From 90780a633cec2c904adbd9027f003d7eea89254b Mon Sep 17 00:00:00 2001 From: Imre Deak Date: Wed, 11 Oct 2023 20:16:04 +0300 Subject: drm/i915/dp: Sanitize DPCD revision check in intel_dp_get_dsc_sink_cap() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Check only the eDP or the DP specific DPCD revision depending on the sink type. Pass the corresponding revision to the function, which allows getting the DSC caps of a branch device (in an MST topology, which has its own DPCD and so DPCD revision). While at it use DP_DPCD_REV_14 instead of open coding it and for clarity add a separate function to read out the DSC capability on eDP. v2: - Use DP_DPCD_REV_14 instead of open coding it. (Stan) - Check EDP_DCPD_REV/DPCD_REV in a clearer way. (Ville) v3: - Fix the read-out for eDP in intel_dp_detect(). Cc: Ville Syrjälä Reviewed-by: Stanislav Lisovskiy (v1) Reviewed-by: Ville Syrjälä (v2) Signed-off-by: Imre Deak Link: https://patchwork.freedesktop.org/patch/msgid/20231011171606.2540078-1-imre.deak@intel.com --- drivers/gpu/drm/i915/display/intel_dp.c | 81 ++++++++++++++++++++++----------- 1 file changed, 55 insertions(+), 26 deletions(-) (limited to 'drivers') diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c index f0f43aeabd21..a010e021c48c 100644 --- a/drivers/gpu/drm/i915/display/intel_dp.c +++ b/drivers/gpu/drm/i915/display/intel_dp.c @@ -3467,7 +3467,23 @@ bool intel_dp_get_colorimetry_status(struct intel_dp *intel_dp) return dprx & DP_VSC_SDP_EXT_FOR_COLORIMETRY_SUPPORTED; } -static void intel_dp_get_dsc_sink_cap(struct intel_dp *intel_dp) +static void intel_dp_read_dsc_dpcd(struct drm_dp_aux *aux, + u8 dsc_dpcd[DP_DSC_RECEIVER_CAP_SIZE]) +{ + if (drm_dp_dpcd_read(aux, DP_DSC_SUPPORT, dsc_dpcd, + DP_DSC_RECEIVER_CAP_SIZE) < 0) { + drm_err(aux->drm_dev, + "Failed to read DPCD register 0x%x\n", + DP_DSC_SUPPORT); + return; + } + + drm_dbg_kms(aux->drm_dev, "DSC DPCD: %*ph\n", + DP_DSC_RECEIVER_CAP_SIZE, + dsc_dpcd); +} + +static void intel_dp_get_dsc_sink_cap(u8 dpcd_rev, struct intel_dp *intel_dp) { struct drm_i915_private *i915 = dp_to_i915(intel_dp); @@ -3480,30 +3496,27 @@ static void intel_dp_get_dsc_sink_cap(struct intel_dp *intel_dp) /* Clear fec_capable to avoid using stale values */ intel_dp->fec_capable = 0; - /* Cache the DSC DPCD if eDP or DP rev >= 1.4 */ - if (intel_dp->dpcd[DP_DPCD_REV] >= 0x14 || - intel_dp->edp_dpcd[0] >= DP_EDP_14) { - if (drm_dp_dpcd_read(&intel_dp->aux, DP_DSC_SUPPORT, - intel_dp->dsc_dpcd, - sizeof(intel_dp->dsc_dpcd)) < 0) - drm_err(&i915->drm, - "Failed to read DPCD register 0x%x\n", - DP_DSC_SUPPORT); - - drm_dbg_kms(&i915->drm, "DSC DPCD: %*ph\n", - (int)sizeof(intel_dp->dsc_dpcd), - intel_dp->dsc_dpcd); + if (dpcd_rev < DP_DPCD_REV_14) + return; - /* FEC is supported only on DP 1.4 */ - if (!intel_dp_is_edp(intel_dp) && - drm_dp_dpcd_readb(&intel_dp->aux, DP_FEC_CAPABILITY, - &intel_dp->fec_capable) < 0) - drm_err(&i915->drm, - "Failed to read FEC DPCD register\n"); + intel_dp_read_dsc_dpcd(&intel_dp->aux, intel_dp->dsc_dpcd); - drm_dbg_kms(&i915->drm, "FEC CAPABILITY: %x\n", - intel_dp->fec_capable); + if (drm_dp_dpcd_readb(&intel_dp->aux, DP_FEC_CAPABILITY, + &intel_dp->fec_capable) < 0) { + drm_err(&i915->drm, "Failed to read FEC DPCD register\n"); + return; } + + drm_dbg_kms(&i915->drm, "FEC CAPABILITY: %x\n", + intel_dp->fec_capable); +} + +static void intel_edp_get_dsc_sink_cap(u8 edp_dpcd_rev, struct intel_dp *intel_dp) +{ + if (edp_dpcd_rev < DP_EDP_14) + return; + + intel_dp_read_dsc_dpcd(&intel_dp->aux, intel_dp->dsc_dpcd); } static void intel_edp_mso_mode_fixup(struct intel_connector *connector, @@ -3674,7 +3687,8 @@ intel_edp_init_dpcd(struct intel_dp *intel_dp) /* Read the eDP DSC DPCD registers */ if (HAS_DSC(dev_priv)) - intel_dp_get_dsc_sink_cap(intel_dp); + intel_edp_get_dsc_sink_cap(intel_dp->edp_dpcd[0], + intel_dp); /* * If needed, program our source OUI so we can make various Intel-specific AUX services @@ -5342,6 +5356,23 @@ intel_dp_unset_edid(struct intel_dp *intel_dp) false); } +static void +intel_dp_detect_dsc_caps(struct intel_dp *intel_dp) +{ + struct drm_i915_private *i915 = dp_to_i915(intel_dp); + + /* Read DP Sink DSC Cap DPCD regs for DP v1.4 */ + if (!HAS_DSC(i915)) + return; + + if (intel_dp_is_edp(intel_dp)) + intel_edp_get_dsc_sink_cap(intel_dp->edp_dpcd[0], + intel_dp); + else + intel_dp_get_dsc_sink_cap(intel_dp->dpcd[DP_DPCD_REV], + intel_dp); +} + static int intel_dp_detect(struct drm_connector *connector, struct drm_modeset_acquire_ctx *ctx, @@ -5386,9 +5417,7 @@ intel_dp_detect(struct drm_connector *connector, goto out; } - /* Read DP Sink DSC Cap DPCD regs for DP v1.4 */ - if (HAS_DSC(dev_priv)) - intel_dp_get_dsc_sink_cap(intel_dp); + intel_dp_detect_dsc_caps(intel_dp); intel_dp_configure_mst(intel_dp); -- cgit v1.2.3