aboutsummaryrefslogtreecommitdiffstats
path: root/arch/blackfin/include/asm/system.h
blob: 294dbda24164c442beea46664f8133c9c6bba85d (plain) (blame)
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
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
/*
 * File:        include/asm/system.h
 * Based on:
 * Author:      Tony Kou (tonyko@lineo.ca)
 *              Copyright (c) 2002 Arcturus Networks Inc.
 *                    (www.arcturusnetworks.com)
 *              Copyright (c) 2003 Metrowerks (www.metrowerks.com)
 *              Copyright (c) 2004 Analog Device Inc.
 * Created:     25Jan2001 - Tony Kou
 * Description: system.h include file
 *
 * Modified:     22Sep2006 - Robin Getz
 *                - move include blackfin.h down, so I can get access to
 *                   irq functions in other include files.
 *
 * Bugs:         Enter bugs at http://blackfin.uclinux.org/
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; see the file COPYING.
 * If not, write to the Free Software Foundation,
 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

#ifndef _BLACKFIN_SYSTEM_H
#define _BLACKFIN_SYSTEM_H

#include <linux/linkage.h>
#include <linux/irqflags.h>
#include <mach/anomaly.h>
#include <asm/cache.h>
#include <asm/pda.h>
#include <asm/irq.h>

/*
 * Force strict CPU ordering.
 */
#define nop()  __asm__ __volatile__ ("nop;\n\t" : : )
#define mb()   __asm__ __volatile__ (""   : : : "memory")
#define rmb()  __asm__ __volatile__ (""   : : : "memory")
#define wmb()  __asm__ __volatile__ (""   : : : "memory")
#define set_mb(var, value) do { (void) xchg(&var, value); } while (0)
#define read_barrier_depends() 		do { } while(0)

#ifdef CONFIG_SMP
asmlinkage unsigned long __raw_xchg_1_asm(volatile void *ptr, unsigned long value);
asmlinkage unsigned long __raw_xchg_2_asm(volatile void *ptr, unsigned long value);
asmlinkage unsigned long __raw_xchg_4_asm(volatile void *ptr, unsigned long value);
asmlinkage unsigned long __raw_cmpxchg_1_asm(volatile void *ptr,
					unsigned long new, unsigned long old);
asmlinkage unsigned long __raw_cmpxchg_2_asm(volatile void *ptr,
					unsigned long new, unsigned long old);
asmlinkage unsigned long __raw_cmpxchg_4_asm(volatile void *ptr,
					unsigned long new, unsigned long old);

#ifdef __ARCH_SYNC_CORE_DCACHE
# define smp_mb()	do { barrier(); smp_check_barrier(); smp_mark_barrier(); } while (0)
# define smp_rmb()	do { barrier(); smp_check_barrier(); } while (0)
# define smp_wmb()	do { barrier(); smp_mark_barrier(); } while (0)
#define smp_read_barrier_depends()	do { barrier(); smp_check_barrier(); } while (0)

#else
# define smp_mb()	barrier()
# define smp_rmb()	barrier()
# define smp_wmb()	barrier()
#define smp_read_barrier_depends()	barrier()
#endif

static inline unsigned long __xchg(unsigned long x, volatile void *ptr,
				   int size)
{
	unsigned long tmp;

	switch (size) {
	case 1:
		tmp = __raw_xchg_1_asm(ptr, x);
		break;
	case 2:
		tmp = __raw_xchg_2_asm(ptr, x);
		break;
	case 4:
		tmp = __raw_xchg_4_asm(ptr, x);
		break;
	}

	return tmp;
}

/*
 * Atomic compare and exchange.  Compare OLD with MEM, if identical,
 * store NEW in MEM.  Return the initial value in MEM.  Success is
 * indicated by comparing RETURN with OLD.
 */
static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old,
				      unsigned long new, int size)
{
	unsigned long tmp;

	switch (size) {
	case 1:
		tmp = __raw_cmpxchg_1_asm(ptr, new, old);
		break;
	case 2:
		tmp = __raw_cmpxchg_2_asm(ptr, new, old);
		break;
	case 4:
		tmp = __raw_cmpxchg_4_asm(ptr, new, old);
		break;
	}

	return tmp;
}
#define cmpxchg(ptr, o, n) \
	((__typeof__(*(ptr)))__cmpxchg((ptr), (unsigned long)(o), \
		(unsigned long)(n), sizeof(*(ptr))))

#else /* !CONFIG_SMP */

#define smp_mb()	barrier()
#define smp_rmb()	barrier()
#define smp_wmb()	barrier()
#define smp_read_barrier_depends()	do { } while(0)

struct __xchg_dummy {
	unsigned long a[100];
};
#define __xg(x) ((volatile struct __xchg_dummy *)(x))

static inline unsigned long __xchg(unsigned long x, volatile void *ptr,
				   int size)
{
	unsigned long tmp = 0;
	unsigned long flags = 0;

	local_irq_save_hw(flags);

	switch (size) {
	case 1:
		__asm__ __volatile__
			("%0 = b%2 (z);\n\t"
			 "b%2 = %1;\n\t"
			 : "=&d" (tmp) : "d" (x), "m" (*__xg(ptr)) : "memory");
		break;
	case 2:
		__asm__ __volatile__
			("%0 = w%2 (z);\n\t"
			 "w%2 = %1;\n\t"
			 : "=&d" (tmp) : "d" (x), "m" (*__xg(ptr)) : "memory");
		break;
	case 4:
		__asm__ __volatile__
			("%0 = %2;\n\t"
			 "%2 = %1;\n\t"
			 : "=&d" (tmp) : "d" (x), "m" (*__xg(ptr)) : "memory");
		break;
	}
	local_irq_restore_hw(flags);
	return tmp;
}

#include <asm-generic/cmpxchg-local.h>

/*
 * cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make
 * them available.
 */
#define cmpxchg_local(ptr, o, n)				  	       \
	((__typeof__(*(ptr)))__cmpxchg_local_generic((ptr), (unsigned long)(o),\
			(unsigned long)(n), sizeof(*(ptr))))
#define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n))

#include <asm-generic/cmpxchg.h>

#endif /* !CONFIG_SMP */

#define xchg(ptr, x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x), (ptr), sizeof(*(ptr))))
#define tas(ptr) ((void)xchg((ptr), 1))

#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.
 */

#include <asm/l1layout.h>
#include <asm/mem_map.h>

asmlinkage struct task_struct *resume(struct task_struct *prev, struct task_struct *next);

#ifndef CONFIG_SMP
#define switch_to(prev,next,last) \
do {    \
	memcpy (&task_thread_info(prev)->l1_task_info, L1_SCRATCH_TASK_INFO, \
		sizeof *L1_SCRATCH_TASK_INFO); \
	memcpy (L1_SCRATCH_TASK_INFO, &task_thread_info(next)->l1_task_info, \
		sizeof *L1_SCRATCH_TASK_INFO); \
	(last) = resume (prev, next);   \
} while (0)
#else
#define switch_to(prev, next, last) \
do {    \
	(last) = resume(prev, next);   \
} while (0)
#endif

#endif	/* _BLACKFIN_SYSTEM_H */