[Intel-gfx] [PATCH v2 rebased 07/11] drm/i915/tgl: Select master transcoder for MST stream

Souza, Jose jose.souza at intel.com
Mon Dec 16 17:23:56 UTC 2019


On Fri, 2019-12-13 at 22:56 +0200, Ville Syrjälä wrote:
> On Thu, Dec 12, 2019 at 10:44:29PM +0200, Ville Syrjälä wrote:
> > On Wed, Dec 11, 2019 at 10:45:22AM -0800, José Roberto de Souza
> > wrote:
> > > On TGL the blending of all the streams have moved from DDI to
> > > transcoder, so now every transcoder working over the same MST
> > > port must
> > > send its stream to a master transcoder and master will send to
> > > DDI
> > > respecting the time slots.
> > > 
> > > So here adding all the CRTCs that shares the same MST stream if
> > > needed and computing their state again, it will pick the lowest
> > > pipe/transcoder among the ones in the same stream to be master.
> > > 
> > > Most of the time skl_commit_modeset_enables() enables pipes in a
> > > crescent order but due DDB overlapping it might not happen, this
> > > scenarios will be handled in the next patch.
> > > 
> > > v2:
> > > - Using recently added intel_crtc_state_reset() to set
> > > mst_master_transcoder to invalid transcoder for all non gen12 &
> > > MST
> > > code paths
> > > - Setting lowest pipe/transcoder as master, previously it was the
> > > first one but setting a predictable one will help in future MST e
> > > port sync integration
> > > - Moving to intel type as much as we can
> > > 
> > > BSpec: 50493
> > > BSpec: 49190
> > > Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > > Cc: Lucas De Marchi <lucas.demarchi at intel.com>
> > > Signed-off-by: José Roberto de Souza <jose.souza at intel.com>
> > > ---
> > >  drivers/gpu/drm/i915/display/intel_atomic.c   |  14 ++
> > >  drivers/gpu/drm/i915/display/intel_atomic.h   |   3 +
> > >  drivers/gpu/drm/i915/display/intel_ddi.c      |  14 +-
> > >  drivers/gpu/drm/i915/display/intel_display.c  |  13 +-
> > >  .../drm/i915/display/intel_display_types.h    |   3 +
> > >  drivers/gpu/drm/i915/display/intel_dp_mst.c   | 139
> > > ++++++++++++++++--
> > >  drivers/gpu/drm/i915/display/intel_dp_mst.h   |   5 +
> > >  7 files changed, 178 insertions(+), 13 deletions(-)
> > > 
> > > diff --git a/drivers/gpu/drm/i915/display/intel_atomic.c
> > > b/drivers/gpu/drm/i915/display/intel_atomic.c
> > > index 6e93a39a6fec..69a0430c4638 100644
> > > --- a/drivers/gpu/drm/i915/display/intel_atomic.c
> > > +++ b/drivers/gpu/drm/i915/display/intel_atomic.c
> > > @@ -206,6 +206,20 @@ intel_digital_connector_needs_modeset(struct
> > > intel_atomic_state *state,
> > >  	       (new_crtc &&
> > > drm_atomic_crtc_needs_modeset(&new_crtc_state->uapi));
> > >  }
> > >  
> > > +struct intel_digital_connector_state *
> > > +intel_atomic_get_digital_connector_state(struct
> > > intel_atomic_state *state,
> > > +					 struct intel_connector
> > > *connector)
> > > +{
> > > +	struct drm_connector_state *connector_state;
> > > +
> > > +	connector_state = drm_atomic_get_connector_state(&state->base,
> > > +							 &connector-
> > > >base);
> > > +	if (IS_ERR(connector_state))
> > > +		return ERR_CAST(connector_state);
> > > +
> > > +	return to_intel_digital_connector_state(connector_state);
> > > +}
> > > +
> > >  /**
> > >   * intel_crtc_duplicate_state - duplicate crtc state
> > >   * @crtc: drm crtc
> > > diff --git a/drivers/gpu/drm/i915/display/intel_atomic.h
> > > b/drivers/gpu/drm/i915/display/intel_atomic.h
> > > index ba9cc29a5865..6e8638d83d28 100644
> > > --- a/drivers/gpu/drm/i915/display/intel_atomic.h
> > > +++ b/drivers/gpu/drm/i915/display/intel_atomic.h
> > > @@ -35,6 +35,9 @@ struct drm_connector_state *
> > >  intel_digital_connector_duplicate_state(struct drm_connector
> > > *connector);
> > >  bool intel_digital_connector_needs_modeset(struct
> > > intel_atomic_state *state,
> > >  					   struct intel_connector
> > > *connector);
> > > +struct intel_digital_connector_state *
> > > +intel_atomic_get_digital_connector_state(struct
> > > intel_atomic_state *state,
> > > +					 struct intel_connector
> > > *connector);
> > >  
> > >  struct drm_crtc_state *intel_crtc_duplicate_state(struct
> > > drm_crtc *crtc);
> > >  void intel_crtc_destroy_state(struct drm_crtc *crtc,
> > > diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c
> > > b/drivers/gpu/drm/i915/display/intel_ddi.c
> > > index 5b6f32517c75..6ee5230045eb 100644
> > > --- a/drivers/gpu/drm/i915/display/intel_ddi.c
> > > +++ b/drivers/gpu/drm/i915/display/intel_ddi.c
> > > @@ -1903,8 +1903,13 @@
> > > intel_ddi_transcoder_func_reg_val_get(const struct
> > > intel_crtc_state *crtc_state)
> > >  		temp |= TRANS_DDI_MODE_SELECT_DP_MST;
> > >  		temp |= DDI_PORT_WIDTH(crtc_state->lane_count);
> > >  
> > > -		if (INTEL_GEN(dev_priv) >= 12)
> > > -			temp |=
> > > TRANS_DDI_MST_TRANSPORT_SELECT(crtc_state->cpu_transcoder);
> > > +		if (INTEL_GEN(dev_priv) >= 12) {
> > > +			enum transcoder master;
> > > +
> > > +			master = crtc_state->mst_master_transcoder;
> > > +			WARN_ON(master == INVALID_TRANSCODER);
> > > +			temp |= TRANS_DDI_MST_TRANSPORT_SELECT(master);
> > > +		}
> > >  	} else {
> > >  		temp |= TRANS_DDI_MODE_SELECT_DP_SST;
> > >  		temp |= DDI_PORT_WIDTH(crtc_state->lane_count);
> > > @@ -4377,6 +4382,11 @@ void intel_ddi_get_config(struct
> > > intel_encoder *encoder,
> > >  		pipe_config->output_types |= BIT(INTEL_OUTPUT_DP_MST);
> > >  		pipe_config->lane_count =
> > >  			((temp & DDI_PORT_WIDTH_MASK) >>
> > > DDI_PORT_WIDTH_SHIFT) + 1;
> > > +
> > > +		if (INTEL_GEN(dev_priv) >= 12)
> > > +			pipe_config->mst_master_transcoder =
> > > +					REG_FIELD_GET(TRANS_DDI_MST_TRA
> > > NSPORT_SELECT_MASK, temp);
> > > +
> > >  		intel_dp_get_m_n(intel_crtc, pipe_config);
> > >  		break;
> > >  	default:
> > > diff --git a/drivers/gpu/drm/i915/display/intel_display.c
> > > b/drivers/gpu/drm/i915/display/intel_display.c
> > > index 39b00a19d752..1cecce2f54f8 100644
> > > --- a/drivers/gpu/drm/i915/display/intel_display.c
> > > +++ b/drivers/gpu/drm/i915/display/intel_display.c
> > > @@ -46,6 +46,7 @@
> > >  #include "display/intel_crt.h"
> > >  #include "display/intel_ddi.h"
> > >  #include "display/intel_dp.h"
> > > +#include "display/intel_dp_mst.h"
> > >  #include "display/intel_dsi.h"
> > >  #include "display/intel_dvo.h"
> > >  #include "display/intel_gmbus.h"
> > > @@ -11663,6 +11664,7 @@ static void intel_crtc_state_reset(struct
> > > intel_crtc_state *crtc_state,
> > >  	crtc_state->hsw_workaround_pipe = INVALID_PIPE;
> > >  	crtc_state->output_format = INTEL_OUTPUT_FORMAT_INVALID;
> > >  	crtc_state->scaler_state.scaler_id = -1;
> > > +	crtc_state->mst_master_transcoder = INVALID_TRANSCODER;
> > >  }
> > >  
> > >  /* Returns the currently programmed mode of the given encoder.
> > > */
> > > @@ -12510,6 +12512,9 @@ static void intel_dump_pipe_config(const
> > > struct intel_crtc_state *pipe_config,
> > >  			      pipe_config->csc_mode, pipe_config-
> > > >gamma_mode,
> > >  			      pipe_config->gamma_enable, pipe_config-
> > > >csc_enable);
> > >  
> > > +	DRM_DEBUG_KMS("MST master transcoder: %s\n",
> > > +		      transcoder_name(pipe_config-
> > > >mst_master_transcoder));
> > > +
> > >  dump_planes:
> > >  	if (!state)
> > >  		return;
> > > @@ -12651,6 +12656,7 @@ intel_crtc_prepare_cleared_state(struct
> > > intel_crtc_state *crtc_state)
> > >  	memcpy(saved_state->icl_port_dplls, crtc_state->icl_port_dplls,
> > >  	       sizeof(saved_state->icl_port_dplls));
> > >  	saved_state->crc_enabled = crtc_state->crc_enabled;
> > > +	saved_state->mst_master_transcoder = INVALID_TRANSCODER;
> > >  	if (IS_G4X(dev_priv) ||
> > >  	    IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv))
> > >  		saved_state->wm = crtc_state->wm;
> > > @@ -13290,6 +13296,8 @@ intel_pipe_config_compare(const struct
> > > intel_crtc_state *current_config,
> > >  	PIPE_CONF_CHECK_I(dsc.dsc_split);
> > >  	PIPE_CONF_CHECK_I(dsc.compressed_bpp);
> > >  
> > > +	PIPE_CONF_CHECK_I(mst_master_transcoder);
> > > +
> > >  #undef PIPE_CONF_CHECK_X
> > >  #undef PIPE_CONF_CHECK_I
> > >  #undef PIPE_CONF_CHECK_BOOL
> > > @@ -14374,7 +14382,7 @@ static void
> > > intel_commit_modeset_disables(struct intel_atomic_state *state)
> > >  	u32 handled = 0;
> > >  	int i;
> > >  
> > > -	/* Only disable port sync slaves */
> > > +	/* Only disable port sync and MST slaves */
> > >  	for_each_oldnew_intel_crtc_in_state(state, crtc,
> > > old_crtc_state,
> > >  					    new_crtc_state, i) {
> > >  		if (!needs_modeset(new_crtc_state))
> > > @@ -14388,7 +14396,8 @@ static void
> > > intel_commit_modeset_disables(struct intel_atomic_state *state)
> > >  		 * slave CRTCs are disabled first and then master CRTC
> > > since
> > >  		 * Slave vblanks are masked till Master Vblanks.
> > >  		 */
> > > -		if (!is_trans_port_sync_slave(old_crtc_state))
> > > +		if (!is_trans_port_sync_slave(old_crtc_state) &&
> > > +		    !intel_dp_mst_is_slave_trans(old_crtc_state))
> > >  			continue;
> > >  
> > >  		intel_pre_plane_update(state, crtc);
> > > diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h
> > > b/drivers/gpu/drm/i915/display/intel_display_types.h
> > > index 83ea04149b77..630a94892b7b 100644
> > > --- a/drivers/gpu/drm/i915/display/intel_display_types.h
> > > +++ b/drivers/gpu/drm/i915/display/intel_display_types.h
> > > @@ -1054,6 +1054,9 @@ struct intel_crtc_state {
> > >  
> > >  	/* Bitmask to indicate slaves attached */
> > >  	u8 sync_mode_slaves_mask;
> > > +
> > > +	/* Only valid on TGL+ */
> > > +	enum transcoder mst_master_transcoder;
> > >  };
> > >  
> > >  struct intel_crtc {
> > > diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c
> > > b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> > > index 926e49f449a6..12f5e799d91f 100644
> > > --- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
> > > +++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> > > @@ -87,6 +87,49 @@ static int
> > > intel_dp_mst_compute_link_config(struct intel_encoder *encoder,
> > >  	return 0;
> > >  }
> > >  
> > > +/*
> > > + * Iterate over all connectors and set mst_master_transcoder to
> > > the smallest
> > > + * transcoder id that shares the same MST connector.
> > > + */
> > > +static int
> > > +intel_dp_mst_master_trans_compute(struct intel_encoder *encoder,
> > > +				  struct intel_crtc_state *crtc_state,
> > > +				  struct drm_connector_state
> > > *connector_state)
> > > +{
> > > +	struct intel_atomic_state *state =
> > > to_intel_atomic_state(crtc_state->uapi.state);
> > > +	struct intel_connector *connector =
> > > to_intel_connector(connector_state->connector);
> > > +	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
> > > +	struct intel_digital_connector_state *iter_connector_state;
> > > +	struct intel_connector *iter_connector;
> > > +	int i;
> > > +
> > > +	if (INTEL_GEN(dev_priv) < 12)
> > > +		return 0;
> > > +
> > > +	crtc_state->mst_master_transcoder = I915_MAX_TRANSCODERS;
> > > +
> > > +	for_each_new_intel_connector_in_state(state, iter_connector,
> > > +					      iter_connector_state, i)
> > > {
> > > +		struct intel_crtc_state *iter_crtc_state;
> > > +		struct intel_crtc *iter_crtc;
> > > +
> > > +		if (connector->mst_port != iter_connector->mst_port ||
> > > +		    !iter_connector_state->base.crtc)
> > > +			continue;
> > > +
> > > +		iter_crtc = to_intel_crtc(iter_connector_state-
> > > >base.crtc);
> > > +		iter_crtc_state =
> > > intel_atomic_get_new_crtc_state(state,
> > > +								  iter_
> > > crtc);
> > > +		if (!iter_crtc_state->uapi.active)
> > > +			continue;
> > > +
> > > +		if (iter_crtc_state->cpu_transcoder < crtc_state-
> > > >mst_master_transcoder)
> > > +			crtc_state->mst_master_transcoder =
> > > iter_crtc_state->cpu_transcoder;
> 
> Was just reading Manasi's port sync stuff when I realized this won't
> work. We haven't necessarily compute cpu_transcoder for the other
> pipes yet. So I suggest we extract the code to compute the
> cpu_transcoder
> from intel_ddi_connector_get_hw_state() and use it everywhere,
> including
> here.

okay

> 
> > > +	}
> > > +
> > > +	return 0;
> > > +}
> > 
> > This looks like it can be a pure function that returns the
> > master transcoder.
> > 
> > > +
> > >  static int intel_dp_mst_compute_config(struct intel_encoder
> > > *encoder,
> > >  				       struct intel_crtc_state
> > > *pipe_config,
> > >  				       struct drm_connector_state
> > > *conn_state)
> > > @@ -154,24 +197,88 @@ static int
> > > intel_dp_mst_compute_config(struct intel_encoder *encoder,
> > >  
> > >  	intel_ddi_compute_min_voltage_level(dev_priv, pipe_config);
> > >  
> > > +	ret = intel_dp_mst_master_trans_compute(encoder, pipe_config,
> > > +						conn_state);
> > > +	if (ret)
> > > +		return ret;
> > > +
> > > +	return 0;
> > > +}
> > > +
> > > +/*
> > > + * If one of the connectors in a MST stream needs a modeset,
> > > mark all CRTCs
> > > + * that have a connector in the same MST stream as mode changed,
> > > + * intel_modeset_pipe_config()+intel_crtc_check_fastset() will
> > > take to do a
> > > + * fastset when possible.
> > > + */
> > > +static int
> > > +intel_dp_mst_atomic_master_trans_check(struct intel_connector
> > > *connector,
> > > +				       struct intel_atomic_state
> > > *state)
> > > +{
> > > +	struct drm_i915_private *dev_priv = to_i915(state->base.dev);
> > > +	struct drm_connector_list_iter connector_list_iter;
> > > +	struct intel_connector *connector_iter;
> > > +
> > > +	if (INTEL_GEN(dev_priv) < 12)
> > > +		return  0;
> > > +
> > > +	if (!intel_digital_connector_needs_modeset(state, connector))
> > > +		return 0;
> > > +
> > > +	drm_connector_list_iter_begin(&dev_priv->drm,
> > > &connector_list_iter);
> > > +	for_each_intel_connector_iter(connector_iter,
> > > &connector_list_iter) {
> > > +		struct intel_digital_connector_state
> > > *connector_iter_state;
> > > +		struct intel_crtc_state *crtc_state;
> > > +		struct intel_crtc *crtc;
> > > +
> > > +		if (connector_iter->mst_port != connector->mst_port)
> > > +			continue;
> > 
> > Do we need to exclude the connector itself? I guess not really?
> > 
> > > +
> > > +		connector_iter_state =
> > > +			intel_atomic_get_digital_connector_state(state,
> > > +								 connec
> > > tor_iter);
> > > +		if (IS_ERR(connector_iter_state)) {
> > > +			drm_connector_list_iter_end(&connector_list_ite
> > > r);
> > > +			return PTR_ERR(connector_iter_state);
> > > +		}
> > > +
> > > +		if (!connector_iter_state->base.crtc)
> > > +			continue;
> > > +
> > > +		crtc = to_intel_crtc(connector_iter_state->base.crtc);
> > > +		crtc_state = intel_atomic_get_crtc_state(&state->base,
> > > crtc);
> > > +		if (IS_ERR(crtc_state)) {
> > > +			drm_connector_list_iter_end(&connector_list_ite
> > > r);
> > > +			return PTR_ERR(crtc_state);
> > > +		}
> > > +
> > > +		crtc_state->uapi.mode_changed = true;
> > > +	}
> > > +	drm_connector_list_iter_end(&connector_list_iter);
> > > +
> > >  	return 0;
> > >  }
> > >  
> > >  static int
> > >  intel_dp_mst_atomic_check(struct drm_connector *connector,
> > > -			  struct drm_atomic_state *state)
> > > +			  struct drm_atomic_state *_state)
> > >  {
> > > +	struct intel_atomic_state *state =
> > > to_intel_atomic_state(_state);
> > >  	struct drm_connector_state *new_conn_state =
> > > -		drm_atomic_get_new_connector_state(state, connector);
> > > +		drm_atomic_get_new_connector_state(&state->base,
> > > connector);
> > >  	struct drm_connector_state *old_conn_state =
> > > -		drm_atomic_get_old_connector_state(state, connector);
> > > +		drm_atomic_get_old_connector_state(&state->base,
> > > connector);
> > >  	struct intel_connector *intel_connector =
> > >  		to_intel_connector(connector);
> > >  	struct drm_crtc *new_crtc = new_conn_state->crtc;
> > >  	struct drm_dp_mst_topology_mgr *mgr;
> > >  	int ret;
> > >  
> > > -	ret = intel_digital_connector_atomic_check(connector, state);
> > > +	ret = intel_digital_connector_atomic_check(connector, &state-
> > > >base);
> > > +	if (ret)
> > > +		return ret;
> > > +
> > > +	ret = intel_dp_mst_atomic_master_trans_check(intel_connector,
> > > state);
> > >  	if (ret)
> > >  		return ret;
> > >  
> > > @@ -182,12 +289,9 @@ intel_dp_mst_atomic_check(struct
> > > drm_connector *connector,
> > >  	 * connector
> > >  	 */
> > >  	if (new_crtc) {
> > > -		struct intel_atomic_state *intel_state =
> > > -			to_intel_atomic_state(state);
> > >  		struct intel_crtc *intel_crtc =
> > > to_intel_crtc(new_crtc);
> > >  		struct intel_crtc_state *crtc_state =
> > > -			intel_atomic_get_new_crtc_state(intel_state,
> > > -							intel_crtc);
> > > +			intel_atomic_get_new_crtc_state(state,
> > > intel_crtc);
> > >  
> > >  		if (!crtc_state ||
> > >  		    !drm_atomic_crtc_needs_modeset(&crtc_state->uapi)
> > > ||
> > > @@ -196,7 +300,7 @@ intel_dp_mst_atomic_check(struct
> > > drm_connector *connector,
> > >  	}
> > >  
> > >  	mgr = &enc_to_mst(old_conn_state->best_encoder)->primary-
> > > >dp.mst_mgr;
> > > -	ret = drm_dp_atomic_release_vcpi_slots(state, mgr,
> > > +	ret = drm_dp_atomic_release_vcpi_slots(&state->base, mgr,
> > >  					       intel_connector->port);
> > >  
> > >  	return ret;
> > > @@ -241,6 +345,9 @@ static void intel_mst_post_disable_dp(struct
> > > intel_encoder *encoder,
> > >  	intel_dp->active_mst_links--;
> > >  	last_mst_stream = intel_dp->active_mst_links == 0;
> > >  
> > > +	WARN_ON(INTEL_GEN(dev_priv) >= 12 && last_mst_stream &&
> > > +		!intel_dp_mst_is_master_trans(old_crtc_state));
> > > +
> > >  	/*
> > >  	 * From TGL spec: "If multi-stream slave transcoder: Configure
> > >  	 * Transcoder Clock Select to direct no clock to the
> > > transcoder"
> > > @@ -321,6 +428,9 @@ static void intel_mst_pre_enable_dp(struct
> > > intel_encoder *encoder,
> > >  	intel_mst->connector = connector;
> > >  	first_mst_stream = intel_dp->active_mst_links == 0;
> > >  
> > > +	WARN_ON(INTEL_GEN(dev_priv) >= 12 && first_mst_stream &&
> > > +		!intel_dp_mst_is_master_trans(pipe_config));
> > > +
> > >  	DRM_DEBUG_KMS("active links %d\n", intel_dp->active_mst_links);
> > >  
> > >  	if (first_mst_stream)
> > > @@ -726,3 +836,14 @@ intel_dp_mst_encoder_cleanup(struct
> > > intel_digital_port *intel_dig_port)
> > >  	drm_dp_mst_topology_mgr_destroy(&intel_dp->mst_mgr);
> > >  	/* encoders will get killed by normal cleanup */
> > >  }
> > > +
> > > +bool intel_dp_mst_is_master_trans(const struct intel_crtc_state
> > > *crtc_state)
> > > +{
> > > +	return crtc_state->mst_master_transcoder == crtc_state-
> > > >cpu_transcoder;
> > > +}
> > > +
> > > +bool intel_dp_mst_is_slave_trans(const struct intel_crtc_state
> > > *crtc_state)
> > > +{
> > > +	return crtc_state->mst_master_transcoder != INVALID_TRANSCODER
> > > &&
> > > +	       crtc_state->mst_master_transcoder != crtc_state-
> > > >cpu_transcoder;
> > > +}
> > > diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.h
> > > b/drivers/gpu/drm/i915/display/intel_dp_mst.h
> > > index f660ad80db04..e40767f78343 100644
> > > --- a/drivers/gpu/drm/i915/display/intel_dp_mst.h
> > > +++ b/drivers/gpu/drm/i915/display/intel_dp_mst.h
> > > @@ -6,10 +6,15 @@
> > >  #ifndef __INTEL_DP_MST_H__
> > >  #define __INTEL_DP_MST_H__
> > >  
> > > +#include <stdbool.h>
> > 
> > That doesn't seem like something you want to include in kernel
> > code.
> > 
> > > +
> > >  struct intel_digital_port;
> > > +struct intel_crtc_state;
> > >  
> > >  int intel_dp_mst_encoder_init(struct intel_digital_port
> > > *intel_dig_port, int conn_id);
> > >  void intel_dp_mst_encoder_cleanup(struct intel_digital_port
> > > *intel_dig_port);
> > >  int intel_dp_mst_encoder_active_links(struct intel_digital_port
> > > *intel_dig_port);
> > > +bool intel_dp_mst_is_master_trans(const struct intel_crtc_state
> > > *crtc_state);
> > > +bool intel_dp_mst_is_slave_trans(const struct intel_crtc_state
> > > *crtc_state);
> > >  
> > >  #endif /* __INTEL_DP_MST_H__ */
> > > -- 
> > > 2.24.1
> > 
> > -- 
> > Ville Syrjälä
> > Intel


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