[PATCH v21 19/19] drm/i915: Do not do fb src adjustments for NV12

[Vidya Srinivas]

We skip src trunction/adjustments for
NV12 case and handle the sizes directly.
Without this, pipe fifo underruns are seen on APL/KBL.

Credits-to: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
Signed-off-by: Vidya Srinivas <vidya.srinivas at intel.com>
---
 drivers/gpu/drm/i915/intel_atomic_plane.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/drivers/gpu/drm/i915/intel_atomic_plane.c b/drivers/gpu/drm/i915/intel_atomic_plane.c
index 3ce808e..06c93f5 100644
--- a/drivers/gpu/drm/i915/intel_atomic_plane.c
+++ b/drivers/gpu/drm/i915/intel_atomic_plane.c
@@ -160,9 +160,17 @@ intel_atomic_helper_check_plane_state(struct drm_plane_state *plane_state,
 	if (crtc_state->enable)
 		drm_mode_get_hv_timing(&crtc_state->mode, &clip.x2, &clip.y2);
 
+	if (fb->format->format == DRM_FORMAT_NV12) {
+		plane_state->visible =
+			(drm_rect_width(dst) > 0 &&
+			 drm_rect_height(dst) > 0);
+		goto skip_rect_clipping;
+	}
+
 	plane_state->visible =
 		drm_rect_clip_scaled(src, dst, &clip, hscale, vscale);
 
+skip_rect_clipping:
 	crtc_x = dst->x1;
 	crtc_y = dst->y1;
 	crtc_w = drm_rect_width(dst);
@@ -186,6 +194,8 @@ intel_atomic_helper_check_plane_state(struct drm_plane_state *plane_state,
 			return vscale;
 		}
 
+		if (fb->format->format == DRM_FORMAT_NV12)
+			goto skip_rect_adjust;
 		/*
 		 * Make the source viewport size an
 		 * exact multiple of the scaling factors
@@ -196,6 +206,7 @@ intel_atomic_helper_check_plane_state(struct drm_plane_state *plane_state,
 				     (drm_rect_height(dst) * vscale -
 				      drm_rect_height(src)));
 
+skip_rect_adjust:
 		drm_rect_rotate_inv(src, fb->width << 16,
 				    fb->height << 16, rotation);
 
@@ -258,6 +269,9 @@ intel_atomic_helper_check_plane_state(struct drm_plane_state *plane_state,
 		}
 	}
 
+	if (fb->format->format == DRM_FORMAT_NV12)
+		goto out;
+
 	if (plane_state->visible) {
 		src->x1 = src_x << 16;
 		src->x2 = (src_x + src_w) << 16;
@@ -269,6 +283,7 @@ intel_atomic_helper_check_plane_state(struct drm_plane_state *plane_state,
 	dst->y1 = crtc_y;
 	dst->y2 = crtc_y + crtc_h;
 
+out:
 	if (!plane_state->visible)
 		/*
 		 * Plane isn't visible; some drivers can handle this
-- 
2.7.4