summaryrefslogtreecommitdiffstats
path: root/include/asm-xtensa/thread_info.h
blob: af208d41fd821e842913a326f446315cba4bf57f (plain) (blame)
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
/*
 * include/asm-xtensa/thread_info.h
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (C) 2001 - 2005 Tensilica Inc.
 */

#ifndef _XTENSA_THREAD_INFO_H
#define _XTENSA_THREAD_INFO_H

#ifdef __KERNEL__

#ifndef __ASSEMBLY__
# include <asm/processor.h>
#endif

/*
 * low level task data that entry.S needs immediate access to
 * - this struct should fit entirely inside of one cache line
 * - this struct shares the supervisor stack pages
 * - if the contents of this structure are changed, the assembly constants
 *   must also be changed
 */

#ifndef __ASSEMBLY__

struct thread_info {
	struct task_struct	*task;		/* main task structure */
	struct exec_domain	*exec_domain;	/* execution domain */
	unsigned long		flags;		/* low level flags */
	unsigned long		status;		/* thread-synchronous flags */
	__u32			cpu;		/* current CPU */
	__s32			preempt_count;	/* 0 => preemptable,< 0 => BUG*/

	mm_segment_t		addr_limit;	/* thread address space */
	struct restart_block    restart_block;


};

#else /* !__ASSEMBLY__ */

/* offsets into the thread_info struct for assembly code access */
#define TI_TASK		 0x00000000
#define TI_EXEC_DOMAIN	 0x00000004
#define TI_FLAGS	 0x00000008
#define TI_STATUS	 0x0000000C
#define TI_CPU		 0x00000010
#define TI_PRE_COUNT	 0x00000014
#define TI_ADDR_LIMIT	 0x00000018
#define TI_RESTART_BLOCK 0x000001C

#endif

#define PREEMPT_ACTIVE		0x10000000

/*
 * macros/functions for gaining access to the thread information structure
 *
 * preempt_count needs to be 1 initially, until the scheduler is functional.
 */

#ifndef __ASSEMBLY__

#define INIT_THREAD_INFO(tsk)			\
{						\
	.task		= &tsk,			\
	.exec_domain	= &default_exec_domain,	\
	.flags		= 0,			\
	.cpu		= 0,			\
	.preempt_count	= 1,			\
	.addr_limit	= KERNEL_DS,		\
	.restart_block = {			\
		.fn = do_no_restart_syscall,	\
	},					\
}

#define init_thread_info	(init_thread_union.thread_info)
#define init_stack		(init_thread_union.stack)

/* how to get the thread information struct from C */
static inline struct thread_info *current_thread_info(void)
{
	struct thread_info *ti;
	 __asm__("extui %0,a1,0,13\n\t"
	         "xor %0, a1, %0" : "=&r" (ti) : );
	return ti;
}

/* thread information allocation */
#define alloc_thread_info(tsk) ((struct thread_info *) __get_free_pages(GFP_KERNEL,1))
#define free_thread_info(ti) free_pages((unsigned long) (ti), 1)
#define get_thread_info(ti) get_task_struct((ti)->task)
#define put_thread_info(ti) put_task_struct((ti)->task)

#else /* !__ASSEMBLY__ */

/* how to get the thread information struct from ASM */
#define GET_THREAD_INFO(reg,sp) \
	extui reg, sp, 0, 13; \
	xor   reg, sp, reg
#endif


/*
 * thread information flags
 * - these are process state flags that various assembly files may need to access
 * - pending work-to-be-done flags are in LSW
 * - other flags in MSW
 */
#define TIF_SYSCALL_TRACE	0	/* syscall trace active */
#define TIF_NOTIFY_RESUME	1	/* resumption notification requested */
#define TIF_SIGPENDING		2	/* signal pending */
#define TIF_NEED_RESCHED	3	/* rescheduling necessary */
#define TIF_SINGLESTEP		4	/* restore singlestep on return to user mode */
#define TIF_IRET		5	/* return with iret */
#define TIF_MEMDIE		6
#define TIF_POLLING_NRFLAG	16	/* true if poll_idle() is polling TIF_NEED_RESCHED */

#define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
#define _TIF_NOTIFY_RESUME	(1<<TIF_NOTIFY_RESUME)
#define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
#define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
#define _TIF_SINGLESTEP		(1<<TIF_SINGLESTEP)
#define _TIF_IRET		(1<<TIF_IRET)
#define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)

#define _TIF_WORK_MASK		0x0000FFFE	/* work to do on interrupt/exception return */
#define _TIF_ALLWORK_MASK	0x0000FFFF	/* work to do on any return to u-space */

/*
 * Thread-synchronous status.
 *
 * This is different from the flags in that nobody else
 * ever touches our thread-synchronous status, so we don't
 * have to worry about atomic accesses.
 */
#define TS_USEDFPU		0x0001	/* FPU was used by this task this quantum (SMP) */

#define THREAD_SIZE 8192	//(2*PAGE_SIZE)

#endif	/* __KERNEL__ */
#endif	/* _XTENSA_THREAD_INFO */