[PATCH v2 3/9] drm/i915/dp: Move vswing/pre-emphasis adjustment calculation

Manna, Animesh animesh.manna at intel.com
Thu Dec 19 13:31:22 UTC 2019


On 19-12-2019 18:03, Ville Syrjälä wrote:
> On Wed, Dec 18, 2019 at 08:43:44PM +0530, Animesh Manna wrote:
>> vswing/pre-emphasis adjustment calculation is needed in processing
>> of auto phy compliance request other than link training, so moved
>> the same function in intel_dp.c.
>>
>> No functional change.
>>
>> Signed-off-by: Animesh Manna <animesh.manna at intel.com>
>> ---
>>   drivers/gpu/drm/i915/display/intel_dp.c       | 32 +++++++++++++++++++
>>   drivers/gpu/drm/i915/display/intel_dp.h       |  3 ++
>>   .../drm/i915/display/intel_dp_link_training.c | 32 -------------------
>>   3 files changed, 35 insertions(+), 32 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
>> index 2f31d226c6eb..ca82835b6dcf 100644
>> --- a/drivers/gpu/drm/i915/display/intel_dp.c
>> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
>> @@ -4110,6 +4110,38 @@ ivb_cpu_edp_signal_levels(u8 train_set)
>>   	}
>>   }
>>   
>> +void
>> +intel_get_adjust_train(struct intel_dp *intel_dp,
>> +		       const u8 *link_status)
> I'd prefer to keep the arrayish notation so we have some idea how big
> this is supposed to be. I guess that woukld mean including some
> drm dp header in intel_dp.h?

Yes, will add.

Regards,
Animesh

>
>> +{
>> +	u8 v = 0;
>> +	u8 p = 0;
>> +	int lane;
>> +	u8 voltage_max;
>> +	u8 preemph_max;
>> +
>> +	for (lane = 0; lane < intel_dp->lane_count; lane++) {
>> +		u8 this_v = drm_dp_get_adjust_request_voltage(link_status, lane);
>> +		u8 this_p = drm_dp_get_adjust_request_pre_emphasis(link_status, lane);
>> +
>> +		if (this_v > v)
>> +			v = this_v;
>> +		if (this_p > p)
>> +			p = this_p;
>> +	}
>> +
>> +	voltage_max = intel_dp_voltage_max(intel_dp);
>> +	if (v >= voltage_max)
>> +		v = voltage_max | DP_TRAIN_MAX_SWING_REACHED;
>> +
>> +	preemph_max = intel_dp_pre_emphasis_max(intel_dp, v);
>> +	if (p >= preemph_max)
>> +		p = preemph_max | DP_TRAIN_MAX_PRE_EMPHASIS_REACHED;
>> +
>> +	for (lane = 0; lane < 4; lane++)
>> +		intel_dp->train_set[lane] = v | p;
>> +}
>> +
>>   void
>>   intel_dp_set_signal_levels(struct intel_dp *intel_dp)
>>   {
>> diff --git a/drivers/gpu/drm/i915/display/intel_dp.h b/drivers/gpu/drm/i915/display/intel_dp.h
>> index 3da166054788..0d0cb692f701 100644
>> --- a/drivers/gpu/drm/i915/display/intel_dp.h
>> +++ b/drivers/gpu/drm/i915/display/intel_dp.h
>> @@ -91,6 +91,9 @@ void
>>   intel_dp_program_link_training_pattern(struct intel_dp *intel_dp,
>>   				       u8 dp_train_pat);
>>   void
>> +intel_get_adjust_train(struct intel_dp *intel_dp,
>> +		       const u8 *link_status);
>> +void
>>   intel_dp_set_signal_levels(struct intel_dp *intel_dp);
>>   void intel_dp_set_idle_link_train(struct intel_dp *intel_dp);
>>   u8
>> diff --git a/drivers/gpu/drm/i915/display/intel_dp_link_training.c b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
>> index 2a1130dd1ad0..1e38584e7d56 100644
>> --- a/drivers/gpu/drm/i915/display/intel_dp_link_training.c
>> +++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
>> @@ -34,38 +34,6 @@ intel_dp_dump_link_status(const u8 link_status[DP_LINK_STATUS_SIZE])
>>   		      link_status[3], link_status[4], link_status[5]);
>>   }
>>   
>> -static void
>> -intel_get_adjust_train(struct intel_dp *intel_dp,
>> -		       const u8 link_status[DP_LINK_STATUS_SIZE])
>> -{
>> -	u8 v = 0;
>> -	u8 p = 0;
>> -	int lane;
>> -	u8 voltage_max;
>> -	u8 preemph_max;
>> -
>> -	for (lane = 0; lane < intel_dp->lane_count; lane++) {
>> -		u8 this_v = drm_dp_get_adjust_request_voltage(link_status, lane);
>> -		u8 this_p = drm_dp_get_adjust_request_pre_emphasis(link_status, lane);
>> -
>> -		if (this_v > v)
>> -			v = this_v;
>> -		if (this_p > p)
>> -			p = this_p;
>> -	}
>> -
>> -	voltage_max = intel_dp_voltage_max(intel_dp);
>> -	if (v >= voltage_max)
>> -		v = voltage_max | DP_TRAIN_MAX_SWING_REACHED;
>> -
>> -	preemph_max = intel_dp_pre_emphasis_max(intel_dp, v);
>> -	if (p >= preemph_max)
>> -		p = preemph_max | DP_TRAIN_MAX_PRE_EMPHASIS_REACHED;
>> -
>> -	for (lane = 0; lane < 4; lane++)
>> -		intel_dp->train_set[lane] = v | p;
>> -}
>> -
>>   static bool
>>   intel_dp_set_link_train(struct intel_dp *intel_dp,
>>   			u8 dp_train_pat)
>> -- 
>> 2.24.0


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