of/fdt: Simplify the logic of early_init_dt_scan_memory()

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

Signed-off-by: Yuntao Wang <yuntao.wang@linux.dev>
Link: https://patch.msgid.link/20251115134753.179931-6-yuntao.wang@linux.dev
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>

Author: ytcoode

drivers/of/fdt.c

@@ -1033,8 +1033,8 @@ int __init early_init_dt_scan_memory(void)
 
 	fdt_for_each_subnode(node, fdt, 0) {
 		const char *type = of_get_flat_dt_prop(node, "device_type", NULL);
-		const __be32 *reg, *endp;
-		int l;
+		const __be32 *reg;
+		int i, l;
 		bool hotpluggable;
 
 		/* We are scanning "memory" nodes only */
@@ -1044,23 +1044,21 @@ int __init early_init_dt_scan_memory(void)
 		if (!of_fdt_device_is_available(fdt, node))
 			continue;
 
-		reg = of_get_flat_dt_prop(node, "linux,usable-memory", &l);
+		reg = of_flat_dt_get_addr_size_prop(node, "linux,usable-memory", &l);
 		if (reg == NULL)
-			reg = of_get_flat_dt_prop(node, "reg", &l);
+			reg = of_flat_dt_get_addr_size_prop(node, "reg", &l);
 		if (reg == NULL)
 			continue;
 
-		endp = reg + (l / sizeof(__be32));
 		hotpluggable = of_get_flat_dt_prop(node, "hotpluggable", NULL);
 
-		pr_debug("memory scan node %s, reg size %d,\n",
+		pr_debug("memory scan node %s, reg {addr,size} entries %d,\n",
 			 fdt_get_name(fdt, node, NULL), l);
 
-		while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
+		for (i = 0; i < l; i++) {
 			u64 base, size;
 
-			base = dt_mem_next_cell(dt_root_addr_cells, &reg);
-			size = dt_mem_next_cell(dt_root_size_cells, &reg);
+			of_flat_dt_read_addr_size(reg, i, &base, &size);
 
 			if (size == 0)
 				continue;