Linux kernel mirror (for testing)
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linux
1#ifndef __ASM_CRIS_SYSTEM_H
2#define __ASM_CRIS_SYSTEM_H
3
4#include <asm/arch/system.h>
5
6/* the switch_to macro calls resume, an asm function in entry.S which does the actual
7 * task switching.
8 */
9
10extern struct task_struct *resume(struct task_struct *prev, struct task_struct *next, int);
11#define prepare_to_switch() do { } while(0)
12#define switch_to(prev,next,last) last = resume(prev,next, \
13 (int)&((struct task_struct *)0)->thread)
14
15#define barrier() __asm__ __volatile__("": : :"memory")
16#define mb() barrier()
17#define rmb() mb()
18#define wmb() mb()
19#define read_barrier_depends() do { } while(0)
20#define set_mb(var, value) do { var = value; mb(); } while (0)
21#define set_wmb(var, value) do { var = value; wmb(); } while (0)
22
23#ifdef CONFIG_SMP
24#define smp_mb() mb()
25#define smp_rmb() rmb()
26#define smp_wmb() wmb()
27#define smp_read_barrier_depends() read_barrier_depends()
28#else
29#define smp_mb() barrier()
30#define smp_rmb() barrier()
31#define smp_wmb() barrier()
32#define smp_read_barrier_depends() do { } while(0)
33#endif
34
35#define iret()
36
37/*
38 * disable hlt during certain critical i/o operations
39 */
40#define HAVE_DISABLE_HLT
41void disable_hlt(void);
42void enable_hlt(void);
43
44static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int size)
45{
46 /* since Etrax doesn't have any atomic xchg instructions, we need to disable
47 irq's (if enabled) and do it with move.d's */
48 unsigned long flags,temp;
49 local_save_flags(flags); /* save flags, including irq enable bit */
50 local_irq_disable(); /* shut off irq's */
51 switch (size) {
52 case 1:
53 *((unsigned char *)&temp) = x;
54 x = *(unsigned char *)ptr;
55 *(unsigned char *)ptr = *((unsigned char *)&temp);
56 break;
57 case 2:
58 *((unsigned short *)&temp) = x;
59 x = *(unsigned short *)ptr;
60 *(unsigned short *)ptr = *((unsigned short *)&temp);
61 break;
62 case 4:
63 temp = x;
64 x = *(unsigned long *)ptr;
65 *(unsigned long *)ptr = temp;
66 break;
67 }
68 local_irq_restore(flags); /* restore irq enable bit */
69 return x;
70}
71
72#define arch_align_stack(x) (x)
73
74#endif