[Intel-gfx] [PATCH v8 5/6] drm/i915: enable scrambling
Ville Syrjälä
ville.syrjala at linux.intel.com
Wed Mar 8 17:17:33 UTC 2017
On Wed, Mar 08, 2017 at 07:07:48PM +0530, Shashank Sharma wrote:
> Geminilake platform sports a native HDMI 2.0 controller, and is
> capable of driving pixel-clocks upto 594Mhz. HDMI 2.0 spec
> mendates scrambling for these higher clocks, for reduced RF footprint.
>
> This patch checks if the monitor supports scrambling, and if required,
> enables it during the modeset.
>
> V2: Addressed review comments from Ville:
> - Do not track scrambling status in DRM layer, track somewhere in
> driver like in intel_crtc_state.
> - Don't talk to monitor at such a low layer, set monitor scrambling
> in intel_enable_ddi() before enabling the port.
>
> V3: Addressed review comments from Jani
> - In comments, function names, use "sink" instead of "monitor",
> so that the implementation could be close to the language of
> HDMI spec.
>
> V4: Addressed review comment from Maarten
> - scrambling -> hdmi_scrambling
> - high_tmds_clock_ratio -> hdmi_high_tmds_clock_ratio
>
> V5: Addressed review comments from Ville and Ander
> - Do not modifiy the crtc_state after compute_config. Move all
> scrambling and tmds_clock_ratio calcutations to compute_config.
> - While setting scrambling for source/sink, do not check the
> conditions again, just go by the crtc_state flags. This will
> simplyfy the condition checks.
>
> V6: Addressed review comments from Ville
> - Do not add IS_GLK check in disable/enable function, instead add it
> in compute_config, while setting state flags.
> - Remove unnecessary paranthesis.
> - Simplyfy handle_sink_scrambling function as suggested.
> - Add readout code for scrambling status in get_ddi_config and add a
> check for the same in pipe_config_compare.
>
> V7: Addressed review comments from Ander/Ville
> - No separate function for source scrambling, make it inline
> - Align the last line of the macro TRANS_DDI_HDMI_SCRAMBLING_MASK
> - Do not add platform check while setting source scrambling
> - Use pipe_config instead of crtc->config to set sink scrambling
> - To readout scrambling status, Compare with SCRAMBLING_MASK
> not any of its bits
> - Remove platform check in intel_pipe_config_compare while checking
> scrambling status
>
> V8: Fixed mege conflict, Addressed review comments from Ander
> - Remove the desciption/comment about scrambling fom the caller, move
> it to the function
> - Move the IS_GLK check into scrambling function
> - Fix alignment
>
> Signed-off-by: Shashank Sharma <shashank.sharma at intel.com>
> ---
> drivers/gpu/drm/i915/i915_reg.h | 7 ++++
> drivers/gpu/drm/i915/intel_ddi.c | 19 +++++++++++
> drivers/gpu/drm/i915/intel_display.c | 3 ++
> drivers/gpu/drm/i915/intel_drv.h | 10 ++++++
> drivers/gpu/drm/i915/intel_hdmi.c | 62 ++++++++++++++++++++++++++++++++++++
> 5 files changed, 101 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
> index cc843f9..2d50fdc 100644
> --- a/drivers/gpu/drm/i915/i915_reg.h
> +++ b/drivers/gpu/drm/i915/i915_reg.h
> @@ -7830,7 +7830,14 @@ enum {
> #define TRANS_DDI_EDP_INPUT_B_ONOFF (5<<12)
> #define TRANS_DDI_EDP_INPUT_C_ONOFF (6<<12)
> #define TRANS_DDI_DP_VC_PAYLOAD_ALLOC (1<<8)
> +#define TRANS_DDI_HDMI_SCRAMBLER_CTS_ENABLE (1<<7)
> +#define TRANS_DDI_HDMI_SCRAMBLER_RESET_FREQ (1<<6)
> #define TRANS_DDI_BFI_ENABLE (1<<4)
> +#define TRANS_DDI_HIGH_TMDS_CHAR_RATE (1<<4)
> +#define TRANS_DDI_HDMI_SCRAMBLING (1<<0)
> +#define TRANS_DDI_HDMI_SCRAMBLING_MASK (TRANS_DDI_HDMI_SCRAMBLER_CTS_ENABLE \
> + | TRANS_DDI_HDMI_SCRAMBLER_RESET_FREQ \
> + | TRANS_DDI_HDMI_SCRAMBLING)
>
> /* DisplayPort Transport Control */
> #define _DP_TP_CTL_A 0x64040
> diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c
> index 0467676..b3e4c4a 100644
> --- a/drivers/gpu/drm/i915/intel_ddi.c
> +++ b/drivers/gpu/drm/i915/intel_ddi.c
> @@ -1309,6 +1309,11 @@ void intel_ddi_enable_transcoder_func(const struct intel_crtc_state *crtc_state)
> temp |= TRANS_DDI_MODE_SELECT_HDMI;
> else
> temp |= TRANS_DDI_MODE_SELECT_DVI;
> +
> + if (crtc_state->hdmi_scrambling)
> + temp |= TRANS_DDI_HDMI_SCRAMBLING_MASK;
> + if (crtc_state->hdmi_high_tmds_clock_ratio)
> + temp |= TRANS_DDI_HIGH_TMDS_CHAR_RATE;
> } else if (type == INTEL_OUTPUT_ANALOG) {
> temp |= TRANS_DDI_MODE_SELECT_FDI;
> temp |= (crtc_state->fdi_lanes - 1) << 1;
> @@ -1882,6 +1887,9 @@ static void intel_enable_ddi(struct intel_encoder *intel_encoder,
> struct intel_digital_port *intel_dig_port =
> enc_to_dig_port(encoder);
>
> + intel_hdmi_handle_sink_scrambling(intel_encoder,
> + conn_state->connector, pipe_config, true);
> +
> /* In HDMI/DVI mode, the port width, and swing/emphasis values
> * are ignored so nothing special needs to be done besides
> * enabling the port.
> @@ -1914,6 +1922,11 @@ static void intel_disable_ddi(struct intel_encoder *intel_encoder,
> if (old_crtc_state->has_audio)
> intel_audio_codec_disable(intel_encoder);
>
> + if (type == INTEL_OUTPUT_HDMI) {
> + intel_hdmi_handle_sink_scrambling(intel_encoder,
> + old_conn_state->connector, old_crtc_state, false);
> + }
> +
> if (type == INTEL_OUTPUT_EDP) {
> struct intel_dp *intel_dp = enc_to_intel_dp(encoder);
>
> @@ -2040,6 +2053,12 @@ void intel_ddi_get_config(struct intel_encoder *encoder,
>
> if (intel_hdmi->infoframe_enabled(&encoder->base, pipe_config))
> pipe_config->has_infoframe = true;
> +
> + if ((temp & TRANS_DDI_HDMI_SCRAMBLING_MASK) ==
> + TRANS_DDI_HDMI_SCRAMBLING_MASK)
> + pipe_config->hdmi_scrambling = true;
> + if (temp & TRANS_DDI_HIGH_TMDS_CHAR_RATE)
> + pipe_config->hdmi_high_tmds_clock_ratio = true;
> /* fall through */
> case TRANS_DDI_MODE_SELECT_DVI:
> pipe_config->lane_count = 4;
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index e77ca7d..fb5e670 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -11701,6 +11701,9 @@ static void __printf(3, 4)
> if ((INTEL_GEN(dev_priv) < 8 && !IS_HASWELL(dev_priv)) ||
> IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv))
> PIPE_CONF_CHECK_I(limited_color_range);
> +
> + 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(has_audio);
> diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
> index 3af20c1..50d680c 100644
> --- a/drivers/gpu/drm/i915/intel_drv.h
> +++ b/drivers/gpu/drm/i915/intel_drv.h
> @@ -729,6 +729,12 @@ struct intel_crtc_state {
>
> /* bitmask of visible planes (enum plane_id) */
> u8 active_planes;
> +
> + /* HDMI scrambling status */
> + bool hdmi_scrambling;
> +
> + /* HDMI High TMDS char rate ratio */
> + bool hdmi_high_tmds_clock_ratio;
> };
>
> struct intel_crtc {
> @@ -1623,6 +1629,10 @@ void intel_hdmi_init_connector(struct intel_digital_port *intel_dig_port,
> bool intel_hdmi_compute_config(struct intel_encoder *encoder,
> struct intel_crtc_state *pipe_config,
> struct drm_connector_state *conn_state);
> +void intel_hdmi_handle_sink_scrambling(struct intel_encoder *intel_encoder,
> + struct drm_connector *connector,
> + struct intel_crtc_state *config,
> + bool enable);
> void intel_dp_dual_mode_set_tmds_output(struct intel_hdmi *hdmi, bool enable);
>
>
> diff --git a/drivers/gpu/drm/i915/intel_hdmi.c b/drivers/gpu/drm/i915/intel_hdmi.c
> index c2184f7..4585aa8 100644
> --- a/drivers/gpu/drm/i915/intel_hdmi.c
> +++ b/drivers/gpu/drm/i915/intel_hdmi.c
> @@ -34,6 +34,7 @@
> #include <drm/drm_atomic_helper.h>
> #include <drm/drm_crtc.h>
> #include <drm/drm_edid.h>
> +#include <drm/drm_scdc_helper.h>
> #include "intel_drv.h"
> #include <drm/i915_drm.h>
> #include <drm/intel_lpe_audio.h>
> @@ -1316,6 +1317,7 @@ 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;
> int clock_8bpc = pipe_config->base.adjusted_mode.crtc_clock;
> int clock_12bpc = clock_8bpc * 3 / 2;
> int desired_bpp;
> @@ -1385,6 +1387,16 @@ bool intel_hdmi_compute_config(struct intel_encoder *encoder,
>
> pipe_config->lane_count = 4;
>
> + if (scdc->scrambling.supported && IS_GEMINILAKE(dev_priv)) {
> + if (scdc->scrambling.low_rates)
> + pipe_config->hdmi_scrambling = true;
> +
> + if (pipe_config->port_clock > 340000) {
> + pipe_config->hdmi_scrambling = true;
> + pipe_config->hdmi_high_tmds_clock_ratio = true;
> + }
> + }
> +
> return true;
> }
>
> @@ -1794,6 +1806,56 @@ static void intel_hdmi_destroy(struct drm_connector *connector)
> intel_hdmi->aspect_ratio = HDMI_PICTURE_ASPECT_NONE;
> }
>
> +/*
> + * This function handles scrambling on HDMI 2.0 capable sinks.
> + * If required clock rate is > 340 Mhz && scrambling is supported by sink
> + * it enables scrambling. This should be called before enabling the HDMI
> + * 2.0 port, as the sink can choose to disable the scrambling if it doesn't
> + * detect a scrambled clock within 100 ms.
> + */
> +void intel_hdmi_handle_sink_scrambling(struct intel_encoder *intel_encoder,
> + struct drm_connector *connector,
> + struct intel_crtc_state *config,
> + bool enable)
> +{
> + struct intel_hdmi *intel_hdmi = enc_to_intel_hdmi(&intel_encoder->base);
> + struct drm_i915_private *dev_priv = connector->dev->dev_private;
> + struct drm_scrambling *scrambling =
> + &connector->display_info.hdmi.scdc.scrambling;
> + struct i2c_adapter *adptr = intel_gmbus_get_adapter(dev_priv,
> + intel_hdmi->ddc_bus);
> + bool ret;
> +
> + if (!scrambling->supported)
> + return;
> +
> + if (!IS_GEMINILAKE(dev_priv))
> + return;
I'd still like to see this getting done uncoditionally. That way we
might get a bit of extra testing for the SCDC helper no matter what
platform the user happens to own.
I presume the spec says the sink will reset these to some default value
on HPD or something like that? But I'm not sure trusting them to get
this right is a good idea because reality often doesn't match the
specs. So the safer option IMO would be always tell the sink exactly
what we want.
> +
> + DRM_DEBUG_KMS("Setting sink scrambling for enc:%s connector:%s\n",
> + intel_encoder->base.name, connector->name);
> +
> + if (config->hdmi_high_tmds_clock_ratio) {
> + /* Set TMDS bit clock ratio to 1/40 or 1/10 */
> + ret = drm_scdc_set_high_tmds_clock_ratio(adptr, enable);
> + if (!ret) {
> + DRM_ERROR("Set TMDS ratio failed\n");
> + return;
> + }
> + }
> +
> + if (config->hdmi_scrambling) {
> + /* Enable/disable sink scrambling */
> + ret = drm_scdc_set_scrambling(adptr, enable);
> + if (!ret) {
> + DRM_ERROR("Set sink scrambling failed\n");
> + return;
> + }
> + }
> +
> + DRM_DEBUG_KMS("sink scrambling handled\n");
> +}
> +
> static u8 intel_hdmi_ddc_pin(struct drm_i915_private *dev_priv,
> enum port port)
> {
> --
> 1.9.1
--
Ville Syrjälä
Intel OTC
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