[Intel-gfx] [PATCH v4 10/15] drm/i915: add compute-config for YCBCR outputs
Sharma, Shashank
shashank.sharma at intel.com
Wed Jun 21 15:49:04 UTC 2017
Regards
Shashank
On 6/20/2017 7:50 PM, Ander Conselvan De Oliveira wrote:
> On Mon, 2017-06-19 at 21:38 +0530, Shashank Sharma wrote:
>> This patch checks encoder level support for HDMI YCBCR outputs.
>> HDMI output mode is a connector property, this patch checks if
>> source and sink can support the HDMI output type selected by user.
>> And if they both can, it commits the hdmi output type 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
>>
>> Cc: Ville Syrjala <ville.syrjala at linux.intel.com>
>> Cc: Daniel Vetter <daniel.vetter at intel.com>
>> Cc: Ander Conselvan De Oliveira <ander.conselvan.de.oliveira at intel.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 | 93 ++++++++++++++++++++++++++++++++++--
>> 3 files changed, 94 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
>> index f9bf0d5..da29536 100644
>> --- a/drivers/gpu/drm/i915/intel_display.c
>> +++ b/drivers/gpu/drm/i915/intel_display.c
>> @@ -11930,6 +11930,7 @@ 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(hdmi_output);
>>
>> 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 1727350..38fe56c 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 */
>> + enum drm_hdmi_output_type hdmi_output;
>> };
>>
>> struct intel_crtc {
>> diff --git a/drivers/gpu/drm/i915/intel_hdmi.c b/drivers/gpu/drm/i915/intel_hdmi.c
>> index 170abc4..22da5cd 100644
>> --- a/drivers/gpu/drm/i915/intel_hdmi.c
>> +++ b/drivers/gpu/drm/i915/intel_hdmi.c
>> @@ -1317,7 +1317,8 @@ intel_hdmi_mode_valid(struct drm_connector *connector,
>> return status;
>> }
>>
>> -static bool hdmi_12bpc_possible(struct intel_crtc_state *crtc_state)
>> +static bool hdmi_12bpc_possible(struct intel_crtc_state *crtc_state,
>> + enum drm_hdmi_output_type hdmi_out)
>> {
>> struct drm_i915_private *dev_priv =
>> to_i915(crtc_state->base.crtc->dev);
>> @@ -1329,6 +1330,16 @@ static bool hdmi_12bpc_possible(struct intel_crtc_state *crtc_state)
>> if (HAS_GMCH_DISPLAY(dev_priv))
>> return false;
>>
>> + if (hdmi_out == DRM_HDMI_OUTPUT_YCBCR422) {
>> + /*
>> + * HDMI spec says YCBCR422 is 12bpc, but its not a deep
>> + * color format. So respect the spec, and not allow this
>> + * to be deep color
>> + */
>> + DRM_DEBUG_KMS("Not allowing deep color for YCBCR422 output\n");
>> + return false;
>> + }
>> +
> I suppose this is about the remark in section 6.2.4 of the HDMI 1.4 spec. If I'm
> interpreting that correctly, the relevant information for us is that the TMDS
> clock doesn't need to be multiplied by 1.5, unlike other 12 bpc scenarios.
>
> To me it seems misleading to say 12 bpc is not possible in that case. I'm
> wondering if it makes more sense to split this in two parts:
>
> (i) What is the TMDS clock scaling for a given output format?
> (ii) Is the format and scaled TMDS clock supported by the source and the sink?
My interpretation of the spec was YCBCR422 is a 12 bit encoding scheme,
but its not a deep color mode (I guess that's what Ville also thought)
In I915, 12_bpc is always considered as deep color mode case, whereas I
have seen EDIDs which indicate support for YCBCR422 but they do not
indicate deep color support.
Combining these information above, we thought its safe to consider that
422 is not a deep color mode, and hence this call.
>
>> /*
>> * HDMI 12bpc affects the clocks, so it's only possible
>> * when not cloning with other encoder types.
>> @@ -1342,6 +1353,12 @@ static bool hdmi_12bpc_possible(struct intel_crtc_state *crtc_state)
>> if (connector_state->crtc != crtc_state->base.crtc)
>> continue;
>>
>> + if (hdmi_out == DRM_HDMI_OUTPUT_YCBCR420) {
>> + if (!(info->hdmi.y420_dc_modes &
>> + DRM_EDID_YCBCR420_DC_36))
>> + return false;
>> + }
>> +
>> if ((info->edid_hdmi_dc_modes & DRM_EDID_HDMI_DC_36) == 0)
>> return false;
>> }
>> @@ -1354,6 +1371,65 @@ static bool hdmi_12bpc_possible(struct intel_crtc_state *crtc_state)
>> return true;
>> }
>>
>> +static u8
>> +intel_hdmi_get_src_output_support(struct drm_connector *connector)
>> +{
>> + struct drm_i915_private *dev_priv = connector->dev->dev_private;
>> + u8 supported_outputs = DRM_COLOR_FORMAT_RGB444;
>> +
>> + if (dev_priv->info.gen < 7)
>> + return supported_outputs;
>> +
>> + /* Gen 7 and above support HDMI 1.4b outputs */
>> + supported_outputs |= (DRM_COLOR_FORMAT_YCRCB444 |
>> + DRM_COLOR_FORMAT_YCRCB422);
>> +
>> + if (IS_GEMINILAKE(dev_priv))
>> + supported_outputs |= DRM_COLOR_FORMAT_YCRCB420;
>> +
>> + return supported_outputs;
>> +}
>> +
>> +static enum drm_hdmi_output_type
>> +intel_hdmi_compute_ycbcr_config(struct drm_connector_state *conn_state,
>> + struct intel_crtc_state *config,
>> + int *clock_12bpc, int *clock_8bpc)
>> +{
>> + struct drm_connector *connector = conn_state->connector;
>> + struct drm_display_mode *mode = &config->base.adjusted_mode;
>> + enum drm_hdmi_output_type type = conn_state->hdmi_output;
>> + u8 src_output_cap = intel_hdmi_get_src_output_support(connector);
>> +
>> + /*
>> + * Can we support any YCBCR output based on these parameters ?
>> + * current source capabilities +
>> + * current sink capabilities +
>> + * given video mode +
>> + * current user's choice for HDMI output (from connector property)
>> + */
>> + type = drm_find_hdmi_output_type(connector, mode, type, src_output_cap);
>> + if ((type == DRM_HDMI_OUTPUT_INVALID) ||
> Unnecessary parenthesis.
Got it
>
>> + (type == DRM_HDMI_OUTPUT_DEFAULT_RGB)) {
> Ditto, plus wrong indentation.
Got it
>
>> + DRM_DEBUG_KMS("Can't support YCBCR output\n");
>> + return type;
>> + }
>> +
>> + if (type == DRM_HDMI_OUTPUT_YCBCR420) {
>> +
>> + /* YCBCR420 TMDS rate requirement is half the pixel clock */
>> + config->hdmi_output = DRM_HDMI_OUTPUT_YCBCR420;
>> + config->port_clock /= 2;
>> + *clock_12bpc /= 2;
>> + *clock_8bpc /= 2;
>> +
>> + }
> I think with the idea I described above, this could be done in in
> intel_hdmi_comput_config().
Might need more discussion on idea above.
>> +
>> + /* Encoder is capable of this output, lets commit to CRTC */
>> + config->hdmi_output = type;
>> + DRM_DEBUG_KMS("HDMI output: %s\n", drm_get_hdmi_output_name(type));
>> + return type;
> Couldn't this function just return true or false? The value is returned by
> editing config->hdmi_output. Not a big fan of having DRM_HDMI_OUTPUT_INVALID to
> mean that something failed.
Sure, Can do that, Its easier to pass the value coming from lower
function, thats why chose current return type :-)
> Ander
>
>> +}
>> +
>> bool intel_hdmi_compute_config(struct intel_encoder *encoder,
>> struct intel_crtc_state *pipe_config,
>> struct drm_connector_state *conn_state)
>> @@ -1361,13 +1437,15 @@ 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;
>> int clock_12bpc = clock_8bpc * 3 / 2;
>> int desired_bpp;
>> bool force_dvi = intel_conn_state->force_audio == HDMI_AUDIO_OFF_DVI;
>> + enum drm_hdmi_output_type hdmi_out = conn_state->hdmi_output;
>>
>> pipe_config->has_hdmi_sink = !force_dvi && intel_hdmi->has_hdmi_sink;
>>
>> @@ -1391,6 +1469,15 @@ bool intel_hdmi_compute_config(struct intel_encoder *encoder,
>> clock_12bpc *= 2;
>> }
>>
>> + /* Check if YCBCR HDMI output handling is required */
>> + hdmi_out = intel_hdmi_compute_ycbcr_config(conn_state,
>> + pipe_config, &clock_12bpc,
>> + &clock_8bpc);
>> + if (hdmi_out == DRM_HDMI_OUTPUT_INVALID) {
>> + DRM_ERROR("Can't support desired HDMI output\n");
>> + return false;
>> + }
>> +
>> if (HAS_PCH_SPLIT(dev_priv) && !HAS_DDI(dev_priv))
>> pipe_config->has_pch_encoder = true;
>>
>> @@ -1410,7 +1497,7 @@ bool intel_hdmi_compute_config(struct intel_encoder *encoder,
>> */
>> if (pipe_config->pipe_bpp > 8*3 && pipe_config->has_hdmi_sink && !force_dvi &&
>> hdmi_port_clock_valid(intel_hdmi, clock_12bpc, true, force_dvi) == MODE_OK &&
>> - hdmi_12bpc_possible(pipe_config)) {
>> + hdmi_12bpc_possible(pipe_config, hdmi_out)) {
>> DRM_DEBUG_KMS("picking bpc to 12 for HDMI output\n");
>> desired_bpp = 12*3;
>>
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