diff mbox series

[v2,30/31] drm/vc4: hvs: Enable SCALER_CONTROL early in HVS init

Message ID 20240621152055.4180873-31-dave.stevenson@raspberrypi.com (mailing list archive)
State New, archived
Headers show
Series Preparatory patches for BCM2712 (Pi5) support | expand

Commit Message

Dave Stevenson June 21, 2024, 3:20 p.m. UTC 
From: Tim Gover <tim.gover@raspberrypi.com>

Always enable SCALER_CONTROL before attempting other HVS
operations. It's safe to write to some parts of the HVS but
in general it's dangerous to do this because it can cause bus
lockups.

Signed-off-by: Tim Gover <tim.gover@raspberrypi.com>
Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
---
 drivers/gpu/drm/vc4/vc4_hvs.c | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)
diff mbox series

Patch

diff --git a/drivers/gpu/drm/vc4/vc4_hvs.c b/drivers/gpu/drm/vc4/vc4_hvs.c
index fc147aff53c3..be2173f6c58e 100644
--- a/drivers/gpu/drm/vc4/vc4_hvs.c
+++ b/drivers/gpu/drm/vc4/vc4_hvs.c
@@ -860,6 +860,10 @@  static int vc4_hvs_hw_init(struct vc4_hvs *hvs)
 	struct vc4_dev *vc4 = hvs->vc4;
 	u32 dispctrl, reg;
 
+	dispctrl = HVS_READ(SCALER_DISPCTRL);
+	dispctrl |= SCALER_DISPCTRL_ENABLE;
+	HVS_WRITE(SCALER_DISPCTRL, dispctrl);
+
 	reg = HVS_READ(SCALER_DISPECTRL);
 	reg &= ~SCALER_DISPECTRL_DSP2_MUX_MASK;
 	HVS_WRITE(SCALER_DISPECTRL,
@@ -881,8 +885,6 @@  static int vc4_hvs_hw_init(struct vc4_hvs *hvs)
 		  reg | VC4_SET_FIELD(3, SCALER_DISPDITHER_DSP5_MUX));
 
 	dispctrl = HVS_READ(SCALER_DISPCTRL);
-
-	dispctrl |= SCALER_DISPCTRL_ENABLE;
 	dispctrl |= SCALER_DISPCTRL_DISPEIRQ(0) |
 		    SCALER_DISPCTRL_DISPEIRQ(1) |
 		    SCALER_DISPCTRL_DISPEIRQ(2);
@@ -1078,6 +1080,10 @@  static int vc4_hvs_bind(struct device *dev, struct device *master, void *data)
 	else
 		hvs->dlist = hvs->regs + SCALER5_DLIST_START;
 
+	ret = vc4_hvs_hw_init(hvs);
+	if (ret)
+		return ret;
+
 	/* Upload filter kernels.  We only have the one for now, so we
 	 * keep it around for the lifetime of the driver.
 	 */
@@ -1087,10 +1093,6 @@  static int vc4_hvs_bind(struct device *dev, struct device *master, void *data)
 	if (ret)
 		return ret;
 
-	ret = vc4_hvs_hw_init(hvs);
-	if (ret)
-		return ret;
-
 	ret = vc4_hvs_cob_init(hvs);
 	if (ret)
 		return ret;