1 files changed, 101 insertions, 0 deletions
diff --git a/arch/openrisc/lib/string.S b/arch/openrisc/lib/string.S
new file mode 100644
index 000000000..74046f2eb
--- /dev/null
+++ b/arch/openrisc/lib/string.S
@@ -0,0 +1,101 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * OpenRISC string.S
+ *
+ * Linux architectural port borrowing liberally from similar works of
+ * others.  All original copyrights apply as per the original source
+ * declaration.
+ *
+ * Modifications for the OpenRISC architecture:
+ * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
+ * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
+ */
+
+#include <linux/linkage.h>
+#include <asm/errno.h>
+
+	/*
+	 * this can be optimized by doing gcc inline assemlby with
+	 * proper constraints (no need to save args registers...)
+	 *
+	 */
+
+
+/*
+ *
+ * int __copy_tofrom_user(void *to, const void *from, unsigned long size);
+ *
+ * NOTE: it returns number of bytes NOT copied !!!
+ *
+ */
+	.global	__copy_tofrom_user
+__copy_tofrom_user:
+	l.addi  r1,r1,-12
+	l.sw    0(r1),r6
+	l.sw    4(r1),r4
+	l.sw    8(r1),r3
+
+	l.addi  r11,r5,0
+2:  	l.sfeq  r11,r0
+	l.bf    1f
+	l.addi  r11,r11,-1
+8:    	l.lbz   r6,0(r4)
+9:    	l.sb    0(r3),r6
+	l.addi  r3,r3,1
+	l.j     2b
+	l.addi  r4,r4,1
+1:
+	l.addi  r11,r11,1               // r11 holds the return value
+
+	l.lwz   r6,0(r1)
+	l.lwz   r4,4(r1)
+	l.lwz   r3,8(r1)
+	l.jr    r9
+	l.addi  r1,r1,12
+
+	.section .fixup, "ax"
+99:
+		l.j     1b
+		l.nop
+	.previous
+
+	.section __ex_table, "a"
+		.long 8b, 99b		// read fault
+		.long 9b, 99b		// write fault
+	.previous
+
+/*
+ * unsigned long clear_user(void *addr, unsigned long size) ;
+ *
+ * NOTE: it returns number of bytes NOT cleared !!!
+ */
+	.global	__clear_user
+__clear_user:
+	l.addi  r1,r1,-8
+	l.sw    0(r1),r4
+	l.sw    4(r1),r3
+
+2:	l.sfeq	r4,r0
+	l.bf	1f
+	l.addi	r4,r4,-1
+9:	l.sb	0(r3),r0
+	l.j	2b
+	l.addi  r3,r3,1
+
+1:
+	l.addi  r11,r4,1
+
+	l.lwz	r4,0(r1)
+	l.lwz	r3,4(r1)
+	l.jr	r9
+	l.addi	r1,r1,8
+
+	.section .fixup, "ax"
+99:
+		l.j     1b
+		l.nop
+	.previous
+
+	.section __ex_table, "a"
+		.long 9b, 99b		// write fault
+	.previous