[Intel-gfx] [RFC 1/6] drm/dp: get/set phy compliance pattern.

[Animesh Manna]

On 10/22/2019 4:57 AM, Manasi Navare wrote:
> On Thu, Oct 03, 2019 at 08:36:48PM +0530, Animesh Manna wrote:
>> During phy complaince auto test mode source need to read
>> requested test pattern from sink through DPCD. After processing
>> the request source need to set the pattern. So set/get method
>> added in drm layer as it is DP protocol.
>>
>> Signed-off-by: Animesh Manna <animesh.manna at intel.com>
>> ---
>>   drivers/gpu/drm/drm_dp_helper.c | 77 +++++++++++++++++++++++++++++++++
>>   include/drm/drm_dp_helper.h     | 28 ++++++++++++
>>   2 files changed, 105 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c
>> index f373798d82f6..3cb7170e55f4 100644
>> --- a/drivers/gpu/drm/drm_dp_helper.c
>> +++ b/drivers/gpu/drm/drm_dp_helper.c
>> @@ -1484,3 +1484,80 @@ int drm_dp_dsc_sink_supported_input_bpcs(const u8 dsc_dpcd[DP_DSC_RECEIVER_CAP_S
>>   	return num_bpc;
>>   }
>>   EXPORT_SYMBOL(drm_dp_dsc_sink_supported_input_bpcs);
>> +
>> +/**
>> + * drm_dp_get_phy_test_pattern() - get the requested pattern from the sink.
>> + * @aux: DisplayPort AUX channel
>> + * @data: DP phy compliance test parameters.
>> + *
>> + * Returns 0 on success or a negative error code on failure.
>> + */
>> +int drm_dp_get_phy_test_pattern(struct drm_dp_aux *aux,
>> +				struct drm_dp_phy_test_params *data)
>> +{
>> +	int err;
>> +
>> +	err = drm_dp_link_probe(aux, &data->link);
>> +	if (err < 0)
>> +		return err;
>> +
>> +	err = drm_dp_dpcd_read(aux, DP_TEST_PHY_PATTERN, &data->phy_pattern, 1);
> Just use drm_dp_dpcd_readb

Thanks Manasi for code review.
Will add all suggested changes here.

Regards,
Animesh
>
>> +	if (err < 0)
>> +		return err;
>> +
>> +	switch (data->phy_pattern) {
>> +	case DP_TEST_PHY_PATTERN_80BIT_CUSTOM:
>> +		err = drm_dp_dpcd_read(aux, DP_TEST_80BIT_CUSTOM_PATTERN_7_0,
>> +				       &data->custom80, 10);
>> +		if (err < 0)
>> +			return err;
>> +
>> +		break;
>> +	case DP_TEST_PHY_PATTERN_CP2520:
>> +		err = drm_dp_dpcd_read(aux, DP_TEST_HBR2_SCRAMBLER_RESET,
>> +				       &data->hbr2_reset, 2);
>> +		if (err < 0)
>> +			return err;
>> +	}
>> +
>> +	return 0;
>> +}
>> +EXPORT_SYMBOL(drm_dp_get_phy_test_pattern);
>> +
>> +/**
>> + * drm_dp_set_phy_test_pattern() - set the pattern to the sink.
>> + * @aux: DisplayPort AUX channel
>> + * @data: DP phy compliance test parameters.
>> + *
>> + * Returns 0 on success or a negative error code on failure.
>> + */
>> +int drm_dp_set_phy_test_pattern(struct drm_dp_aux *aux,
>> +				struct drm_dp_phy_test_params *data)
>> +{
>> +	int err, i;
>> +	u8 test_pattern;
>> +
>> +	err = drm_dp_link_configure(aux, &data->link);
>> +	if (err < 0)
>> +		return err;
>> +
>> +	test_pattern = data->phy_pattern;
>> +	if (data->link.revision < 0x12) {
>> +		test_pattern = (test_pattern << 2) &
>> +			       DP_LINK_QUAL_PATTERN_11_MASK;
>> +		err = drm_dp_dpcd_write(aux, DP_TRAINING_PATTERN_SET,
>> +					&test_pattern, 1);
> Same, just use drm_dp_dpcd_writeb
>
>> +		if (err < 0)
>> +			return err;
>> +	} else {
>> +		for (i = 0; i < data->link.num_lanes; i++) {
>> +			err = drm_dp_dpcd_write(aux, DP_LINK_QUAL_LANE0_SET + i,
>> +						&test_pattern, 1);
>> +			if (err < 0)
>> +				return err;
>> +		}
>> +	}
>> +
>> +	return 0;
>> +}
>> +EXPORT_SYMBOL(drm_dp_set_phy_test_pattern);
>> diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h
>> index ed1a985745ba..77dcf5879beb 100644
>> --- a/include/drm/drm_dp_helper.h
>> +++ b/include/drm/drm_dp_helper.h
>> @@ -691,6 +691,14 @@
>>   # define DP_TEST_COUNT_MASK		    0xf
>>   
>>   #define DP_TEST_PHY_PATTERN                 0x248
> This should be consistent with spec name DP_PHY_TEST_PATTERN
>
> And since the bits below are part of the 2:0 PATTERN_SEL, I would prefer
> having DP_PHY_TEST_PATTERN_SEL_MASK 0x7
>
>> +# define DP_TEST_PHY_PATTERN_NONE           0
>                                                 ^ 0x0
>> +# define DP_TEST_PHY_PATTERN_D10_2          1
>                                                 ^ 0x1 (to be consistent with other bit defs in .h file)
>
> Manasi
>
>> +# define DP_TEST_PHY_PATTERN_ERROR_COUNT    2
>> +# define DP_TEST_PHY_PATTERN_PRBS7          3
>> +# define DP_TEST_PHY_PATTERN_80BIT_CUSTOM   4
>> +# define DP_TEST_PHY_PATTERN_CP2520         5
>> +
>> +#define DP_TEST_HBR2_SCRAMBLER_RESET        0x24A
>>   #define DP_TEST_80BIT_CUSTOM_PATTERN_7_0    0x250
>>   #define	DP_TEST_80BIT_CUSTOM_PATTERN_15_8   0x251
>>   #define	DP_TEST_80BIT_CUSTOM_PATTERN_23_16  0x252
>> @@ -1523,4 +1531,24 @@ static inline void drm_dp_cec_unset_edid(struct drm_dp_aux *aux)
>>   
>>   #endif
>>   
>> +/**
>> + * struct drm_dp_phy_test_params - DP Phy Compliance parameters
>> + * @link: Link information.
>> + * @phy_pattern: DP Phy test pattern from DPCD 0x248 (sink)
>> + * @hb2_reset: DP HBR2_COMPLIANCE_SCRAMBLER_RESET from DCPD
>> + *            0x24A and 0x24B (sink)
>> + * @custom80: DP Test_80BIT_CUSTOM_PATTERN from DPCDs 0x250
>> + *               through 0x259.
>> + */
>> +struct drm_dp_phy_test_params {
>> +	struct drm_dp_link link;
>> +	u8 phy_pattern;
>> +	u8 hbr2_reset[2];
>> +	u8 custom80[10];
>> +};
>> +
>> +int drm_dp_get_phy_test_pattern(struct drm_dp_aux *aux,
>> +				struct drm_dp_phy_test_params *data);
>> +int drm_dp_set_phy_test_pattern(struct drm_dp_aux *aux,
>> +				struct drm_dp_phy_test_params *data);
>>   #endif /* _DRM_DP_HELPER_H_ */
>> -- 
>> 2.22.0
>>