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 	struct exec_domain	*exec_domain;	/* execution domain */
48 	unsigned long		flags;		/* low level flags */
49 	unsigned long		status;		/* thread-synchronous flags */
50 	__u32			cpu;		/* current CPU */
51 	__s32			preempt_count;	/* 0 => preemptable,< 0 => BUG*/
52 
53 	mm_segment_t		addr_limit;	/* thread address space */
54 	struct restart_block    restart_block;
55 
56 	unsigned long		cpenable;
57 
58 	/* Allocate storage for extra user states and coprocessor states. */
59 #if XTENSA_HAVE_COPROCESSORS
60 	xtregs_coprocessor_t	xtregs_cp;
61 #endif
62 	xtregs_user_t		xtregs_user;
63 };
64 
65 #else /* !__ASSEMBLY__ */
66 
67 /* offsets into the thread_info struct for assembly code access */
68 #define TI_TASK		 0x00000000
69 #define TI_EXEC_DOMAIN	 0x00000004
70 #define TI_FLAGS	 0x00000008
71 #define TI_STATUS	 0x0000000C
72 #define TI_CPU		 0x00000010
73 #define TI_PRE_COUNT	 0x00000014
74 #define TI_ADDR_LIMIT	 0x00000018
75 #define TI_RESTART_BLOCK 0x000001C
76 
77 #endif
78 
79 #define PREEMPT_ACTIVE		0x10000000
80 
81 /*
82  * macros/functions for gaining access to the thread information structure
83  *
84  * preempt_count needs to be 1 initially, until the scheduler is functional.
85  */
86 
87 #ifndef __ASSEMBLY__
88 
89 #define INIT_THREAD_INFO(tsk)			\
90 {						\
91 	.task		= &tsk,			\
92 	.exec_domain	= &default_exec_domain,	\
93 	.flags		= 0,			\
94 	.cpu		= 0,			\
95 	.preempt_count	= 1,			\
96 	.addr_limit	= KERNEL_DS,		\
97 	.restart_block = {			\
98 		.fn = do_no_restart_syscall,	\
99 	},					\
100 }
101 
102 #define init_thread_info	(init_thread_union.thread_info)
103 #define init_stack		(init_thread_union.stack)
104 
105 /* how to get the thread information struct from C */
106 static inline struct thread_info *current_thread_info(void)
107 {
108 	struct thread_info *ti;
109 	 __asm__("extui %0,a1,0,13\n\t"
110 	         "xor %0, a1, %0" : "=&r" (ti) : );
111 	return ti;
112 }
113 
114 #else /* !__ASSEMBLY__ */
115 
116 /* how to get the thread information struct from ASM */
117 #define GET_THREAD_INFO(reg,sp) \
118 	extui reg, sp, 0, 13; \
119 	xor   reg, sp, reg
120 #endif
121 
122 
123 /*
124  * thread information flags
125  * - these are process state flags that various assembly files may need to access
126  * - pending work-to-be-done flags are in LSW
127  * - other flags in MSW
128  */
129 #define TIF_SYSCALL_TRACE	0	/* syscall trace active */
130 #define TIF_SIGPENDING		1	/* signal pending */
131 #define TIF_NEED_RESCHED	2	/* rescheduling necessary */
132 #define TIF_SINGLESTEP		3	/* restore singlestep on return to user mode */
133 #define TIF_IRET		4	/* return with iret */
134 #define TIF_MEMDIE		5
135 #define TIF_RESTORE_SIGMASK	6	/* restore signal mask in do_signal() */
136 #define TIF_POLLING_NRFLAG	16	/* true if poll_idle() is polling TIF_NEED_RESCHED */
137 #define TIF_FREEZE		17	/* is freezing for suspend */
138 
139 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
140 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
141 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
142 #define _TIF_SINGLESTEP		(1<<TIF_SINGLESTEP)
143 #define _TIF_IRET		(1<<TIF_IRET)
144 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
145 #define _TIF_RESTORE_SIGMASK	(1<<TIF_RESTORE_SIGMASK)
146 #define _TIF_FREEZE		(1<<TIF_FREEZE)
147 
148 #define _TIF_WORK_MASK		0x0000FFFE	/* work to do on interrupt/exception return */
149 #define _TIF_ALLWORK_MASK	0x0000FFFF	/* work to do on any return to u-space */
150 
151 /*
152  * Thread-synchronous status.
153  *
154  * This is different from the flags in that nobody else
155  * ever touches our thread-synchronous status, so we don't
156  * have to worry about atomic accesses.
157  */
158 #define TS_USEDFPU		0x0001	/* FPU was used by this task this quantum (SMP) */
159 
160 #define THREAD_SIZE 8192	//(2*PAGE_SIZE)
161 #define THREAD_SIZE_ORDER 1
162 
163 #endif	/* __KERNEL__ */
164 #endif	/* _XTENSA_THREAD_INFO */
165