1 /*
2  *  arch/arm/include/asm/thread_info.h
3  *
4  *  Copyright (C) 2002 Russell King.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  */
10 #ifndef __ASM_ARM_THREAD_INFO_H
11 #define __ASM_ARM_THREAD_INFO_H
12 
13 #ifdef __KERNEL__
14 
15 #include <linux/compiler.h>
16 #include <asm/fpstate.h>
17 
18 #define THREAD_SIZE_ORDER	1
19 #define THREAD_SIZE		8192
20 #define THREAD_START_SP		(THREAD_SIZE - 8)
21 
22 #ifndef __ASSEMBLY__
23 
24 struct task_struct;
25 struct exec_domain;
26 
27 #include <asm/types.h>
28 #include <asm/domain.h>
29 
30 typedef unsigned long mm_segment_t;
31 
32 struct cpu_context_save {
33 	__u32	r4;
34 	__u32	r5;
35 	__u32	r6;
36 	__u32	r7;
37 	__u32	r8;
38 	__u32	r9;
39 	__u32	sl;
40 	__u32	fp;
41 	__u32	sp;
42 	__u32	pc;
43 	__u32	extra[2];		/* Xscale 'acc' register, etc */
44 };
45 
46 /*
47  * low level task data that entry.S needs immediate access to.
48  * __switch_to() assumes cpu_context follows immediately after cpu_domain.
49  */
50 struct thread_info {
51 	unsigned long		flags;		/* low level flags */
52 	int			preempt_count;	/* 0 => preemptable, <0 => bug */
53 	mm_segment_t		addr_limit;	/* address limit */
54 	struct task_struct	*task;		/* main task structure */
55 	struct exec_domain	*exec_domain;	/* execution domain */
56 	__u32			cpu;		/* cpu */
57 	__u32			cpu_domain;	/* cpu domain */
58 	struct cpu_context_save	cpu_context;	/* cpu context */
59 	__u32			syscall;	/* syscall number */
60 	__u8			used_cp[16];	/* thread used copro */
61 	unsigned long		tp_value;
62 	struct crunch_state	crunchstate;
63 	union fp_state		fpstate __attribute__((aligned(8)));
64 	union vfp_state		vfpstate;
65 #ifdef CONFIG_ARM_THUMBEE
66 	unsigned long		thumbee_state;	/* ThumbEE Handler Base register */
67 #endif
68 	struct restart_block	restart_block;
69 };
70 
71 #define INIT_THREAD_INFO(tsk)						\
72 {									\
73 	.task		= &tsk,						\
74 	.exec_domain	= &default_exec_domain,				\
75 	.flags		= 0,						\
76 	.preempt_count	= INIT_PREEMPT_COUNT,				\
77 	.addr_limit	= KERNEL_DS,					\
78 	.cpu_domain	= domain_val(DOMAIN_USER, DOMAIN_MANAGER) |	\
79 			  domain_val(DOMAIN_KERNEL, DOMAIN_MANAGER) |	\
80 			  domain_val(DOMAIN_IO, DOMAIN_CLIENT),		\
81 	.restart_block	= {						\
82 		.fn	= do_no_restart_syscall,			\
83 	},								\
84 }
85 
86 #define init_thread_info	(init_thread_union.thread_info)
87 #define init_stack		(init_thread_union.stack)
88 
89 /*
90  * how to get the thread information struct from C
91  */
92 static inline struct thread_info *current_thread_info(void) __attribute_const__;
93 
current_thread_info(void)94 static inline struct thread_info *current_thread_info(void)
95 {
96 	register unsigned long sp asm ("sp");
97 	return (struct thread_info *)(sp & ~(THREAD_SIZE - 1));
98 }
99 
100 #define thread_saved_pc(tsk)	\
101 	((unsigned long)(task_thread_info(tsk)->cpu_context.pc))
102 #define thread_saved_sp(tsk)	\
103 	((unsigned long)(task_thread_info(tsk)->cpu_context.sp))
104 #define thread_saved_fp(tsk)	\
105 	((unsigned long)(task_thread_info(tsk)->cpu_context.fp))
106 
107 extern void crunch_task_disable(struct thread_info *);
108 extern void crunch_task_copy(struct thread_info *, void *);
109 extern void crunch_task_restore(struct thread_info *, void *);
110 extern void crunch_task_release(struct thread_info *);
111 
112 extern void iwmmxt_task_disable(struct thread_info *);
113 extern void iwmmxt_task_copy(struct thread_info *, void *);
114 extern void iwmmxt_task_restore(struct thread_info *, void *);
115 extern void iwmmxt_task_release(struct thread_info *);
116 extern void iwmmxt_task_switch(struct thread_info *);
117 
118 extern void vfp_sync_hwstate(struct thread_info *);
119 extern void vfp_flush_hwstate(struct thread_info *);
120 
121 #endif
122 
123 /*
124  * We use bit 30 of the preempt_count to indicate that kernel
125  * preemption is occurring.  See <asm/hardirq.h>.
126  */
127 #define PREEMPT_ACTIVE	0x40000000
128 
129 /*
130  * thread information flags:
131  *  TIF_SYSCALL_TRACE	- syscall trace active
132  *  TIF_SIGPENDING	- signal pending
133  *  TIF_NEED_RESCHED	- rescheduling necessary
134  *  TIF_NOTIFY_RESUME	- callback before returning to user
135  *  TIF_USEDFPU		- FPU was used by this task this quantum (SMP)
136  *  TIF_POLLING_NRFLAG	- true if poll_idle() is polling TIF_NEED_RESCHED
137  */
138 #define TIF_SIGPENDING		0
139 #define TIF_NEED_RESCHED	1
140 #define TIF_NOTIFY_RESUME	2	/* callback before returning to user */
141 #define TIF_SYSCALL_TRACE	8
142 #define TIF_POLLING_NRFLAG	16
143 #define TIF_USING_IWMMXT	17
144 #define TIF_MEMDIE		18	/* is terminating due to OOM killer */
145 #define TIF_FREEZE		19
146 #define TIF_RESTORE_SIGMASK	20
147 #define TIF_SECCOMP		21
148 
149 #define _TIF_SIGPENDING		(1 << TIF_SIGPENDING)
150 #define _TIF_NEED_RESCHED	(1 << TIF_NEED_RESCHED)
151 #define _TIF_NOTIFY_RESUME	(1 << TIF_NOTIFY_RESUME)
152 #define _TIF_SYSCALL_TRACE	(1 << TIF_SYSCALL_TRACE)
153 #define _TIF_POLLING_NRFLAG	(1 << TIF_POLLING_NRFLAG)
154 #define _TIF_USING_IWMMXT	(1 << TIF_USING_IWMMXT)
155 #define _TIF_FREEZE		(1 << TIF_FREEZE)
156 #define _TIF_RESTORE_SIGMASK	(1 << TIF_RESTORE_SIGMASK)
157 #define _TIF_SECCOMP		(1 << TIF_SECCOMP)
158 
159 /*
160  * Change these and you break ASM code in entry-common.S
161  */
162 #define _TIF_WORK_MASK		0x000000ff
163 
164 #endif /* __KERNEL__ */
165 #endif /* __ASM_ARM_THREAD_INFO_H */
166