[PATCH v2 17/21] drm/i915/dp: Handle DP tunnel IRQs

[Shankar, Uma]

> -----Original Message-----
> From: Intel-gfx <intel-gfx-bounces at lists.freedesktop.org> On Behalf Of Imre
> Deak
> Sent: Wednesday, February 21, 2024 2:49 AM
> To: intel-gfx at lists.freedesktop.org; dri-devel at lists.freedesktop.org
> Subject: [PATCH v2 17/21] drm/i915/dp: Handle DP tunnel IRQs
> 
> Handle DP tunnel IRQs a sink (or rather a BW management component like the
> Thunderbolt Connection Manager) raises to signal the completion of a BW
> request by the driver, or to signal any state change related to the link BW.

Looks Good to me.
Reviewed-by: Uma Shankar <uma.shankar at intel.com>
X`
> Signed-off-by: Imre Deak <imre.deak at intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_dp.c | 37 +++++++++++++++++++------
>  include/drm/display/drm_dp.h            |  1 +
>  2 files changed, 29 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c
> b/drivers/gpu/drm/i915/display/intel_dp.c
> index 5ad7808788745..a3dfcbb710027 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> @@ -4904,13 +4904,15 @@ static bool intel_dp_mst_link_status(struct intel_dp
> *intel_dp)
>   * - %true if pending interrupts were serviced (or no interrupts were
>   *   pending) w/o detecting an error condition.
>   * - %false if an error condition - like AUX failure or a loss of link - is
> - *   detected, which needs servicing from the hotplug work.
> + *   detected, or another condition - like a DP tunnel BW state change - needs
> + *   servicing from the hotplug work.
>   */
>  static bool
>  intel_dp_check_mst_status(struct intel_dp *intel_dp)  {
>  	struct drm_i915_private *i915 = dp_to_i915(intel_dp);
>  	bool link_ok = true;
> +	bool reprobe_needed = false;
> 
>  	drm_WARN_ON_ONCE(&i915->drm, intel_dp->active_mst_links < 0);
> 
> @@ -4937,6 +4939,13 @@ intel_dp_check_mst_status(struct intel_dp *intel_dp)
> 
>  		intel_dp_mst_hpd_irq(intel_dp, esi, ack);
> 
> +		if (esi[3] & DP_TUNNELING_IRQ) {
> +			if (drm_dp_tunnel_handle_irq(i915-
> >display.dp_tunnel_mgr,
> +						     &intel_dp->aux))
> +				reprobe_needed = true;
> +			ack[3] |= DP_TUNNELING_IRQ;
> +		}
> +
>  		if (!memchr_inv(ack, 0, sizeof(ack)))
>  			break;
> 
> @@ -4947,7 +4956,7 @@ intel_dp_check_mst_status(struct intel_dp *intel_dp)
>  			drm_dp_mst_hpd_irq_send_new_request(&intel_dp-
> >mst_mgr);
>  	}
> 
> -	return link_ok;
> +	return link_ok && !reprobe_needed;
>  }
> 
>  static void
> @@ -5304,23 +5313,32 @@ static void
> intel_dp_check_device_service_irq(struct intel_dp *intel_dp)
>  		drm_dbg_kms(&i915->drm, "Sink specific irq unhandled\n");  }
> 
> -static void intel_dp_check_link_service_irq(struct intel_dp *intel_dp)
> +static bool intel_dp_check_link_service_irq(struct intel_dp *intel_dp)
>  {
> +	struct drm_i915_private *i915 = dp_to_i915(intel_dp);
> +	bool reprobe_needed = false;
>  	u8 val;
> 
>  	if (intel_dp->dpcd[DP_DPCD_REV] < 0x11)
> -		return;
> +		return false;
> 
>  	if (drm_dp_dpcd_readb(&intel_dp->aux,
>  			      DP_LINK_SERVICE_IRQ_VECTOR_ESI0, &val) != 1 ||
> !val)
> -		return;
> +		return false;
> +
> +	if ((val & DP_TUNNELING_IRQ) &&
> +	    drm_dp_tunnel_handle_irq(i915->display.dp_tunnel_mgr,
> +				     &intel_dp->aux))
> +		reprobe_needed = true;
> 
>  	if (drm_dp_dpcd_writeb(&intel_dp->aux,
>  			       DP_LINK_SERVICE_IRQ_VECTOR_ESI0, val) != 1)
> -		return;
> +		return reprobe_needed;
> 
>  	if (val & HDMI_LINK_STATUS_CHANGED)
>  		intel_dp_handle_hdmi_link_status_change(intel_dp);
> +
> +	return reprobe_needed;
>  }
> 
>  /*
> @@ -5341,6 +5359,7 @@ intel_dp_short_pulse(struct intel_dp *intel_dp)  {
>  	struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
>  	u8 old_sink_count = intel_dp->sink_count;
> +	bool reprobe_needed = false;
>  	bool ret;
> 
>  	/*
> @@ -5363,7 +5382,7 @@ intel_dp_short_pulse(struct intel_dp *intel_dp)
>  	}
> 
>  	intel_dp_check_device_service_irq(intel_dp);
> -	intel_dp_check_link_service_irq(intel_dp);
> +	reprobe_needed = intel_dp_check_link_service_irq(intel_dp);
> 
>  	/* Handle CEC interrupts, if any */
>  	drm_dp_cec_irq(&intel_dp->aux);
> @@ -5390,10 +5409,10 @@ intel_dp_short_pulse(struct intel_dp *intel_dp)
>  		 * FIXME get rid of the ad-hoc phy test modeset code
>  		 * and properly incorporate it into the normal modeset.
>  		 */
> -		return false;
> +		reprobe_needed = true;
>  	}
> 
> -	return true;
> +	return !reprobe_needed;
>  }
> 
>  /* XXX this is probably wrong for multiple downstream ports */ diff --git
> a/include/drm/display/drm_dp.h b/include/drm/display/drm_dp.h index
> 8bfd5d007be8d..4891bd916d26a 100644
> --- a/include/drm/display/drm_dp.h
> +++ b/include/drm/display/drm_dp.h
> @@ -1081,6 +1081,7 @@
>  # define STREAM_STATUS_CHANGED               (1 << 2)
>  # define HDMI_LINK_STATUS_CHANGED            (1 << 3)
>  # define CONNECTED_OFF_ENTRY_REQUESTED       (1 << 4)
> +# define DP_TUNNELING_IRQ                    (1 << 5)
> 
>  #define DP_PSR_ERROR_STATUS                 0x2006  /* XXX 1.2? */
>  # define DP_PSR_LINK_CRC_ERROR              (1 << 0)
> --
> 2.39.2