1/*
2 * OpenRISC Linux
3 *
4 * Linux architectural port borrowing liberally from similar works of
5 * others.  All original copyrights apply as per the original source
6 * declaration.
7 *
8 * OpenRISC implementation:
9 * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
10 * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
11 * et al.
12 *
13 * This program is free software; you can redistribute it and/or modify
14 * it under the terms of the GNU General Public License as published by
15 * the Free Software Foundation; either version 2 of the License, or
16 * (at your option) any later version.
17 */
18
19#ifndef _ASM_THREAD_INFO_H
20#define _ASM_THREAD_INFO_H
21
22#ifdef __KERNEL__
23
24#ifndef __ASSEMBLY__
25#include <asm/types.h>
26#include <asm/processor.h>
27#endif
28
29
30/* THREAD_SIZE is the size of the task_struct/kernel_stack combo.
31 * normally, the stack is found by doing something like p + THREAD_SIZE
32 * in or32, a page is 8192 bytes, which seems like a sane size
33 */
34
35#define THREAD_SIZE_ORDER 0
36#define THREAD_SIZE       (PAGE_SIZE << THREAD_SIZE_ORDER)
37
38/*
39 * low level task data that entry.S needs immediate access to
40 * - this struct should fit entirely inside of one cache line
41 * - this struct shares the supervisor stack pages
42 * - if the contents of this structure are changed, the assembly constants
43 *   must also be changed
44 */
45#ifndef __ASSEMBLY__
46
47typedef unsigned long mm_segment_t;
48
49struct thread_info {
50	struct task_struct	*task;		/* main task structure */
51	unsigned long		flags;		/* low level flags */
52	__u32			cpu;		/* current CPU */
53	__s32			preempt_count; /* 0 => preemptable, <0 => BUG */
54
55	mm_segment_t		addr_limit; /* thread address space:
56					       0-0x7FFFFFFF for user-thead
57					       0-0xFFFFFFFF for kernel-thread
58					     */
59	__u8			supervisor_stack[0];
60
61	/* saved context data */
62	unsigned long           ksp;
63};
64#endif
65
66/*
67 * macros/functions for gaining access to the thread information structure
68 *
69 * preempt_count needs to be 1 initially, until the scheduler is functional.
70 */
71#ifndef __ASSEMBLY__
72#define INIT_THREAD_INFO(tsk)				\
73{							\
74	.task		= &tsk,				\
75	.flags		= 0,				\
76	.cpu		= 0,				\
77	.preempt_count	= 1,				\
78	.addr_limit	= KERNEL_DS,			\
79	.ksp            = 0,                            \
80}
81
82#define init_thread_info	(init_thread_union.thread_info)
83
84/* how to get the thread information struct from C */
85register struct thread_info *current_thread_info_reg asm("r10");
86#define current_thread_info()   (current_thread_info_reg)
87
88#define get_thread_info(ti) get_task_struct((ti)->task)
89#define put_thread_info(ti) put_task_struct((ti)->task)
90
91#endif /* !__ASSEMBLY__ */
92
93/*
94 * thread information flags
95 *   these are process state flags that various assembly files may need to
96 *   access
97 *   - pending work-to-be-done flags are in LSW
98 *   - other flags in MSW
99 */
100#define TIF_SYSCALL_TRACE	0	/* syscall trace active */
101#define TIF_NOTIFY_RESUME	1	/* resumption notification requested */
102#define TIF_SIGPENDING		2	/* signal pending */
103#define TIF_NEED_RESCHED	3	/* rescheduling necessary */
104#define TIF_SINGLESTEP		4	/* restore singlestep on return to user
105					 * mode
106					 */
107#define TIF_SYSCALL_TRACEPOINT  8       /* for ftrace syscall instrumentation */
108#define TIF_RESTORE_SIGMASK     9
109#define TIF_POLLING_NRFLAG	16	/* true if poll_idle() is polling						 * TIF_NEED_RESCHED
110					 */
111#define TIF_MEMDIE              17
112
113#define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
114#define _TIF_NOTIFY_RESUME	(1<<TIF_NOTIFY_RESUME)
115#define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
116#define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
117#define _TIF_SINGLESTEP		(1<<TIF_SINGLESTEP)
118#define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
119
120
121/* Work to do when returning from interrupt/exception */
122/* For OpenRISC, this is anything in the LSW other than syscall trace */
123#define _TIF_WORK_MASK (0xff & ~(_TIF_SYSCALL_TRACE|_TIF_SINGLESTEP))
124
125#endif /* __KERNEL__ */
126
127#endif /* _ASM_THREAD_INFO_H */
128