diff --git a/mm/Kconfig b/mm/Kconfig
index 477b5eeca511..db74af09fe6d 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -63,6 +63,13 @@ config SPARSEMEM_MANUAL
 
 endchoice
 
+config MEMBLOCK_DEBUGFS
+	bool "Memblock debugfs for reserved memory"
+	depends on DEBUG_FS && ARCH_KEEP_MEMBLOCK
+	help
+	  Extend memblock debugfs to show size of each memblock, and shows the
+	  result of total size by KiB format.
+
 config DISCONTIGMEM
 	def_bool y
 	depends on (!SELECT_MEMORY_MODEL && ARCH_DISCONTIGMEM_ENABLE) || DISCONTIGMEM_MANUAL
diff --git a/mm/Makefile b/mm/Makefile
index d072cadb4299..d1a819711e9f 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -62,6 +62,7 @@ CFLAGS_page_alloc.o += -DDYNAMIC_DEBUG_MODULE
 obj-y += page-alloc.o
 obj-y += init-mm.o
 obj-y += memblock.o
+obj-$(CONFIG_MEMBLOCK_DEBUGFS) += memblock_debugfs.o
 
 ifdef CONFIG_MMU
 	obj-$(CONFIG_ADVISE_SYSCALLS)	+= madvise.o
diff --git a/mm/memblock_debugfs.c b/mm/memblock_debugfs.c
new file mode 100644
index 000000000000..4ee5d1de4add
--- /dev/null
+++ b/mm/memblock_debugfs.c
@@ -0,0 +1,52 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Debugfs for reserved memory blocks.
+ *
+ * Copyright (C) 2022 Rockchip Electronics Co. Ltd.
+ */
+
+#include <linux/init.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+#include <linux/memblock.h>
+
+#define K(size) ((unsigned long)((size) >> 10))
+
+static int memblock_debugfs_show(struct seq_file *m, void *private)
+{
+	struct memblock_type *type = m->private;
+	struct memblock_region *reg;
+	int i;
+	phys_addr_t end;
+	unsigned long z = 0, t = 0;
+
+	for (i = 0; i < type->cnt; i++) {
+		reg = &type->regions[i];
+		end = reg->base + reg->size - 1;
+		z = (unsigned long)reg->size;
+		t += z;
+
+		seq_printf(m, "%4d: ", i);
+		seq_printf(m, "%pa..%pa (%10lu %s)\n", &reg->base, &end,
+			   (z >= 1024) ? (K(z)) : z,
+			   (z >= 1024) ? "KiB" : "Bytes");
+	}
+	seq_printf(m, "Total: %lu KiB\n", K(t));
+
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(memblock_debugfs);
+
+static int __init memblock_debugfs_init(void)
+{
+	struct dentry *root = debugfs_lookup("memblock", NULL);
+
+	if (!root)
+		return -EPROBE_DEFER;
+
+	debugfs_create_file("reserved_size", 0444, root,
+			    &memblock.reserved, &memblock_debugfs_fops);
+
+	return 0;
+}
+late_initcall(memblock_debugfs_init);