Hi Ville, > -----Original Message----- > From: Intel-gfx <[email protected]> On Behalf Of Ville > Syrjala > Sent: 04 April 2023 23:24 > To: [email protected] > Subject: [Intel-gfx] [PATCH 1/3] drm/i915: Allow arbitrary refresh rates with > VRR eDP panels > > From: Ville Syrjälä <[email protected]> > > If the panel supports VRR it must be capable of accepting timings with > arbitrary vblank length, within the valid VRR range. Use that fact to allow > the > user to request any refresh rate they like. We simply pick the next highest > fixed mode from our list, and adjust the vblank to get the desired refresh > rate in the end. > > Of course currently everything to do with the vrefresh is using 1Hz precision, > so might not be exact. But we can improve that in the future by just upping > our vrefresh precision. > > Signed-off-by: Ville Syrjälä <[email protected]> > --- > drivers/gpu/drm/i915/display/intel_panel.c | 80 ++++++++++++++++++---- > 1 file changed, 66 insertions(+), 14 deletions(-) > > diff --git a/drivers/gpu/drm/i915/display/intel_panel.c > b/drivers/gpu/drm/i915/display/intel_panel.c > index ce2a34a25211..9acdd68b2dbc 100644 > --- a/drivers/gpu/drm/i915/display/intel_panel.c > +++ b/drivers/gpu/drm/i915/display/intel_panel.c > @@ -42,6 +42,7 @@ > #include "intel_lvds_regs.h" > #include "intel_panel.h" > #include "intel_quirks.h" > +#include "intel_vrr.h" > > bool intel_panel_use_ssc(struct drm_i915_private *i915) { @@ -58,6 +59,38 > @@ intel_panel_preferred_fixed_mode(struct intel_connector *connector) > struct drm_display_mode, head); > } > > +static bool is_in_vrr_range(struct intel_connector *connector, int > +vrefresh) { > + const struct drm_display_info *info = &connector- > >base.display_info; > + > + return intel_vrr_is_capable(connector) && > + vrefresh >= info->monitor_range.min_vfreq && > + vrefresh <= info->monitor_range.max_vfreq; } > + > +static bool is_best_fixed_mode(struct intel_connector *connector, > + int vrefresh, int fixed_mode_vrefresh, > + const struct drm_display_mode *best_mode) { > + /* we want to always return something */ > + if (!best_mode) > + return true; > + > + /* > + * With VRR always pick a mode with equal/higher than requested > + * vrefresh, which we can then reduce to match the requested > + * vrefresh by extending the vblank length. > + */ > + if (is_in_vrr_range(connector, vrefresh) && > + is_in_vrr_range(connector, fixed_mode_vrefresh) && > + fixed_mode_vrefresh < vrefresh) > + return false; > + > + /* pick the fixed_mode that is closest in terms of vrefresh */ > + return abs(fixed_mode_vrefresh - vrefresh) < > + abs(drm_mode_vrefresh(best_mode) - vrefresh); } > + > const struct drm_display_mode * > intel_panel_fixed_mode(struct intel_connector *connector, > const struct drm_display_mode *mode) @@ -65,11 > +98,11 @@ intel_panel_fixed_mode(struct intel_connector *connector, > const struct drm_display_mode *fixed_mode, *best_mode = NULL; > int vrefresh = drm_mode_vrefresh(mode); > > - /* pick the fixed_mode that is closest in terms of vrefresh */ > list_for_each_entry(fixed_mode, &connector->panel.fixed_modes, > head) { > - if (!best_mode || > - abs(drm_mode_vrefresh(fixed_mode) - vrefresh) < > - abs(drm_mode_vrefresh(best_mode) - vrefresh)) > + int fixed_mode_vrefresh = > drm_mode_vrefresh(fixed_mode); > + > + if (is_best_fixed_mode(connector, vrefresh, > + fixed_mode_vrefresh, best_mode)) > best_mode = fixed_mode; > } > > @@ -178,27 +211,46 @@ int intel_panel_compute_config(struct > intel_connector *connector, { > const struct drm_display_mode *fixed_mode = > intel_panel_fixed_mode(connector, adjusted_mode); > + int vrefresh, fixed_mode_vrefresh; > + bool is_vrr; > > if (!fixed_mode) > return 0; > > + vrefresh = drm_mode_vrefresh(adjusted_mode); > + fixed_mode_vrefresh = drm_mode_vrefresh(fixed_mode); > + > /* > - * We don't want to lie too much to the user about the refresh > - * rate they're going to get. But we have to allow a bit of latitude > - * for Xorg since it likes to automagically cook up modes with slightly > - * off refresh rates. > + * Assume that we shouldn't muck about with the > + * timings if they don't land in the VRR range. > */ > - if (abs(drm_mode_vrefresh(adjusted_mode) - > drm_mode_vrefresh(fixed_mode)) > 1) { > - drm_dbg_kms(connector->base.dev, > - "[CONNECTOR:%d:%s] Requested mode vrefresh > (%d Hz) does not match fixed mode vrefresh (%d Hz)\n", > - connector->base.base.id, connector->base.name, > - drm_mode_vrefresh(adjusted_mode), > drm_mode_vrefresh(fixed_mode)); > + is_vrr = is_in_vrr_range(connector, vrefresh) && > + is_in_vrr_range(connector, fixed_mode_vrefresh); > > - return -EINVAL; > + if (!is_vrr) { > + /* > + * We don't want to lie too much to the user about the > refresh > + * rate they're going to get. But we have to allow a bit of > latitude > + * for Xorg since it likes to automagically cook up modes with > slightly > + * off refresh rates. > + */ > + if (abs(vrefresh - fixed_mode_vrefresh) > 1) { > + drm_dbg_kms(connector->base.dev, > + "[CONNECTOR:%d:%s] Requested mode > vrefresh (%d Hz) does not match fixed mode vrefresh (%d Hz)\n", > + connector->base.base.id, connector- > >base.name, > + vrefresh, fixed_mode_vrefresh); > + > + return -EINVAL; > + } > } > > drm_mode_copy(adjusted_mode, fixed_mode); > > + if (is_vrr && fixed_mode_vrefresh != vrefresh) > + adjusted_mode->vtotal = > + DIV_ROUND_CLOSEST(adjusted_mode->clock * 1000, > + adjusted_mode->htotal * vrefresh); > +
Changes LGTM Thanks Reviewed-by: Mitul Golani <[email protected]> > drm_mode_set_crtcinfo(adjusted_mode, 0); > > return 0; > -- > 2.39.2
