[PATCH 20/20] drm/i915/dp: Ack only the handled link service IRQs

[Luca Coelho]

On Thu, 2025-06-26 at 11:20 +0300, Imre Deak wrote:
> From: Imre Deak <imre.deak at gmail.com>
> 
> Ack only those SST link service IRQs that will be handled, similarly to
> device service IRQs. While at it add asserts that only the known/acked
> link service IRQs are handled both in the MST and SST case.
> 
> Signed-off-by: Imre Deak <imre.deak at gmail.com>
> ---
>  drivers/gpu/drm/i915/display/intel_dp.c | 17 ++++++++++++++++-
>  1 file changed, 16 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
> index 6f67fac9724e1..0e3e9ab3ac604 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> @@ -4545,6 +4545,16 @@ intel_dp_mst_disconnect(struct intel_dp *intel_dp)
>  						 DP_DOWN_REP_MSG_RDY | \
>  						 DP_UP_REQ_MSG_RDY)
>  
> +#define INTEL_DP_LINK_SERVICE_IRQ_MASK_SST	(RX_CAP_CHANGED | \
> +						 LINK_STATUS_CHANGED | \
> +						 HDMI_LINK_STATUS_CHANGED | \
> +						 CONNECTED_OFF_ENTRY_REQUESTED | \
> +						 DP_TUNNELING_IRQ)
> +
> +#define INTEL_DP_LINK_SERVICE_IRQ_MASK_MST	(RX_CAP_CHANGED | \
> +						 LINK_STATUS_CHANGED | \
> +						 DP_TUNNELING_IRQ)
> +
>  static bool
>  intel_dp_get_sink_irq_esi(struct intel_dp *intel_dp, u8 *esi)
>  {
> @@ -4637,6 +4647,7 @@ static bool intel_dp_get_and_ack_sink_irq_esi_sst(struct intel_dp *intel_dp, u8
>  		    esi);
>  
>  	esi[1] &= INTEL_DP_DEVICE_SERVICE_IRQ_MASK_SST;
> +	esi[3] &= INTEL_DP_LINK_SERVICE_IRQ_MASK_SST;
>  
>  	if (mem_is_zero(&esi[1], 3))
>  		return true;
> @@ -5175,7 +5186,7 @@ intel_dp_check_mst_status(struct intel_dp *intel_dp)
>  
>  		drm_dbg_kms(display->drm, "DPRX ESI: %4ph\n", esi);
>  
> -		ack[3] |= esi[3] & (RX_CAP_CHANGED | LINK_STATUS_CHANGED | DP_TUNNELING_IRQ);
> +		ack[3] |= esi[3] & INTEL_DP_LINK_SERVICE_IRQ_MASK_MST;
>  
>  		intel_dp_mst_hpd_irq(intel_dp, esi, ack);
>  
> @@ -5183,6 +5194,7 @@ intel_dp_check_mst_status(struct intel_dp *intel_dp)
>  			break;
>  
>  		drm_WARN_ON(display->drm, ack[1] & ~INTEL_DP_DEVICE_SERVICE_IRQ_MASK_MST);
> +		drm_WARN_ON(display->drm, ack[3] & ~INTEL_DP_LINK_SERVICE_IRQ_MASK_MST);
>  
>  		if (!intel_dp_ack_sink_irq_esi(intel_dp, ack))
>  			drm_dbg_kms(display->drm, "Failed to ack ESI\n");
> @@ -5487,6 +5499,9 @@ static bool intel_dp_handle_link_service_irq(struct intel_dp *intel_dp, u8 irq_m
>  	struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;
>  	bool reprobe_needed = false;
>  
> +	drm_WARN_ON(display->drm, irq_mask & ~(INTEL_DP_LINK_SERVICE_IRQ_MASK_SST |
> +					       INTEL_DP_LINK_SERVICE_IRQ_MASK_MST));
> +
>  	if (irq_mask & RX_CAP_CHANGED)
>  		reprobe_needed = true;
>  

Okay, so for link service, this is function also handles MST stuff. 
So, maybe for consistency, you can ignore my comment about adding
"_sst" in the previous patch.

Reviewed-by: Luca Coelho <luciano.coelho at intel.com>

--
Cheers,
Luca.