C6X: headers
[linux-3.10.git] / arch / c6x / include / asm / uaccess.h
1 /*
2  *  Copyright (C) 2011 Texas Instruments Incorporated
3  *  Author: Mark Salter <msalter@redhat.com>
4  *
5  *  This program is free software; you can redistribute it and/or modify
6  *  it under the terms of the GNU General Public License version 2 as
7  *  published by the Free Software Foundation.
8  */
9 #ifndef _ASM_C6X_UACCESS_H
10 #define _ASM_C6X_UACCESS_H
11
12 #include <linux/types.h>
13 #include <linux/compiler.h>
14 #include <linux/string.h>
15
16 #ifdef CONFIG_ACCESS_CHECK
17 #define __access_ok _access_ok
18 #endif
19
20 /*
21  * __copy_from_user/copy_to_user are based on ones in asm-generic/uaccess.h
22  *
23  * C6X supports unaligned 32 and 64 bit loads and stores.
24  */
25 static inline __must_check long __copy_from_user(void *to,
26                 const void __user *from, unsigned long n)
27 {
28         u32 tmp32;
29         u64 tmp64;
30
31         if (__builtin_constant_p(n)) {
32                 switch (n) {
33                 case 1:
34                         *(u8 *)to = *(u8 __force *)from;
35                         return 0;
36                 case 4:
37                         asm volatile ("ldnw .d1t1 *%2,%0\n"
38                                       "nop  4\n"
39                                       "stnw .d1t1 %0,*%1\n"
40                                       : "=&a"(tmp32)
41                                       : "A"(to), "a"(from)
42                                       : "memory");
43                         return 0;
44                 case 8:
45                         asm volatile ("ldndw .d1t1 *%2,%0\n"
46                                       "nop   4\n"
47                                       "stndw .d1t1 %0,*%1\n"
48                                       : "=&a"(tmp64)
49                                       : "a"(to), "a"(from)
50                                       : "memory");
51                         return 0;
52                 default:
53                         break;
54                 }
55         }
56
57         memcpy(to, (const void __force *)from, n);
58         return 0;
59 }
60
61 static inline __must_check long __copy_to_user(void __user *to,
62                 const void *from, unsigned long n)
63 {
64         u32 tmp32;
65         u64 tmp64;
66
67         if (__builtin_constant_p(n)) {
68                 switch (n) {
69                 case 1:
70                         *(u8 __force *)to = *(u8 *)from;
71                         return 0;
72                 case 4:
73                         asm volatile ("ldnw .d1t1 *%2,%0\n"
74                                       "nop  4\n"
75                                       "stnw .d1t1 %0,*%1\n"
76                                       : "=&a"(tmp32)
77                                       : "a"(to), "a"(from)
78                                       : "memory");
79                         return 0;
80                 case 8:
81                         asm volatile ("ldndw .d1t1 *%2,%0\n"
82                                       "nop   4\n"
83                                       "stndw .d1t1 %0,*%1\n"
84                                       : "=&a"(tmp64)
85                                       : "a"(to), "a"(from)
86                                       : "memory");
87                         return 0;
88                 default:
89                         break;
90                 }
91         }
92
93         memcpy((void __force *)to, from, n);
94         return 0;
95 }
96
97 #define __copy_to_user   __copy_to_user
98 #define __copy_from_user __copy_from_user
99
100 extern int _access_ok(unsigned long addr, unsigned long size);
101 #ifdef CONFIG_ACCESS_CHECK
102 #define __access_ok _access_ok
103 #endif
104
105 #include <asm-generic/uaccess.h>
106
107 #endif /* _ASM_C6X_UACCESS_H */