Linux kernel mirror (for testing)
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1/* system.h: FR-V CPU control definitions
2 *
3 * Copyright (C) 2003 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 */
11
12#ifndef _ASM_SYSTEM_H
13#define _ASM_SYSTEM_H
14
15#include <linux/linkage.h>
16#include <asm/atomic.h>
17
18struct thread_struct;
19
20/*
21 * switch_to(prev, next) should switch from task `prev' to `next'
22 * `prev' will never be the same as `next'.
23 * The `mb' is to tell GCC not to cache `current' across this call.
24 */
25extern asmlinkage
26struct task_struct *__switch_to(struct thread_struct *prev_thread,
27 struct thread_struct *next_thread,
28 struct task_struct *prev);
29
30#define switch_to(prev, next, last) \
31do { \
32 (prev)->thread.sched_lr = \
33 (unsigned long) __builtin_return_address(0); \
34 (last) = __switch_to(&(prev)->thread, &(next)->thread, (prev)); \
35 mb(); \
36} while(0)
37
38/*
39 * interrupt flag manipulation
40 * - use virtual interrupt management since touching the PSR is slow
41 * - ICC2.Z: T if interrupts virtually disabled
42 * - ICC2.C: F if interrupts really disabled
43 * - if Z==1 upon interrupt:
44 * - C is set to 0
45 * - interrupts are really disabled
46 * - entry.S returns immediately
47 * - uses TIHI (TRAP if Z==0 && C==0) #2 to really reenable interrupts
48 * - if taken, the trap:
49 * - sets ICC2.C
50 * - enables interrupts
51 */
52#define local_irq_disable() \
53do { \
54 /* set Z flag, but don't change the C flag */ \
55 asm volatile(" andcc gr0,gr0,gr0,icc2 \n" \
56 : \
57 : \
58 : "memory", "icc2" \
59 ); \
60} while(0)
61
62#define local_irq_enable() \
63do { \
64 /* clear Z flag and then test the C flag */ \
65 asm volatile(" oricc gr0,#1,gr0,icc2 \n" \
66 " tihi icc2,gr0,#2 \n" \
67 : \
68 : \
69 : "memory", "icc2" \
70 ); \
71} while(0)
72
73#define local_save_flags(flags) \
74do { \
75 typecheck(unsigned long, flags); \
76 asm volatile("movsg ccr,%0" \
77 : "=r"(flags) \
78 : \
79 : "memory"); \
80 \
81 /* shift ICC2.Z to bit 0 */ \
82 flags >>= 26; \
83 \
84 /* make flags 1 if interrupts disabled, 0 otherwise */ \
85 flags &= 1UL; \
86} while(0)
87
88#define irqs_disabled() \
89 ({unsigned long flags; local_save_flags(flags); flags; })
90
91#define local_irq_save(flags) \
92do { \
93 typecheck(unsigned long, flags); \
94 local_save_flags(flags); \
95 local_irq_disable(); \
96} while(0)
97
98#define local_irq_restore(flags) \
99do { \
100 typecheck(unsigned long, flags); \
101 \
102 /* load the Z flag by turning 1 if disabled into 0 if disabled \
103 * and thus setting the Z flag but not the C flag */ \
104 asm volatile(" xoricc %0,#1,gr0,icc2 \n" \
105 /* then test Z=0 and C=0 */ \
106 " tihi icc2,gr0,#2 \n" \
107 : \
108 : "r"(flags) \
109 : "memory", "icc2" \
110 ); \
111 \
112} while(0)
113
114/*
115 * real interrupt flag manipulation
116 */
117#define __local_irq_disable() \
118do { \
119 unsigned long psr; \
120 asm volatile(" movsg psr,%0 \n" \
121 " andi %0,%2,%0 \n" \
122 " ori %0,%1,%0 \n" \
123 " movgs %0,psr \n" \
124 : "=r"(psr) \
125 : "i" (PSR_PIL_14), "i" (~PSR_PIL) \
126 : "memory"); \
127} while(0)
128
129#define __local_irq_enable() \
130do { \
131 unsigned long psr; \
132 asm volatile(" movsg psr,%0 \n" \
133 " andi %0,%1,%0 \n" \
134 " movgs %0,psr \n" \
135 : "=r"(psr) \
136 : "i" (~PSR_PIL) \
137 : "memory"); \
138} while(0)
139
140#define __local_save_flags(flags) \
141do { \
142 typecheck(unsigned long, flags); \
143 asm("movsg psr,%0" \
144 : "=r"(flags) \
145 : \
146 : "memory"); \
147} while(0)
148
149#define __local_irq_save(flags) \
150do { \
151 unsigned long npsr; \
152 typecheck(unsigned long, flags); \
153 asm volatile(" movsg psr,%0 \n" \
154 " andi %0,%3,%1 \n" \
155 " ori %1,%2,%1 \n" \
156 " movgs %1,psr \n" \
157 : "=r"(flags), "=r"(npsr) \
158 : "i" (PSR_PIL_14), "i" (~PSR_PIL) \
159 : "memory"); \
160} while(0)
161
162#define __local_irq_restore(flags) \
163do { \
164 typecheck(unsigned long, flags); \
165 asm volatile(" movgs %0,psr \n" \
166 : \
167 : "r" (flags) \
168 : "memory"); \
169} while(0)
170
171#define __irqs_disabled() \
172 ((__get_PSR() & PSR_PIL) >= PSR_PIL_14)
173
174/*
175 * Force strict CPU ordering.
176 */
177#define nop() asm volatile ("nop"::)
178#define mb() asm volatile ("membar" : : :"memory")
179#define rmb() asm volatile ("membar" : : :"memory")
180#define wmb() asm volatile ("membar" : : :"memory")
181#define set_mb(var, value) do { var = value; mb(); } while (0)
182
183#define smp_mb() mb()
184#define smp_rmb() rmb()
185#define smp_wmb() wmb()
186
187#define read_barrier_depends() do {} while(0)
188#define smp_read_barrier_depends() read_barrier_depends()
189
190#define HARD_RESET_NOW() \
191do { \
192 cli(); \
193} while(1)
194
195extern void die_if_kernel(const char *, ...) __attribute__((format(printf, 1, 2)));
196extern void free_initmem(void);
197
198#define arch_align_stack(x) (x)
199
200#endif /* _ASM_SYSTEM_H */