[12/23] drm/i915: Sanitize the TypeC connect/detect sequences

Submitted by Imre Deak on June 4, 2019, 2:58 p.m.

Details

Message ID 20190604145826.16424-13-imre.deak@intel.com
State New
Headers show
Series "drm/i915: Fix TypeC port mode switching" ( rev: 2 1 ) in Intel GFX

Not browsing as part of any series.

Commit Message

Imre Deak June 4, 2019, 2:58 p.m.
Make the order during detection more consistent: first reset the TypeC
port mode if needed (adding new helpers for this), then detect any
connected sink.

To check if a port mode reset is needed determine first the target port
mode based on the live status if a sink is already connected or the
PHY status complete flag otherwise.

Add a WARN in legacy mode if unexpectedly we can't set the unsafe mode
or if the FIA doesn't provide the 4 lanes required.

Cc: José Roberto de Souza <jose.souza@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
---
 drivers/gpu/drm/i915/intel_tc.c | 104 +++++++++++++++-----------------
 1 file changed, 50 insertions(+), 54 deletions(-)

Patch hide | download patch | download mbox

diff --git a/drivers/gpu/drm/i915/intel_tc.c b/drivers/gpu/drm/i915/intel_tc.c
index d91381c0e87d..9832e2ddb92e 100644
--- a/drivers/gpu/drm/i915/intel_tc.c
+++ b/drivers/gpu/drm/i915/intel_tc.c
@@ -188,43 +188,46 @@  static bool icl_tc_phy_set_safe_mode(struct intel_digital_port *dig_port,
  * will require a lot of coordination with user space and thorough testing for
  * the extra possible cases.
  */
-static bool icl_tc_phy_connect(struct intel_digital_port *dig_port)
+static void icl_tc_phy_connect(struct intel_digital_port *dig_port)
 {
 	struct drm_i915_private *dev_priv = to_i915(dig_port->base.base.dev);
 	enum tc_port tc_port = intel_port_to_tc(dev_priv, dig_port->base.port);
-	u32 live_status_mask;
-
-	if (dig_port->tc_mode != TC_PORT_LEGACY &&
-	    dig_port->tc_mode != TC_PORT_DP_ALT)
-		return true;
 
 	if (!icl_tc_phy_status_complete(dig_port)) {
 		DRM_DEBUG_KMS("Port %s: PHY not ready\n",
 			      tc_port_name(dev_priv, tc_port));
-		WARN_ON(dig_port->tc_legacy_port);
-		return false;
+		goto out_set_tbt_alt_mode;
 	}
 
-	if (!icl_tc_phy_set_safe_mode(dig_port, false))
-		return false;
+	if (!icl_tc_phy_set_safe_mode(dig_port, false) &&
+	    !WARN_ON(dig_port->tc_legacy_port))
+		goto out_set_tbt_alt_mode;
 
-	if (dig_port->tc_mode == TC_PORT_LEGACY)
-		return true;
+	if (dig_port->tc_legacy_port) {
+		WARN_ON(intel_tc_port_fia_max_lane_count(dig_port) != 4);
+		dig_port->tc_mode = TC_PORT_LEGACY;
 
-	live_status_mask = tc_port_live_status_mask(dig_port);
+		return;
+	}
 
 	/*
 	 * Now we have to re-check the live state, in case the port recently
 	 * became disconnected. Not necessary for legacy mode.
 	 */
-	if (!(live_status_mask & BIT(TC_PORT_DP_ALT))) {
+	if (!(tc_port_live_status_mask(dig_port) & BIT(TC_PORT_DP_ALT))) {
 		DRM_DEBUG_KMS("Port %s: PHY sudden disconnect\n",
 			      tc_port_name(dev_priv, tc_port));
-		icl_tc_phy_disconnect(dig_port);
-		return false;
+		goto out_set_safe_mode;
 	}
 
-	return true;
+	dig_port->tc_mode = TC_PORT_DP_ALT;
+
+	return;
+
+out_set_safe_mode:
+	icl_tc_phy_set_safe_mode(dig_port, true);
+out_set_tbt_alt_mode:
+	dig_port->tc_mode = TC_PORT_TBT_ALT;
 }
 
 /*
@@ -233,9 +236,6 @@  static bool icl_tc_phy_connect(struct intel_digital_port *dig_port)
  */
 void icl_tc_phy_disconnect(struct intel_digital_port *dig_port)
 {
-	struct drm_i915_private *dev_priv = to_i915(dig_port->base.base.dev);
-	enum tc_port tc_port = intel_port_to_tc(dev_priv, dig_port->base.port);
-
 	switch (dig_port->tc_mode) {
 	case TC_PORT_LEGACY:
 	case TC_PORT_DP_ALT:
@@ -248,31 +248,41 @@  void icl_tc_phy_disconnect(struct intel_digital_port *dig_port)
 	default:
 		MISSING_CASE(dig_port->tc_mode);
 	}
-
-	DRM_DEBUG_KMS("Port %s: mode %s disconnected\n",
-		      tc_port_name(dev_priv, tc_port),
-		      tc_port_mode_name(dig_port->tc_mode));
 }
 
-static void icl_update_tc_port_type(struct drm_i915_private *dev_priv,
-				    struct intel_digital_port *intel_dig_port,
-				    u32 live_status_mask)
+static enum tc_port_mode
+intel_tc_port_get_target_mode(struct intel_digital_port *dig_port)
 {
-	enum port port = intel_dig_port->base.port;
-	enum tc_port_mode old_mode = intel_dig_port->tc_mode;
+	u32 live_status_mask = tc_port_live_status_mask(dig_port);
 
-	if (!live_status_mask)
-		return;
+	if (live_status_mask)
+		return fls(live_status_mask) - 1;
+
+	return icl_tc_phy_status_complete(dig_port) &&
+	       dig_port->tc_legacy_port ? TC_PORT_LEGACY :
+					  TC_PORT_TBT_ALT;
+}
 
-	intel_dig_port->tc_mode = fls(live_status_mask) - 1;
+static void intel_tc_port_reset_mode(struct intel_digital_port *dig_port)
+{
+	struct drm_i915_private *dev_priv = to_i915(dig_port->base.base.dev);
+	enum tc_port tc_port = intel_port_to_tc(dev_priv, dig_port->base.port);
+	enum tc_port_mode old_tc_mode = dig_port->tc_mode;
 
-	if (old_mode != intel_dig_port->tc_mode)
-		DRM_DEBUG_KMS("Port %s: port has mode %s\n",
-			      tc_port_name(dev_priv,
-					   intel_port_to_tc(dev_priv, port)),
-			      tc_port_mode_name(intel_dig_port->tc_mode));
+	icl_tc_phy_disconnect(dig_port);
+	icl_tc_phy_connect(dig_port);
+
+	DRM_DEBUG_KMS("Port %s: TC port mode reset (%s -> %s)\n",
+		      tc_port_name(dev_priv, tc_port),
+		      tc_port_mode_name(old_tc_mode),
+		      tc_port_mode_name(dig_port->tc_mode));
 }
 
+static bool
+intel_tc_port_needs_reset(struct intel_digital_port *dig_port)
+{
+	return intel_tc_port_get_target_mode(dig_port) != dig_port->tc_mode;
+}
 
 /*
  * The type-C ports are different because even when they are connected, they may
@@ -286,23 +296,9 @@  static void icl_update_tc_port_type(struct drm_i915_private *dev_priv,
  */
 bool intel_tc_port_connected(struct intel_digital_port *dig_port)
 {
-	struct drm_i915_private *dev_priv = to_i915(dig_port->base.base.dev);
-	u32 live_status_mask = tc_port_live_status_mask(dig_port);
+	if (intel_tc_port_needs_reset(dig_port))
+		intel_tc_port_reset_mode(dig_port);
 
-	/*
-	 * The spec says we shouldn't be using the ISR bits for detecting
-	 * between TC and TBT. We should use DFLEXDPSP.
-	 */
-	if (!live_status_mask && !dig_port->tc_legacy_port) {
-		icl_tc_phy_disconnect(dig_port);
-
-		return false;
-	}
-
-	icl_update_tc_port_type(dev_priv, dig_port, live_status_mask);
-	if (!icl_tc_phy_connect(dig_port))
-		return false;
-
-	return true;
+	return tc_port_live_status_mask(dig_port) & BIT(dig_port->tc_mode);
 }
 

Comments

On Tue, 2019-06-04 at 17:58 +0300, Imre Deak wrote:
> Make the order during detection more consistent: first reset the

> TypeC

> port mode if needed (adding new helpers for this), then detect any

> connected sink.

> 

> To check if a port mode reset is needed determine first the target

> port

> mode based on the live status if a sink is already connected or the

> PHY status complete flag otherwise.

> 

> Add a WARN in legacy mode if unexpectedly we can't set the unsafe

> mode

> or if the FIA doesn't provide the 4 lanes required.

> 

> Cc: José Roberto de Souza <jose.souza@intel.com>

> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>

> Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>

> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>

> Signed-off-by: Imre Deak <imre.deak@intel.com>

> ---

>  drivers/gpu/drm/i915/intel_tc.c | 104 +++++++++++++++---------------

> --

>  1 file changed, 50 insertions(+), 54 deletions(-)

> 

> diff --git a/drivers/gpu/drm/i915/intel_tc.c

> b/drivers/gpu/drm/i915/intel_tc.c

> index d91381c0e87d..9832e2ddb92e 100644

> --- a/drivers/gpu/drm/i915/intel_tc.c

> +++ b/drivers/gpu/drm/i915/intel_tc.c

> @@ -188,43 +188,46 @@ static bool icl_tc_phy_set_safe_mode(struct

> intel_digital_port *dig_port,

>   * will require a lot of coordination with user space and thorough

> testing for

>   * the extra possible cases.

>   */

> -static bool icl_tc_phy_connect(struct intel_digital_port *dig_port)

> +static void icl_tc_phy_connect(struct intel_digital_port *dig_port)

>  {

>  	struct drm_i915_private *dev_priv = to_i915(dig_port-

> >base.base.dev);

>  	enum tc_port tc_port = intel_port_to_tc(dev_priv, dig_port-

> >base.port);

> -	u32 live_status_mask;

> -

> -	if (dig_port->tc_mode != TC_PORT_LEGACY &&

> -	    dig_port->tc_mode != TC_PORT_DP_ALT)

> -		return true;

>  

>  	if (!icl_tc_phy_status_complete(dig_port)) {

>  		DRM_DEBUG_KMS("Port %s: PHY not ready\n",

>  			      tc_port_name(dev_priv, tc_port));

> -		WARN_ON(dig_port->tc_legacy_port);

> -		return false;

> +		goto out_set_tbt_alt_mode;

>  	}

>  

> -	if (!icl_tc_phy_set_safe_mode(dig_port, false))

> -		return false;

> +	if (!icl_tc_phy_set_safe_mode(dig_port, false) &&

> +	    !WARN_ON(dig_port->tc_legacy_port))

> +		goto out_set_tbt_alt_mode;

>  

> -	if (dig_port->tc_mode == TC_PORT_LEGACY)

> -		return true;

> +	if (dig_port->tc_legacy_port) {

> +		WARN_ON(intel_tc_port_fia_max_lane_count(dig_port) !=

> 4);

> +		dig_port->tc_mode = TC_PORT_LEGACY;

>  

> -	live_status_mask = tc_port_live_status_mask(dig_port);

> +		return;

> +	}

>  

>  	/*

>  	 * Now we have to re-check the live state, in case the port

> recently

>  	 * became disconnected. Not necessary for legacy mode.

>  	 */

> -	if (!(live_status_mask & BIT(TC_PORT_DP_ALT))) {

> +	if (!(tc_port_live_status_mask(dig_port) &

> BIT(TC_PORT_DP_ALT))) {

>  		DRM_DEBUG_KMS("Port %s: PHY sudden disconnect\n",

>  			      tc_port_name(dev_priv, tc_port));

> -		icl_tc_phy_disconnect(dig_port);

> -		return false;

> +		goto out_set_safe_mode;

>  	}

>  

> -	return true;

> +	dig_port->tc_mode = TC_PORT_DP_ALT;

> +

> +	return;

> +

> +out_set_safe_mode:

> +	icl_tc_phy_set_safe_mode(dig_port, true);

> +out_set_tbt_alt_mode:

> +	dig_port->tc_mode = TC_PORT_TBT_ALT;

>  }

>  

>  /*

> @@ -233,9 +236,6 @@ static bool icl_tc_phy_connect(struct

> intel_digital_port *dig_port)

>   */

>  void icl_tc_phy_disconnect(struct intel_digital_port *dig_port)

>  {

> -	struct drm_i915_private *dev_priv = to_i915(dig_port-

> >base.base.dev);

> -	enum tc_port tc_port = intel_port_to_tc(dev_priv, dig_port-

> >base.port);

> -

>  	switch (dig_port->tc_mode) {

>  	case TC_PORT_LEGACY:

>  	case TC_PORT_DP_ALT:

> @@ -248,31 +248,41 @@ void icl_tc_phy_disconnect(struct

> intel_digital_port *dig_port)

>  	default:

>  		MISSING_CASE(dig_port->tc_mode);

>  	}

> -

> -	DRM_DEBUG_KMS("Port %s: mode %s disconnected\n",

> -		      tc_port_name(dev_priv, tc_port),

> -		      tc_port_mode_name(dig_port->tc_mode));

>  }

>  

> -static void icl_update_tc_port_type(struct drm_i915_private

> *dev_priv,

> -				    struct intel_digital_port

> *intel_dig_port,

> -				    u32 live_status_mask)

> +static enum tc_port_mode

> +intel_tc_port_get_target_mode(struct intel_digital_port *dig_port)

>  {

> -	enum port port = intel_dig_port->base.port;

> -	enum tc_port_mode old_mode = intel_dig_port->tc_mode;

> +	u32 live_status_mask = tc_port_live_status_mask(dig_port);

>  

> -	if (!live_status_mask)

> -		return;

> +	if (live_status_mask)

> +		return fls(live_status_mask) - 1;

> +

> +	return icl_tc_phy_status_complete(dig_port) &&

> +	       dig_port->tc_legacy_port ? TC_PORT_LEGACY :

> +					  TC_PORT_TBT_ALT;


This will return 0 or 1, never TC_PORT_LEGACY(2) because of the "&&".


-TOOMANYREFACTORS
Staring to love again huge patches :P

> +}

>  

> -	intel_dig_port->tc_mode = fls(live_status_mask) - 1;

> +static void intel_tc_port_reset_mode(struct intel_digital_port

> *dig_port)

> +{

> +	struct drm_i915_private *dev_priv = to_i915(dig_port-

> >base.base.dev);

> +	enum tc_port tc_port = intel_port_to_tc(dev_priv, dig_port-

> >base.port);

> +	enum tc_port_mode old_tc_mode = dig_port->tc_mode;

>  

> -	if (old_mode != intel_dig_port->tc_mode)

> -		DRM_DEBUG_KMS("Port %s: port has mode %s\n",

> -			      tc_port_name(dev_priv,

> -					   intel_port_to_tc(dev_priv,

> port)),

> -			      tc_port_mode_name(intel_dig_port-

> >tc_mode));

> +	icl_tc_phy_disconnect(dig_port);

> +	icl_tc_phy_connect(dig_port);

> +

> +	DRM_DEBUG_KMS("Port %s: TC port mode reset (%s -> %s)\n",

> +		      tc_port_name(dev_priv, tc_port),

> +		      tc_port_mode_name(old_tc_mode),

> +		      tc_port_mode_name(dig_port->tc_mode));

>  }

>  

> +static bool

> +intel_tc_port_needs_reset(struct intel_digital_port *dig_port)

> +{

> +	return intel_tc_port_get_target_mode(dig_port) != dig_port-

> >tc_mode;

> +}

>  

>  /*

>   * The type-C ports are different because even when they are

> connected, they may

> @@ -286,23 +296,9 @@ static void icl_update_tc_port_type(struct

> drm_i915_private *dev_priv,

>   */

>  bool intel_tc_port_connected(struct intel_digital_port *dig_port)

>  {

> -	struct drm_i915_private *dev_priv = to_i915(dig_port-

> >base.base.dev);

> -	u32 live_status_mask = tc_port_live_status_mask(dig_port);

> +	if (intel_tc_port_needs_reset(dig_port))

> +		intel_tc_port_reset_mode(dig_port);

>  

> -	/*

> -	 * The spec says we shouldn't be using the ISR bits for

> detecting

> -	 * between TC and TBT. We should use DFLEXDPSP.

> -	 */

> -	if (!live_status_mask && !dig_port->tc_legacy_port) {

> -		icl_tc_phy_disconnect(dig_port);

> -

> -		return false;

> -	}

> -

> -	icl_update_tc_port_type(dev_priv, dig_port, live_status_mask);

> -	if (!icl_tc_phy_connect(dig_port))

> -		return false;

> -

> -	return true;

> +	return tc_port_live_status_mask(dig_port) & BIT(dig_port-

> >tc_mode);

>  }

>
On Sat, Jun 08, 2019 at 01:15:44AM +0300, Souza, Jose wrote:
> On Tue, 2019-06-04 at 17:58 +0300, Imre Deak wrote:
> > Make the order during detection more consistent: first reset the
> > TypeC
> > port mode if needed (adding new helpers for this), then detect any
> > connected sink.
> > 
> > To check if a port mode reset is needed determine first the target
> > port
> > mode based on the live status if a sink is already connected or the
> > PHY status complete flag otherwise.
> > 
> > Add a WARN in legacy mode if unexpectedly we can't set the unsafe
> > mode
> > or if the FIA doesn't provide the 4 lanes required.
> > 
> > Cc: José Roberto de Souza <jose.souza@intel.com>
> > Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
> > Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
> > Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
> > Signed-off-by: Imre Deak <imre.deak@intel.com>
> > ---
> >  drivers/gpu/drm/i915/intel_tc.c | 104 +++++++++++++++---------------
> > --
> >  1 file changed, 50 insertions(+), 54 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/intel_tc.c
> > b/drivers/gpu/drm/i915/intel_tc.c
> > index d91381c0e87d..9832e2ddb92e 100644
> > --- a/drivers/gpu/drm/i915/intel_tc.c
> > +++ b/drivers/gpu/drm/i915/intel_tc.c
> > @@ -188,43 +188,46 @@ static bool icl_tc_phy_set_safe_mode(struct
> > intel_digital_port *dig_port,
> >   * will require a lot of coordination with user space and thorough
> > testing for
> >   * the extra possible cases.
> >   */
> > -static bool icl_tc_phy_connect(struct intel_digital_port *dig_port)
> > +static void icl_tc_phy_connect(struct intel_digital_port *dig_port)
> >  {
> >  	struct drm_i915_private *dev_priv = to_i915(dig_port-
> > >base.base.dev);
> >  	enum tc_port tc_port = intel_port_to_tc(dev_priv, dig_port-
> > >base.port);
> > -	u32 live_status_mask;
> > -
> > -	if (dig_port->tc_mode != TC_PORT_LEGACY &&
> > -	    dig_port->tc_mode != TC_PORT_DP_ALT)
> > -		return true;
> >  
> >  	if (!icl_tc_phy_status_complete(dig_port)) {
> >  		DRM_DEBUG_KMS("Port %s: PHY not ready\n",
> >  			      tc_port_name(dev_priv, tc_port));
> > -		WARN_ON(dig_port->tc_legacy_port);
> > -		return false;
> > +		goto out_set_tbt_alt_mode;
> >  	}
> >  
> > -	if (!icl_tc_phy_set_safe_mode(dig_port, false))
> > -		return false;
> > +	if (!icl_tc_phy_set_safe_mode(dig_port, false) &&
> > +	    !WARN_ON(dig_port->tc_legacy_port))
> > +		goto out_set_tbt_alt_mode;
> >  
> > -	if (dig_port->tc_mode == TC_PORT_LEGACY)
> > -		return true;
> > +	if (dig_port->tc_legacy_port) {
> > +		WARN_ON(intel_tc_port_fia_max_lane_count(dig_port) !=
> > 4);
> > +		dig_port->tc_mode = TC_PORT_LEGACY;
> >  
> > -	live_status_mask = tc_port_live_status_mask(dig_port);
> > +		return;
> > +	}
> >  
> >  	/*
> >  	 * Now we have to re-check the live state, in case the port
> > recently
> >  	 * became disconnected. Not necessary for legacy mode.
> >  	 */
> > -	if (!(live_status_mask & BIT(TC_PORT_DP_ALT))) {
> > +	if (!(tc_port_live_status_mask(dig_port) &
> > BIT(TC_PORT_DP_ALT))) {
> >  		DRM_DEBUG_KMS("Port %s: PHY sudden disconnect\n",
> >  			      tc_port_name(dev_priv, tc_port));
> > -		icl_tc_phy_disconnect(dig_port);
> > -		return false;
> > +		goto out_set_safe_mode;
> >  	}
> >  
> > -	return true;
> > +	dig_port->tc_mode = TC_PORT_DP_ALT;
> > +
> > +	return;
> > +
> > +out_set_safe_mode:
> > +	icl_tc_phy_set_safe_mode(dig_port, true);
> > +out_set_tbt_alt_mode:
> > +	dig_port->tc_mode = TC_PORT_TBT_ALT;
> >  }
> >  
> >  /*
> > @@ -233,9 +236,6 @@ static bool icl_tc_phy_connect(struct
> > intel_digital_port *dig_port)
> >   */
> >  void icl_tc_phy_disconnect(struct intel_digital_port *dig_port)
> >  {
> > -	struct drm_i915_private *dev_priv = to_i915(dig_port-
> > >base.base.dev);
> > -	enum tc_port tc_port = intel_port_to_tc(dev_priv, dig_port-
> > >base.port);
> > -
> >  	switch (dig_port->tc_mode) {
> >  	case TC_PORT_LEGACY:
> >  	case TC_PORT_DP_ALT:
> > @@ -248,31 +248,41 @@ void icl_tc_phy_disconnect(struct
> > intel_digital_port *dig_port)
> >  	default:
> >  		MISSING_CASE(dig_port->tc_mode);
> >  	}
> > -
> > -	DRM_DEBUG_KMS("Port %s: mode %s disconnected\n",
> > -		      tc_port_name(dev_priv, tc_port),
> > -		      tc_port_mode_name(dig_port->tc_mode));
> >  }
> >  
> > -static void icl_update_tc_port_type(struct drm_i915_private
> > *dev_priv,
> > -				    struct intel_digital_port
> > *intel_dig_port,
> > -				    u32 live_status_mask)
> > +static enum tc_port_mode
> > +intel_tc_port_get_target_mode(struct intel_digital_port *dig_port)
> >  {
> > -	enum port port = intel_dig_port->base.port;
> > -	enum tc_port_mode old_mode = intel_dig_port->tc_mode;
> > +	u32 live_status_mask = tc_port_live_status_mask(dig_port);
> >  
> > -	if (!live_status_mask)
> > -		return;
> > +	if (live_status_mask)
> > +		return fls(live_status_mask) - 1;
> > +
> > +	return icl_tc_phy_status_complete(dig_port) &&
> > +	       dig_port->tc_legacy_port ? TC_PORT_LEGACY :
> > +					  TC_PORT_TBT_ALT;
> 
> This will return 0 or 1, never TC_PORT_LEGACY(2) because of the "&&".

Nope, C operators precedence is first "&&" then "?:". Should be fine.

> -TOOMANYREFACTORS
> Staring to love again huge patches :P

Well all the previous refactorings should be easier to review, since
they don't change the functionality.

The hope was that the refactoring patches make the review of this one
- with functionality changes - easier to review.

> 
> > +}
> >  
> > -	intel_dig_port->tc_mode = fls(live_status_mask) - 1;
> > +static void intel_tc_port_reset_mode(struct intel_digital_port
> > *dig_port)
> > +{
> > +	struct drm_i915_private *dev_priv = to_i915(dig_port-
> > >base.base.dev);
> > +	enum tc_port tc_port = intel_port_to_tc(dev_priv, dig_port-
> > >base.port);
> > +	enum tc_port_mode old_tc_mode = dig_port->tc_mode;
> >  
> > -	if (old_mode != intel_dig_port->tc_mode)
> > -		DRM_DEBUG_KMS("Port %s: port has mode %s\n",
> > -			      tc_port_name(dev_priv,
> > -					   intel_port_to_tc(dev_priv,
> > port)),
> > -			      tc_port_mode_name(intel_dig_port-
> > >tc_mode));
> > +	icl_tc_phy_disconnect(dig_port);
> > +	icl_tc_phy_connect(dig_port);
> > +
> > +	DRM_DEBUG_KMS("Port %s: TC port mode reset (%s -> %s)\n",
> > +		      tc_port_name(dev_priv, tc_port),
> > +		      tc_port_mode_name(old_tc_mode),
> > +		      tc_port_mode_name(dig_port->tc_mode));
> >  }
> >  
> > +static bool
> > +intel_tc_port_needs_reset(struct intel_digital_port *dig_port)
> > +{
> > +	return intel_tc_port_get_target_mode(dig_port) != dig_port-
> > >tc_mode;
> > +}
> >  
> >  /*
> >   * The type-C ports are different because even when they are
> > connected, they may
> > @@ -286,23 +296,9 @@ static void icl_update_tc_port_type(struct
> > drm_i915_private *dev_priv,
> >   */
> >  bool intel_tc_port_connected(struct intel_digital_port *dig_port)
> >  {
> > -	struct drm_i915_private *dev_priv = to_i915(dig_port-
> > >base.base.dev);
> > -	u32 live_status_mask = tc_port_live_status_mask(dig_port);
> > +	if (intel_tc_port_needs_reset(dig_port))
> > +		intel_tc_port_reset_mode(dig_port);
> >  
> > -	/*
> > -	 * The spec says we shouldn't be using the ISR bits for
> > detecting
> > -	 * between TC and TBT. We should use DFLEXDPSP.
> > -	 */
> > -	if (!live_status_mask && !dig_port->tc_legacy_port) {
> > -		icl_tc_phy_disconnect(dig_port);
> > -
> > -		return false;
> > -	}
> > -
> > -	icl_update_tc_port_type(dev_priv, dig_port, live_status_mask);
> > -	if (!icl_tc_phy_connect(dig_port))
> > -		return false;
> > -
> > -	return true;
> > +	return tc_port_live_status_mask(dig_port) & BIT(dig_port-
> > >tc_mode);
> >  }
> >