drm/i915: Add skl_check_nv12_surface for NV12

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

v2: For NV12, making the src coordinates multiplier of 4

v3: Moving all the src coords handling code for NV12
to skl_check_nv12_surface

v4: Added RB from Mika

v5: Rebased the series. Removed checks of mult of 4 in
skl_update_scaler, Added NV12 condition in intel_check_sprite_plane
where src x/w is being checked for mult of 2 for yuv planes.

v6: Made changes to skl_check_nv12_surface as per WA#1106
Reviewed-by: Mika Kahola <mika.kahola@intel.com>
Signed-off-by: Vidya Srinivas <vidya.srinivas@intel.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1526074397-10457-4-git-send-email-vidya.srinivas@intel.com

drivers/gpu/drm/i915/intel_display.c

@@ -3102,6 +3102,29 @@ static int skl_check_main_surface(const struct intel_crtc_state *crtc_state,
 	return 0;
 }
 
+static int
+skl_check_nv12_surface(const struct intel_crtc_state *crtc_state,
+		       struct intel_plane_state *plane_state)
+{
+	/* Display WA #1106 */
+	if (plane_state->base.rotation !=
+	    (DRM_MODE_REFLECT_X | DRM_MODE_ROTATE_90) &&
+	    plane_state->base.rotation != DRM_MODE_ROTATE_270)
+		return 0;
+
+	/*
+	 * src coordinates are rotated here.
+	 * We check height but report it as width
+	 */
+	if (((drm_rect_height(&plane_state->base.src) >> 16) % 4) != 0) {
+		DRM_DEBUG_KMS("src width must be multiple "
+			      "of 4 for rotated NV12\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
 static int skl_check_nv12_aux_surface(struct intel_plane_state *plane_state)
 {
 	const struct drm_framebuffer *fb = plane_state->base.fb;
@@ -3185,6 +3208,9 @@ int skl_check_plane_surface(const struct intel_crtc_state *crtc_state,
 	 * the main surface setup depends on it.
 	 */
 	if (fb->format->format == DRM_FORMAT_NV12) {
+		ret = skl_check_nv12_surface(crtc_state, plane_state);
+		if (ret)
+			return ret;
 		ret = skl_check_nv12_aux_surface(plane_state);
 		if (ret)
 			return ret;
@@ -4806,8 +4832,7 @@ skl_update_scaler(struct intel_crtc_state *crtc_state, bool force_detach,
 	}
 
 	if (plane_scaler_check && pixel_format == DRM_FORMAT_NV12 &&
-	    (src_h < SKL_MIN_YUV_420_SRC_H || (src_w % 4) != 0 ||
-	     (src_h % 4) != 0)) {
+	    (src_h < SKL_MIN_YUV_420_SRC_H || src_w < SKL_MIN_YUV_420_SRC_W)) {
 		DRM_DEBUG_KMS("NV12: src dimensions not met\n");
 		return -EINVAL;
 	}

drivers/gpu/drm/i915/intel_sprite.c

@@ -1060,7 +1060,8 @@ intel_check_sprite_plane(struct intel_plane *plane,
 		src_y = src->y1 >> 16;
 		src_h = drm_rect_height(src) >> 16;
 
-		if (intel_format_is_yuv(fb->format->format)) {
+		if (intel_format_is_yuv(fb->format->format) &&
+		    fb->format->format != DRM_FORMAT_NV12) {
 			src_x &= ~1;
 			src_w &= ~1;