Re: [PATCH 06/36] drm/amd/display: add CRTC driver-specific property for gamma TF

[Sebastian Wick <sebastian.wick@redhat.com>]

On Tue, Jun 6, 2023 at 6:19 PM Joshua Ashton <joshua@froggi.es> wrote:
>
>
>
> On 6/1/23 20:17, Harry Wentland wrote:
> >
> >
> > On 5/23/23 18:14, Melissa Wen wrote:
> >> Hook up driver-specific atomic operations for managing AMD color
> >> properties and create AMD driver-specific color management properties
> >> and attach them according to HW capabilities defined by `struct
> >> dc_color_caps`. Add enumerated transfer function property to DRM CRTC
> >> gamma to convert to wire encoding with or without a user gamma LUT.
> >> Enumerated TFs are not supported yet by the DRM color pipeline,
> >> therefore, create a DRM enum list with the predefined TFs supported by
> >> the AMD display driver.
> >>
> >> Co-developed-by: Joshua Ashton <joshua@froggi.es>
> >> Signed-off-by: Joshua Ashton <joshua@froggi.es>
> >> Signed-off-by: Melissa Wen <mwen@igalia.com>
> >> ---
> >>   drivers/gpu/drm/amd/amdgpu/amdgpu_display.c   | 36 ++++++++++
> >>   drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h      |  8 +++
> >>   .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h | 22 ++++++
> >>   .../amd/display/amdgpu_dm/amdgpu_dm_crtc.c    | 72 ++++++++++++++++++-
> >>   4 files changed, 137 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
> >> index 389396eac222..88af075e6c18 100644
> >> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
> >> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
> >> @@ -1247,6 +1247,38 @@ amdgpu_display_user_framebuffer_create(struct drm_device *dev,
> >>      return &amdgpu_fb->base;
> >>   }
> >>
> >> +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" },
> >> +};
> >
> > Let's not use the DRM_/drm_ prefix here. It might clash later when
> > we introduce DRM_ core interfaces for enumerated transfer functions.
> >
> > We'll want to specify whether something is an EOTF or an inverse EOTF,
> > or possibly an OETF. Of course that wouldn't apply to "Linear" or
> > "Unity" (I'm assuming the two are the same?).
> >
> > EOTF = electro-optical transfer function
> > This is the transfer function to go from the encoded value to an
> > optical (linear) value.
> >
> > Inverse EOTF = simply the inverse of the EOTF
> > This is usually intended to go from an optical/linear space (which
> > might have been used for blending) back to the encoded values.
> >
> > OETF = opto-electronic transfer function
> > This is usually used for converting optical signals into encoded
> > values. Usually that's done on the camera side but I think HLG might
> > define the OETF instead of the EOTF. A bit fuzzy on that. If you're
> > unclear about HLG I recommend we don't include it yet.
> >
> > It would also be good to document a bit more what each of the TFs
> > mean, but I'm fine if that comes later with a "driver-agnostic"
> > API. The key thing to clarify is whether we have an EOTF or inv_EOTF,
> > i.e. whether we use the TF to go from encoded to optical or vice
> > versa.
>
> Whether we use the inverse or not is just determined per-block though.
>
> I think we should definitely document it per-block very explicitly
> (whether it is EOTF or inv EOTF) but I don't think we need to touch the
> enums here.

Either the drm prefix has to be removed or the enum variant names have
to be explicitly be the EOTF, OETF, inverse EOTF or inverse OETF.

> - Joshie 🐸✨
>
> >
> > I know DC is sloppy and doesn't define those but it will still use
> > them as either EOTF or inv_EOTF, based on which block they're being
> > programmed, if I'm not mistaken.
> >
> >> +
> >> +#ifdef AMD_PRIVATE_COLOR
> >> +static int
> >> +amdgpu_display_create_color_properties(struct amdgpu_device *adev)
> >> +{
> >> +    struct drm_property *prop;
> >> +
> >> +    prop = drm_property_create_enum(adev_to_drm(adev),
> >> +                                    DRM_MODE_PROP_ENUM,
> >> +                                    "AMD_REGAMMA_TF",
> >> +                                    drm_transfer_function_enum_list,
> >> +                                    ARRAY_SIZE(drm_transfer_function_enum_list));
> >> +    if (!prop)
> >> +            return -ENOMEM;
> >> +    adev->mode_info.regamma_tf_property = prop;
> >> +
> >> +    return 0;
> >> +}
> >> +#endif
> >> +
> >
> > It'd be nice if we have this function and the above enum_list
> > in amdgpu_dm, possibly in amdgpu_dm_color.c. You could call it
> > directly after the amdgpu_display_modeset_create_prop() call in
> > amdgpu_dm_mode_config_init().
> >
> >>   const struct drm_mode_config_funcs amdgpu_mode_funcs = {
> >>      .fb_create = amdgpu_display_user_framebuffer_create,
> >>   };
> >> @@ -1323,6 +1355,10 @@ int amdgpu_display_modeset_create_props(struct amdgpu_device *adev)
> >>                      return -ENOMEM;
> >>      }
> >>
> >> +#ifdef AMD_PRIVATE_COLOR
> >> +    if (amdgpu_display_create_color_properties(adev))
> >> +            return -ENOMEM;
> >> +#endif
> >>      return 0;
> >>   }
> >>
> >> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h
> >> index b8633df418d4..881446c51b36 100644
> >> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h
> >> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h
> >> @@ -344,6 +344,14 @@ struct amdgpu_mode_info {
> >>      int                     disp_priority;
> >>      const struct amdgpu_display_funcs *funcs;
> >>      const enum drm_plane_type *plane_type;
> >> +
> >> +    /* Driver-private color mgmt props */
> >> +
> >> +    /* @regamma_tf_property: Transfer function for CRTC regamma
> >> +     * (post-blending). Possible values are defined by `enum
> >> +     * drm_transfer_function`.
> >> +     */
> >> +    struct drm_property *regamma_tf_property;
> >>   };
> >>
> >>   #define AMDGPU_MAX_BL_LEVEL 0xFF
> >> 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 2e2413fd73a4..ad5ee28b83dc 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 +699,20 @@ static inline void amdgpu_dm_set_mst_status(uint8_t *status,
> >>
> >>   extern const struct amdgpu_ip_block_version dm_ip_block;
> >>
> >> +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,
> >> +};
> >> +
> >>   struct dm_plane_state {
> >>      struct drm_plane_state base;
> >>      struct dc_plane_state *dc_state;
> >> @@ -726,6 +740,14 @@ struct dm_crtc_state {
> >>      struct dc_info_packet vrr_infopacket;
> >>
> >>      int abm_level;
> >> +
> >> +        /**
> >> +     * @regamma_tf:
> >> +     *
> >> +     * Pre-defined transfer function for converting internal FB -> wire
> >> +     * encoding.
> >> +     */
> >> +    enum drm_transfer_function regamma_tf;
> >
> > Again, let's avoid a drm_ prefix. Maybe name all this amdgpu_ instead.
> >
> >>   };
> >>
> >>   #define to_dm_crtc_state(x) container_of(x, struct dm_crtc_state, base)
> >> 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 e3762e806617..1eb279d341c5 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
> >> @@ -229,7 +229,6 @@ static void dm_crtc_destroy_state(struct drm_crtc *crtc,
> >>      if (cur->stream)
> >>              dc_stream_release(cur->stream);
> >>
> >> -
> >
> > nit: stray newline
> >
> > Harry
> >
> >>      __drm_atomic_helper_crtc_destroy_state(state);
> >>
> >>
> >> @@ -263,6 +262,7 @@ static struct drm_crtc_state *dm_crtc_duplicate_state(struct drm_crtc *crtc)
> >>      state->freesync_config = cur->freesync_config;
> >>      state->cm_has_degamma = cur->cm_has_degamma;
> >>      state->cm_is_degamma_srgb = cur->cm_is_degamma_srgb;
> >> +    state->regamma_tf = cur->regamma_tf;
> >>      state->crc_skip_count = cur->crc_skip_count;
> >>      state->mpo_requested = cur->mpo_requested;
> >>      /* TODO Duplicate dc_stream after objects are stream object is flattened */
> >> @@ -299,6 +299,69 @@ static int amdgpu_dm_crtc_late_register(struct drm_crtc *crtc)
> >>   }
> >>   #endif
> >>
> >> +#ifdef AMD_PRIVATE_COLOR
> >> +/**
> >> + * drm_crtc_additional_color_mgmt - enable additional color properties
> >> + * @crtc: DRM CRTC
> >> + *
> >> + * This function lets the driver enable the 3D LUT color correction property
> >> + * on a CRTC. This includes shaper LUT, 3D LUT and regamma TF. The shaper
> >> + * LUT and 3D LUT property is only attached if its size is not 0.
> >> + */
> >> +static void
> >> +dm_crtc_additional_color_mgmt(struct drm_crtc *crtc)
> >> +{
> >> +    struct amdgpu_device *adev = drm_to_adev(crtc->dev);
> >> +
> >> +    if(adev->dm.dc->caps.color.mpc.ogam_ram)
> >> +            drm_object_attach_property(&crtc->base,
> >> +                                       adev->mode_info.regamma_tf_property,
> >> +                                       DRM_TRANSFER_FUNCTION_DEFAULT);
> >> +}
> >> +
> >> +static int
> >> +amdgpu_dm_atomic_crtc_set_property(struct drm_crtc *crtc,
> >> +                               struct drm_crtc_state *state,
> >> +                               struct drm_property *property,
> >> +                               uint64_t val)
> >> +{
> >> +    struct amdgpu_device *adev = drm_to_adev(crtc->dev);
> >> +    struct dm_crtc_state *acrtc_state = to_dm_crtc_state(state);
> >> +
> >> +    if (property == adev->mode_info.regamma_tf_property) {
> >> +            if (acrtc_state->regamma_tf != val) {
> >> +                    acrtc_state->regamma_tf = val;
> >> +                    acrtc_state->base.color_mgmt_changed |= 1;
> >> +            }
> >> +    } else {
> >> +            drm_dbg_atomic(crtc->dev,
> >> +                           "[CRTC:%d:%s] unknown property [PROP:%d:%s]]\n",
> >> +                           crtc->base.id, crtc->name,
> >> +                           property->base.id, property->name);
> >> +            return -EINVAL;
> >> +    }
> >> +
> >> +    return 0;
> >> +}
> >> +
> >> +static int
> >> +amdgpu_dm_atomic_crtc_get_property(struct drm_crtc *crtc,
> >> +                               const struct drm_crtc_state *state,
> >> +                               struct drm_property *property,
> >> +                               uint64_t *val)
> >> +{
> >> +    struct amdgpu_device *adev = drm_to_adev(crtc->dev);
> >> +    struct dm_crtc_state *acrtc_state = to_dm_crtc_state(state);
> >> +
> >> +    if (property == adev->mode_info.regamma_tf_property)
> >> +            *val = acrtc_state->regamma_tf;
> >> +    else
> >> +            return -EINVAL;
> >> +
> >> +    return 0;
> >> +}
> >> +#endif
> >> +
> >>   /* Implemented only the options currently available for the driver */
> >>   static const struct drm_crtc_funcs amdgpu_dm_crtc_funcs = {
> >>      .reset = dm_crtc_reset_state,
> >> @@ -317,6 +380,10 @@ static const struct drm_crtc_funcs amdgpu_dm_crtc_funcs = {
> >>   #if defined(CONFIG_DEBUG_FS)
> >>      .late_register = amdgpu_dm_crtc_late_register,
> >>   #endif
> >> +#ifdef AMD_PRIVATE_COLOR
> >> +    .atomic_set_property = amdgpu_dm_atomic_crtc_set_property,
> >> +    .atomic_get_property = amdgpu_dm_atomic_crtc_get_property,
> >> +#endif
> >>   };
> >>
> >>   static void dm_crtc_helper_disable(struct drm_crtc *crtc)
> >> @@ -480,6 +547,9 @@ int amdgpu_dm_crtc_init(struct amdgpu_display_manager *dm,
> >>
> >>      drm_mode_crtc_set_gamma_size(&acrtc->base, MAX_COLOR_LEGACY_LUT_ENTRIES);
> >>
> >> +#ifdef AMD_PRIVATE_COLOR
> >> +    dm_crtc_additional_color_mgmt(&acrtc->base);
> >> +#endif
> >>      return 0;
> >>
> >>   fail:
> >
>