aboutsummaryrefslogtreecommitdiff
path: root/arch/microblaze/include/asm/system.h
blob: 3107748d3bdbf48c5428c28d3b0b53d133b03352 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
/*
 * include/asm-microblaze/system.h -- Low-level interrupt/thread ops
 *
 *  Copyright (C) 2003	John Williams (jwilliams@itee.uq.edu.au)
 *			based upon microblaze version
 *  Copyright (C) 2001	NEC Corporation
 *  Copyright (C) 2001	Miles Bader <miles@gnu.org>
 *
 * 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.
 *
 * Written by Miles Bader <miles@gnu.org>
 * Microblaze port by John Williams
 * Microblaze port by John Williams
 */

#ifndef __MICROBLAZE_SYSTEM_H__
#define __MICROBLAZE_SYSTEM_H__

#if 0
#include <linux/linkage.h>
#endif
#include <asm/ptrace.h>

#define prepare_to_switch()	do { } while (0)

/*
 * switch_to(n) should switch tasks to task ptr, first checking that
 * ptr isn't the current task, in which case it does nothing.
 */
struct thread_struct;
extern void *switch_thread (struct thread_struct *last,
			    struct thread_struct *next);
#define switch_to(prev,next,last) do {					\
	if (prev != next) {						\
		(last) = switch_thread (&prev->thread, &next->thread);	\
	}								\
} while (0)


/* Enable/disable interrupts.  */
#define __sti() \
{								\
	register unsigned tmp;					\
	__asm__ __volatile__ ("					\
			mfs	%0, rmsr;			\
			ori	%0, %0, 2;			\
			mts	rmsr, %0"			\
			: "=r" (tmp)				\
			:					\
			: "memory");				\
}

#define __cli() \
{								\
	register unsigned tmp;					\
	__asm__ __volatile__ ("					\
			mfs	%0, rmsr;			\
			andi	%0, %0, ~2;			\
			mts	rmsr, %0"			\
			: "=r" (tmp)				\
			:					\
			: "memory");				\
}

#define __save_flags(flags) \
	__asm__ __volatile__ ("mfs	%0, rmsr" : "=r" (flags))
#define __restore_flags(flags) \
	__asm__ __volatile__ ("mts	rmsr, %0" :: "r" (flags))

#define __save_flags_cli(flags) \
{								\
	register unsigned tmp;					\
	__asm__ __volatile__ ("					\
			mfs	%0, rmsr;			\
			andi	%1, %0, ~2;			\
			mts	rmsr, %1;"			\
			: "=r" (flags), "=r" (tmp)		\
			:					\
			: "memory");				\
}

#define __save_flags_sti(flags)					\
{								\
	register unsigned tmp;					\
	__asm__ __volatile__ ("					\
			mfs	%0, rmsr;			\
			ori	%1, %0, 2;			\
			mts	rmsr, %1;"			\
			: "=r" (flags) ,"=r" (tmp)		\
			:					\
			: "memory");				\
}

/* For spinlocks etc */
#define local_irq_save(flags)	__save_flags_cli (flags)
#define local_irq_set(flags)	__save_flags_sti (flags)
#define local_irq_restore(flags) __restore_flags (flags)
#define local_irq_disable()	__cli ()
#define local_irq_enable()	__sti ()

#define cli()			__cli ()
#define sti()			__sti ()
#define save_flags(flags)	__save_flags (flags)
#define restore_flags(flags)	__restore_flags (flags)
#define save_flags_cli(flags)	__save_flags_cli (flags)

/*
 * Force strict CPU ordering.
 * Not really required on microblaze...
 */
#define nop()			__asm__ __volatile__ ("nop")
#define mb()			__asm__ __volatile__ ("nop" ::: "memory")
#define rmb()			mb ()
#define wmb()			mb ()
#define set_mb(var, value)	do { var = value; mb(); } while (0)
#define set_wmb(var, value)	do { var = value; wmb (); } while (0)

#ifdef CONFIG_SMP
#define smp_mb()	mb ()
#define smp_rmb()	rmb ()
#define smp_wmb()	wmb ()
#else
#define smp_mb()	barrier ()
#define smp_rmb()	barrier ()
#define smp_wmb()	barrier ()
#endif

#define xchg(ptr, with) \
  ((__typeof__ (*(ptr)))__xchg ((unsigned long)(with), (ptr), sizeof (*(ptr))))
#define tas(ptr) (xchg ((ptr), 1))

static inline unsigned long __xchg(unsigned long with,
				    __volatile__ void *ptr, int size)
{
	unsigned long tmp, flags;

	save_flags_cli (flags);

	switch (size) {
	case 1:
		tmp = *(unsigned char *)ptr;
		*(unsigned char *)ptr = with;
		break;
	case 2:
		tmp = *(unsigned short *)ptr;
		*(unsigned short *)ptr = with;
		break;
	case 4:
		tmp = *(unsigned long *)ptr;
		*(unsigned long *)ptr = with;
		break;
	}

	restore_flags (flags);

	return tmp;
}

#endif /* __MICROBLAZE_SYSTEM_H__ */