xref: /linux/arch/hexagon/include/asm/thread_info.h (revision f2ee442115c9b6219083c019939a9cc0c9abb2f8)
1 /*
2  * Thread support for the Hexagon architecture
3  *
4  * Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 and
8  * only version 2 as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
18  * 02110-1301, USA.
19  */
20 
21 #ifndef _ASM_THREAD_INFO_H
22 #define _ASM_THREAD_INFO_H
23 
24 #ifdef __KERNEL__
25 
26 #ifndef __ASSEMBLY__
27 #include <asm/processor.h>
28 #include <asm/registers.h>
29 #include <asm/page.h>
30 #endif
31 
32 #define THREAD_SHIFT		12
33 #define THREAD_SIZE		(1<<THREAD_SHIFT)
34 
35 #if THREAD_SHIFT >= PAGE_SHIFT
36 #define THREAD_SIZE_ORDER	(THREAD_SHIFT - PAGE_SHIFT)
37 #else  /*  don't use standard allocator  */
38 #define __HAVE_ARCH_THREAD_INFO_ALLOCATOR
39 extern struct thread_info *alloc_thread_info_node(struct task_struct *tsk, int node);
40 extern void free_thread_info(struct thread_info *ti);
41 #endif
42 
43 
44 #ifndef __ASSEMBLY__
45 
46 typedef struct {
47 	unsigned long seg;
48 } mm_segment_t;
49 
50 /*
51  * This is union'd with the "bottom" of the kernel stack.
52  * It keeps track of thread info which is handy for routines
53  * to access quickly.
54  */
55 
56 struct thread_info {
57 	struct task_struct	*task;		/* main task structure */
58 	struct exec_domain      *exec_domain;   /* execution domain */
59 	unsigned long		flags;          /* low level flags */
60 	__u32                   cpu;            /* current cpu */
61 	int                     preempt_count;  /* 0=>preemptible,<0=>BUG */
62 	mm_segment_t            addr_limit;     /* segmentation sux */
63 	/*
64 	 * used for syscalls somehow;
65 	 * seems to have a function pointer and four arguments
66 	 */
67 	struct restart_block    restart_block;
68 	/* Points to the current pt_regs frame  */
69 	struct pt_regs		*regs;
70 	/*
71 	 * saved kernel sp at switch_to time;
72 	 * not sure if this is used (it's not in the VM model it seems;
73 	 * see thread_struct)
74 	 */
75 	unsigned long		sp;
76 };
77 
78 #else /* !__ASSEMBLY__ */
79 
80 #include <asm/asm-offsets.h>
81 
82 #endif  /* __ASSEMBLY__  */
83 
84 /*  looks like "linux/hardirq.h" uses this.  */
85 
86 #define PREEMPT_ACTIVE		0x10000000
87 
88 #ifndef __ASSEMBLY__
89 
90 #define INIT_THREAD_INFO(tsk)                   \
91 {                                               \
92 	.task           = &tsk,                 \
93 	.exec_domain    = &default_exec_domain, \
94 	.flags          = 0,                    \
95 	.cpu            = 0,                    \
96 	.preempt_count  = 1,                    \
97 	.addr_limit     = KERNEL_DS,            \
98 	.restart_block = {                      \
99 		.fn = do_no_restart_syscall,    \
100 	},                                      \
101 	.sp = 0,				\
102 	.regs = NULL,			\
103 }
104 
105 #define init_thread_info        (init_thread_union.thread_info)
106 #define init_stack              (init_thread_union.stack)
107 
108 /* Tacky preprocessor trickery */
109 #define	qqstr(s) qstr(s)
110 #define qstr(s) #s
111 #define QUOTED_THREADINFO_REG qqstr(THREADINFO_REG)
112 
113 register struct thread_info *__current_thread_info asm(QUOTED_THREADINFO_REG);
114 #define current_thread_info()  __current_thread_info
115 
116 #endif /* __ASSEMBLY__ */
117 
118 /*
119  * thread information flags
120  * - these are process state flags that various assembly files
121  *   may need to access
122  * - pending work-to-be-done flags are in LSW
123  * - other flags in MSW
124  */
125 
126 #define TIF_SYSCALL_TRACE       0       /* syscall trace active */
127 #define TIF_NOTIFY_RESUME       1       /* resumption notification requested */
128 #define TIF_SIGPENDING          2       /* signal pending */
129 #define TIF_NEED_RESCHED        3       /* rescheduling necessary */
130 #define TIF_SINGLESTEP          4       /* restore ss @ return to usr mode */
131 #define TIF_IRET                5       /* return with iret */
132 #define TIF_RESTORE_SIGMASK     6       /* restore sig mask in do_signal() */
133 /* true if poll_idle() is polling TIF_NEED_RESCHED */
134 #define TIF_POLLING_NRFLAG      16
135 #define TIF_MEMDIE              17      /* OOM killer killed process */
136 
137 #define _TIF_SYSCALL_TRACE      (1 << TIF_SYSCALL_TRACE)
138 #define _TIF_NOTIFY_RESUME      (1 << TIF_NOTIFY_RESUME)
139 #define _TIF_SIGPENDING         (1 << TIF_SIGPENDING)
140 #define _TIF_NEED_RESCHED       (1 << TIF_NEED_RESCHED)
141 #define _TIF_SINGLESTEP         (1 << TIF_SINGLESTEP)
142 #define _TIF_IRET               (1 << TIF_IRET)
143 #define _TIF_RESTORE_SIGMASK    (1 << TIF_RESTORE_SIGMASK)
144 #define _TIF_POLLING_NRFLAG     (1 << TIF_POLLING_NRFLAG)
145 
146 /* work to do on interrupt/exception return - All but TIF_SYSCALL_TRACE */
147 #define _TIF_WORK_MASK          (0x0000FFFF & ~_TIF_SYSCALL_TRACE)
148 
149 /* work to do on any return to u-space */
150 #define _TIF_ALLWORK_MASK       0x0000FFFF
151 
152 #endif /* __KERNEL__ */
153 
154 #endif
155