[Intel-gfx] [PATCH RESEND 7/7] drm/i915/mst: only ack the ESI we actually handled

[Jani Nikula]

On Thu, 20 Jan 2022, "Shankar, Uma" <uma.shankar at intel.com> wrote:
>> -----Original Message-----
>> From: Intel-gfx <intel-gfx-bounces at lists.freedesktop.org> On Behalf Of Jani Nikula
>> Sent: Wednesday, January 12, 2022 4:33 PM
>> To: intel-gfx at lists.freedesktop.org
>> Cc: Nikula, Jani <jani.nikula at intel.com>
>> Subject: [Intel-gfx] [PATCH RESEND 7/7] drm/i915/mst: only ack the ESI we actually
>> handled
>> 
>> Seems odd that we clear all event status indicators if we've only handled some. Only
>> clear the ones we've handled.
>
> Looks Good to me.
> Reviewed-by: Uma Shankar <uma.shankar at intel.com>

Thanks, please also see v2 of this patch I accidentally posted to the
old thread first. I guess you were replying to two threads too. :)

BR,
Jani

>
>> Signed-off-by: Jani Nikula <jani.nikula at intel.com>
>> ---
>>  drivers/gpu/drm/i915/display/intel_dp.c | 20 ++++++++++++--------
>>  1 file changed, 12 insertions(+), 8 deletions(-)
>> 
>> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c
>> b/drivers/gpu/drm/i915/display/intel_dp.c
>> index 95e9f7220ab8..548419a4ead8 100644
>> --- a/drivers/gpu/drm/i915/display/intel_dp.c
>> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
>> @@ -3625,13 +3625,17 @@ static void intel_dp_handle_test_request(struct
>> intel_dp *intel_dp)  }
>> 
>>  static void
>> -intel_dp_mst_hpd_irq(struct intel_dp *intel_dp, u8 *esi, bool *handled)
>> +intel_dp_mst_hpd_irq(struct intel_dp *intel_dp, u8 *esi, u8 *ack)
>>  {
>> -	drm_dp_mst_hpd_irq(&intel_dp->mst_mgr, esi, handled);
>> +	bool handled = false;
>> +
>> +	drm_dp_mst_hpd_irq(&intel_dp->mst_mgr, esi, &handled);
>> +	if (handled)
>> +		ack[1] |= DP_DOWN_REP_MSG_RDY | DP_UP_REQ_MSG_RDY;
>> 
>>  	if (esi[1] & DP_CP_IRQ) {
>>  		intel_hdcp_handle_cp_irq(intel_dp->attached_connector);
>> -		*handled = true;
>> +		ack[1] |= DP_CP_IRQ;
>>  	}
>>  }
>> 
>> @@ -3683,7 +3687,7 @@ intel_dp_check_mst_status(struct intel_dp *intel_dp)
>> 
>>  	for (;;) {
>>  		u8 esi[4] = {};
>> -		bool handled;
>> +		u8 ack[4] = {};
>> 
>>  		if (!intel_dp_get_sink_irq_esi(intel_dp, esi)) {
>>  			drm_dbg_kms(&i915->drm,
>> @@ -3699,15 +3703,15 @@ intel_dp_check_mst_status(struct intel_dp *intel_dp)
>>  		    esi[3] & LINK_STATUS_CHANGED) {
>>  			if (!intel_dp_mst_link_status(intel_dp))
>>  				link_ok = false;
>> -			handled = true;
>> +			ack[3] |= LINK_STATUS_CHANGED;
>>  		}
>> 
>> -		intel_dp_mst_hpd_irq(intel_dp, esi, &handled);
>> +		intel_dp_mst_hpd_irq(intel_dp, esi, ack);
>> 
>> -		if (!handled)
>> +		if (!memchr_inv(ack, 0, sizeof(ack)))
>>  			break;
>> 
>> -		if (!intel_dp_ack_sink_irq_esi(intel_dp, esi))
>> +		if (!intel_dp_ack_sink_irq_esi(intel_dp, ack))
>>  			drm_dbg_kms(&i915->drm, "Failed to ack ESI\n");
>>  	}
>> 
>> --
>> 2.30.2
>

-- 
Jani Nikula, Intel Open Source Graphics Center