drm/vc4: hvs: Remove planes currently allocated before taking down

When the HVS driver is unbound, a lot of memory allocations in the LBM and
DLIST RAM are still assigned to planes that are still allocated.

Thus, we hit a warning when calling drm_mm_takedown() since the memory pool
is not completely free of allocations.

Let's free all the currently live entries before calling drm_mm_takedown().
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-17-maxime@cerno.tech

drivers/gpu/drm/vc4/vc4_hvs.c

@@ -873,11 +873,18 @@ static void vc4_hvs_unbind(struct device *dev, struct device *master,
 	struct drm_device *drm = dev_get_drvdata(master);
 	struct vc4_dev *vc4 = to_vc4_dev(drm);
 	struct vc4_hvs *hvs = vc4->hvs;
+	struct drm_mm_node *node, *next;
 
 	if (drm_mm_node_allocated(&vc4->hvs->mitchell_netravali_filter))
 		drm_mm_remove_node(&vc4->hvs->mitchell_netravali_filter);
 
+	drm_mm_for_each_node_safe(node, next, &vc4->hvs->dlist_mm)
+		drm_mm_remove_node(node);
+
 	drm_mm_takedown(&vc4->hvs->dlist_mm);
+
+	drm_mm_for_each_node_safe(node, next, &vc4->hvs->lbm_mm)
+		drm_mm_remove_node(node);
 	drm_mm_takedown(&vc4->hvs->lbm_mm);
 
 	clk_disable_unprepare(hvs->core_clk);