[PATCH 1/7] drm/tilcdc: Enable sync lost error and recovery handling for rev 1 LCDC

[Jyri Sarha]

Revision 1 LCDC support also sync lost errors and can benefit from
sync lost recovery routine.

Signed-off-by: Jyri Sarha <jsarha at ti.com>
---
 drivers/gpu/drm/tilcdc/tilcdc_crtc.c | 39 ++++++++++++++++++------------------
 drivers/gpu/drm/tilcdc/tilcdc_regs.h |  1 +
 2 files changed, 21 insertions(+), 19 deletions(-)

diff --git a/drivers/gpu/drm/tilcdc/tilcdc_crtc.c b/drivers/gpu/drm/tilcdc/tilcdc_crtc.c
index c787349..dfe5796 100644
--- a/drivers/gpu/drm/tilcdc/tilcdc_crtc.c
+++ b/drivers/gpu/drm/tilcdc/tilcdc_crtc.c
@@ -113,8 +113,8 @@ static void tilcdc_crtc_enable_irqs(struct drm_device *dev)
 
 	if (priv->rev == 1) {
 		tilcdc_set(dev, LCDC_RASTER_CTRL_REG,
-			LCDC_V1_UNDERFLOW_INT_ENA);
-		tilcdc_set(dev, LCDC_DMA_CTRL_REG,
+			LCDC_V1_UNDERFLOW_INT_ENA |
+			LCDC_V1_SYNC_LOST_ENA |
 			LCDC_V1_END_OF_FRAME_INT_ENA);
 	} else {
 		tilcdc_write(dev, LCDC_INT_ENABLE_SET_REG,
@@ -131,8 +131,9 @@ static void tilcdc_crtc_disable_irqs(struct drm_device *dev)
 	/* disable irqs that we might have enabled: */
 	if (priv->rev == 1) {
 		tilcdc_clear(dev, LCDC_RASTER_CTRL_REG,
-			LCDC_V1_UNDERFLOW_INT_ENA | LCDC_V1_PL_INT_ENA);
-		tilcdc_clear(dev, LCDC_DMA_CTRL_REG,
+			LCDC_V1_UNDERFLOW_INT_ENA |
+			LCDC_V1_PL_INT_ENA |
+			LCDC_V1_SYNC_LOST_ENA |
 			LCDC_V1_END_OF_FRAME_INT_ENA);
 	} else {
 		tilcdc_write(dev, LCDC_INT_ENABLE_CLR_REG,
@@ -845,6 +846,21 @@ irqreturn_t tilcdc_crtc_irq(struct drm_crtc *crtc)
 		dev_err_ratelimited(dev->dev, "%s(0x%08x): FIFO underflow",
 				    __func__, stat);
 
+	if (stat & LCDC_SYNC_LOST) {
+		dev_err_ratelimited(dev->dev, "%s(0x%08x): Sync lost",
+				    __func__, stat);
+		tilcdc_crtc->frame_intact = false;
+		if (tilcdc_crtc->sync_lost_count++ >
+		    SYNC_LOST_COUNT_LIMIT) {
+			dev_err(dev->dev, "%s(0x%08x): Sync lost flood detected, recovering", __func__, stat);
+			queue_work(system_wq,
+				   &tilcdc_crtc->recover_work);
+			tilcdc_write(dev, LCDC_INT_ENABLE_CLR_REG,
+				     LCDC_SYNC_LOST);
+			tilcdc_crtc->sync_lost_count = 0;
+		}
+	}
+
 	/* For revision 2 only */
 	if (priv->rev == 2) {
 		if (stat & LCDC_FRAME_DONE) {
@@ -852,21 +868,6 @@ irqreturn_t tilcdc_crtc_irq(struct drm_crtc *crtc)
 			wake_up(&tilcdc_crtc->frame_done_wq);
 		}
 
-		if (stat & LCDC_SYNC_LOST) {
-			dev_err_ratelimited(dev->dev, "%s(0x%08x): Sync lost",
-					    __func__, stat);
-			tilcdc_crtc->frame_intact = false;
-			if (tilcdc_crtc->sync_lost_count++ >
-			    SYNC_LOST_COUNT_LIMIT) {
-				dev_err(dev->dev, "%s(0x%08x): Sync lost flood detected, recovering", __func__, stat);
-				queue_work(system_wq,
-					   &tilcdc_crtc->recover_work);
-				tilcdc_write(dev, LCDC_INT_ENABLE_CLR_REG,
-					     LCDC_SYNC_LOST);
-				tilcdc_crtc->sync_lost_count = 0;
-			}
-		}
-
 		/* Indicate to LCDC that the interrupt service routine has
 		 * completed, see 13.3.6.1.6 in AM335x TRM.
 		 */
diff --git a/drivers/gpu/drm/tilcdc/tilcdc_regs.h b/drivers/gpu/drm/tilcdc/tilcdc_regs.h
index f57c0d6..beb8c21 100644
--- a/drivers/gpu/drm/tilcdc/tilcdc_regs.h
+++ b/drivers/gpu/drm/tilcdc/tilcdc_regs.h
@@ -61,6 +61,7 @@
 #define LCDC_V2_UNDERFLOW_INT_ENA                BIT(5)
 #define LCDC_V1_PL_INT_ENA                       BIT(4)
 #define LCDC_V2_PL_INT_ENA                       BIT(6)
+#define LCDC_V1_SYNC_LOST_ENA                    BIT(5)
 #define LCDC_MONOCHROME_MODE                     BIT(1)
 #define LCDC_RASTER_ENABLE                       BIT(0)
 #define LCDC_TFT_ALT_ENABLE                      BIT(23)
-- 
1.9.1