On Thu, Mar 27, 2025 at 10:00:19AM +0200, Jani Nikula wrote: > On Wed, 26 Mar 2025, Ville Syrjala <[email protected]> wrote: > > From: Ville Syrjälä <[email protected]> > > > > Currently intel_bw_calc_min_cdclk() always adds the bw_state > > to the atomic state. Not only does it result in potentially > > redundant work later, it's also currently causing unwanted cdclk > > changes during driver load. > > Can you elaborate how we currently end up changing cdclk even if the > dbuf bw isn't changing? Different rules wrt to GOP?
Older GOP versions always use the max cdclk. IIRC newer ones might be using a more optimal value. > > Anyway, the change make sense no matter what, > > Reviewed-by: Jani Nikula <[email protected]> > > > > > > Check if the dbuf bw is actually changing before we decide to > > pull in the bw state. > > > > Signed-off-by: Ville Syrjälä <[email protected]> > > --- > > drivers/gpu/drm/i915/display/intel_bw.c | 17 +++++++++++++---- > > 1 file changed, 13 insertions(+), 4 deletions(-) > > > > diff --git a/drivers/gpu/drm/i915/display/intel_bw.c > > b/drivers/gpu/drm/i915/display/intel_bw.c > > index 67d088da1f38..19b516084fac 100644 > > --- a/drivers/gpu/drm/i915/display/intel_bw.c > > +++ b/drivers/gpu/drm/i915/display/intel_bw.c > > @@ -1294,7 +1294,8 @@ int intel_bw_calc_min_cdclk(struct intel_atomic_state > > *state, > > struct intel_bw_state *new_bw_state = NULL; > > const struct intel_bw_state *old_bw_state = NULL; > > const struct intel_cdclk_state *cdclk_state; > > - const struct intel_crtc_state *crtc_state; > > + const struct intel_crtc_state *old_crtc_state; > > + const struct intel_crtc_state *new_crtc_state; > > int old_min_cdclk, new_min_cdclk; > > struct intel_crtc *crtc; > > int i; > > @@ -1302,15 +1303,23 @@ int intel_bw_calc_min_cdclk(struct > > intel_atomic_state *state, > > if (DISPLAY_VER(display) < 9) > > return 0; > > > > - for_each_new_intel_crtc_in_state(state, crtc, crtc_state, i) { > > + for_each_oldnew_intel_crtc_in_state(state, crtc, old_crtc_state, > > + new_crtc_state, i) { > > + struct intel_dbuf_bw old_dbuf_bw, new_dbuf_bw; > > + > > + skl_crtc_calc_dbuf_bw(&old_dbuf_bw, old_crtc_state); > > + skl_crtc_calc_dbuf_bw(&new_dbuf_bw, new_crtc_state); > > + > > + if (!intel_dbuf_bw_changed(display, &old_dbuf_bw, &new_dbuf_bw)) > > + continue; > > + > > new_bw_state = intel_atomic_get_bw_state(state); > > if (IS_ERR(new_bw_state)) > > return PTR_ERR(new_bw_state); > > > > old_bw_state = intel_atomic_get_old_bw_state(state); > > > > - skl_crtc_calc_dbuf_bw(&new_bw_state->dbuf_bw[crtc->pipe], > > - crtc_state); > > + new_bw_state->dbuf_bw[crtc->pipe] = new_dbuf_bw; > > } > > > > if (!old_bw_state) > > -- > Jani Nikula, Intel -- Ville Syrjälä Intel
