drm/vc4: crtc: Move HVS init and close to a function

In order to make further refactoring easier, let's move the HVS channel
setup / teardown to their own function.
Signed-off-by: NMaxime Ripard <maxime@cerno.tech>
Tested-by: NChanwoo Choi <cw00.choi@samsung.com>
Tested-by: NHoegeun Kwon <hoegeun.kwon@samsung.com>
Tested-by: NStefan Wahren <stefan.wahren@i2se.com>
Reviewed-by: NDave Stevenson <dave.stevenson@raspberrypi.com>
Link: https://patchwork.freedesktop.org/patch/msgid/fb1b5299d1636ddce8340b51a80d51641839f83b.1599120059.git-series.maxime@cerno.tech

drivers/gpu/drm/vc4/vc4_hvs.c

@@ -196,6 +196,62 @@ static void vc4_hvs_update_gamma_lut(struct drm_crtc *crtc)
 	vc4_hvs_lut_load(crtc);
 }
 
+static int vc4_hvs_init_channel(struct vc4_dev *vc4, struct drm_crtc *crtc,
+				struct drm_display_mode *mode, bool oneshot)
+{
+	struct vc4_crtc_state *vc4_crtc_state = to_vc4_crtc_state(crtc->state);
+	unsigned int chan = vc4_crtc_state->assigned_channel;
+	u32 dispctrl;
+
+	/* Turn on the scaler, which will wait for vstart to start
+	 * compositing.
+	 * When feeding the transposer, we should operate in oneshot
+	 * mode.
+	 */
+	dispctrl = SCALER_DISPCTRLX_ENABLE;
+
+	if (!vc4->hvs->hvs5)
+		dispctrl |= VC4_SET_FIELD(mode->hdisplay,
+					  SCALER_DISPCTRLX_WIDTH) |
+			    VC4_SET_FIELD(mode->vdisplay,
+					  SCALER_DISPCTRLX_HEIGHT) |
+			    (oneshot ? SCALER_DISPCTRLX_ONESHOT : 0);
+	else
+		dispctrl |= VC4_SET_FIELD(mode->hdisplay,
+					  SCALER5_DISPCTRLX_WIDTH) |
+			    VC4_SET_FIELD(mode->vdisplay,
+					  SCALER5_DISPCTRLX_HEIGHT) |
+			    (oneshot ? SCALER5_DISPCTRLX_ONESHOT : 0);
+
+	HVS_WRITE(SCALER_DISPCTRLX(chan), dispctrl);
+
+	return 0;
+}
+
+static void vc4_hvs_stop_channel(struct drm_device *dev, unsigned int chan)
+{
+	struct vc4_dev *vc4 = to_vc4_dev(dev);
+
+	if (HVS_READ(SCALER_DISPCTRLX(chan)) & SCALER_DISPCTRLX_ENABLE)
+		return;
+
+	HVS_WRITE(SCALER_DISPCTRLX(chan),
+		  HVS_READ(SCALER_DISPCTRLX(chan)) | SCALER_DISPCTRLX_RESET);
+	HVS_WRITE(SCALER_DISPCTRLX(chan),
+		  HVS_READ(SCALER_DISPCTRLX(chan)) & ~SCALER_DISPCTRLX_ENABLE);
+
+	/* Once we leave, the scaler should be disabled and its fifo empty. */
+	WARN_ON_ONCE(HVS_READ(SCALER_DISPCTRLX(chan)) & SCALER_DISPCTRLX_RESET);
+
+	WARN_ON_ONCE(VC4_GET_FIELD(HVS_READ(SCALER_DISPSTATX(chan)),
+				   SCALER_DISPSTATX_MODE) !=
+		     SCALER_DISPSTATX_MODE_DISABLED);
+
+	WARN_ON_ONCE((HVS_READ(SCALER_DISPSTATX(chan)) &
+		      (SCALER_DISPSTATX_FULL | SCALER_DISPSTATX_EMPTY)) !=
+		     SCALER_DISPSTATX_EMPTY);
+}
+
 int vc4_hvs_atomic_check(struct drm_crtc *crtc,
 			 struct drm_crtc_state *state)
 {
@@ -268,63 +324,19 @@ void vc4_hvs_atomic_enable(struct drm_crtc *crtc,
 	struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(crtc->state);
 	struct drm_display_mode *mode = &crtc->state->adjusted_mode;
 	bool oneshot = vc4_state->feed_txp;
-	u32 dispctrl;
 
 	vc4_hvs_update_dlist(crtc);
-
-	/* Turn on the scaler, which will wait for vstart to start
-	 * compositing.
-	 * When feeding the transposer, we should operate in oneshot
-	 * mode.
-	 */
-	dispctrl = SCALER_DISPCTRLX_ENABLE;
-
-	if (!vc4->hvs->hvs5)
-		dispctrl |= VC4_SET_FIELD(mode->hdisplay,
-					  SCALER_DISPCTRLX_WIDTH) |
-			    VC4_SET_FIELD(mode->vdisplay,
-					  SCALER_DISPCTRLX_HEIGHT) |
-			    (oneshot ? SCALER_DISPCTRLX_ONESHOT : 0);
-	else
-		dispctrl |= VC4_SET_FIELD(mode->hdisplay,
-					  SCALER5_DISPCTRLX_WIDTH) |
-			    VC4_SET_FIELD(mode->vdisplay,
-					  SCALER5_DISPCTRLX_HEIGHT) |
-			    (oneshot ? SCALER5_DISPCTRLX_ONESHOT : 0);
-
-	HVS_WRITE(SCALER_DISPCTRLX(vc4_state->assigned_channel), dispctrl);
+	vc4_hvs_init_channel(vc4, crtc, mode, oneshot);
 }
 
 void vc4_hvs_atomic_disable(struct drm_crtc *crtc,
 			    struct drm_crtc_state *old_state)
 {
 	struct drm_device *dev = crtc->dev;
-	struct vc4_dev *vc4 = to_vc4_dev(dev);
 	struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(old_state);
 	unsigned int chan = vc4_state->assigned_channel;
 
-	if (HVS_READ(SCALER_DISPCTRLX(chan)) &
-	    SCALER_DISPCTRLX_ENABLE) {
-		HVS_WRITE(SCALER_DISPCTRLX(chan),
-			  SCALER_DISPCTRLX_RESET);
-
-		/* While the docs say that reset is self-clearing, it
-		 * seems it doesn't actually.
-		 */
-		HVS_WRITE(SCALER_DISPCTRLX(chan), 0);
-	}
-
-	/* Once we leave, the scaler should be disabled and its fifo empty. */
-
-	WARN_ON_ONCE(HVS_READ(SCALER_DISPCTRLX(chan)) & SCALER_DISPCTRLX_RESET);
-
-	WARN_ON_ONCE(VC4_GET_FIELD(HVS_READ(SCALER_DISPSTATX(chan)),
-				   SCALER_DISPSTATX_MODE) !=
-		     SCALER_DISPSTATX_MODE_DISABLED);
-
-	WARN_ON_ONCE((HVS_READ(SCALER_DISPSTATX(chan)) &
-		      (SCALER_DISPSTATX_FULL | SCALER_DISPSTATX_EMPTY)) !=
-		     SCALER_DISPSTATX_EMPTY);
+	vc4_hvs_stop_channel(dev, chan);
 }
 
 void vc4_hvs_atomic_flush(struct drm_crtc *crtc,