diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index 1f7cc404f3b77..abcc2a36aa957 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -4015,7 +4015,7 @@ static int intel_dp_sink_crc_stop(struct intel_dp *intel_dp) goto out; } - intel_dp->sink_crc_started = false; + intel_dp->sink_crc.started = false; out: hsw_enable_ips(intel_crtc); return ret; @@ -4028,7 +4028,7 @@ static int intel_dp_sink_crc_start(struct intel_dp *intel_dp) u8 buf; int ret; - if (intel_dp->sink_crc_started) { + if (intel_dp->sink_crc.started) { ret = intel_dp_sink_crc_stop(intel_dp); if (ret) return ret; @@ -4040,6 +4040,8 @@ static int intel_dp_sink_crc_start(struct intel_dp *intel_dp) if (!(buf & DP_TEST_CRC_SUPPORTED)) return -ENOTTY; + intel_dp->sink_crc.last_count = buf & DP_TEST_COUNT_MASK; + if (drm_dp_dpcd_readb(&intel_dp->aux, DP_TEST_SINK, &buf) < 0) return -EIO; @@ -4051,7 +4053,7 @@ static int intel_dp_sink_crc_start(struct intel_dp *intel_dp) return -EIO; } - intel_dp->sink_crc_started = true; + intel_dp->sink_crc.started = true; return 0; } @@ -4061,29 +4063,39 @@ int intel_dp_sink_crc(struct intel_dp *intel_dp, u8 *crc) struct drm_device *dev = dig_port->base.base.dev; struct intel_crtc *intel_crtc = to_intel_crtc(dig_port->base.base.crtc); u8 buf; - int test_crc_count; + int count, ret; int attempts = 6; - int ret; ret = intel_dp_sink_crc_start(intel_dp); if (ret) return ret; - if (drm_dp_dpcd_readb(&intel_dp->aux, DP_TEST_SINK_MISC, &buf) < 0) { - ret = -EIO; - goto stop; - } - - test_crc_count = buf & DP_TEST_COUNT_MASK; - do { + intel_wait_for_vblank(dev, intel_crtc->pipe); + if (drm_dp_dpcd_readb(&intel_dp->aux, DP_TEST_SINK_MISC, &buf) < 0) { ret = -EIO; goto stop; } - intel_wait_for_vblank(dev, intel_crtc->pipe); - } while (--attempts && (buf & DP_TEST_COUNT_MASK) == test_crc_count); + count = buf & DP_TEST_COUNT_MASK; + /* + * Count might be reset during the loop. In this case + * last known count needs to be reset as well. + */ + if (count == 0) + intel_dp->sink_crc.last_count = 0; + + if (drm_dp_dpcd_read(&intel_dp->aux, DP_TEST_CRC_R_CR, crc, 6) < 0) { + ret = -EIO; + goto stop; + } + } while (--attempts && (count == 0 || (count == intel_dp->sink_crc.last_count && + !memcmp(intel_dp->sink_crc.last_crc, crc, + 6 * sizeof(u8))))); + + intel_dp->sink_crc.last_count = buf & DP_TEST_COUNT_MASK; + memcpy(intel_dp->sink_crc.last_crc, crc, 6 * sizeof(u8)); if (attempts == 0) { DRM_DEBUG_KMS("Panel is unable to calculate CRC after 6 vblanks\n"); @@ -4091,8 +4103,6 @@ int intel_dp_sink_crc(struct intel_dp *intel_dp, u8 *crc) goto stop; } - if (drm_dp_dpcd_read(&intel_dp->aux, DP_TEST_CRC_R_CR, crc, 6) < 0) - ret = -EIO; stop: intel_dp_sink_crc_stop(intel_dp); return ret; diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h index 8858bb18d18eb..6b3e2c6e6c541 100644 --- a/drivers/gpu/drm/i915/intel_drv.h +++ b/drivers/gpu/drm/i915/intel_drv.h @@ -696,6 +696,12 @@ enum link_m_n_set { M2_N2 }; +struct sink_crc { + bool started; + u8 last_crc[6]; + int last_count; +}; + struct intel_dp { uint32_t output_reg; uint32_t aux_ch_ctl_reg; @@ -713,7 +719,7 @@ struct intel_dp { /* sink rates as reported by DP_SUPPORTED_LINK_RATES */ uint8_t num_sink_rates; int sink_rates[DP_MAX_SUPPORTED_RATES]; - bool sink_crc_started; + struct sink_crc sink_crc; struct drm_dp_aux aux; uint8_t train_set[4]; int panel_power_up_delay;