summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorImre Deak <imre.deak@intel.com>2014-01-30 16:50:42 +0200
committerDaniel Vetter <daniel.vetter@ffwll.ch>2014-01-30 17:47:34 +0100
commit2cac613be8d4d661edd359cdab3c474286c4f5f0 (patch)
tree14e3318451d87b3dcf7425baa9b088b2dee915ce
parentec14ba47791965d2c08e0a681ff44eacbf3c4553 (diff)
drm/i915: vlv: fix DP PHY lockup due to invalid PP sequencer setup
Atm we setup the HW panel power sequencer logic both for eDP and DP ports. On eDP we then go on and start the power on sequence and commence with link training when it's ready. On DP we don't do the power on sequencing but do the link training immediately. At this point the DP PHY block gets stuck, since - supposedly - it is waiting for the power on sequence to finish. The actual register write that seems to hold off the PHY is PIPEX_PP_ON_DELAYS[Panel Control Port Select]. Writing here a non-0 value eventually sets PIPEX_PP_STATUS[Require Asset Status] to 1 and blocks the PHY until the panel power on is ready. Fix this by not doing any PP sequencing setup for DP ports. Thanks to Ville Syrjälä, Jesse Barnes and Todd Previte for the help in tracking this down. Note that on older gmch platforms (where we have lvds instead of edp) we've hacked around this by writing the magic ABCD unlock key to PP registers, which disables the hw sanity checks. For edp all platforms thus far had the pch split, with the edp port in the north display complex and the PP registers on the pch the hw sanity checks (expressed through the "Require Asset Status" bit) was never functional, hence never a real issue. This regression has been introduce in commit bf13e81b904a37d94d83dd6c3b53a147719a3ead Author: Jani Nikula <jani.nikula@intel.com> Date: Fri Sep 6 07:40:05 2013 +0300 drm/i915: add support for per-pipe power sequencing on vlv Signed-off-by: Imre Deak <imre.deak@intel.com> [danvet: Add note about the bigger story here.] Cc: stable@vger.kernel.org Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
-rw-r--r--drivers/gpu/drm/i915/intel_dp.c10
1 files changed, 6 insertions, 4 deletions
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 5ede4e8e290..c00b6e352c2 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -1869,10 +1869,12 @@ static void vlv_pre_enable_dp(struct intel_encoder *encoder)
mutex_unlock(&dev_priv->dpio_lock);
- /* init power sequencer on this pipe and port */
- intel_dp_init_panel_power_sequencer(dev, intel_dp, &power_seq);
- intel_dp_init_panel_power_sequencer_registers(dev, intel_dp,
- &power_seq);
+ if (is_edp(intel_dp)) {
+ /* init power sequencer on this pipe and port */
+ intel_dp_init_panel_power_sequencer(dev, intel_dp, &power_seq);
+ intel_dp_init_panel_power_sequencer_registers(dev, intel_dp,
+ &power_seq);
+ }
intel_enable_dp(encoder);