nios2: Memory management

This patch contains the initialisation of the memory blocks, MMU
attributes and the memory map.

Signed-off-by: Ley Foon Tan <lftan@altera.com>

1 files changed, 163 insertions, 0 deletions

diff --git a/arch/nios2/mm/uaccess.c b/arch/nios2/mm/uaccess.c
new file mode 100644
index 000000000000..7663e156ff4f
--- /dev/null
+++ b/arch/nios2/mm/uaccess.c
@@ -0,0 +1,163 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2009, Wind River Systems Inc
+ * Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com
+ */
+
+#include <linux/export.h>
+#include <linux/uaccess.h>
+
+asm(".global	__copy_from_user\n"
+	"   .type __copy_from_user, @function\n"
+	"__copy_from_user:\n"
+	"   movi  r2,7\n"
+	"   mov   r3,r4\n"
+	"   bge   r2,r6,1f\n"
+	"   xor   r2,r4,r5\n"
+	"   andi  r2,r2,3\n"
+	"   movi  r7,3\n"
+	"   beq   r2,zero,4f\n"
+	"1: addi  r6,r6,-1\n"
+	"   movi  r2,-1\n"
+	"   beq   r6,r2,3f\n"
+	"   mov   r7,r2\n"
+	"2: ldbu  r2,0(r5)\n"
+	"   addi  r6,r6,-1\n"
+	"   addi  r5,r5,1\n"
+	"   stb   r2,0(r3)\n"
+	"   addi  r3,r3,1\n"
+	"   bne   r6,r7,2b\n"
+	"3:\n"
+	"   addi  r2,r6,1\n"
+	"   ret\n"
+	"13:mov   r2,r6\n"
+	"   ret\n"
+	"4: andi  r2,r4,1\n"
+	"   cmpeq r2,r2,zero\n"
+	"   beq   r2,zero,7f\n"
+	"5: andi  r2,r3,2\n"
+	"   beq   r2,zero,6f\n"
+	"9: ldhu  r2,0(r5)\n"
+	"   addi  r6,r6,-2\n"
+	"   addi  r5,r5,2\n"
+	"   sth   r2,0(r3)\n"
+	"   addi  r3,r3,2\n"
+	"6: bge   r7,r6,1b\n"
+	"10:ldw   r2,0(r5)\n"
+	"   addi  r6,r6,-4\n"
+	"   addi  r5,r5,4\n"
+	"   stw   r2,0(r3)\n"
+	"   addi  r3,r3,4\n"
+	"   br    6b\n"
+	"7: ldbu  r2,0(r5)\n"
+	"   addi  r6,r6,-1\n"
+	"   addi  r5,r5,1\n"
+	"   addi  r3,r4,1\n"
+	"   stb   r2,0(r4)\n"
+	"   br    5b\n"
+	".section __ex_table,\"a\"\n"
+	".word 2b,3b\n"
+	".word 9b,13b\n"
+	".word 10b,13b\n"
+	".word 7b,13b\n"
+	".previous\n"
+	);
+EXPORT_SYMBOL(__copy_from_user);
+
+asm(
+	"   .global __copy_to_user\n"
+	"   .type __copy_to_user, @function\n"
+	"__copy_to_user:\n"
+	"   movi  r2,7\n"
+	"   mov   r3,r4\n"
+	"   bge   r2,r6,1f\n"
+	"   xor   r2,r4,r5\n"
+	"   andi  r2,r2,3\n"
+	"   movi  r7,3\n"
+	"   beq   r2,zero,4f\n"
+	/* Bail if we try to copy zero bytes  */
+	"1: addi  r6,r6,-1\n"
+	"   movi  r2,-1\n"
+	"   beq   r6,r2,3f\n"
+	/* Copy byte by byte for small copies and if src^dst != 0 */
+	"   mov   r7,r2\n"
+	"2: ldbu  r2,0(r5)\n"
+	"   addi  r5,r5,1\n"
+	"9: stb   r2,0(r3)\n"
+	"   addi  r6,r6,-1\n"
+	"   addi  r3,r3,1\n"
+	"   bne   r6,r7,2b\n"
+	"3: addi  r2,r6,1\n"
+	"   ret\n"
+	"13:mov   r2,r6\n"
+	"   ret\n"
+	/*  If 'to' is an odd address byte copy */
+	"4: andi  r2,r4,1\n"
+	"   cmpeq r2,r2,zero\n"
+	"   beq   r2,zero,7f\n"
+	/* If 'to' is not divideable by four copy halfwords */
+	"5: andi  r2,r3,2\n"
+	"   beq   r2,zero,6f\n"
+	"   ldhu  r2,0(r5)\n"
+	"   addi  r5,r5,2\n"
+	"10:sth   r2,0(r3)\n"
+	"   addi  r6,r6,-2\n"
+	"   addi  r3,r3,2\n"
+	/* Copy words */
+	"6: bge   r7,r6,1b\n"
+	"   ldw   r2,0(r5)\n"
+	"   addi  r5,r5,4\n"
+	"11:stw   r2,0(r3)\n"
+	"   addi  r6,r6,-4\n"
+	"   addi  r3,r3,4\n"
+	"   br    6b\n"
+	/* Copy remaining bytes */
+	"7: ldbu  r2,0(r5)\n"
+	"   addi  r5,r5,1\n"
+	"   addi  r3,r4,1\n"
+	"12: stb  r2,0(r4)\n"
+	"   addi  r6,r6,-1\n"
+	"   br    5b\n"
+	".section __ex_table,\"a\"\n"
+	".word 9b,3b\n"
+	".word 10b,13b\n"
+	".word 11b,13b\n"
+	".word 12b,13b\n"
+	".previous\n");
+EXPORT_SYMBOL(__copy_to_user);
+
+long strncpy_from_user(char *__to, const char __user *__from, long __len)
+{
+	int l = strnlen_user(__from, __len);
+	int is_zt = 1;
+
+	if (l > __len) {
+		is_zt = 0;
+		l = __len;
+	}
+
+	if (l == 0 || copy_from_user(__to, __from, l))
+		return -EFAULT;
+
+	if (is_zt)
+		l--;
+	return l;
+}
+
+long strnlen_user(const char __user *s, long n)
+{
+	long i;
+
+	for (i = 0; i < n; i++) {
+		char c;
+
+		if (get_user(c, s + i) == -EFAULT)
+			return 0;
+		if (c == 0)
+			return i + 1;
+	}
+	return n + 1;
+}