On Tue, Oct 24, 2023 at 04:09:14AM +0300, Imre Deak wrote: > As required by the DP standard wait for the sink to detect the FEC > decode enabling symbol sent by the source. > > Signed-off-by: Imre Deak <[email protected]>
Reviewed-by: Stanislav Lisovskiy <[email protected]> > --- > drivers/gpu/drm/i915/display/intel_ddi.c | 73 +++++++++++++++++++++ > drivers/gpu/drm/i915/display/intel_ddi.h | 3 + > drivers/gpu/drm/i915/display/intel_dp_mst.c | 4 ++ > 3 files changed, 80 insertions(+) > > diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c > b/drivers/gpu/drm/i915/display/intel_ddi.c > index dac3b59758af7..6f9d0f2ff3d9a 100644 > --- a/drivers/gpu/drm/i915/display/intel_ddi.c > +++ b/drivers/gpu/drm/i915/display/intel_ddi.c > @@ -25,6 +25,7 @@ > * > */ > > +#include <linux/iopoll.h> > #include <linux/string_helpers.h> > > #include <drm/display/drm_scdc_helper.h> > @@ -2220,6 +2221,74 @@ static void intel_dp_sink_set_fec_ready(struct > intel_dp *intel_dp, > if (drm_dp_dpcd_writeb(&intel_dp->aux, DP_FEC_CONFIGURATION, > DP_FEC_READY) <= 0) > drm_dbg_kms(&i915->drm, > "Failed to set FEC_READY in the sink\n"); > + > + if (drm_dp_dpcd_writeb(&intel_dp->aux, DP_FEC_STATUS, > + DP_FEC_DECODE_EN_DETECTED | > DP_FEC_DECODE_DIS_DETECTED) <= 0) > + drm_dbg_kms(&i915->drm, "Failed to clear FEC detected flags\n"); > +} > + > +static int read_fec_detected_status(struct drm_dp_aux *aux) > +{ > + int ret; > + u8 status; > + > + ret = drm_dp_dpcd_readb(aux, DP_FEC_STATUS, &status); > + if (ret < 0) > + return ret; > + > + return status; > +} > + > +static void wait_for_fec_detected(struct drm_dp_aux *aux, bool enabled) > +{ > + struct drm_i915_private *i915 = to_i915(aux->drm_dev); > + int mask = enabled ? DP_FEC_DECODE_EN_DETECTED : > DP_FEC_DECODE_DIS_DETECTED; > + int status; > + int err; > + > + err = readx_poll_timeout(read_fec_detected_status, aux, status, > + status & mask || status < 0, > + 10000, 200000); > + > + if (!err && status >= 0) > + return; > + > + if (err == -ETIMEDOUT) > + drm_err(&i915->drm, "Timeout waiting for FEC %s to get > detected\n", > + str_enabled_disabled(enabled)); > + else > + drm_dbg_kms(&i915->drm, "FEC detected status read error: %d\n", > status); > +} > + > +void intel_ddi_wait_for_fec_status(struct intel_encoder *encoder, > + const struct intel_crtc_state *crtc_state, > + bool enabled) > +{ > + struct drm_i915_private *i915 = to_i915(crtc_state->uapi.crtc->dev); > + struct intel_dp *intel_dp = enc_to_intel_dp(encoder); > + int ret; > + > + if (!crtc_state->fec_enable) > + return; > + > + if (enabled) > + ret = intel_de_wait_for_set(i915, dp_tp_status_reg(encoder, > crtc_state), > + DP_TP_STATUS_FEC_ENABLE_LIVE, 1); > + else > + ret = intel_de_wait_for_clear(i915, dp_tp_status_reg(encoder, > crtc_state), > + DP_TP_STATUS_FEC_ENABLE_LIVE, 1); > + > + if (ret) > + drm_err(&i915->drm, > + "Timeout waiting for FEC live state to get %s\n", > + str_enabled_disabled(enabled)); > + > + /* > + * At least the Synoptics MST hub doesn't set the detected flag for > + * FEC decoding disabling so skip waiting for that. > + */ > + if (enabled) > + wait_for_fec_detected(&intel_dp->aux, enabled); > } > > static void intel_ddi_enable_fec(struct intel_encoder *encoder, > @@ -2887,6 +2956,8 @@ static void intel_disable_ddi_buf(struct intel_encoder > *encoder, > } else { > disable_ddi_buf(encoder, crtc_state); > } > + > + intel_ddi_wait_for_fec_status(encoder, crtc_state, false); > } > > static void intel_ddi_post_disable_dp(struct intel_atomic_state *state, > @@ -3248,6 +3319,8 @@ static void intel_enable_ddi(struct intel_atomic_state > *state, > if (!intel_crtc_is_bigjoiner_slave(crtc_state)) > intel_ddi_enable_transcoder_func(encoder, crtc_state); > > + intel_ddi_wait_for_fec_status(encoder, crtc_state, true); > + > /* Enable/Disable DP2.0 SDP split config before transcoder */ > intel_audio_sdp_split_update(crtc_state); > > diff --git a/drivers/gpu/drm/i915/display/intel_ddi.h > b/drivers/gpu/drm/i915/display/intel_ddi.h > index 4999c0ee229bd..e939b93fc81c2 100644 > --- a/drivers/gpu/drm/i915/display/intel_ddi.h > +++ b/drivers/gpu/drm/i915/display/intel_ddi.h > @@ -60,6 +60,9 @@ void intel_ddi_disable_transcoder_func(const struct > intel_crtc_state *crtc_state > void intel_ddi_enable_transcoder_clock(struct intel_encoder *encoder, > const struct intel_crtc_state > *crtc_state); > void intel_ddi_disable_transcoder_clock(const struct intel_crtc_state > *crtc_state); > +void intel_ddi_wait_for_fec_status(struct intel_encoder *encoder, > + const struct intel_crtc_state *crtc_state, > + bool enabled); > void intel_ddi_set_dp_msa(const struct intel_crtc_state *crtc_state, > const struct drm_connector_state *conn_state); > bool intel_ddi_connector_get_hw_state(struct intel_connector > *intel_connector); > diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c > b/drivers/gpu/drm/i915/display/intel_dp_mst.c > index b7a9ce40cf59a..a1ea75cd5ea84 100644 > --- a/drivers/gpu/drm/i915/display/intel_dp_mst.c > +++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c > @@ -853,6 +853,7 @@ static void intel_mst_enable_dp(struct intel_atomic_state > *state, > struct drm_dp_mst_topology_state *mst_state = > drm_atomic_get_new_mst_topology_state(&state->base, > &intel_dp->mst_mgr); > enum transcoder trans = pipe_config->cpu_transcoder; > + bool first_mst_stream = intel_dp->active_mst_links == 1; > > drm_WARN_ON(&dev_priv->drm, pipe_config->has_pch_encoder); > > @@ -879,6 +880,9 @@ static void intel_mst_enable_dp(struct intel_atomic_state > *state, > > wait_for_act_sent(encoder, pipe_config); > > + if (first_mst_stream) > + intel_ddi_wait_for_fec_status(encoder, pipe_config, true); > + > drm_dp_add_payload_part2(&intel_dp->mst_mgr, &state->base, > drm_atomic_get_mst_payload_state(mst_state, > connector->port)); > > -- > 2.39.2 >
