From: Jyri Sarha <jsarha@ti.com>
Date: Fri, 26 May 2017 13:20:17 +0300
Subject: drm/tilcdc: Turn raster off in crtc reset, if it was on in the HW
Git-commit: 46a956ab3c5be9141b75c0a6d8a754bdd4426577
Patch-mainline: v4.15-rc1
References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166

This forces the HW to be in sync with the empty state. This should
help with the problem when LCDC is already enabled (e.g. by the
bootloader) at the initialization phase and the enable fails when a
new mode is applied.

Signed-off-by: Jyri Sarha <jsarha@ti.com>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
 drivers/gpu/drm/tilcdc/tilcdc_crtc.c |   30 +++++++++++++++++++++++++++++-
 1 file changed, 29 insertions(+), 1 deletion(-)

--- a/drivers/gpu/drm/tilcdc/tilcdc_crtc.c
+++ b/drivers/gpu/drm/tilcdc/tilcdc_crtc.c
@@ -728,11 +728,39 @@ static void tilcdc_crtc_disable_vblank(s
 {
 }
 
+static void tilcdc_crtc_reset(struct drm_crtc *crtc)
+{
+	struct tilcdc_crtc *tilcdc_crtc = to_tilcdc_crtc(crtc);
+	struct drm_device *dev = crtc->dev;
+	int ret;
+
+	drm_atomic_helper_crtc_reset(crtc);
+
+	/* Turn the raster off if it for some reason is on. */
+	pm_runtime_get_sync(dev->dev);
+	if (tilcdc_read(dev, LCDC_RASTER_CTRL_REG) & LCDC_RASTER_ENABLE) {
+		/* Enable DMA Frame Done Interrupt */
+		tilcdc_write(dev, LCDC_INT_ENABLE_SET_REG, LCDC_FRAME_DONE);
+		tilcdc_clear_irqstatus(dev, 0xffffffff);
+
+		tilcdc_crtc->frame_done = false;
+		tilcdc_clear(dev, LCDC_RASTER_CTRL_REG, LCDC_RASTER_ENABLE);
+
+		ret = wait_event_timeout(tilcdc_crtc->frame_done_wq,
+					 tilcdc_crtc->frame_done,
+					 msecs_to_jiffies(500));
+		if (ret == 0)
+			dev_err(dev->dev, "%s: timeout waiting for framedone\n",
+				__func__);
+	}
+	pm_runtime_put_sync(dev->dev);
+}
+
 static const struct drm_crtc_funcs tilcdc_crtc_funcs = {
 	.destroy        = tilcdc_crtc_destroy,
 	.set_config     = drm_atomic_helper_set_config,
 	.page_flip      = drm_atomic_helper_page_flip,
-	.reset		= drm_atomic_helper_crtc_reset,
+	.reset		= tilcdc_crtc_reset,
 	.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
 	.atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
 	.enable_vblank	= tilcdc_crtc_enable_vblank,