Re: [RFC PATCH 07/40] drm/amd/display: add CRTC gamma TF to driver-private props

From: Joshua Ashton
Date: Tue May 09 2023 - 12:55:41 EST


I am okay with us dropping the shaper + 3D LUT from crtc. It has
problems anyway wrt. atomicity.

On Tue, 9 May 2023 at 16:34, Melissa Wen <mwen@xxxxxxxxxx> wrote:
>
> On 05/08, Harry Wentland wrote:
> >
> >
> > On 4/23/23 10:10, Melissa Wen wrote:
> > > From: Joshua Ashton <joshua@xxxxxxxxx>
> > >
> > > Add predefined transfer function property to DRM CRTC gamma to convert
> > > to wire encoding with or without gamma LUT.
> > >
> >
> > Are all these new CRTC properties used by gamescope? I would be reluctant
> > to merge them if they're currently not needed.
>
> The regamma TF yes. The shaper and 3D LUT not yet.
>
> I'll double check with Joshie and drop from the series what we don't
> have a short-term perspective of usage.
>
> >
> > > Co-developed-by: Melissa Wen <mwen@xxxxxxxxxx>
> > > Signed-off-by: Melissa Wen <mwen@xxxxxxxxxx>
> > > Signed-off-by: Joshua Ashton <joshua@xxxxxxxxx>
> > > ---
> > > drivers/gpu/drm/amd/amdgpu/amdgpu_display.c | 22 ++++++++++++++++++
> > > drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h | 4 ++++
> > > .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h | 23 +++++++++++++++++++
> > > .../amd/display/amdgpu_dm/amdgpu_dm_crtc.c | 13 +++++++++++
> > > 4 files changed, 62 insertions(+)
> > >
> > > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
> > > index 2abe5fe87c10..1913903cab88 100644
> > > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
> > > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
> > > @@ -1248,6 +1248,19 @@ amdgpu_display_user_framebuffer_create(struct drm_device *dev,
> > > }
> > >
> > > #ifdef CONFIG_STEAM_DECK
> > > +static const struct drm_prop_enum_list drm_transfer_function_enum_list[] = {
> > > + { DRM_TRANSFER_FUNCTION_DEFAULT, "Default" },
> > > + { DRM_TRANSFER_FUNCTION_SRGB, "sRGB" },
> > > + { DRM_TRANSFER_FUNCTION_BT709, "BT.709" },
> > > + { DRM_TRANSFER_FUNCTION_PQ, "PQ (Perceptual Quantizer)" },
> > > + { DRM_TRANSFER_FUNCTION_LINEAR, "Linear" },
> > > + { DRM_TRANSFER_FUNCTION_UNITY, "Unity" },
> > > + { DRM_TRANSFER_FUNCTION_HLG, "HLG (Hybrid Log Gamma)" },
> > > + { DRM_TRANSFER_FUNCTION_GAMMA22, "Gamma 2.2" },
> > > + { DRM_TRANSFER_FUNCTION_GAMMA24, "Gamma 2.4" },
> > > + { DRM_TRANSFER_FUNCTION_GAMMA26, "Gamma 2.6" },
> > > +};
> > > +
> >
> > Would it be better to prefix things with AMD_/amd_ to avoid confusion? On the other
> > hand, these will likely just move into DRM core once we get the generic color uAPI.
> >
> > Harry
> >
> > > static int
> > > amdgpu_display_create_color_properties(struct amdgpu_device *adev)
> > > {
> > > @@ -1281,6 +1294,15 @@ amdgpu_display_create_color_properties(struct amdgpu_device *adev)
> > > return -ENOMEM;
> > > adev->mode_info.lut3d_size_property = prop;
> > >
> > > + prop = drm_property_create_enum(adev_to_drm(adev),
> > > + DRM_MODE_PROP_ENUM,
> > > + "GAMMA_TF",
> > > + drm_transfer_function_enum_list,
> > > + ARRAY_SIZE(drm_transfer_function_enum_list));
> > > + if (!prop)
> > > + return -ENOMEM;
> > > + adev->mode_info.gamma_tf_property = prop;
> > > +
> > > return 0;
> > > }
> > > #endif
> > > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h
> > > index 205fa4f5bea7..76337e18c728 100644
> > > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h
> > > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h
> > > @@ -368,6 +368,10 @@ struct amdgpu_mode_info {
> > > * LUT as supported by the driver (read-only).
> > > */
> > > struct drm_property *lut3d_size_property;
> > > + /**
> > > + * @gamma_tf_property: Transfer function for CRTC regamma.
> > > + */
> > > + struct drm_property *gamma_tf_property;
> > > #endif
> > > };
> > >
> > > diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
> > > index 09c3e1858b56..1e90a2dd445e 100644
> > > --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
> > > +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
> > > @@ -699,6 +699,23 @@ static inline void amdgpu_dm_set_mst_status(uint8_t *status,
> > >
> > > extern const struct amdgpu_ip_block_version dm_ip_block;
> > >
> > > +#ifdef CONFIG_STEAM_DECK
> > > +enum drm_transfer_function {
> > > + DRM_TRANSFER_FUNCTION_DEFAULT,
> > > +
> > > + DRM_TRANSFER_FUNCTION_SRGB,
> > > + DRM_TRANSFER_FUNCTION_BT709,
> > > + DRM_TRANSFER_FUNCTION_PQ,
> > > + DRM_TRANSFER_FUNCTION_LINEAR,
> > > + DRM_TRANSFER_FUNCTION_UNITY,
> > > + DRM_TRANSFER_FUNCTION_HLG,
> > > + DRM_TRANSFER_FUNCTION_GAMMA22,
> > > + DRM_TRANSFER_FUNCTION_GAMMA24,
> > > + DRM_TRANSFER_FUNCTION_GAMMA26,
> > > + DRM_TRANSFER_FUNCTION_MAX,
> > > +};
> > > +#endif
> > > +
> > > struct dm_plane_state {
> > > struct drm_plane_state base;
> > > struct dc_plane_state *dc_state;
> > > @@ -751,6 +768,12 @@ struct dm_crtc_state {
> > > * &struct drm_color_lut.
> > > */
> > > struct drm_property_blob *lut3d;
> > > + /**
> > > + * @gamma_tf:
> > > + *
> > > + * Pre-defined transfer function for converting internal FB -> wire encoding.
> > > + */
> > > + enum drm_transfer_function gamma_tf;
> > > #endif
> > > };
> > >
> > > diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c
> > > index 0e1280228e6e..79324fbab1f1 100644
> > > --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c
> > > +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c
> > > @@ -272,6 +272,7 @@ static struct drm_crtc_state *dm_crtc_duplicate_state(struct drm_crtc *crtc)
> > > #ifdef CONFIG_STEAM_DECK
> > > state->shaper_lut = cur->shaper_lut;
> > > state->lut3d = cur->lut3d;
> > > + state->gamma_tf = cur->gamma_tf;
> > >
> > > if (state->shaper_lut)
> > > drm_property_blob_get(state->shaper_lut);
> > > @@ -336,6 +337,11 @@ dm_crtc_additional_color_mgmt(struct drm_crtc *crtc)
> > > adev->mode_info.lut3d_size_property,
> > > MAX_COLOR_3DLUT_ENTRIES);
> > > }
> > > +
> > > + if(adev->dm.dc->caps.color.mpc.ogam_ram)
> > > + drm_object_attach_property(&crtc->base,
> > > + adev->mode_info.gamma_tf_property,
> > > + DRM_TRANSFER_FUNCTION_DEFAULT);
> > > }
> > >
> > > static int
> > > @@ -398,6 +404,11 @@ amdgpu_dm_atomic_crtc_set_property(struct drm_crtc *crtc,
> > > &replaced);
> > > acrtc_state->base.color_mgmt_changed |= replaced;
> > > return ret;
> > > + } else if (property == adev->mode_info.gamma_tf_property) {
> > > + if (acrtc_state->gamma_tf != val) {
> > > + acrtc_state->gamma_tf = val;
> > > + acrtc_state->base.color_mgmt_changed |= 1;
> > > + }
> > > } else {
> > > drm_dbg_atomic(crtc->dev,
> > > "[CRTC:%d:%s] unknown property [PROP:%d:%s]]\n",
> > > @@ -424,6 +435,8 @@ amdgpu_dm_atomic_crtc_get_property(struct drm_crtc *crtc,
> > > else if (property == adev->mode_info.lut3d_property)
> > > *val = (acrtc_state->lut3d) ?
> > > acrtc_state->lut3d->base.id : 0;
> > > + else if (property == adev->mode_info.gamma_tf_property)
> > > + *val = acrtc_state->gamma_tf;
> > > else
> > > return -EINVAL;
> > >
> >
> >