On Tue, Sep 18, 2018 at 11:11:15AM -0700, Radhakrishna Sripada wrote:
> Use the newly added "max bpc" connector property to limit pipe bpp.
>
> V3: Use drm_connector_state to access the "max bpc" property
> V4: Initialize the drm property, add suuport to DP(Ville)
> V5: Use the property in the connector and fix CI failure(Ville)
> V6: Use the core function to attach max_bpc property, remove the redundant
> clamping of pipe bpp based on connector info
> V7: Fix Checkpatch warnings
>
> Cc: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
> Cc: Daniel Vetter <daniel.vetter@xxxxxxxx>
> Cc: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx>
> Cc: Kishore Kadiyala <kishore.kadiyala@xxxxxxxxx>
> Cc: Manasi Navare <manasi.d.navare@xxxxxxxxx>
> Cc: Stanislav Lisovskiy <stanislav.lisovskiy@xxxxxxxxx>
> Signed-off-by: Radhakrishna Sripada <radhakrishna.sripada@xxxxxxxxx>
> ---
> drivers/gpu/drm/i915/intel_display.c | 49 ++++++++++++++++++++----------------
> drivers/gpu/drm/i915/intel_dp.c | 5 ++++
> drivers/gpu/drm/i915/intel_hdmi.c | 5 ++++
> 3 files changed, 38 insertions(+), 21 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index eb25037d7b38..75afd53590b1 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -10845,29 +10845,37 @@ static void intel_modeset_update_connector_atomic_state(struct drm_device *dev)
> }
>
> static void
> -connected_sink_compute_bpp(struct intel_connector *connector,
> - struct intel_crtc_state *pipe_config)
> +connected_sink_max_bpp(struct drm_connector_state *conn_state,
> + struct intel_crtc_state *pipe_config)
> {
> - const struct drm_display_info *info = &connector->base.display_info;
> - int bpp = pipe_config->pipe_bpp;
> -
> - DRM_DEBUG_KMS("[CONNECTOR:%d:%s] checking for sink bpp constrains\n",
> - connector->base.base.id,
> - connector->base.name);
> -
> - /* Don't use an invalid EDID bpc value */
> - if (info->bpc != 0 && info->bpc * 3 < bpp) {
> - DRM_DEBUG_KMS("clamping display bpp (was %d) to EDID reported max of %d\n",
> - bpp, info->bpc * 3);
> - pipe_config->pipe_bpp = info->bpc * 3;
> + if (pipe_config->pipe_bpp < conn_state->max_bpc * 3) {
> + conn_state->max_bpc = pipe_config->pipe_bpp / 3;
> + return;
This back and forth between max_bpc and pipe_bpp is a bit confusing.
I'd probably leave max_bpc alone here and just update pipe_bpp as
needed.
> }
>
> - /* Clamp bpp to 8 on screens without EDID 1.4 */
> - if (info->bpc == 0 && bpp > 24) {
> - DRM_DEBUG_KMS("clamping display bpp (was %d) to default limit of 24\n",
> - bpp);
> - pipe_config->pipe_bpp = 24;
> + switch (conn_state->max_bpc) {
This is missing the 6bpc case at least. I suppose the current code
isn't particuraly robust against unexpected values coming via
info->bpc. The switch statement does seem an improvement in that
regard. Though would be nice to compact it a bit using eg. the gcc
case range extension.
> + case 8:
> + case 9:
> + pipe_config->pipe_bpp = 8 * 3;
> + break;
> + case 10:
> + case 11:
> + pipe_config->pipe_bpp = 10 * 3;
> + break;
> + case 12:
> + case 13:
> + case 14:
> + case 15:
With the proposed min() we'd never get bpc > 12 here.
> + pipe_config->pipe_bpp = 12 * 3;
> + break;
> + case 16:
> + pipe_config->pipe_bpp = 16 * 3;
> + break;
> + default:
> + break;
Maybe just return an error here. I suppose it should never happen unless
there's some bogus displays out there that report < 6 bpc.
> }
> +
> + DRM_DEBUG_KMS("Limiting display bpp to %d\n", pipe_config->pipe_bpp);
Would be nice to include all the relevant information in this debug
print: original pipe_bpp, info->bpc*3, max_requested_bpc.
Maybe something like this would work to keep the code easy to read:
{
bpp = min(pipe_bpp, max_bpc*3);
switch (bpp) {
...
}
if (bpp != pipe_bpp) {
DRM_DEBUG_KMS(...);
pipe_bpp = bpp;
}
}
> }
>
> static int
> @@ -10898,8 +10906,7 @@ compute_baseline_pipe_bpp(struct intel_crtc *crtc,
> if (connector_state->crtc != &crtc->base)
> continue;
>
> - connected_sink_compute_bpp(to_intel_connector(connector),
> - pipe_config);
> + connected_sink_max_bpp(connector_state, pipe_config);
> }
>
> return bpp;
> diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
> index 436c22de33b6..aefca1d9e87b 100644
> --- a/drivers/gpu/drm/i915/intel_dp.c
> +++ b/drivers/gpu/drm/i915/intel_dp.c
> @@ -5719,6 +5719,11 @@ intel_dp_add_properties(struct intel_dp *intel_dp, struct drm_connector *connect
> intel_attach_force_audio_property(connector);
>
> intel_attach_broadcast_rgb_property(connector);
> + if ((IS_G4X(dev_priv) || IS_VALLEYVIEW(dev_priv) ||
> + IS_CHERRYVIEW(dev_priv)))
Just HAS_GMCH_DISPLAY() will do here.
> + drm_connector_attach_max_bpc_property(connector, 8, 10);
> + else if (INTEL_GEN(dev_priv) >= 5)
> + drm_connector_attach_max_bpc_property(connector, 8, 12);
DP does support 6 bpc as well, so we may want to reduce the min to 6
here.
>
> if (intel_dp_is_edp(intel_dp)) {
> u32 allowed_scalers;
> diff --git a/drivers/gpu/drm/i915/intel_hdmi.c b/drivers/gpu/drm/i915/intel_hdmi.c
> index a2dab0b6bde6..2b432c7e4f8a 100644
> --- a/drivers/gpu/drm/i915/intel_hdmi.c
> +++ b/drivers/gpu/drm/i915/intel_hdmi.c
> @@ -2109,11 +2109,16 @@ static const struct drm_encoder_funcs intel_hdmi_enc_funcs = {
> static void
> intel_hdmi_add_properties(struct intel_hdmi *intel_hdmi, struct drm_connector *connector)
> {
> + struct drm_i915_private *dev_priv = to_i915(connector->dev);
> +
> intel_attach_force_audio_property(connector);
> intel_attach_broadcast_rgb_property(connector);
> intel_attach_aspect_ratio_property(connector);
> drm_connector_attach_content_type_property(connector);
> connector->state->picture_aspect_ratio = HDMI_PICTURE_ASPECT_NONE;
> +
> + if (!HAS_GMCH_DISPLAY(dev_priv))
> + drm_connector_attach_max_bpc_property(connector, 8, 12);
> }
>
> /*
> --
> 2.9.3
--
Ville Syrjälä
Intel
_______________________________________________
dri-devel mailing list
dri-devel@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/dri-devel
