Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/csky/mm/syscache.c b/arch/csky/mm/syscache.c
new file mode 100644
index 0000000..c4645e4
--- /dev/null
+++ b/arch/csky/mm/syscache.c
@@ -0,0 +1,32 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#include <linux/syscalls.h>
+#include <asm/page.h>
+#include <asm/cache.h>
+#include <asm/cachectl.h>
+
+SYSCALL_DEFINE3(cacheflush,
+ void __user *, addr,
+ unsigned long, bytes,
+ int, cache)
+{
+ switch (cache) {
+ case ICACHE:
+ icache_inv_range((unsigned long)addr,
+ (unsigned long)addr + bytes);
+ break;
+ case DCACHE:
+ dcache_wb_range((unsigned long)addr,
+ (unsigned long)addr + bytes);
+ break;
+ case BCACHE:
+ cache_wbinv_range((unsigned long)addr,
+ (unsigned long)addr + bytes);
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}