v4.19.13 snapshot.
diff --git a/include/drm/drm_agpsupport.h b/include/drm/drm_agpsupport.h
new file mode 100644
index 0000000..b05e462
--- /dev/null
+++ b/include/drm/drm_agpsupport.h
@@ -0,0 +1,149 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _DRM_AGPSUPPORT_H_
+#define _DRM_AGPSUPPORT_H_
+
+#include <linux/agp_backend.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/mm.h>
+#include <linux/mutex.h>
+#include <linux/types.h>
+#include <uapi/drm/drm.h>
+
+struct drm_device;
+struct drm_file;
+
+struct drm_agp_head {
+	struct agp_kern_info agp_info;
+	struct list_head memory;
+	unsigned long mode;
+	struct agp_bridge_data *bridge;
+	int enabled;
+	int acquired;
+	unsigned long base;
+	int agp_mtrr;
+	int cant_use_aperture;
+	unsigned long page_mask;
+};
+
+#if IS_ENABLED(CONFIG_AGP)
+
+void drm_free_agp(struct agp_memory * handle, int pages);
+int drm_bind_agp(struct agp_memory * handle, unsigned int start);
+int drm_unbind_agp(struct agp_memory * handle);
+struct agp_memory *drm_agp_bind_pages(struct drm_device *dev,
+				struct page **pages,
+				unsigned long num_pages,
+				uint32_t gtt_offset,
+				uint32_t type);
+
+struct drm_agp_head *drm_agp_init(struct drm_device *dev);
+void drm_legacy_agp_clear(struct drm_device *dev);
+int drm_agp_acquire(struct drm_device *dev);
+int drm_agp_acquire_ioctl(struct drm_device *dev, void *data,
+			  struct drm_file *file_priv);
+int drm_agp_release(struct drm_device *dev);
+int drm_agp_release_ioctl(struct drm_device *dev, void *data,
+			  struct drm_file *file_priv);
+int drm_agp_enable(struct drm_device *dev, struct drm_agp_mode mode);
+int drm_agp_enable_ioctl(struct drm_device *dev, void *data,
+			 struct drm_file *file_priv);
+int drm_agp_info(struct drm_device *dev, struct drm_agp_info *info);
+int drm_agp_info_ioctl(struct drm_device *dev, void *data,
+		       struct drm_file *file_priv);
+int drm_agp_alloc(struct drm_device *dev, struct drm_agp_buffer *request);
+int drm_agp_alloc_ioctl(struct drm_device *dev, void *data,
+			struct drm_file *file_priv);
+int drm_agp_free(struct drm_device *dev, struct drm_agp_buffer *request);
+int drm_agp_free_ioctl(struct drm_device *dev, void *data,
+		       struct drm_file *file_priv);
+int drm_agp_unbind(struct drm_device *dev, struct drm_agp_binding *request);
+int drm_agp_unbind_ioctl(struct drm_device *dev, void *data,
+			 struct drm_file *file_priv);
+int drm_agp_bind(struct drm_device *dev, struct drm_agp_binding *request);
+int drm_agp_bind_ioctl(struct drm_device *dev, void *data,
+		       struct drm_file *file_priv);
+
+#else /* CONFIG_AGP */
+
+static inline void drm_free_agp(struct agp_memory * handle, int pages)
+{
+}
+
+static inline int drm_bind_agp(struct agp_memory * handle, unsigned int start)
+{
+	return -ENODEV;
+}
+
+static inline int drm_unbind_agp(struct agp_memory * handle)
+{
+	return -ENODEV;
+}
+
+static inline struct agp_memory *drm_agp_bind_pages(struct drm_device *dev,
+					      struct page **pages,
+					      unsigned long num_pages,
+					      uint32_t gtt_offset,
+					      uint32_t type)
+{
+	return NULL;
+}
+
+static inline struct drm_agp_head *drm_agp_init(struct drm_device *dev)
+{
+	return NULL;
+}
+
+static inline void drm_legacy_agp_clear(struct drm_device *dev)
+{
+}
+
+static inline int drm_agp_acquire(struct drm_device *dev)
+{
+	return -ENODEV;
+}
+
+static inline int drm_agp_release(struct drm_device *dev)
+{
+	return -ENODEV;
+}
+
+static inline int drm_agp_enable(struct drm_device *dev,
+				 struct drm_agp_mode mode)
+{
+	return -ENODEV;
+}
+
+static inline int drm_agp_info(struct drm_device *dev,
+			       struct drm_agp_info *info)
+{
+	return -ENODEV;
+}
+
+static inline int drm_agp_alloc(struct drm_device *dev,
+				struct drm_agp_buffer *request)
+{
+	return -ENODEV;
+}
+
+static inline int drm_agp_free(struct drm_device *dev,
+			       struct drm_agp_buffer *request)
+{
+	return -ENODEV;
+}
+
+static inline int drm_agp_unbind(struct drm_device *dev,
+				 struct drm_agp_binding *request)
+{
+	return -ENODEV;
+}
+
+static inline int drm_agp_bind(struct drm_device *dev,
+			       struct drm_agp_binding *request)
+{
+	return -ENODEV;
+}
+
+#endif /* CONFIG_AGP */
+
+#endif /* _DRM_AGPSUPPORT_H_ */