of/reserved_mem: Simplify the logic of fdt_scan_reserved_mem_reg_nodes()

Use the existing helper functions to simplify the logic of
fdt_scan_reserved_mem_reg_nodes()

Signed-off-by: Yuntao Wang <yuntao.wang@linux.dev>
Link: https://patch.msgid.link/20251115134753.179931-8-yuntao.wang@linux.dev
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>

Author: ytcoode

drivers/of/of_reserved_mem.c

@@ -225,12 +225,9 @@ static void __init __rmem_check_for_overlap(void);
  */
 void __init fdt_scan_reserved_mem_reg_nodes(void)
 {
-	int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
 	const void *fdt = initial_boot_params;
 	phys_addr_t base, size;
-	const __be32 *prop;
 	int node, child;
-	int len;
 
 	if (!fdt)
 		return;
@@ -251,29 +248,21 @@ void __init fdt_scan_reserved_mem_reg_nodes(void)
 
 	fdt_for_each_subnode(child, fdt, node) {
 		const char *uname;
+		u64 b, s;
 
-		prop = of_get_flat_dt_prop(child, "reg", &len);
-		if (!prop)
-			continue;
 		if (!of_fdt_device_is_available(fdt, child))
 			continue;
 
-		uname = fdt_get_name(fdt, child, NULL);
-		if (len && len % t_len != 0) {
-			pr_err("Reserved memory: invalid reg property in '%s', skipping node.\n",
-			       uname);
+		if (!of_flat_dt_get_addr_size(child, "reg", &b, &s))
 			continue;
-		}
-
-		if (len > t_len)
-			pr_warn("%s() ignores %d regions in node '%s'\n",
-				__func__, len / t_len - 1, uname);
 
-		base = dt_mem_next_cell(dt_root_addr_cells, &prop);
-		size = dt_mem_next_cell(dt_root_size_cells, &prop);
+		base = b;
+		size = s;
 
-		if (size)
+		if (size) {
+			uname = fdt_get_name(fdt, child, NULL);
 			fdt_reserved_mem_save_node(child, uname, base, size);
+		}
 	}
 
 	/* check for overlapping reserved regions */