1 #ifndef _M68K_SEGMENT_H
2 #define _M68K_SEGMENT_H
3 
4 /* define constants */
5 /* Address spaces (FC0-FC2) */
6 #define USER_DATA     (1)
7 #ifndef __USER_DS
8 #define __USER_DS     (USER_DATA)
9 #endif
10 #define USER_PROGRAM  (2)
11 #define SUPER_DATA    (5)
12 #ifndef __KERNEL_DS
13 #define __KERNEL_DS   (SUPER_DATA)
14 #endif
15 #define SUPER_PROGRAM (6)
16 #define CPU_SPACE     (7)
17 
18 #ifndef __ASSEMBLY__
19 
20 typedef struct {
21 	unsigned long seg;
22 } mm_segment_t;
23 
24 #define MAKE_MM_SEG(s)	((mm_segment_t) { (s) })
25 #define USER_DS		MAKE_MM_SEG(__USER_DS)
26 #define KERNEL_DS	MAKE_MM_SEG(__KERNEL_DS)
27 
28 /*
29  * Get/set the SFC/DFC registers for MOVES instructions
30  */
31 
get_fs(void)32 static inline mm_segment_t get_fs(void)
33 {
34 #ifdef CONFIG_MMU
35 	mm_segment_t _v;
36 	__asm__ ("movec %/dfc,%0":"=r" (_v.seg):);
37 
38 	return _v;
39 #else
40 	return USER_DS;
41 #endif
42 }
43 
get_ds(void)44 static inline mm_segment_t get_ds(void)
45 {
46     /* return the supervisor data space code */
47     return KERNEL_DS;
48 }
49 
set_fs(mm_segment_t val)50 static inline void set_fs(mm_segment_t val)
51 {
52 #ifdef CONFIG_MMU
53 	__asm__ __volatile__ ("movec %0,%/sfc\n\t"
54 			      "movec %0,%/dfc\n\t"
55 			      : /* no outputs */ : "r" (val.seg) : "memory");
56 #endif
57 }
58 
59 #define segment_eq(a,b)	((a).seg == (b).seg)
60 
61 #endif /* __ASSEMBLY__ */
62 
63 #endif /* _M68K_SEGMENT_H */
64