NACK/cmt: [PATCH v3 1/1][SRU][H] drm/i915: Force a TypeC PHY disconnect during suspend/shutdown

Tim Gardner tim.gardner at canonical.com
Mon Jul 19 14:28:58 UTC 2021


Backports of more then simple complexity generally deserve some 
explanation. In this case it looks like you've dropped a couple of 
functions.

On 7/16/21 2:48 AM, chris.chiu at canonical.com wrote:
> From: Imre Deak <imre.deak at intel.com>
> 
> BugLink: https://bugs.launchpad.net/bugs/1931072
> 
> Disconnect TypeC PHYs during system suspend and shutdown, even with the
> corresponding TypeC sink still plugged to its connector, since leaving
> the PHY connected causes havoc at least during system resume in the
> presence of an Nvidia card.
> 
> Note that this will only make a difference in the TypeC DP alternate
> mode, since in Thunderbolt alternate mode the PHY is never owned by the
> display engine and there is no notion of PHY ownership in legacy mode
> (the display engine being the only possible owner in that mode and the
> TypeC subsystem not having anything to do with the port in that case).
> 
> Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/3500
> Reported-and-tested-by: Chris Chiu <chris.chiu at canonical.com>
> Signed-off-by: Imre Deak <imre.deak at intel.com>
> Reviewed-by: Uma Shankar <uma.shankar at intel.com>
> Link: https://patchwork.freedesktop.org/patch/msgid/20210610174223.605904-1-imre.deak@intel.com
> (backported from commit 151ec347b06a2fb6ecd2922475dca71a7af827a5
> linux-next)
> Signed-off-by: Chris Chiu <chris.chiu at canonical.com>
> ---
>   drivers/gpu/drm/i915/display/intel_ddi.c | 34 ++++++++++++++++++++++--
>   drivers/gpu/drm/i915/display/intel_tc.c  | 34 +++++++++++++++++++-----
>   drivers/gpu/drm/i915/display/intel_tc.h  |  2 ++
>   3 files changed, 61 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c b/drivers/gpu/drm/i915/display/intel_ddi.c
> index cf665636408b..b272da304795 100644
> --- a/drivers/gpu/drm/i915/display/intel_ddi.c
> +++ b/drivers/gpu/drm/i915/display/intel_ddi.c
> @@ -5338,6 +5338,36 @@ static enum hpd_pin cnl_hpd_pin(struct drm_i915_private *dev_priv,
>   	return HPD_PORT_A + port - PORT_A;
>   }
>   
> +static void intel_ddi_encoder_suspend(struct intel_encoder *encoder)
> +{
> +	struct intel_dp *intel_dp = enc_to_intel_dp(encoder);
> +	struct drm_i915_private *i915 = dp_to_i915(intel_dp);
> +	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
> +	enum phy phy = intel_port_to_phy(i915, encoder->port);
> +
> +	intel_dp_encoder_suspend(encoder);
> +
> +	if (!intel_phy_is_tc(i915, phy))
> +		return;
> +
> +	intel_tc_port_disconnect_phy(dig_port);
> +}
> +
> +static void intel_ddi_encoder_shutdown(struct intel_encoder *encoder)
> +{
> +	struct intel_dp *intel_dp = enc_to_intel_dp(encoder);
> +	struct drm_i915_private *i915 = dp_to_i915(intel_dp);
> +	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
> +	enum phy phy = intel_port_to_phy(i915, encoder->port);
> +
> +	intel_dp_encoder_shutdown(encoder);
> +
> +	if (!intel_phy_is_tc(i915, phy))
> +		return;
> +
> +	intel_tc_port_disconnect_phy(dig_port);
> +}
> +
>   #define port_tc_name(port) ((port) - PORT_TC1 + '1')
>   #define tc_port_name(tc_port) ((tc_port) - TC_PORT_1 + '1')
>   
> @@ -5432,8 +5462,8 @@ void intel_ddi_init(struct drm_i915_private *dev_priv, enum port port)
>   	encoder->get_config = intel_ddi_get_config;
>   	encoder->sync_state = intel_ddi_sync_state;
>   	encoder->initial_fastset_check = intel_ddi_initial_fastset_check;
> -	encoder->suspend = intel_dp_encoder_suspend;
> -	encoder->shutdown = intel_dp_encoder_shutdown;
> +	encoder->suspend = intel_ddi_encoder_suspend;
> +	encoder->shutdown = intel_ddi_encoder_shutdown;
>   	encoder->get_power_domains = intel_ddi_get_power_domains;
>   
>   	encoder->type = INTEL_OUTPUT_DDI;
> diff --git a/drivers/gpu/drm/i915/display/intel_tc.c b/drivers/gpu/drm/i915/display/intel_tc.c
> index 8b6f16f9d0d1..2f4d7336d76e 100644
> --- a/drivers/gpu/drm/i915/display/intel_tc.c
> +++ b/drivers/gpu/drm/i915/display/intel_tc.c
> @@ -449,7 +449,7 @@ intel_tc_port_get_target_mode(struct intel_digital_port *dig_port)
>   }
>   
>   static void intel_tc_port_reset_mode(struct intel_digital_port *dig_port,
> -				     int required_lanes)
> +				     int required_lanes, bool force_disconnect)
>   {
>   	struct drm_i915_private *i915 = to_i915(dig_port->base.base.dev);
>   	enum tc_port_mode old_tc_mode = dig_port->tc_mode;
> @@ -465,7 +465,8 @@ static void intel_tc_port_reset_mode(struct intel_digital_port *dig_port,
>   	}
>   
>   	icl_tc_phy_disconnect(dig_port);
> -	icl_tc_phy_connect(dig_port, required_lanes);
> +	if (!force_disconnect)
> +		icl_tc_phy_connect(dig_port, required_lanes);
>   
>   	drm_dbg_kms(&i915->drm, "Port %s: TC port mode reset (%s -> %s)\n",
>   		    dig_port->tc_port_name,
> @@ -555,7 +556,7 @@ bool intel_tc_port_connected(struct intel_encoder *encoder)
>   }
>   
>   static void __intel_tc_port_lock(struct intel_digital_port *dig_port,
> -				 int required_lanes)
> +				 int required_lanes, bool force_disconnect)
>   {
>   	struct drm_i915_private *i915 = to_i915(dig_port->base.base.dev);
>   	intel_wakeref_t wakeref;
> @@ -569,8 +570,9 @@ static void __intel_tc_port_lock(struct intel_digital_port *dig_port,
>   
>   		tc_cold_wref = tc_cold_block(dig_port);
>   
> -		if (intel_tc_port_needs_reset(dig_port))
> -			intel_tc_port_reset_mode(dig_port, required_lanes);
> +		if (force_disconnect || intel_tc_port_needs_reset(dig_port))
> +			intel_tc_port_reset_mode(dig_port, required_lanes,
> +						 force_disconnect);
>   
>   		tc_cold_unblock(dig_port, tc_cold_wref);
>   	}
> @@ -581,7 +583,7 @@ static void __intel_tc_port_lock(struct intel_digital_port *dig_port,
>   
>   void intel_tc_port_lock(struct intel_digital_port *dig_port)
>   {
> -	__intel_tc_port_lock(dig_port, 1);
> +	__intel_tc_port_lock(dig_port, 1, false);
>   }
>   
>   void intel_tc_port_unlock(struct intel_digital_port *dig_port)
> @@ -595,6 +597,24 @@ void intel_tc_port_unlock(struct intel_digital_port *dig_port)
>   				      wakeref);
>   }
>   
> +/**
> + * intel_tc_port_disconnect_phy: disconnect TypeC PHY from display port
> + * @dig_port: digital port
> + *
> + * Disconnect the given digital port from its TypeC PHY (handing back the
> + * control of the PHY to the TypeC subsystem). The only purpose of this
> + * function is to force the disconnect even with a TypeC display output still
> + * plugged to the TypeC connector, which is required by the TypeC firmwares
> + * during system suspend and shutdown. Otherwise - during the unplug event
> + * handling - the PHY ownership is released automatically by
> + * intel_tc_port_reset_mode(), when calling this function is not required.
> + */
> +void intel_tc_port_disconnect_phy(struct intel_digital_port *dig_port)
> +{
> +	__intel_tc_port_lock(dig_port, 1, true);
> +	intel_tc_port_unlock(dig_port);
> +}
> +
>   bool intel_tc_port_ref_held(struct intel_digital_port *dig_port)
>   {
>   	return mutex_is_locked(&dig_port->tc_lock) ||
> @@ -604,7 +624,7 @@ bool intel_tc_port_ref_held(struct intel_digital_port *dig_port)
>   void intel_tc_port_get_link(struct intel_digital_port *dig_port,
>   			    int required_lanes)
>   {
> -	__intel_tc_port_lock(dig_port, required_lanes);
> +	__intel_tc_port_lock(dig_port, required_lanes, false);
>   	dig_port->tc_link_refcount++;
>   	intel_tc_port_unlock(dig_port);
>   }
> diff --git a/drivers/gpu/drm/i915/display/intel_tc.h b/drivers/gpu/drm/i915/display/intel_tc.h
> index b619e4736f85..57d157fc822f 100644
> --- a/drivers/gpu/drm/i915/display/intel_tc.h
> +++ b/drivers/gpu/drm/i915/display/intel_tc.h
> @@ -13,6 +13,8 @@ struct intel_digital_port;
>   struct intel_encoder;
>   
>   bool intel_tc_port_connected(struct intel_encoder *encoder);
> +void intel_tc_port_disconnect_phy(struct intel_digital_port *dig_port);
> +
>   u32 intel_tc_port_get_lane_mask(struct intel_digital_port *dig_port);
>   u32 intel_tc_port_get_pin_assignment_mask(struct intel_digital_port *dig_port);
>   int intel_tc_port_fia_max_lane_count(struct intel_digital_port *dig_port);
> 

-- 
-----------
Tim Gardner
Canonical, Inc



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