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>
diff --git a/arch/nios2/mm/uaccess.c b/arch/nios2/mm/uaccess.c
new file mode 100644
index 0000000..7663e15
--- /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;
+}