[PATCH v2 09/14] drm/i915: add config function for YCBCR420 outputs

[Sharma, Shashank]

Regards

Shashank


On 7/15/2017 12:00 AM, Ville Syrjälä wrote:
> On Thu, Jul 13, 2017 at 09:03:15PM +0530, Shashank Sharma wrote:
>> This patch checks encoder level support for YCBCR420 outputs.
>> The logic goes as simple as this:
>> If the input mode is YCBCR420-only mode: prepare HDMI for
>> YCBCR420 output, else continue with RGB output mode.
>>
>> It checks if the mode is YCBCR420 and source can support this
>> output then it marks the ycbcr_420 output indicator into crtc
>> state, for further staging in driver.
>>
>> V2: Split the patch into two, kept helper functions in DRM layer.
>> V3: Changed the compute_config function based on new DRM API.
>> V4: Rebase
>> V5: Rebase
>> V6: Check and handle YCBCR420-only modes, discard the property
>>      based approach (Ville)
>> V7: Addressed review comments from Ville
>>      - add else case in 12BPC check.
>>      - extract ycbcr420 state inside hdmi_12bpc_possible function.
>>
>> Cc: Ville Syrjala <ville.syrjala at linux.intel.com>
>> Cc: Daniel Vetter <daniel.vetter at intel.com>
>> Cc: Ander Conselvan de Oliveira <conselvan2 at gmail.com>
>>
>> Signed-off-by: Shashank Sharma <shashank.sharma at intel.com>
>> ---
>>   drivers/gpu/drm/i915/intel_display.c |  1 +
>>   drivers/gpu/drm/i915/intel_drv.h     |  3 +++
>>   drivers/gpu/drm/i915/intel_hdmi.c    | 43 +++++++++++++++++++++++++++++++++---
>>   3 files changed, 44 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
>> index 2144adc..a5140e4 100644
>> --- a/drivers/gpu/drm/i915/intel_display.c
>> +++ b/drivers/gpu/drm/i915/intel_display.c
>> @@ -11945,6 +11945,7 @@ intel_pipe_config_compare(struct drm_i915_private *dev_priv,
>>   	PIPE_CONF_CHECK_I(hdmi_scrambling);
>>   	PIPE_CONF_CHECK_I(hdmi_high_tmds_clock_ratio);
>>   	PIPE_CONF_CHECK_I(has_infoframe);
>> +	PIPE_CONF_CHECK_I(ycbcr420);
>>   
>>   	PIPE_CONF_CHECK_I(has_audio);
>>   
>> diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
>> index d17a324..592243b 100644
>> --- a/drivers/gpu/drm/i915/intel_drv.h
>> +++ b/drivers/gpu/drm/i915/intel_drv.h
>> @@ -780,6 +780,9 @@ struct intel_crtc_state {
>>   
>>   	/* HDMI High TMDS char rate ratio */
>>   	bool hdmi_high_tmds_clock_ratio;
>> +
>> +	/* HDMI output type */
> We'll want DP too at some point. So that's going to get stale pretty
> soon.
Agree, will make it output format ycbcr420
>> +	bool ycbcr420;
>>   };
>>   
>>   struct intel_crtc {
>> diff --git a/drivers/gpu/drm/i915/intel_hdmi.c b/drivers/gpu/drm/i915/intel_hdmi.c
>> index cc0d100..eb6243c 100644
>> --- a/drivers/gpu/drm/i915/intel_hdmi.c
>> +++ b/drivers/gpu/drm/i915/intel_hdmi.c
>> @@ -1312,6 +1312,7 @@ static bool hdmi_12bpc_possible(struct intel_crtc_state *crtc_state)
>>   	struct drm_atomic_state *state = crtc_state->base.state;
>>   	struct drm_connector_state *connector_state;
>>   	struct drm_connector *connector;
>> +	bool output_ycbcr420 = crtc_state->ycbcr420;
> Pointless variable. Just use 'crtc_state->ycbcr420' in the code
> directly.
Ah, yes it was used at more places before we removed some of the code, 
during review.
Sure, will use that directly.
>>   	int i;
>>   
>>   	if (HAS_GMCH_DISPLAY(dev_priv))
>> @@ -1330,8 +1331,16 @@ static bool hdmi_12bpc_possible(struct intel_crtc_state *crtc_state)
>>   		if (connector_state->crtc != crtc_state->base.crtc)
>>   			continue;
>>   
>> -		if ((info->edid_hdmi_dc_modes & DRM_EDID_HDMI_DC_36) == 0)
>> -			return false;
>> +		if (output_ycbcr420) {
>> +			const struct drm_hdmi_info *hdmi = &info->hdmi;
>> +
>> +			if (!(hdmi->y420_dc_modes & DRM_EDID_YCBCR420_DC_36))
>> +				return false;
>> +		} else {
>> +
> Bogus whitespace.
Got it.
>> +			if (!(info->edid_hdmi_dc_modes & DRM_EDID_HDMI_DC_36))
>> +				return false;
>> +		}
>>   	}
>>   
>>   	/* Display Wa #1139 */
>> @@ -1342,6 +1351,25 @@ static bool hdmi_12bpc_possible(struct intel_crtc_state *crtc_state)
>>   	return true;
>>   }
>>   
>> +static bool
>> +intel_hdmi_ycbcr420_config(struct drm_connector *connector,
>> +			       struct intel_crtc_state *config,
>> +			       int *clock_12bpc, int *clock_8bpc)
>> +{
>> +
> Bogus whitespace.
Got it.

- Shashank
>> +	if (!connector->ycbcr_420_allowed) {
>> +		DRM_ERROR("Platform doesn't support YCBCR420 output\n");
>> +		return false;
>> +	}
>> +
>> +	/* YCBCR420 TMDS rate requirement is half the pixel clock */
>> +	config->port_clock /= 2;
>> +	*clock_12bpc /= 2;
>> +	*clock_8bpc /= 2;
>> +	config->ycbcr420 = true;
>> +	return true;
>> +}
>> +
>>   bool intel_hdmi_compute_config(struct intel_encoder *encoder,
>>   			       struct intel_crtc_state *pipe_config,
>>   			       struct drm_connector_state *conn_state)
>> @@ -1349,7 +1377,8 @@ bool intel_hdmi_compute_config(struct intel_encoder *encoder,
>>   	struct intel_hdmi *intel_hdmi = enc_to_intel_hdmi(&encoder->base);
>>   	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
>>   	struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode;
>> -	struct drm_scdc *scdc = &conn_state->connector->display_info.hdmi.scdc;
>> +	struct drm_connector *connector = conn_state->connector;
>> +	struct drm_scdc *scdc = &connector->display_info.hdmi.scdc;
>>   	struct intel_digital_connector_state *intel_conn_state =
>>   		to_intel_digital_connector_state(conn_state);
>>   	int clock_8bpc = pipe_config->base.adjusted_mode.crtc_clock;
>> @@ -1379,6 +1408,14 @@ bool intel_hdmi_compute_config(struct intel_encoder *encoder,
>>   		clock_12bpc *= 2;
>>   	}
>>   
>> +	if (drm_mode_is_420_only(&connector->display_info, adjusted_mode)) {
>> +		if (!intel_hdmi_ycbcr420_config(connector, pipe_config,
>> +						&clock_12bpc, &clock_8bpc)) {
>> +			DRM_ERROR("Can't support YCBCR420 output\n");
>> +			return false;
>> +		}
>> +	}
>> +
>>   	if (HAS_PCH_SPLIT(dev_priv) && !HAS_DDI(dev_priv))
>>   		pipe_config->has_pch_encoder = true;
>>   
>> -- 
>> 2.7.4