On Thu, Mar 19, 2020 at 03:20:50PM -0700, Manasi Navare wrote: > On Thu, Mar 19, 2020 at 06:38:42PM +0200, Ville Syrjala wrote: > > From: Ville Syrjälä <[email protected]> > > > > Some new eDP panels don't like to operate at the max parameters, and > > instead we need to go for an optimal confiugration. That unfortunately > > doesn't work with older eDP panels which are generally only guaranteed > > to work at the max parameters. > > > > To solve these two conflicting requirements let's start with the optimal > > setup, and if that fails we start again with the max parameters. The > > downside is probably an extra modeset when we switch strategies but > > I don't see a good way to avoid that. > > > > For a bit of history we first tried to go for the fast+narrow in > > commit 7769db588384 ("drm/i915/dp: optimize eDP 1.4+ link config > > fast and narrow"). but that had to be reverted due to regression > > on older panels in commit f11cb1c19ad0 ("drm/i915/dp: revert back > > to max link rate and lane count on eDP"). So now we try to get > > the best of both worlds by using both strategies. > > > > v2: Deal with output_bpp and uapi vs. hw state split > > Reword some comments > > > > Cc: Jani Nikula <[email protected]> > > Cc: Rodrigo Vivi <[email protected]> > > Cc: Manasi Navare <[email protected]> > > Cc: Albert Astals Cid <[email protected]> # v5.0 backport > > Cc: Emanuele Panigati <[email protected]> # v5.0 backport > > Cc: Matteo Iervasi <[email protected]> # v5.0 backport > > Cc: Timo Aaltonen <[email protected]> > > References: https://bugs.freedesktop.org/show_bug.cgi?id=105267 > > References: https://bugs.freedesktop.org/show_bug.cgi?id=109959 > > References: https://gitlab.freedesktop.org/drm/intel/issues/272 > > Signed-off-by: Ville Syrjälä <[email protected]> > > This approach looks good to me to fallback to max parameters if > it fails the first time. > > > --- > > .../drm/i915/display/intel_display_types.h | 1 + > > drivers/gpu/drm/i915/display/intel_dp.c | 74 ++++++++++++++++--- > > 2 files changed, 66 insertions(+), 9 deletions(-) > > > > diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h > > b/drivers/gpu/drm/i915/display/intel_display_types.h > > index 5e00e611f077..ffde0d4af23c 100644 > > --- a/drivers/gpu/drm/i915/display/intel_display_types.h > > +++ b/drivers/gpu/drm/i915/display/intel_display_types.h > > @@ -1258,6 +1258,7 @@ struct intel_dp { > > bool link_trained; > > bool has_audio; > > bool reset_link_params; > > + bool use_max_params; > > u8 dpcd[DP_RECEIVER_CAP_SIZE]; > > u8 psr_dpcd[EDP_PSR_RECEIVER_CAP_SIZE]; > > u8 downstream_ports[DP_MAX_DOWNSTREAM_PORTS]; > > diff --git a/drivers/gpu/drm/i915/display/intel_dp.c > > b/drivers/gpu/drm/i915/display/intel_dp.c > > index ef2e06e292d5..85abcce492ca 100644 > > --- a/drivers/gpu/drm/i915/display/intel_dp.c > > +++ b/drivers/gpu/drm/i915/display/intel_dp.c > > @@ -465,6 +465,12 @@ int intel_dp_get_link_train_fallback_values(struct > > intel_dp *intel_dp, > > { > > int index; > > > > + if (intel_dp_is_edp(intel_dp) && !intel_dp->use_max_params) { > > + DRM_DEBUG_KMS("Retrying Link training for eDP with max > > parameters\n"); > > + intel_dp->use_max_params = true; > > + return 0; > > + } > > We need to remove the current check for > intel_dp_can_link_train_fallback_for_edp() right?
No. Why do you think it needs to be removed? -- Ville Syrjälä Intel _______________________________________________ Intel-gfx mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/intel-gfx
