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 */
__copy_from_user(void * to,const void __user * from,unsigned long n)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
__copy_to_user(void __user * to,const void * from,unsigned long n)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 */
108