aboutsummaryrefslogtreecommitdiff
path: root/include/asm-blackfin/system.h
blob: b5bf6e7cb5e8caaae95ef37e70a610d1bf0daac5 (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
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
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
/*
 * 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/compiler.h>

/*
 * Interrupt configuring macros.
 */

extern unsigned long irq_flags;

#define local_irq_enable() do {		\
	__asm__ __volatile__ (		\
		"sti %0;"		\
		::"d"(irq_flags));	\
} while (0)

#define local_irq_disable() do {	\
	int _tmp_dummy;			\
	__asm__ __volatile__ (		\
		"cli %0;"		\
		:"=d" (_tmp_dummy):);	\
} while (0)

#if defined(ANOMALY_05000244) && defined (CONFIG_BLKFIN_CACHE)
#define idle_with_irq_disabled() do {   \
        __asm__ __volatile__ (          \
                "nop; nop;\n"           \
                ".align 8;\n"           \
                "sti %0; idle;\n"       \
                ::"d" (irq_flags));     \
} while (0)
#else
#define idle_with_irq_disabled() do {   \
	__asm__ __volatile__ (          \
		".align 8;\n"           \
		"sti %0; idle;\n"       \
		::"d" (irq_flags));     \
} while (0)
#endif

#ifdef CONFIG_DEBUG_HWERR
#define __save_and_cli(x) do {			\
	__asm__ __volatile__ (		        \
		"cli %0;\n\tsti %1;"		\
		:"=&d"(x): "d" (0x3F));		\
} while (0)
#else
#define __save_and_cli(x) do {		\
	__asm__ __volatile__ (          \
		"cli %0;"		\
		:"=&d"(x):);		\
} while (0)
#endif

#define local_save_flags(x) asm volatile ("cli %0;"     \
					  "sti %0;"     \
				    	  :"=d"(x):);

#ifdef CONFIG_DEBUG_HWERR
#define irqs_enabled_from_flags(x) (((x) & ~0x3f) != 0)
#else
#define irqs_enabled_from_flags(x) ((x) != 0x1f)
#endif

#define local_irq_restore(x) do {			\
	if (irqs_enabled_from_flags(x))			\
		local_irq_enable ();			\
} while (0)

/* For spinlocks etc */
#define local_irq_save(x) __save_and_cli(x)

#define	irqs_disabled()				\
({						\
	unsigned long flags;			\
	local_save_flags(flags);		\
	!irqs_enabled_from_flags(flags);	\
})

/*
 * 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_rmb(var, value)    do { (void) xchg(&var, value); } while (0)
#define set_mb(var, value)     set_rmb(var, value)
#define set_wmb(var, value)    do { var = value; wmb(); } while (0)

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

#ifdef CONFIG_SMP
#define smp_mb()	mb()
#define smp_rmb()	rmb()
#define smp_wmb()	wmb()
#define smp_read_barrier_depends()	read_barrier_depends()
#else
#define smp_mb()	barrier()
#define smp_rmb()	barrier()
#define smp_wmb()	barrier()
#define smp_read_barrier_depends()	do { } while(0)
#endif

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

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(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(flags);
	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 = 0;
	unsigned long flags = 0;

	local_irq_save(flags);

	switch (size) {
	case 1:
		__asm__ __volatile__
			("%0 = b%3 (z);\n\t"
			 "CC = %1 == %0;\n\t"
			 "IF !CC JUMP 1f;\n\t"
			 "b%3 = %2;\n\t"
			 "1:\n\t"
			 : "=&d" (tmp) : "d" (old), "d" (new), "m" (*__xg(ptr)) : "memory");
		break;
	case 2:
		__asm__ __volatile__
			("%0 = w%3 (z);\n\t"
			 "CC = %1 == %0;\n\t"
			 "IF !CC JUMP 1f;\n\t"
			 "w%3 = %2;\n\t"
			 "1:\n\t"
			 : "=&d" (tmp) : "d" (old), "d" (new), "m" (*__xg(ptr)) : "memory");
		break;
	case 4:
		__asm__ __volatile__
			("%0 = %3;\n\t"
			 "CC = %1 == %0;\n\t"
			 "IF !CC JUMP 1f;\n\t"
			 "%3 = %2;\n\t"
			 "1:\n\t"
			 : "=&d" (tmp) : "d" (old), "d" (new), "m" (*__xg(ptr)) : "memory");
		break;
	}
	local_irq_restore(flags);
	return tmp;
}

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

#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/blackfin.h>

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

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

#endif				/* _BLACKFIN_SYSTEM_H */