As we move towards using a shorter, optimized guardband, we need to adjust how the delayed vblank start is computed.
Introduce intel_crtc_compute_vrr_guardband() to handle guardband computation and apply vblank_start adjustment for platforms that always use the VRR timing generator. This function wraps the existing intel_vrr_compute_guardband() and adjusts crtc_vblank_start using (vblank_length - guardband) only when intel_vrr_always_use_vrr_tg() is true. Since the guardband is not yet optimized, the adjustment currently evaluates to zero, preserving existing behavior. This paves way for guardband optimization, by handling the movement of the crtc_vblank_start for platforms that have VRR TG always active. Also update allow_vblank_delay_fastset() to permit vblank delay adjustments during fastboot when VRR TG is always active, even without inherited state. Signed-off-by: Ankit Nautiyal <[email protected]> --- drivers/gpu/drm/i915/display/intel_display.c | 33 ++++++++++++++++++-- 1 file changed, 30 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c index b2d4e24fd7c6..1964e41b5704 100644 --- a/drivers/gpu/drm/i915/display/intel_display.c +++ b/drivers/gpu/drm/i915/display/intel_display.c @@ -2403,6 +2403,27 @@ static int intel_crtc_compute_set_context_latency(struct intel_atomic_state *sta return 0; } +static void intel_crtc_compute_vrr_guardband(struct intel_atomic_state *state, + struct intel_crtc *crtc) +{ + struct intel_display *display = to_intel_display(state); + struct intel_crtc_state *crtc_state = + intel_atomic_get_new_crtc_state(state, crtc); + struct drm_display_mode *adjusted_mode = + &crtc_state->hw.adjusted_mode; + + intel_vrr_compute_guardband(crtc_state); + + if (intel_vrr_always_use_vrr_tg(display)) { + int vblank_length = adjusted_mode->crtc_vtotal - + (crtc_state->set_context_latency + + adjusted_mode->crtc_vdisplay); + + adjusted_mode->crtc_vblank_start += + vblank_length - crtc_state->vrr.guardband; + } +} + static int intel_crtc_compute_config(struct intel_atomic_state *state, struct intel_crtc *crtc) { @@ -2414,7 +2435,7 @@ static int intel_crtc_compute_config(struct intel_atomic_state *state, if (ret) return ret; - intel_vrr_compute_guardband(crtc_state); + intel_crtc_compute_vrr_guardband(state, crtc); ret = intel_dpll_crtc_compute_clock(state, crtc); if (ret) @@ -5105,9 +5126,15 @@ static bool allow_vblank_delay_fastset(const struct intel_crtc_state *old_crtc_s * Allow fastboot to fix up vblank delay (handled via LRR * codepaths), a bit dodgy as the registers aren't * double buffered but seems to be working more or less... + * + * Also allow this when the VRR timing generator is always on, + * which implies optimized guardband is used. In such cases, + * vblank delay may vary even without inherited state, but it's + * still safe as VRR guardband is still same. */ - return HAS_LRR(display) && old_crtc_state->inherited && - !intel_crtc_has_type(old_crtc_state, INTEL_OUTPUT_DSI); + return HAS_LRR(display) && + (old_crtc_state->inherited || intel_vrr_always_use_vrr_tg(display)) && + !intel_crtc_has_type(old_crtc_state, INTEL_OUTPUT_DSI); } bool -- 2.45.2
