Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/mips/kernel/prom.c b/arch/mips/kernel/prom.c
index 89950b7..9e50dc8 100644
--- a/arch/mips/kernel/prom.c
+++ b/arch/mips/kernel/prom.c
@@ -1,18 +1,15 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * MIPS support for CONFIG_OF device tree support
  *
  * Copyright (C) 2010 Cisco Systems Inc. <dediao@cisco.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
  */
 
 #include <linux/init.h>
 #include <linux/export.h>
 #include <linux/errno.h>
 #include <linux/types.h>
-#include <linux/bootmem.h>
+#include <linux/memblock.h>
 #include <linux/debugfs.h>
 #include <linux/of.h>
 #include <linux/of_fdt.h>
@@ -41,13 +38,27 @@
 #ifdef CONFIG_USE_OF
 void __init early_init_dt_add_memory_arch(u64 base, u64 size)
 {
-	return add_memory_region(base, size, BOOT_MEM_RAM);
+	if (base >= PHYS_ADDR_MAX) {
+		pr_warn("Trying to add an invalid memory region, skipped\n");
+		return;
+	}
+
+	/* Truncate the passed memory region instead of type casting */
+	if (base + size - 1 >= PHYS_ADDR_MAX || base + size < base) {
+		pr_warn("Truncate memory region %llx @ %llx to size %llx\n",
+			size, base, PHYS_ADDR_MAX - base);
+		size = PHYS_ADDR_MAX - base;
+	}
+
+	add_memory_region(base, size, BOOT_MEM_RAM);
 }
 
 int __init early_init_dt_reserve_memory_arch(phys_addr_t base,
 					phys_addr_t size, bool nomap)
 {
-	add_memory_region(base, size, BOOT_MEM_RESERVED);
+	add_memory_region(base, size,
+			  nomap ? BOOT_MEM_NOMAP : BOOT_MEM_RESERVED);
+
 	return 0;
 }