diff mbox series

[1/2,SRU,G] drm/i915/tgl+: Use the correct DP_TP_* register instances in MST encoders

Message ID 20200910052736.314874-2-shane.lin@canonical.com
State New
Headers show
Series Support WD19TB external output on TGL platform | expand

Commit Message

Hsuan-Yu Lin Sept. 10, 2020, 5:27 a.m. UTC
From: Imre Deak <imre.deak@intel.com>

BugLink: https://bugs.launchpad.net/bugs/1886165

MST encoders must use the master MST transcoder's DP_TP_STATUS and
DP_TP_CONTROL registers. Atm, during the HW readout of an MST encoder
connected to a slave transcoder we reset these register addresses in
intel_dp::regs.dp_tp_* to the slave transcoder's DP_TP_* register
addresses incorrectly; fix this.

One example where the above overwite happens is the encoder HW state
validation after enabling multiple streams; see
intel_dp_mst_enc_get_config(). After that during disabling any stream
we'll get a

'Timed out waiting for ACT sent when disabling'

error, due to reading from the incorrect DP_TP_STATUS register.

This change replaces
https://patchwork.freedesktop.org/patch/369577/?series=78193&rev=1
which just papered over the problem.

v2:
- Correct the failure scenario in the commit log. (José)

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: José Roberto de Souza <jose.souza@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200616211146.23027-1-imre.deak@intel.com
(cherry picked from commit f153478de4b259afb0a383de83e817b4c237401b)
Signed-off-by: Hsuan-Yu Lin <shane.lin@canonical.com>
---
 drivers/gpu/drm/i915/display/intel_ddi.c | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)
diff mbox series

Patch

diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c b/drivers/gpu/drm/i915/display/intel_ddi.c
index 0575a1eea2a1..898491a17b78 100644
--- a/drivers/gpu/drm/i915/display/intel_ddi.c
+++ b/drivers/gpu/drm/i915/display/intel_ddi.c
@@ -4155,11 +4155,6 @@  void intel_ddi_get_config(struct intel_encoder *encoder,
 	if (drm_WARN_ON(&dev_priv->drm, transcoder_is_dsi(cpu_transcoder)))
 		return;
 
-	if (INTEL_GEN(dev_priv) >= 12) {
-		intel_dp->regs.dp_tp_ctl = TGL_DP_TP_CTL(cpu_transcoder);
-		intel_dp->regs.dp_tp_status = TGL_DP_TP_STATUS(cpu_transcoder);
-	}
-
 	intel_dsc_get_config(encoder, pipe_config);
 
 	temp = intel_de_read(dev_priv, TRANS_DDI_FUNC_CTL(cpu_transcoder));
@@ -4261,6 +4256,16 @@  void intel_ddi_get_config(struct intel_encoder *encoder,
 		break;
 	}
 
+	if (INTEL_GEN(dev_priv) >= 12) {
+		enum transcoder transcoder =
+			intel_dp_mst_is_slave_trans(pipe_config) ?
+			pipe_config->mst_master_transcoder :
+			pipe_config->cpu_transcoder;
+
+		intel_dp->regs.dp_tp_ctl = TGL_DP_TP_CTL(transcoder);
+		intel_dp->regs.dp_tp_status = TGL_DP_TP_STATUS(transcoder);
+	}
+
 	pipe_config->has_audio =
 		intel_ddi_is_audio_enabled(dev_priv, cpu_transcoder);