Re: [PATCH v4 03/11] drm/i915/power: Use intel_encoder_is_tc()

[Imre Deak <imre.deak@intel.com>]

On Fri, Nov 07, 2025 at 09:05:36PM -0300, Gustavo Sousa wrote:
> Starting with Xe3p_LPD, when intel_phy_is_tc() returns true, it does
> not necessarily mean that the port is connected to a PHY in the Type-C
> subsystem.  The reason is that there is now a VBT field called
> dedicated_external that will indicate that a Type-C capable port is
> connected to a (most likely) combo/dedicated PHY.  When that's the case,
> we must not do the extra programming required for Type-C connections.
> 
> In an upcoming change, we will modify intel_encoder_is_tc() to take the
> VBT field dedicated_external into consideration.  Update
> intel_display_power_well.c to use that function instead of
> intel_phy_is_tc().
> 
> Note that, even though icl_aux_power_well_{enable,disable} are not part
> of Xe3p_LPD's display paths, we modify them anyway for uniformity.
> 
> Cc: Shekhar Chauhan <shekhar.chauhan@intel.com>
> Reviewed-by: Suraj Kandpal <suraj.kandpal@intel.com>
> Signed-off-by: Gustavo Sousa <gustavo.sousa@intel.com>
> ---
>  .../drm/i915/display/intel_display_power_well.c    | 26 +++++++++++++++-------
>  1 file changed, 18 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_display_power_well.c b/drivers/gpu/drm/i915/display/intel_display_power_well.c
> index eab7019f2252..1485fc65ab87 100644
> --- a/drivers/gpu/drm/i915/display/intel_display_power_well.c
> +++ b/drivers/gpu/drm/i915/display/intel_display_power_well.c
> @@ -258,8 +258,9 @@ aux_ch_to_digital_port(struct intel_display *display,
>  	return NULL;
>  }
>  
> -static enum phy icl_aux_pw_to_phy(struct intel_display *display,
> -				  const struct i915_power_well *power_well)
> +static struct intel_encoder *
> +icl_aux_pw_to_encoder(struct intel_display *display,
> +		      const struct i915_power_well *power_well)
>  {
>  	enum aux_ch aux_ch = icl_aux_pw_to_ch(power_well);
>  	struct intel_digital_port *dig_port = aux_ch_to_digital_port(display, aux_ch);
> @@ -271,7 +272,15 @@ static enum phy icl_aux_pw_to_phy(struct intel_display *display,
>  	 * as HDMI-only and routed to a combo PHY, the encoder either won't be
>  	 * present at all or it will not have an aux_ch assigned.
>  	 */
> -	return dig_port ? intel_encoder_to_phy(&dig_port->base) : PHY_NONE;
> +	return dig_port ? &dig_port->base : NULL;
> +}
> +
> +static enum phy icl_aux_pw_to_phy(struct intel_display *display,
> +				  const struct i915_power_well *power_well)
> +{
> +	struct intel_encoder *encoder = icl_aux_pw_to_encoder(display, power_well);
> +
> +	return encoder ? intel_encoder_to_phy(encoder) : PHY_NONE;
>  }
>  
>  static void hsw_wait_for_power_well_enable(struct intel_display *display,
> @@ -570,9 +579,9 @@ static void
>  icl_aux_power_well_enable(struct intel_display *display,
>  			  struct i915_power_well *power_well)
>  {
> -	enum phy phy = icl_aux_pw_to_phy(display, power_well);
> +	struct intel_encoder *encoder = icl_aux_pw_to_encoder(display, power_well);
>  
> -	if (intel_phy_is_tc(display, phy))
> +	if (encoder && intel_encoder_is_tc(encoder))

Adding an icl_aux_pw_is_tc_phy(display, power_well) helper would
simplify things avoiding the need to retrieve the encoder.

>  		return icl_tc_phy_aux_power_well_enable(display, power_well);
>  	else if (display->platform.icelake)
>  		return icl_combo_phy_aux_power_well_enable(display,
> @@ -585,9 +594,9 @@ static void
>  icl_aux_power_well_disable(struct intel_display *display,
>  			   struct i915_power_well *power_well)
>  {
> -	enum phy phy = icl_aux_pw_to_phy(display, power_well);
> +	struct intel_encoder *encoder = icl_aux_pw_to_encoder(display, power_well);
>  
> -	if (intel_phy_is_tc(display, phy))
> +	if (encoder && intel_encoder_is_tc(encoder))
>  		return hsw_power_well_disable(display, power_well);
>  	else if (display->platform.icelake)
>  		return icl_combo_phy_aux_power_well_disable(display,
> @@ -1849,10 +1858,11 @@ tgl_tc_cold_off_power_well_is_enabled(struct intel_display *display,
>  static void xelpdp_aux_power_well_enable(struct intel_display *display,
>  					 struct i915_power_well *power_well)
>  {
> +	struct intel_encoder *encoder = icl_aux_pw_to_encoder(display, power_well);
>  	enum aux_ch aux_ch = i915_power_well_instance(power_well)->xelpdp.aux_ch;
>  	enum phy phy = icl_aux_pw_to_phy(display, power_well);
>  
> -	if (intel_phy_is_tc(display, phy))
> +	if (encoder && intel_encoder_is_tc(encoder))
>  		icl_tc_port_assert_ref_held(display, power_well,
>  					    aux_ch_to_digital_port(display, aux_ch));
>  
> 
> -- 
> 2.51.0
>