summaryrefslogtreecommitdiff
path: root/include/asm-frv/system.h
blob: f72ff0c4dc0b9050a580e0c4dba61b8a36b7b129 (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
/* system.h: FR-V CPU control definitions
 *
 * Copyright (C) 2003 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 *
 * 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 of the License, or (at your option) any later version.
 */

#ifndef _ASM_SYSTEM_H
#define _ASM_SYSTEM_H

#include <linux/config.h> /* get configuration macros */
#include <linux/linkage.h>
#include <asm/atomic.h>

struct thread_struct;

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

/*
 * switch_to(prev, next) should switch from task `prev' to `next'
 * `prev' will never be the same as `next'.
 * The `mb' is to tell GCC not to cache `current' across this call.
 */
extern asmlinkage
struct task_struct *__switch_to(struct thread_struct *prev_thread,
				struct thread_struct *next_thread,
				struct task_struct *prev);

#define switch_to(prev, next, last)					\
do {									\
	(prev)->thread.sched_lr =					\
		(unsigned long) __builtin_return_address(0);		\
	(last) = __switch_to(&(prev)->thread, &(next)->thread, (prev));	\
	mb();								\
} while(0)

/*
 * interrupt flag manipulation
 * - use virtual interrupt management since touching the PSR is slow
 *   - ICC2.Z: T if interrupts virtually disabled
 *   - ICC2.C: F if interrupts really disabled
 * - if Z==1 upon interrupt:
 *   - C is set to 0
 *   - interrupts are really disabled
 *   - entry.S returns immediately
 * - uses TIHI (TRAP if Z==0 && C==0) #2 to really reenable interrupts
 *   - if taken, the trap:
 *     - sets ICC2.C
 *     - enables interrupts
 */
#define local_irq_disable()					\
do {								\
	/* set Z flag, but don't change the C flag */		\
	asm volatile("	andcc	gr0,gr0,gr0,icc2	\n"	\
		     :						\
		     :						\
		     : "memory", "icc2"				\
		     );						\
} while(0)

#define local_irq_enable()					\
do {								\
	/* clear Z flag and then test the C flag */		\
	asm volatile("  oricc	gr0,#1,gr0,icc2		\n"	\
		     "	tihi	icc2,gr0,#2		\n"	\
		     :						\
		     :						\
		     : "memory", "icc2"				\
		     );						\
} while(0)

#define local_save_flags(flags)					\
do {								\
	typecheck(unsigned long, flags);			\
	asm volatile("movsg ccr,%0"				\
		     : "=r"(flags)				\
		     :						\
		     : "memory");				\
								\
	/* shift ICC2.Z to bit 0 */				\
	flags >>= 26;						\
								\
	/* make flags 1 if interrupts disabled, 0 otherwise */	\
	flags &= 1UL;						\
} while(0)

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

#define	local_irq_save(flags)			\
do {						\
	typecheck(unsigned long, flags);	\
	local_save_flags(flags);		\
	local_irq_disable();			\
} while(0)

#define	local_irq_restore(flags)					\
do {									\
	typecheck(unsigned long, flags);				\
									\
	/* load the Z flag by turning 1 if disabled into 0 if disabled	\
	 * and thus setting the Z flag but not the C flag */		\
	asm volatile("  xoricc	%0,#1,gr0,icc2		\n"		\
		     /* then test Z=0 and C=0 */			\
		     "	tihi	icc2,gr0,#2		\n"		\
		     :							\
		     : "r"(flags)					\
		     : "memory", "icc2"					\
		     );							\
									\
} while(0)

/*
 * real interrupt flag manipulation
 */
#define __local_irq_disable()				\
do {							\
	unsigned long psr;				\
	asm volatile("	movsg	psr,%0		\n"	\
		     "	andi	%0,%2,%0	\n"	\
		     "	ori	%0,%1,%0	\n"	\
		     "	movgs	%0,psr		\n"	\
		     : "=r"(psr)			\
		     : "i" (PSR_PIL_14), "i" (~PSR_PIL)	\
		     : "memory");			\
} while(0)

#define __local_irq_enable()				\
do {							\
	unsigned long psr;				\
	asm volatile("	movsg	psr,%0		\n"	\
		     "	andi	%0,%1,%0	\n"	\
		     "	movgs	%0,psr		\n"	\
		     : "=r"(psr)			\
		     : "i" (~PSR_PIL)			\
		     : "memory");			\
} while(0)

#define __local_save_flags(flags)		\
do {						\
	typecheck(unsigned long, flags);	\
	asm("movsg psr,%0"			\
	    : "=r"(flags)			\
	    :					\
	    : "memory");			\
} while(0)

#define	__local_irq_save(flags)				\
do {							\
	unsigned long npsr;				\
	typecheck(unsigned long, flags);		\
	asm volatile("	movsg	psr,%0		\n"	\
		     "	andi	%0,%3,%1	\n"	\
		     "	ori	%1,%2,%1	\n"	\
		     "	movgs	%1,psr		\n"	\
		     : "=r"(flags), "=r"(npsr)		\
		     : "i" (PSR_PIL_14), "i" (~PSR_PIL)	\
		     : "memory");			\
} while(0)

#define	__local_irq_restore(flags)			\
do {							\
	typecheck(unsigned long, flags);		\
	asm volatile("	movgs	%0,psr		\n"	\
		     :					\
		     : "r" (flags)			\
		     : "memory");			\
} while(0)

#define __irqs_disabled() \
	((__get_PSR() & PSR_PIL) >= PSR_PIL_14)

/*
 * Force strict CPU ordering.
 */
#define nop()			asm volatile ("nop"::)
#define mb()			asm volatile ("membar" : : :"memory")
#define rmb()			asm volatile ("membar" : : :"memory")
#define wmb()			asm volatile ("membar" : : :"memory")
#define set_mb(var, value)	do { var = value; mb(); } while (0)
#define set_wmb(var, value)	do { var = value; wmb(); } while (0)

#define smp_mb()		mb()
#define smp_rmb()		rmb()
#define smp_wmb()		wmb()

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

#define HARD_RESET_NOW()			\
do {						\
	cli();					\
} while(1)

extern void die_if_kernel(const char *, ...) __attribute__((format(printf, 1, 2)));
extern void free_initmem(void);

#define arch_align_stack(x) (x)

#endif /* _ASM_SYSTEM_H */