At times 12bpc HDMI cannot be driven due to faulty cables, dongles level shifters etc. To workaround them we may need to drive the output at a lower bpc. Currently the user space does not have a way to limit the bpc. The default bpc to be programmed is decided by the driver and is run against connector limitations.
Creating a new connector property "max bpc" in order to limit the bpc. xrandr can make use of this connector property to make sure that bpc does not exceed the configured value. This property can be used by userspace to set the bpc.
V2: Initialize max_bpc to satisfy kms_properties V3: Move the property to drm_connector V4: Split drm and i915 components(Ville)
Cc: Ville Syrjälä ville.syrjala@linux.intel.com Cc: Kishore Kadiyala kishore.kadiyala@intel.com Cc: Rodrigo Vivi rodrigo.vivi@intel.com Cc: Manasi Navare manasi.d.navare@intel.com Cc: Stanislav Lisovskiy stanislav.lisovskiy@intel.com Signed-off-by: Radhakrishna Sripada radhakrishna.sripada@intel.com --- drivers/gpu/drm/drm_atomic.c | 4 ++++ drivers/gpu/drm/drm_atomic_helper.c | 4 ++++ include/drm/drm_connector.h | 6 ++++++ include/drm/drm_mode_config.h | 5 +++++ 4 files changed, 19 insertions(+)
diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c index d0478abc01bd..4e352fc1f0a0 100644 --- a/drivers/gpu/drm/drm_atomic.c +++ b/drivers/gpu/drm/drm_atomic.c @@ -1420,6 +1420,8 @@ static int drm_atomic_connector_set_property(struct drm_connector *connector,
return set_out_fence_for_connector(state->state, connector, fence_ptr); + } else if (property == config->max_bpc_property) { + state->max_bpc = val; } else if (connector->funcs->atomic_set_property) { return connector->funcs->atomic_set_property(connector, state, property, val); @@ -1515,6 +1517,8 @@ drm_atomic_connector_get_property(struct drm_connector *connector, *val = 0; } else if (property == config->writeback_out_fence_ptr_property) { *val = 0; + } else if (property == config->max_bpc_property) { + *val = state->max_bpc; } else if (connector->funcs->atomic_get_property) { return connector->funcs->atomic_get_property(connector, state, property, val); diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c index 2c23a48482da..7f763650a623 100644 --- a/drivers/gpu/drm/drm_atomic_helper.c +++ b/drivers/gpu/drm/drm_atomic_helper.c @@ -638,6 +638,10 @@ drm_atomic_helper_check_modeset(struct drm_device *dev, if (old_connector_state->link_status != new_connector_state->link_status) new_crtc_state->connectors_changed = true; + + if (old_connector_state->max_bpc != + new_connector_state->max_bpc) + new_crtc_state->connectors_changed = true; }
if (funcs->atomic_check) diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h index 97ea41dc678f..fc11f40aae51 100644 --- a/include/drm/drm_connector.h +++ b/include/drm/drm_connector.h @@ -460,6 +460,12 @@ struct drm_connector_state { * drm_writeback_signal_completion() */ struct drm_writeback_job *writeback_job; + + /** + * @max_bpc: Connector property to limit the maximum bit depth of + * the pixels. + */ + unsigned int max_bpc; };
/** diff --git a/include/drm/drm_mode_config.h b/include/drm/drm_mode_config.h index a0b202e1d69a..b9cd7a73b244 100644 --- a/include/drm/drm_mode_config.h +++ b/include/drm/drm_mode_config.h @@ -562,6 +562,11 @@ struct drm_mode_config { */ struct drm_property *link_status_property; /** + * @max_bpc_property: Default connector property for the max bpc to be + * driven out of the connector. + */ + struct drm_property *max_bpc_property; + /** * @plane_type_property: Default plane property to differentiate * CURSOR, PRIMARY and OVERLAY legacy uses of planes. */
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)
Cc: Ville Syrjälä ville.syrjala@linux.intel.com Cc: Rodrigo Vivi rodrigo.vivi@intel.com Cc: Kishore Kadiyala kishore.kadiyala@intel.com Cc: Manasi Navare manasi.d.navare@intel.com Cc: Stanislav Lisovskiy stanislav.lisovskiy@intel.com Signed-off-by: Radhakrishna Sripada radhakrishna.sripada@intel.com --- drivers/gpu/drm/i915/intel_display.c | 25 +++++++++++++++++++++++++ drivers/gpu/drm/i915/intel_dp.c | 1 + drivers/gpu/drm/i915/intel_drv.h | 2 ++ drivers/gpu/drm/i915/intel_hdmi.c | 7 +++++++ drivers/gpu/drm/i915/intel_modes.c | 21 +++++++++++++++++++++ 5 files changed, 56 insertions(+)
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 4bb46f289c0d..216fd4b689b5 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -10783,6 +10783,28 @@ connected_sink_compute_bpp(struct intel_connector *connector, } }
+static void +connected_sink_max_bpp(struct drm_connector_state *conn_state, + struct intel_crtc_state *pipe_config) +{ + switch (conn_state->max_bpc) { + case 8: + case 9: + pipe_config->pipe_bpp = 8*3; + break; + case 10: + case 11: + pipe_config->pipe_bpp = 10*3; + break; + case 12: + pipe_config->pipe_bpp = 12*3; + break; + default: + break; + } + DRM_DEBUG_KMS("Limiting display bpp to %d\n", pipe_config->pipe_bpp); +} + static int compute_baseline_pipe_bpp(struct intel_crtc *crtc, struct intel_crtc_state *pipe_config) @@ -10811,6 +10833,9 @@ compute_baseline_pipe_bpp(struct intel_crtc *crtc, if (connector_state->crtc != &crtc->base) continue;
+ if (connector_state->max_bpc) + connected_sink_max_bpp(connector_state, pipe_config); + connected_sink_compute_bpp(to_intel_connector(connector), pipe_config); } diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index 436c22de33b6..1c2d38b7f6ab 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -5719,6 +5719,7 @@ 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); + intel_attach_max_bpc_property(connector, 6, 16);
if (intel_dp_is_edp(intel_dp)) { u32 allowed_scalers; diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h index f5731215210a..b3c703dacc92 100644 --- a/drivers/gpu/drm/i915/intel_drv.h +++ b/drivers/gpu/drm/i915/intel_drv.h @@ -1869,6 +1869,8 @@ int intel_ddc_get_modes(struct drm_connector *c, struct i2c_adapter *adapter); void intel_attach_force_audio_property(struct drm_connector *connector); void intel_attach_broadcast_rgb_property(struct drm_connector *connector); void intel_attach_aspect_ratio_property(struct drm_connector *connector); +void intel_attach_max_bpc_property(struct drm_connector *connector, int min, int + max);
/* intel_overlay.c */ diff --git a/drivers/gpu/drm/i915/intel_hdmi.c b/drivers/gpu/drm/i915/intel_hdmi.c index a2dab0b6bde6..e649bbf07642 100644 --- a/drivers/gpu/drm/i915/intel_hdmi.c +++ b/drivers/gpu/drm/i915/intel_hdmi.c @@ -2109,11 +2109,18 @@ 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)) + intel_attach_max_bpc_property(connector, 8, 8); + else + intel_attach_max_bpc_property(connector, 8, 12); }
/* diff --git a/drivers/gpu/drm/i915/intel_modes.c b/drivers/gpu/drm/i915/intel_modes.c index ca44bf368e24..eb1eaad0115e 100644 --- a/drivers/gpu/drm/i915/intel_modes.c +++ b/drivers/gpu/drm/i915/intel_modes.c @@ -133,3 +133,24 @@ intel_attach_aspect_ratio_property(struct drm_connector *connector) connector->dev->mode_config.aspect_ratio_property, DRM_MODE_PICTURE_ASPECT_NONE); } + +void +intel_attach_max_bpc_property(struct drm_connector *connector, int min, int + max) +{ + struct drm_device *dev = connector->dev; + struct drm_mode_config *config = &dev->mode_config; + struct drm_property *prop; + + prop = config->max_bpc_property; + if (prop == NULL) { + prop = drm_property_create_range(dev, 0, "max bpc", min, max); + if (prop == NULL) + return; + + config->max_bpc_property = prop; + } + + drm_object_attach_property(&connector->base, prop, max); + connector->state->max_bpc = max; +}
On Thu, Aug 30, 2018 at 08:06:48AM -0700, Radhakrishna Sripada wrote:
At times 12bpc HDMI cannot be driven due to faulty cables, dongles level shifters etc. To workaround them we may need to drive the output at a lower bpc. Currently the user space does not have a way to limit the bpc. The default bpc to be programmed is decided by the driver and is run against connector limitations.
Creating a new connector property "max bpc" in order to limit the bpc. xrandr can make use of this connector property to make sure that bpc does not exceed the configured value. This property can be used by userspace to set the bpc.
V2: Initialize max_bpc to satisfy kms_properties V3: Move the property to drm_connector V4: Split drm and i915 components(Ville)
Cc: Ville Syrjälä ville.syrjala@linux.intel.com Cc: Kishore Kadiyala kishore.kadiyala@intel.com Cc: Rodrigo Vivi rodrigo.vivi@intel.com Cc: Manasi Navare manasi.d.navare@intel.com Cc: Stanislav Lisovskiy stanislav.lisovskiy@intel.com Signed-off-by: Radhakrishna Sripada radhakrishna.sripada@intel.com
drivers/gpu/drm/drm_atomic.c | 4 ++++ drivers/gpu/drm/drm_atomic_helper.c | 4 ++++ include/drm/drm_connector.h | 6 ++++++ include/drm/drm_mode_config.h | 5 +++++ 4 files changed, 19 insertions(+)
diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c index d0478abc01bd..4e352fc1f0a0 100644 --- a/drivers/gpu/drm/drm_atomic.c +++ b/drivers/gpu/drm/drm_atomic.c @@ -1420,6 +1420,8 @@ static int drm_atomic_connector_set_property(struct drm_connector *connector,
return set_out_fence_for_connector(state->state, connector, fence_ptr);
- } else if (property == config->max_bpc_property) {
state->max_bpc = val;@@ -1515,6 +1517,8 @@ drm_atomic_connector_get_property(struct drm_connector *connector, *val = 0; } else if (property == config->writeback_out_fence_ptr_property) { *val = 0;
- } else if (property == config->max_bpc_property) {
*val = state->max_bpc;diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c index 2c23a48482da..7f763650a623 100644 --- a/drivers/gpu/drm/drm_atomic_helper.c +++ b/drivers/gpu/drm/drm_atomic_helper.c @@ -638,6 +638,10 @@ drm_atomic_helper_check_modeset(struct drm_device *dev, if (old_connector_state->link_status != new_connector_state->link_status) new_crtc_state->connectors_changed = true;
if (old_connector_state->max_bpc !=new_connector_state->max_bpc)new_crtc_state->connectors_changed = true;}
if (funcs->atomic_check)
diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h index 97ea41dc678f..fc11f40aae51 100644 --- a/include/drm/drm_connector.h +++ b/include/drm/drm_connector.h @@ -460,6 +460,12 @@ struct drm_connector_state { * drm_writeback_signal_completion() */ struct drm_writeback_job *writeback_job;
- /**
* @max_bpc: Connector property to limit the maximum bit depth of* the pixels.*/- unsigned int max_bpc;
};
/** diff --git a/include/drm/drm_mode_config.h b/include/drm/drm_mode_config.h index a0b202e1d69a..b9cd7a73b244 100644 --- a/include/drm/drm_mode_config.h +++ b/include/drm/drm_mode_config.h @@ -562,6 +562,11 @@ struct drm_mode_config { */ struct drm_property *link_status_property; /**
* @max_bpc_property: Default connector property for the max bpc to be* driven out of the connector.*/- struct drm_property *max_bpc_property;
If we want the exposed limits to be accurate this needs to be per-connector. The other option of course is to just expose the global min-max range for the entire device.
The way you wrote the i915 bits suggest you wanted to go for the per-connector apporach instead.
- /**
*/
- @plane_type_property: Default plane property to differentiate
- CURSOR, PRIMARY and OVERLAY legacy uses of planes.
-- 2.9.3
dri-devel@lists.freedesktop.org
-
Radhakrishna Sripada -
Ville Syrjälä