nds32: Library functions

This patch add support for various library functions.

Signed-off-by: Vincent Chen <vincentc@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>

1 files changed, 45 insertions, 0 deletions

diff --git a/arch/nds32/lib/copy_from_user.S b/arch/nds32/lib/copy_from_user.S
new file mode 100644
index 000000000000..ad1857b20067
--- /dev/null
+++ b/arch/nds32/lib/copy_from_user.S
@@ -0,0 +1,45 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2017 Andes Technology Corporation
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+#include <asm/errno.h>
+
+.macro 	lbi1 dst, addr, adj
+USER( lbi.bi, \dst, [\addr], \adj)
+.endm
+
+.macro 	sbi1 src, addr, adj
+sbi.bi	\src, [\addr], \adj
+.endm
+
+.macro	lmw1 start_reg, addr, end_reg
+USER( lmw.bim, \start_reg, [\addr], \end_reg)
+.endm
+
+.macro	smw1 start_reg, addr, end_reg
+smw.bim \start_reg, [\addr], \end_reg
+.endm
+
+
+/* Prototype: int __arch_copy_from_user(void *to, const char *from, size_t n)
+ * Purpose  : copy a block from user memory to kernel memory
+ * Params   : to   - kernel memory
+ *          : from - user memory
+ *          : n    - number of bytes to copy
+ * Returns  : Number of bytes NOT copied.
+ */
+
+.text
+ENTRY(__arch_copy_from_user)
+	add	$r5, $r0, $r2
+#include "copy_template.S"
+	move	$r0, $r2
+	ret
+.section .fixup,"ax"
+.align  2
+9001:
+	sub	$r0, $r5, $r0
+	ret
+.previous
+ENDPROC(__arch_copy_from_user)