1 /*
2  * NiosII low-level thread information
3  *
4  * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
5  * Copyright (C) 2004 Microtronix Datacom Ltd.
6  *
7  * Based on asm/thread_info_no.h from m68k which is:
8  *
9  * Copyright (C) 2002 David Howells <dhowells@redhat.com>
10  *
11  * This file is subject to the terms and conditions of the GNU General Public
12  * License.  See the file "COPYING" in the main directory of this archive
13  * for more details.
14  */
15 
16 #ifndef _ASM_NIOS2_THREAD_INFO_H
17 #define _ASM_NIOS2_THREAD_INFO_H
18 
19 #ifdef __KERNEL__
20 
21 /*
22  * Size of the kernel stack for each process.
23  */
24 #define THREAD_SIZE_ORDER	1
25 #define THREAD_SIZE		8192 /* 2 * PAGE_SIZE */
26 
27 #ifndef __ASSEMBLY__
28 
29 /*
30  * low level task data that entry.S needs immediate access to
31  * - this struct should fit entirely inside of one cache line
32  * - this struct shares the supervisor stack pages
33  * - if the contents of this structure are changed, the assembly constants
34  *   must also be changed
35  */
36 struct thread_info {
37 	struct task_struct	*task;		/* main task structure */
38 	unsigned long		flags;		/* low level flags */
39 	__u32			cpu;		/* current CPU */
40 	int			preempt_count;	/* 0 => preemptable,<0 => BUG */
41 	struct pt_regs		*regs;
42 };
43 
44 /*
45  * macros/functions for gaining access to the thread information structure
46  *
47  * preempt_count needs to be 1 initially, until the scheduler is functional.
48  */
49 #define INIT_THREAD_INFO(tsk)			\
50 {						\
51 	.task		= &tsk,			\
52 	.flags		= 0,			\
53 	.cpu		= 0,			\
54 	.preempt_count	= INIT_PREEMPT_COUNT,	\
55 }
56 
57 /* how to get the thread information struct from C */
current_thread_info(void)58 static inline struct thread_info *current_thread_info(void)
59 {
60 	register unsigned long sp asm("sp");
61 
62 	return (struct thread_info *)(sp & ~(THREAD_SIZE - 1));
63 }
64 #endif /* !__ASSEMBLY__ */
65 
66 /*
67  * thread information flags
68  * - these are process state flags that various assembly files may need to
69  *   access
70  * - pending work-to-be-done flags are in LSW
71  * - other flags in MSW
72  */
73 #define TIF_SYSCALL_TRACE	0	/* syscall trace active */
74 #define TIF_NOTIFY_RESUME	1	/* resumption notification requested */
75 #define TIF_SIGPENDING		2	/* signal pending */
76 #define TIF_NEED_RESCHED	3	/* rescheduling necessary */
77 #define TIF_MEMDIE		4	/* is terminating due to OOM killer */
78 #define TIF_SECCOMP		5	/* secure computing */
79 #define TIF_SYSCALL_AUDIT	6	/* syscall auditing active */
80 #define TIF_NOTIFY_SIGNAL	7	/* signal notifications exist */
81 #define TIF_RESTORE_SIGMASK	9	/* restore signal mask in do_signal() */
82 
83 #define TIF_POLLING_NRFLAG	16	/* true if poll_idle() is polling
84 					   TIF_NEED_RESCHED */
85 
86 #define _TIF_SYSCALL_TRACE	(1 << TIF_SYSCALL_TRACE)
87 #define _TIF_NOTIFY_RESUME	(1 << TIF_NOTIFY_RESUME)
88 #define _TIF_SIGPENDING		(1 << TIF_SIGPENDING)
89 #define _TIF_NEED_RESCHED	(1 << TIF_NEED_RESCHED)
90 #define _TIF_SECCOMP		(1 << TIF_SECCOMP)
91 #define _TIF_SYSCALL_AUDIT	(1 << TIF_SYSCALL_AUDIT)
92 #define _TIF_NOTIFY_SIGNAL	(1 << TIF_NOTIFY_SIGNAL)
93 #define _TIF_RESTORE_SIGMASK	(1 << TIF_RESTORE_SIGMASK)
94 #define _TIF_POLLING_NRFLAG	(1 << TIF_POLLING_NRFLAG)
95 
96 /* work to do on interrupt/exception return */
97 #define _TIF_WORK_MASK		0x0000FFFE
98 
99 /* work to do on any return to u-space */
100 # define _TIF_ALLWORK_MASK	0x0000FFFF
101 
102 #endif /* __KERNEL__ */
103 
104 #endif /* _ASM_NIOS2_THREAD_INFO_H */
105