On 11/27/2025 2:46 PM, Mitul Golani wrote:
Track dc balance flip count with params per crtc. Increment DC Balance Flip count before every flip to indicate DMC firmware about new flip occurrence which needs to be adjusted for dc balancing. This is tracked separately from legacy FLIP_COUNT register also Reset DC balance flip count value while disabling VRR adaptive mode, this is to start with fresh counts when VRR adaptive refresh mode is triggered again. --v2: - Call during intel_update_crtc.(Ankit) Signed-off-by: Mitul Golani <[email protected]>
Reviewed-by: Ankit Nautiyal <[email protected]>
--- drivers/gpu/drm/i915/display/intel_display.c | 3 +++ .../gpu/drm/i915/display/intel_display_types.h | 4 ++++ drivers/gpu/drm/i915/display/intel_vrr.c | 15 +++++++++++++++ drivers/gpu/drm/i915/display/intel_vrr.h | 2 ++ 4 files changed, 24 insertions(+) diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c index d41ab965c013..1269f841d48b 100644 --- a/drivers/gpu/drm/i915/display/intel_display.c +++ b/drivers/gpu/drm/i915/display/intel_display.c @@ -6863,6 +6863,9 @@ static void intel_update_crtc(struct intel_atomic_state *state, intel_crtc_update_active_timings(new_crtc_state, new_crtc_state->vrr.enable);+ if (new_crtc_state->vrr.dc_balance.enable)+ intel_vrr_dcb_increment_flip_count(new_crtc_state, crtc); + /* * We usually enable FIFO underrun interrupts as part of the * CRTC enable sequence during modesets. But when we inherit a diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h index 8eb0ace7d918..740c5fc9fe1e 100644 --- a/drivers/gpu/drm/i915/display/intel_display_types.h +++ b/drivers/gpu/drm/i915/display/intel_display_types.h @@ -1501,6 +1501,10 @@ struct intel_crtc { struct intel_link_m_n m_n, m2_n2; } drrs;+ struct {+ u64 flip_count; + } dc_balance; + int scanline_offset;struct {diff --git a/drivers/gpu/drm/i915/display/intel_vrr.c b/drivers/gpu/drm/i915/display/intel_vrr.c index ff65c1167e1b..411ae5da3824 100644 --- a/drivers/gpu/drm/i915/display/intel_vrr.c +++ b/drivers/gpu/drm/i915/display/intel_vrr.c @@ -632,6 +632,20 @@ void intel_vrr_set_transcoder_timings(const struct intel_crtc_state *crtc_state) EMP_AS_SDP_DB_TL(crtc_state->vrr.vsync_start)); }+void+intel_vrr_dcb_increment_flip_count(struct intel_crtc_state *crtc_state, + struct intel_crtc *crtc) +{ + struct intel_display *display = to_intel_display(crtc_state); + enum pipe pipe = crtc->pipe; + + if (!crtc_state->vrr.dc_balance.enable) + return; + + intel_de_write(display, PIPEDMC_DCB_FLIP_COUNT(pipe), + ++crtc->dc_balance.flip_count); +} + void intel_vrr_dcb_reset(const struct intel_crtc_state *old_crtc_state, struct intel_crtc *crtc) @@ -642,6 +656,7 @@ intel_vrr_dcb_reset(const struct intel_crtc_state *old_crtc_state, if (!old_crtc_state->vrr.dc_balance.enable) return;+ intel_de_write(display, PIPEDMC_DCB_FLIP_COUNT(pipe), 0);intel_de_write(display, PIPEDMC_DCB_BALANCE_RESET(pipe), 0); }diff --git a/drivers/gpu/drm/i915/display/intel_vrr.h b/drivers/gpu/drm/i915/display/intel_vrr.hindex d40ed5504180..bedcc8c4bff2 100644 --- a/drivers/gpu/drm/i915/display/intel_vrr.h +++ b/drivers/gpu/drm/i915/display/intel_vrr.h @@ -29,6 +29,8 @@ void intel_vrr_send_push(struct intel_dsb *dsb, const struct intel_crtc_state *crtc_state); void intel_vrr_check_push_sent(struct intel_dsb *dsb, const struct intel_crtc_state *crtc_state); +void intel_vrr_dcb_increment_flip_count(struct intel_crtc_state *crtc_state, + struct intel_crtc *crtc); bool intel_vrr_is_push_sent(const struct intel_crtc_state *crtc_state); void intel_vrr_disable(const struct intel_crtc_state *old_crtc_state); void intel_vrr_get_config(struct intel_crtc_state *crtc_state);
