drm/i915/fbc: Split plane size vs. surface size checks apart

Do separate checks for the visible plane size vs. the surface
size (which I take to mean offset+size). For now both use the
same max w/h, but we can relax the surface size limits as
a followup.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231117171833.25816-1-ville.syrjala@linux.intel.comReviewed-by: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com>

drivers/gpu/drm/i915/display/intel_fbc.c

@@ -1050,6 +1050,31 @@ static bool intel_fbc_hw_tracking_covers_screen(const struct intel_plane_state *
 	return effective_w <= max_w && effective_h <= max_h;
 }
 
+static bool intel_fbc_plane_size_valid(const struct intel_plane_state *plane_state)
+{
+	struct drm_i915_private *i915 = to_i915(plane_state->uapi.plane->dev);
+	unsigned int w, h, max_w, max_h;
+
+	if (DISPLAY_VER(i915) >= 10) {
+		max_w = 5120;
+		max_h = 4096;
+	} else if (DISPLAY_VER(i915) >= 8 || IS_HASWELL(i915)) {
+		max_w = 4096;
+		max_h = 4096;
+	} else if (IS_G4X(i915) || DISPLAY_VER(i915) >= 5) {
+		max_w = 4096;
+		max_h = 2048;
+	} else {
+		max_w = 2048;
+		max_h = 1536;
+	}
+
+	w = drm_rect_width(&plane_state->uapi.src) >> 16;
+	h = drm_rect_height(&plane_state->uapi.src) >> 16;
+
+	return w <= max_w && h <= max_h;
+}
+
 static bool i8xx_fbc_tiling_valid(const struct intel_plane_state *plane_state)
 {
 	const struct drm_framebuffer *fb = plane_state->hw.fb;
@@ -1247,11 +1272,16 @@ static int intel_fbc_check_plane(struct intel_atomic_state *state,
 		return 0;
 	}
 
-	if (!intel_fbc_hw_tracking_covers_screen(plane_state)) {
+	if (!intel_fbc_plane_size_valid(plane_state)) {
 		plane_state->no_fbc_reason = "plane size too big";
 		return 0;
 	}
 
+	if (!intel_fbc_hw_tracking_covers_screen(plane_state)) {
+		plane_state->no_fbc_reason = "surface size too big";
+		return 0;
+	}
+
 	/*
 	 * Work around a problem on GEN9+ HW, where enabling FBC on a plane
 	 * having a Y offset that isn't divisible by 4 causes FIFO underrun