The patch below does not apply to the 5.10-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From eaf5bfe37db871031232d2bf2535b6ca92afbad8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= ville.syrjala@linux.intel.com Date: Thu, 28 Jan 2021 17:59:44 +0200 Subject: [PATCH] drm/i915: Skip vswing programming for TBT MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit
In thunderbolt mode the PHY is owned by the thunderbolt controller. We are not supposed to touch it. So skip the vswing programming as well (we already skipped the other steps not applicable to TBT).
Touching this stuff could supposedly interfere with the PHY programming done by the thunderbolt controller.
Cc: stable@vger.kernel.org Signed-off-by: Ville Syrjälä ville.syrjala@linux.intel.com Link: https://patchwork.freedesktop.org/patch/msgid/20210128155948.13678-1-ville.s... Reviewed-by: Imre Deak imre.deak@intel.com (cherry picked from commit f8c6b615b921d8a1bcd74870f9105e62b0bceff3) Signed-off-by: Jani Nikula jani.nikula@intel.com
diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c b/drivers/gpu/drm/i915/display/intel_ddi.c index bf17365857ca..e1e3ac12f979 100644 --- a/drivers/gpu/drm/i915/display/intel_ddi.c +++ b/drivers/gpu/drm/i915/display/intel_ddi.c @@ -2754,6 +2754,9 @@ static void icl_mg_phy_ddi_vswing_sequence(struct intel_encoder *encoder, int n_entries, ln; u32 val;
+ if (enc_to_dig_port(encoder)->tc_mode == TC_PORT_TBT_ALT) + return; + ddi_translations = icl_get_mg_buf_trans(encoder, crtc_state, &n_entries); if (level >= n_entries) { drm_dbg_kms(&dev_priv->drm, @@ -2890,6 +2893,9 @@ tgl_dkl_phy_ddi_vswing_sequence(struct intel_encoder *encoder, u32 val, dpcnt_mask, dpcnt_val; int n_entries, ln;
+ if (enc_to_dig_port(encoder)->tc_mode == TC_PORT_TBT_ALT) + return; + ddi_translations = tgl_get_dkl_buf_trans(encoder, crtc_state, &n_entries);
if (level >= n_entries)