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]> --- 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
