[PATCH v8 5/6] drm/i915: enable scrambling
Sharma, Shashank
shashank.sharma at intel.com
Wed Mar 8 17:50:45 UTC 2017
Regards
Shashank
On 3/8/2017 7:44 PM, Ville Syrjälä wrote:
> On Wed, Mar 08, 2017 at 07:26:45PM +0200, Sharma, Shashank wrote:
>> Regards
>>
>> Shashank
>>
>>
>> On 3/8/2017 7:17 PM, Ville Syrjälä wrote:
>>> 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.
>> Sure, seems a good idea. I just added this hear to address the review
>> comment from Ander.
>> Also, I can move this IS_GLK condition to compute_config, and once we
>> check this in compute_config
>> we might never have check it again.
> I thought you already had the check in there? Hmm. Looks that way to me.
Yep, I already have that (this shows I have too many versions of code in
my mind too :P),
what I meant was, we can use some of those state checks here before
enabling/disabling sink side scrambling.
But then I realized it won't be the unconditional stuff you actually
want, so please rub my last comment off :-)
- Shashank
>>> 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.
>> Yep, You are correct about the spec too, that it says if there is no
>> scrambled clock post hpd_out for
>> 100ms, the sink should disable scrambling. But connected modeset
>> scenarios need our attention, where
>> for example we are switching mode from, 4k at 60 (scrambling reqd) ->
>> 1080 at 60 (scrambling not reqd).
>> For such cases too, we have to tell sink to disable scrambling.
>>>> +
>>>> + 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
More information about the dri-devel
mailing list