1/*
2 * File:         include/asm-blackfin/thread_info.h
3 * Based on:     include/asm-m68knommu/thread_info.h
4 * Author:       LG Soft India
5 *               Copyright (C) 2004-2005 Analog Devices Inc.
6 * Created:      Tue Sep 21 2004
7 * Description:  Blackfin low-level thread information
8 * Modified:
9 * Bugs:         Enter bugs at http://blackfin.uclinux.org/
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2, or (at your option)
14 * any later version.
15 *
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19 * GNU General Public License for more details.
20 *
21 * You should have received a copy of the GNU General Public License
22 * along with this program; see the file COPYING.
23 * If not, write to the Free Software Foundation,
24 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
25 */
26
27#ifndef _ASM_THREAD_INFO_H
28#define _ASM_THREAD_INFO_H
29
30#include <asm/page.h>
31#include <asm/entry.h>
32#include <asm/l1layout.h>
33#include <linux/compiler.h>
34
35#ifdef __KERNEL__
36
37/* Thread Align Mask to reach to the top of the stack
38 * for any process
39 */
40#define ALIGN_PAGE_MASK         0xffffe000
41
42#ifndef __ASSEMBLY__
43
44typedef unsigned long mm_segment_t;
45
46/*
47 * low level task data.
48 * If you change this, change the TI_* offsets below to match.
49 */
50
51struct thread_info {
52	struct task_struct *task;	/* main task structure */
53	struct exec_domain *exec_domain;	/* execution domain */
54	unsigned long flags;	/* low level flags */
55	int cpu;		/* cpu we're on */
56	int preempt_count;	/* 0 => preemptable, <0 => BUG */
57	mm_segment_t addr_limit;	/* address limit */
58	struct restart_block restart_block;
59	struct l1_scratch_task_info l1_task_info;
60};
61
62/*
63 * macros/functions for gaining access to the thread information structure
64 */
65#define INIT_THREAD_INFO(tsk)			\
66{						\
67	.task		= &tsk,			\
68	.exec_domain	= &default_exec_domain,	\
69	.flags		= 0,			\
70	.cpu		= 0,			\
71	.preempt_count  = 1,                    \
72	.restart_block	= {			\
73		.fn = do_no_restart_syscall,	\
74	},					\
75}
76#define init_thread_info	(init_thread_union.thread_info)
77#define init_stack		(init_thread_union.stack)
78
79/*
80 * Size of kernel stack for each process. This must be a power of 2...
81 */
82#define THREAD_SIZE		8192	/* 2 pages */
83
84/* How to get the thread information struct from C */
85
86static inline struct thread_info *current_thread_info(void)
87    __attribute__ ((__const__));
88
89/* Given a task stack pointer, you can find it's task structure
90 * just by masking it to the 8K boundary.
91 */
92static inline struct thread_info *current_thread_info(void)
93{
94	struct thread_info *ti;
95      __asm__("%0 = sp;": "=&d"(ti):
96	);
97	return (struct thread_info *)((long)ti & ~8191UL);
98}
99
100/* thread information allocation */
101#define alloc_thread_info(tsk) ((struct thread_info *) \
102				__get_free_pages(GFP_KERNEL, 1))
103#define free_thread_info(ti)	free_pages((unsigned long) (ti), 1)
104#endif				/* __ASSEMBLY__ */
105
106/*
107 * Offsets in thread_info structure, used in assembly code
108 */
109#define TI_TASK		0
110#define TI_EXECDOMAIN	4
111#define TI_FLAGS	8
112#define TI_CPU		12
113#define TI_PREEMPT	16
114
115#define	PREEMPT_ACTIVE	0x4000000
116
117/*
118 * thread information flag bit numbers
119 */
120#define TIF_SYSCALL_TRACE	0	/* syscall trace active */
121#define TIF_NOTIFY_RESUME	1	/* resumption notification requested */
122#define TIF_SIGPENDING		2	/* signal pending */
123#define TIF_NEED_RESCHED	3	/* rescheduling necessary */
124#define TIF_POLLING_NRFLAG	4	/* true if poll_idle() is polling
125					   TIF_NEED_RESCHED */
126#define TIF_MEMDIE              5
127#define TIF_RESTORE_SIGMASK	6	/* restore signal mask in do_signal() */
128#define TIF_FREEZE              7       /* is freezing for suspend */
129
130/* as above, but as bit values */
131#define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
132#define _TIF_NOTIFY_RESUME	(1<<TIF_NOTIFY_RESUME)
133#define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
134#define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
135#define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
136#define _TIF_RESTORE_SIGMASK	(1<<TIF_RESTORE_SIGMASK)
137#define _TIF_FREEZE             (1<<TIF_FREEZE)
138
139#define _TIF_WORK_MASK		0x0000FFFE	/* work to do on interrupt/exception return */
140
141#endif				/* __KERNEL__ */
142
143#endif				/* _ASM_THREAD_INFO_H */
144