v4.19.13 snapshot.
diff --git a/arch/arm/mm/cache-nop.S b/arch/arm/mm/cache-nop.S
new file mode 100644
index 0000000..f1cc986
--- /dev/null
+++ b/arch/arm/mm/cache-nop.S
@@ -0,0 +1,51 @@
+/*
+ * 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/linkage.h>
+#include <linux/init.h>
+#include <asm/assembler.h>
+
+#include "proc-macros.S"
+
+ENTRY(nop_flush_icache_all)
+ ret lr
+ENDPROC(nop_flush_icache_all)
+
+ .globl nop_flush_kern_cache_all
+ .equ nop_flush_kern_cache_all, nop_flush_icache_all
+
+ .globl nop_flush_kern_cache_louis
+ .equ nop_flush_kern_cache_louis, nop_flush_icache_all
+
+ .globl nop_flush_user_cache_all
+ .equ nop_flush_user_cache_all, nop_flush_icache_all
+
+ .globl nop_flush_user_cache_range
+ .equ nop_flush_user_cache_range, nop_flush_icache_all
+
+ .globl nop_coherent_kern_range
+ .equ nop_coherent_kern_range, nop_flush_icache_all
+
+ENTRY(nop_coherent_user_range)
+ mov r0, 0
+ ret lr
+ENDPROC(nop_coherent_user_range)
+
+ .globl nop_flush_kern_dcache_area
+ .equ nop_flush_kern_dcache_area, nop_flush_icache_all
+
+ .globl nop_dma_flush_range
+ .equ nop_dma_flush_range, nop_flush_icache_all
+
+ .globl nop_dma_map_area
+ .equ nop_dma_map_area, nop_flush_icache_all
+
+ .globl nop_dma_unmap_area
+ .equ nop_dma_unmap_area, nop_flush_icache_all
+
+ __INITDATA
+
+ @ define struct cpu_cache_fns (see <asm/cacheflush.h> and proc-macros.S)
+ define_cache_functions nop