v4.19.13 snapshot.
diff --git a/include/linux/of_reserved_mem.h b/include/linux/of_reserved_mem.h
new file mode 100644
index 0000000..67ab8d2
--- /dev/null
+++ b/include/linux/of_reserved_mem.h
@@ -0,0 +1,81 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __OF_RESERVED_MEM_H
+#define __OF_RESERVED_MEM_H
+
+#include <linux/device.h>
+
+struct of_phandle_args;
+struct reserved_mem_ops;
+
+struct reserved_mem {
+ const char *name;
+ unsigned long fdt_node;
+ unsigned long phandle;
+ const struct reserved_mem_ops *ops;
+ phys_addr_t base;
+ phys_addr_t size;
+ void *priv;
+};
+
+struct reserved_mem_ops {
+ int (*device_init)(struct reserved_mem *rmem,
+ struct device *dev);
+ void (*device_release)(struct reserved_mem *rmem,
+ struct device *dev);
+};
+
+typedef int (*reservedmem_of_init_fn)(struct reserved_mem *rmem);
+
+#define RESERVEDMEM_OF_DECLARE(name, compat, init) \
+ _OF_DECLARE(reservedmem, name, compat, init, reservedmem_of_init_fn)
+
+#ifdef CONFIG_OF_RESERVED_MEM
+
+int of_reserved_mem_device_init_by_idx(struct device *dev,
+ struct device_node *np, int idx);
+void of_reserved_mem_device_release(struct device *dev);
+
+int early_init_dt_alloc_reserved_memory_arch(phys_addr_t size,
+ phys_addr_t align,
+ phys_addr_t start,
+ phys_addr_t end,
+ bool nomap,
+ phys_addr_t *res_base);
+
+void fdt_init_reserved_mem(void);
+void fdt_reserved_mem_save_node(unsigned long node, const char *uname,
+ phys_addr_t base, phys_addr_t size);
+struct reserved_mem *of_reserved_mem_lookup(struct device_node *np);
+#else
+static inline int of_reserved_mem_device_init_by_idx(struct device *dev,
+ struct device_node *np, int idx)
+{
+ return -ENOSYS;
+}
+static inline void of_reserved_mem_device_release(struct device *pdev) { }
+
+static inline void fdt_init_reserved_mem(void) { }
+static inline void fdt_reserved_mem_save_node(unsigned long node,
+ const char *uname, phys_addr_t base, phys_addr_t size) { }
+static inline struct reserved_mem *of_reserved_mem_lookup(struct device_node *np)
+{
+ return NULL;
+}
+#endif
+
+/**
+ * of_reserved_mem_device_init() - assign reserved memory region to given device
+ * @dev: Pointer to the device to configure
+ *
+ * This function assigns respective DMA-mapping operations based on the first
+ * reserved memory region specified by 'memory-region' property in device tree
+ * node of the given device.
+ *
+ * Returns error code or zero on success.
+ */
+static inline int of_reserved_mem_device_init(struct device *dev)
+{
+ return of_reserved_mem_device_init_by_idx(dev, dev->of_node, 0);
+}
+
+#endif /* __OF_RESERVED_MEM_H */