diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
index 89f0928b042a..c7debaad67f8 100644
--- a/drivers/gpu/drm/drm_irq.c
+++ b/drivers/gpu/drm/drm_irq.c
@@ -777,6 +777,8 @@ bool drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev,
 	 */
 	if (mode->crtc_clock == 0) {
 		DRM_DEBUG("crtc %u: Noop due to uninitialized mode.\n", pipe);
+		WARN_ON_ONCE(drm_drv_uses_atomic_modeset(dev));
+
 		return false;
 	}
 
@@ -1338,6 +1340,10 @@ void drm_crtc_vblank_off(struct drm_crtc *crtc)
 		send_vblank_event(dev, e, seq, &now);
 	}
 	spin_unlock_irqrestore(&dev->event_lock, irqflags);
+
+	/* Will be reset by the modeset helpers when re-enabling the crtc by
+	 * calling drm_calc_timestamping_constants(). */
+	vblank->hwmode.crtc_clock = 0;
 }
 EXPORT_SYMBOL(drm_crtc_vblank_off);
 
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index dccb7c2560fe..04493ef1d2f7 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -720,9 +720,7 @@ static u32 i915_get_vblank_counter(struct drm_device *dev, unsigned int pipe)
 	struct drm_i915_private *dev_priv = to_i915(dev);
 	i915_reg_t high_frame, low_frame;
 	u32 high1, high2, low, pixel, vbl_start, hsync_start, htotal;
-	struct intel_crtc *intel_crtc = intel_get_crtc_for_pipe(dev_priv,
-								pipe);
-	const struct drm_display_mode *mode = &intel_crtc->base.hwmode;
+	const struct drm_display_mode *mode = &dev->vblank[pipe].hwmode;
 	unsigned long irqflags;
 
 	htotal = mode->crtc_htotal;
@@ -779,13 +777,17 @@ static int __intel_get_crtc_scanline(struct intel_crtc *crtc)
 {
 	struct drm_device *dev = crtc->base.dev;
 	struct drm_i915_private *dev_priv = to_i915(dev);
-	const struct drm_display_mode *mode = &crtc->base.hwmode;
+	const struct drm_display_mode *mode;
+	struct drm_vblank_crtc *vblank;
 	enum pipe pipe = crtc->pipe;
 	int position, vtotal;
 
 	if (!crtc->active)
 		return -1;
 
+	vblank = &crtc->base.dev->vblank[drm_crtc_index(&crtc->base)];
+	mode = &vblank->hwmode;
+
 	vtotal = mode->crtc_vtotal;
 	if (mode->flags & DRM_MODE_FLAG_INTERLACE)
 		vtotal /= 2;
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 3617927af269..2f2bb623cf5f 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -11444,12 +11444,6 @@ intel_modeset_update_crtc_state(struct drm_atomic_state *state)
 	for_each_new_crtc_in_state(state, crtc, new_crtc_state, i) {
 		to_intel_crtc(crtc)->config = to_intel_crtc_state(new_crtc_state);
 
-		/* Update hwmode for vblank functions */
-		if (new_crtc_state->active)
-			crtc->hwmode = new_crtc_state->adjusted_mode;
-		else
-			crtc->hwmode.crtc_clock = 0;
-
 		/*
 		 * Update legacy state to satisfy fbc code. This can
 		 * be removed when fbc uses the atomic state.
@@ -15425,8 +15419,6 @@ static void intel_modeset_readout_hw_state(struct drm_device *dev)
 			to_intel_crtc_state(crtc->base.state);
 		int pixclk = 0;
 
-		crtc->base.hwmode = crtc_state->base.adjusted_mode;
-
 		memset(&crtc->base.mode, 0, sizeof(crtc->base.mode));
 		if (crtc_state->base.active) {
 			intel_mode_from_pipe_config(&crtc->base.mode, crtc_state);
@@ -15456,7 +15448,8 @@ static void intel_modeset_readout_hw_state(struct drm_device *dev)
 			if (IS_BROADWELL(dev_priv) && crtc_state->ips_enabled)
 				pixclk = DIV_ROUND_UP(pixclk * 100, 95);
 
-			drm_calc_timestamping_constants(&crtc->base, &crtc->base.hwmode);
+			drm_calc_timestamping_constants(&crtc->base,
+							&crtc_state->base.adjusted_mode);
 			update_scanline_offset(crtc);
 		}