From 4a68c7516c57a3d03b406c8aaa073c62149aad68 Mon Sep 17 00:00:00 2001 From: Ankit Nautiyal Date: Wed, 17 Jun 2026 10:44:17 +0530 Subject: [PATCH] drm/i915/dsb: Use safe window path when VRR TG is used MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When the VRR timing generator is always used, the hardware behaves as VRR-active regardless of crtc_state->vrr.enable. The DSB paths that depend on the VRR safe window therefore need to follow the VRR code paths in that case too: - dsb_chicken(): program the SAFE_WINDOW chicken bits, - intel_dsb_vblank_evade(): use vmin/vmax vblank starts for the wait window, - intel_dsb_wait_for_delayed_vblank(): wait inside the vmin safe window before the scanline-based delayed vblank wait. Introduce helper pre_commit_use_safe_window() and use it in the three sites v2: Instead of modifying pre_commit_is_vrr_active() use a new helper and use it only in the required places. (Ville). v3: -Keep using pre_commit_is_vrr_active() for DCB path. (Ville) -Add a separate check for fixed RR with VRR TG and use fixed mode vblank start there. (Ville) Signed-off-by: Ankit Nautiyal Reviewed-by: Ville Syrjälä Link: https://patch.msgid.link/20260617051417.2223526-1-ankit.k.nautiyal@intel.com --- drivers/gpu/drm/i915/display/intel_dsb.c | 22 ++++++++++++++++++++-- 1 file changed, 20 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_dsb.c b/drivers/gpu/drm/i915/display/intel_dsb.c index 07dd6318d9cc..d9a270362a82 100644 --- a/drivers/gpu/drm/i915/display/intel_dsb.c +++ b/drivers/gpu/drm/i915/display/intel_dsb.c @@ -210,6 +210,18 @@ static int dsb_scanline_to_hw(struct intel_atomic_state *state, return (scanline + vtotal - intel_crtc_scanline_offset(crtc_state)) % vtotal; } +static +bool pre_commit_use_safe_window(struct intel_atomic_state *state, + struct intel_crtc *crtc) +{ + struct intel_display *display = to_intel_display(crtc->base.dev); + + if (intel_vrr_always_use_vrr_tg(display)) + return true; + + return pre_commit_is_vrr_active(state, crtc); +} + /* * Bspec suggests that we should always set DSB_SKIP_WAITS_EN. We have approach * different from what is explained in Bspec on how flip is considered being @@ -229,7 +241,7 @@ static u32 dsb_chicken(struct intel_atomic_state *state, u32 chicken = intel_psr_use_trans_push(new_crtc_state) ? DSB_SKIP_WAITS_EN : 0; - if (pre_commit_is_vrr_active(state, crtc)) + if (pre_commit_use_safe_window(state, crtc)) chicken |= DSB_CTRL_WAIT_SAFE_WINDOW | DSB_CTRL_NO_WAIT_VBLANK | DSB_INST_WAIT_SAFE_WINDOW | @@ -798,6 +810,12 @@ void intel_dsb_vblank_evade(struct intel_atomic_state *state, end = intel_vrr_vmax_vblank_start(crtc_state); start = end - vblank_delay - latency; intel_dsb_wait_scanline_out(state, dsb, start, end); + } else if (pre_commit_use_safe_window(state, crtc)) { + int vblank_delay = crtc_state->set_context_latency; + + end = intel_mode_vblank_start(&crtc_state->hw.adjusted_mode); + start = end - vblank_delay - latency; + intel_dsb_wait_scanline_out(state, dsb, start, end); } else { int vblank_delay = intel_mode_vblank_delay(&crtc_state->hw.adjusted_mode); @@ -891,7 +909,7 @@ void intel_dsb_wait_for_delayed_vblank(struct intel_atomic_state *state, &crtc_state->hw.adjusted_mode; int wait_scanlines; - if (pre_commit_is_vrr_active(state, crtc)) { + if (pre_commit_use_safe_window(state, crtc)) { /* * If the push happened before the vmin decision boundary * we don't know how far we are from the undelayed vblank.