From ea9f962b1ff6eeeca15415cee1a4f1dbb2ce8e41 Mon Sep 17 00:00:00 2001 From: Chaitanya Kumar Borah Date: Thu, 24 Oct 2024 11:40:02 +0530 Subject: [PATCH] drm/i915/dp: Add FEC Enable Retry mechanism Currently, even though there is a bit to control FEC enable/disable individually, the FEC Decode Enable sequence is sent by the SOC only once TRANS_CONF enable is set. This ties the FEC enabling too tightly to modeset and therefore cannot be re-issued (in case of failure) without a modeset. From PTL, FEC_DECODE_EN sequence can be sent to a DPRX independent of TRANS_CONF enable. This allows us to re-issue an FEC_DECODE_EN sequence without a modeset. Hence allowing us to have a retry mechanism in case the DPRX does not respond with an FEC_ENABLE within certain amount of time. While at it, replace struct drm_i915_private with struct intel_display v4: - More code refactor [Jani] - use struct intel_display [Jani] - Optimize logging [Jani] v3: - Make the commit message more legible [Jani] - Refactor code to re-use existing code [Jani] - Do away with platform dependent FEC enable checks [Jani] v2: - Refactor code to avoid duplication and improve readability [Jani] - In case of PTL, wait for FEC status directly after FEC enable [Srikanth] - Wait for FEC_ENABLE_LIVE_STATUS to be cleared before re-enabling FEC [Srikanth] Signed-off-by: Chaitanya Kumar Borah Reviewed-by: Jani Nikula Signed-off-by: Suraj Kandpal Link: https://patchwork.freedesktop.org/patch/msgid/20241024061002.4085137-1-chaitanya.kumar.borah@intel.com --- drivers/gpu/drm/i915/display/intel_ddi.c | 81 +++++++++++++++++------- drivers/gpu/drm/i915/display/intel_ddi.h | 6 +- 2 files changed, 61 insertions(+), 26 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c b/drivers/gpu/drm/i915/display/intel_ddi.c index eca12f0cbeca4..0535daed6a9f1 100644 --- a/drivers/gpu/drm/i915/display/intel_ddi.c +++ b/drivers/gpu/drm/i915/display/intel_ddi.c @@ -2256,9 +2256,9 @@ static int read_fec_detected_status(struct drm_dp_aux *aux) return status; } -static void wait_for_fec_detected(struct drm_dp_aux *aux, bool enabled) +static int wait_for_fec_detected(struct drm_dp_aux *aux, bool enabled) { - struct drm_i915_private *i915 = to_i915(aux->drm_dev); + struct intel_display *display = to_intel_display(aux->drm_dev); int mask = enabled ? DP_FEC_DECODE_EN_DETECTED : DP_FEC_DECODE_DIS_DETECTED; int status; int err; @@ -2267,57 +2267,92 @@ static void wait_for_fec_detected(struct drm_dp_aux *aux, bool enabled) status & mask || status < 0, 10000, 200000); - if (!err && status >= 0) - return; + if (err || status < 0) { + drm_dbg_kms(display->drm, + "Failed waiting for FEC %s to get detected: %d (status %d)\n", + str_enabled_disabled(enabled), err, status); + return err ? err : status; + } - if (err == -ETIMEDOUT) - drm_dbg_kms(&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); + return 0; } -void intel_ddi_wait_for_fec_status(struct intel_encoder *encoder, - const struct intel_crtc_state *crtc_state, - bool enabled) +int 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_display *display = to_intel_display(encoder); struct intel_dp *intel_dp = enc_to_intel_dp(encoder); int ret; if (!crtc_state->fec_enable) - return; + return 0; if (enabled) - ret = intel_de_wait_for_set(i915, dp_tp_status_reg(encoder, crtc_state), + ret = intel_de_wait_for_set(display, 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), + ret = intel_de_wait_for_clear(display, dp_tp_status_reg(encoder, crtc_state), DP_TP_STATUS_FEC_ENABLE_LIVE, 1); - if (ret) - drm_err(&i915->drm, + if (ret) { + drm_err(display->drm, "Timeout waiting for FEC live state to get %s\n", str_enabled_disabled(enabled)); - + return ret; + } /* * 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); + if (enabled) { + ret = wait_for_fec_detected(&intel_dp->aux, enabled); + if (ret) + return ret; + } + + return 0; } static void intel_ddi_enable_fec(struct intel_encoder *encoder, const struct intel_crtc_state *crtc_state) { - struct drm_i915_private *dev_priv = to_i915(encoder->base.dev); + struct intel_display *display = to_intel_display(encoder); + int i; + int ret; if (!crtc_state->fec_enable) return; - intel_de_rmw(dev_priv, dp_tp_ctl_reg(encoder, crtc_state), + intel_de_rmw(display, dp_tp_ctl_reg(encoder, crtc_state), 0, DP_TP_CTL_FEC_ENABLE); + + if (DISPLAY_VER(display) < 30) + return; + + ret = intel_ddi_wait_for_fec_status(encoder, crtc_state, true); + if (!ret) + return; + + for (i = 0; i < 3; i++) { + drm_dbg_kms(display->drm, "Retry FEC enabling\n"); + + intel_de_rmw(display, dp_tp_ctl_reg(encoder, crtc_state), + DP_TP_CTL_FEC_ENABLE, 0); + + ret = intel_ddi_wait_for_fec_status(encoder, crtc_state, false); + if (ret) + continue; + + intel_de_rmw(display, dp_tp_ctl_reg(encoder, crtc_state), + 0, DP_TP_CTL_FEC_ENABLE); + + ret = intel_ddi_wait_for_fec_status(encoder, crtc_state, true); + if (!ret) + return; + } + + drm_err(display->drm, "Failed to enable FEC after retries\n"); } static void intel_ddi_disable_fec(struct intel_encoder *encoder, diff --git a/drivers/gpu/drm/i915/display/intel_ddi.h b/drivers/gpu/drm/i915/display/intel_ddi.h index 6d85422bdefef..640851d46b1bc 100644 --- a/drivers/gpu/drm/i915/display/intel_ddi.h +++ b/drivers/gpu/drm/i915/display/intel_ddi.h @@ -63,9 +63,9 @@ 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); +int 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);