Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/arm64/kernel/cacheinfo.c b/arch/arm64/kernel/cacheinfo.c
index 0bf0a83..7fa6828 100644
--- a/arch/arm64/kernel/cacheinfo.c
+++ b/arch/arm64/kernel/cacheinfo.c
@@ -1,20 +1,9 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  *  ARM64 cacheinfo support
  *
  *  Copyright (C) 2015 ARM Ltd.
  *  All Rights Reserved
- *
- * 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.
- *
- * This program is distributed "as is" WITHOUT ANY WARRANTY of any
- * kind, whether express or implied; without even the implied warranty
- * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
 #include <linux/acpi.h>
@@ -28,6 +17,15 @@
 #define CLIDR_CTYPE(clidr, level)	\
 	(((clidr) & CLIDR_CTYPE_MASK(level)) >> CLIDR_CTYPE_SHIFT(level))
 
+int cache_line_size(void)
+{
+	if (coherency_max_size != 0)
+		return coherency_max_size;
+
+	return cache_line_size_of_cpu();
+}
+EXPORT_SYMBOL_GPL(cache_line_size);
+
 static inline enum cache_type get_cache_type(int level)
 {
 	u64 clidr;