From 4ef619a7dff8940fe622ef1d3cac8e1946a75e92 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Ville=20Syrj=C3=A4l=C3=A4?= Date: Fri, 22 Jan 2021 15:26:44 -0800 Subject: [PATCH] drm/i915/display: Helpers for VRR vblank min and max start MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit With VRR the earliest the registers can get latched are at flipline decision boundary, calculate that as vrr_vmin_vblank_start() and the latest the regsiters can get latched are vmax decision boundary calculate that as vrr_vmax_vblank_start() v2: * Remove TODO and adjust extra scanline const (Manasi) Signed-off-by: Manasi Navare Signed-off-by: Ville Syrjälä Reviewed-by: Manasi Navare Link: https://patchwork.freedesktop.org/patch/msgid/20210122232647.22688-15-manasi.d.navare@intel.com --- drivers/gpu/drm/i915/display/intel_vrr.c | 36 ++++++++++++++++++++++++ drivers/gpu/drm/i915/display/intel_vrr.h | 2 ++ 2 files changed, 38 insertions(+) diff --git a/drivers/gpu/drm/i915/display/intel_vrr.c b/drivers/gpu/drm/i915/display/intel_vrr.c index c71254563a102..49ff5add90e05 100644 --- a/drivers/gpu/drm/i915/display/intel_vrr.c +++ b/drivers/gpu/drm/i915/display/intel_vrr.c @@ -45,6 +45,42 @@ intel_vrr_check_modeset(struct intel_atomic_state *state) } } +/* + * Without VRR registers get latched at: + * vblank_start + * + * With VRR the earliest registers can get latched is: + * intel_vrr_vmin_vblank_start(), which if we want to maintain + * the correct min vtotal is >=vblank_start+1 + * + * The latest point registers can get latched is the vmax decision boundary: + * intel_vrr_vmax_vblank_start() + * + * Between those two points the vblank exit starts (and hence registers get + * latched) ASAP after a push is sent. + * + * framestart_delay is programmable 0-3. + */ +static int intel_vrr_vblank_exit_length(const struct intel_crtc_state *crtc_state) +{ + struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc); + struct drm_i915_private *i915 = to_i915(crtc->base.dev); + + /* The hw imposes the extra scanline before frame start */ + return crtc_state->vrr.pipeline_full + i915->framestart_delay + 1; +} + +int intel_vrr_vmin_vblank_start(const struct intel_crtc_state *crtc_state) +{ + /* Min vblank actually determined by flipline that is always >=vmin+1 */ + return crtc_state->vrr.vmin + 1 - intel_vrr_vblank_exit_length(crtc_state); +} + +int intel_vrr_vmax_vblank_start(const struct intel_crtc_state *crtc_state) +{ + return crtc_state->vrr.vmax - intel_vrr_vblank_exit_length(crtc_state); +} + void intel_vrr_compute_config(struct intel_crtc_state *crtc_state, struct drm_connector_state *conn_state) diff --git a/drivers/gpu/drm/i915/display/intel_vrr.h b/drivers/gpu/drm/i915/display/intel_vrr.h index 8a2fe9ceba46a..fac01bf4ab500 100644 --- a/drivers/gpu/drm/i915/display/intel_vrr.h +++ b/drivers/gpu/drm/i915/display/intel_vrr.h @@ -27,5 +27,7 @@ void intel_vrr_send_push(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 *crtc, struct intel_crtc_state *crtc_state); +int intel_vrr_vmax_vblank_start(const struct intel_crtc_state *crtc_state); +int intel_vrr_vmin_vblank_start(const struct intel_crtc_state *crtc_state); #endif /* __INTEL_VRR_H__ */ -- 2.39.5