >> + struct drm_property_blob *gamma_lut; > >> + > >> struct drm_atomic_state *state; > >> > >> bool color_mgmt_changed : 1; > >> > _______________________________________________ > dri-devel mailing list > dri-devel@xxxxxxxxxxxxxxxxxxxxx > https://lists.freedesktop.org/mailman/listinfo/dri-devel -- Ville Syrjälä Intel OTC _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
