1 /*
2  * include/asm-xtensa/thread_info.h
3  *
4  * This file is subject to the terms and conditions of the GNU General Public
5  * License.  See the file "COPYING" in the main directory of this archive
6  * for more details.
7  *
8  * Copyright (C) 2001 - 2005 Tensilica Inc.
9  */
10 
11 #ifndef _XTENSA_THREAD_INFO_H
12 #define _XTENSA_THREAD_INFO_H
13 
14 #ifdef __KERNEL__
15 
16 #ifndef __ASSEMBLY__
17 # include <asm/processor.h>
18 #endif
19 
20 /*
21  * low level task data that entry.S needs immediate access to
22  * - this struct should fit entirely inside of one cache line
23  * - this struct shares the supervisor stack pages
24  * - if the contents of this structure are changed, the assembly constants
25  *   must also be changed
26  */
27 
28 #ifndef __ASSEMBLY__
29 
30 #if XTENSA_HAVE_COPROCESSORS
31 
32 typedef struct xtregs_coprocessor {
33 	xtregs_cp0_t cp0;
34 	xtregs_cp1_t cp1;
35 	xtregs_cp2_t cp2;
36 	xtregs_cp3_t cp3;
37 	xtregs_cp4_t cp4;
38 	xtregs_cp5_t cp5;
39 	xtregs_cp6_t cp6;
40 	xtregs_cp7_t cp7;
41 } xtregs_coprocessor_t;
42 
43 #endif
44 
45 struct thread_info {
46 	struct task_struct	*task;		/* main task structure */
47 	unsigned long		flags;		/* low level flags */
48 	unsigned long		status;		/* thread-synchronous flags */
49 	__u32			cpu;		/* current CPU */
50 	__s32			preempt_count;	/* 0 => preemptable,< 0 => BUG*/
51 
52 	mm_segment_t		addr_limit;	/* thread address space */
53 
54 	unsigned long		cpenable;
55 
56 	/* Allocate storage for extra user states and coprocessor states. */
57 #if XTENSA_HAVE_COPROCESSORS
58 	xtregs_coprocessor_t	xtregs_cp;
59 #endif
60 	xtregs_user_t		xtregs_user;
61 };
62 
63 #endif
64 
65 /*
66  * macros/functions for gaining access to the thread information structure
67  */
68 
69 #ifndef __ASSEMBLY__
70 
71 #define INIT_THREAD_INFO(tsk)			\
72 {						\
73 	.task		= &tsk,			\
74 	.flags		= 0,			\
75 	.cpu		= 0,			\
76 	.preempt_count	= INIT_PREEMPT_COUNT,	\
77 	.addr_limit	= KERNEL_DS,		\
78 }
79 
80 #define init_thread_info	(init_thread_union.thread_info)
81 #define init_stack		(init_thread_union.stack)
82 
83 /* how to get the thread information struct from C */
84 static inline struct thread_info *current_thread_info(void)
85 {
86 	struct thread_info *ti;
87 	 __asm__("extui %0,a1,0,13\n\t"
88 	         "xor %0, a1, %0" : "=&r" (ti) : );
89 	return ti;
90 }
91 
92 #else /* !__ASSEMBLY__ */
93 
94 /* how to get the thread information struct from ASM */
95 #define GET_THREAD_INFO(reg,sp) \
96 	extui reg, sp, 0, 13; \
97 	xor   reg, sp, reg
98 #endif
99 
100 
101 /*
102  * thread information flags
103  * - these are process state flags that various assembly files may need to access
104  * - pending work-to-be-done flags are in LSW
105  * - other flags in MSW
106  */
107 #define TIF_SYSCALL_TRACE	0	/* syscall trace active */
108 #define TIF_SIGPENDING		1	/* signal pending */
109 #define TIF_NEED_RESCHED	2	/* rescheduling necessary */
110 #define TIF_SINGLESTEP		3	/* restore singlestep on return to user mode */
111 #define TIF_MEMDIE		5	/* is terminating due to OOM killer */
112 #define TIF_RESTORE_SIGMASK	6	/* restore signal mask in do_signal() */
113 #define TIF_NOTIFY_RESUME	7	/* callback before returning to user */
114 
115 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
116 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
117 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
118 #define _TIF_SINGLESTEP		(1<<TIF_SINGLESTEP)
119 
120 #define _TIF_WORK_MASK		0x0000FFFE	/* work to do on interrupt/exception return */
121 #define _TIF_ALLWORK_MASK	0x0000FFFF	/* work to do on any return to u-space */
122 
123 /*
124  * Thread-synchronous status.
125  *
126  * This is different from the flags in that nobody else
127  * ever touches our thread-synchronous status, so we don't
128  * have to worry about atomic accesses.
129  */
130 #define TS_USEDFPU		0x0001	/* FPU was used by this task this quantum (SMP) */
131 
132 #define THREAD_SIZE 8192	//(2*PAGE_SIZE)
133 #define THREAD_SIZE_ORDER 1
134 
135 #endif	/* __KERNEL__ */
136 #endif	/* _XTENSA_THREAD_INFO */
137