summaryrefslogtreecommitdiff
path: root/arch/frv/include/asm/system.h
blob: 0a6d8d9ca45bdbb6398b2ff2882203743963ea8b (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
/* 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/types.h>
#include <linux/linkage.h>
#include <linux/kernel.h>

struct thread_struct;

/*
 * 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)

/*
 * 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 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()
#define set_mb(var, value) \
	do { xchg(&var, (value)); } while (0)
#else
#define smp_mb()			barrier()
#define smp_rmb()			barrier()
#define smp_wmb()			barrier()
#define smp_read_barrier_depends()	do {} while(0)
#define set_mb(var, value) \
	do { var = (value); barrier(); } while (0)
#endif

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

#define arch_align_stack(x) (x)

/*****************************************************************************/
/*
 * compare and conditionally exchange value with memory
 * - if (*ptr == test) then orig = *ptr; *ptr = test;
 * - if (*ptr != test) then orig = *ptr;
 */
extern uint64_t __cmpxchg_64(uint64_t test, uint64_t new, volatile uint64_t *v);

#ifndef CONFIG_FRV_OUTOFLINE_ATOMIC_OPS

#define cmpxchg(ptr, test, new)							\
({										\
	__typeof__(ptr) __xg_ptr = (ptr);					\
	__typeof__(*(ptr)) __xg_orig, __xg_tmp;					\
	__typeof__(*(ptr)) __xg_test = (test);					\
	__typeof__(*(ptr)) __xg_new = (new);					\
										\
	switch (sizeof(__xg_orig)) {						\
	case 4:									\
		asm volatile(							\
			"0:						\n"	\
			"	orcc		gr0,gr0,gr0,icc3	\n"	\
			"	ckeq		icc3,cc7		\n"	\
			"	ld.p		%M0,%1			\n"	\
			"	orcr		cc7,cc7,cc3		\n"	\
			"	sub%I4cc	%1,%4,%2,icc0		\n"	\
			"	bne		icc0,#0,1f		\n"	\
			"	cst.p		%3,%M0		,cc3,#1	\n"	\
			"	corcc		gr29,gr29,gr0	,cc3,#1	\n"	\
			"	beq		icc3,#0,0b		\n"	\
			"1:						\n"	\
			: "+U"(*__xg_ptr), "=&r"(__xg_orig), "=&r"(__xg_tmp)	\
			: "r"(__xg_new), "NPr"(__xg_test)			\
			: "memory", "cc7", "cc3", "icc3", "icc0"		\
			);							\
		break;								\
										\
	default:								\
		__xg_orig = (__typeof__(__xg_orig))0;				\
		asm volatile("break");						\
		break;								\
	}									\
										\
	__xg_orig;								\
})

#else

extern uint32_t __cmpxchg_32(uint32_t *v, uint32_t test, uint32_t new);

#define cmpxchg(ptr, test, new)							\
({										\
	__typeof__(ptr) __xg_ptr = (ptr);					\
	__typeof__(*(ptr)) __xg_orig;						\
	__typeof__(*(ptr)) __xg_test = (test);					\
	__typeof__(*(ptr)) __xg_new = (new);					\
										\
	switch (sizeof(__xg_orig)) {						\
	case 4: __xg_orig = (__force __typeof__(*ptr))				\
			__cmpxchg_32((__force uint32_t *)__xg_ptr,		\
					 (__force uint32_t)__xg_test,		\
					 (__force uint32_t)__xg_new); break;	\
	default:								\
		__xg_orig = (__typeof__(__xg_orig))0;				\
		asm volatile("break");						\
		break;								\
	}									\
										\
	__xg_orig;								\
})

#endif

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

static inline unsigned long __cmpxchg_local(volatile void *ptr,
				      unsigned long old,
				      unsigned long new, int size)
{
	switch (size) {
	case 4:
		return cmpxchg((unsigned long *)ptr, old, new);
	default:
		return __cmpxchg_local_generic(ptr, old, new, size);
	}

	return old;
}

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

#endif /* _ASM_SYSTEM_H */