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 /*
43 * Size of kernel stack for each process. This must be a power of 2...
44 */
45 #define THREAD_SIZE_ORDER 1
46 #define THREAD_SIZE 8192 /* 2 pages */
47 #define STACK_WARN (THREAD_SIZE/8)
48
49 #ifndef __ASSEMBLY__
50
51 typedef unsigned long mm_segment_t;
52
53 /*
54 * low level task data.
55 * If you change this, change the TI_* offsets below to match.
56 */
57
58 struct thread_info {
59 struct task_struct *task; /* main task structure */
60 struct exec_domain *exec_domain; /* execution domain */
61 unsigned long flags; /* low level flags */
62 int cpu; /* cpu we're on */
63 int preempt_count; /* 0 => preemptable, <0 => BUG */
64 mm_segment_t addr_limit; /* address limit */
65 struct restart_block restart_block;
66 #ifndef CONFIG_SMP
67 struct l1_scratch_task_info l1_task_info;
68 #endif
69 };
70
71 /*
72 * macros/functions for gaining access to the thread information structure
73 */
74 #define INIT_THREAD_INFO(tsk) \
75 { \
76 .task = &tsk, \
77 .exec_domain = &default_exec_domain, \
78 .flags = 0, \
79 .cpu = 0, \
80 .preempt_count = 1, \
81 .restart_block = { \
82 .fn = do_no_restart_syscall, \
83 }, \
84 }
85 #define init_thread_info (init_thread_union.thread_info)
86 #define init_stack (init_thread_union.stack)
87
88 /* Given a task stack pointer, you can find its corresponding
89 * thread_info structure just by masking it to the THREAD_SIZE
90 * boundary (currently 8K as you can see above).
91 */
92 __attribute_const__
current_thread_info(void)93 static inline struct thread_info *current_thread_info(void)
94 {
95 struct thread_info *ti;
96 __asm__("%0 = sp;" : "=da"(ti) :
97 );
98 return (struct thread_info *)((long)ti & ~((long)THREAD_SIZE-1));
99 }
100
101 #endif /* __ASSEMBLY__ */
102
103 /*
104 * Offsets in thread_info structure, used in assembly code
105 */
106 #define TI_TASK 0
107 #define TI_EXECDOMAIN 4
108 #define TI_FLAGS 8
109 #define TI_CPU 12
110 #define TI_PREEMPT 16
111
112 #define PREEMPT_ACTIVE 0x4000000
113
114 /*
115 * thread information flag bit numbers
116 */
117 #define TIF_SYSCALL_TRACE 0 /* syscall trace active */
118 #define TIF_SIGPENDING 1 /* signal pending */
119 #define TIF_NEED_RESCHED 2 /* rescheduling necessary */
120 #define TIF_POLLING_NRFLAG 3 /* true if poll_idle() is polling
121 TIF_NEED_RESCHED */
122 #define TIF_MEMDIE 4
123 #define TIF_RESTORE_SIGMASK 5 /* restore signal mask in do_signal() */
124 #define TIF_FREEZE 6 /* is freezing for suspend */
125 #define TIF_IRQ_SYNC 7 /* sync pipeline stage */
126
127 /* as above, but as bit values */
128 #define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE)
129 #define _TIF_SIGPENDING (1<<TIF_SIGPENDING)
130 #define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED)
131 #define _TIF_POLLING_NRFLAG (1<<TIF_POLLING_NRFLAG)
132 #define _TIF_RESTORE_SIGMASK (1<<TIF_RESTORE_SIGMASK)
133 #define _TIF_FREEZE (1<<TIF_FREEZE)
134 #define _TIF_IRQ_SYNC (1<<TIF_IRQ_SYNC)
135
136 #define _TIF_WORK_MASK 0x0000FFFE /* work to do on interrupt/exception return */
137
138 #endif /* __KERNEL__ */
139
140 #endif /* _ASM_THREAD_INFO_H */
141