1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * OpenRISC Linux
4  *
5  * Linux architectural port borrowing liberally from similar works of
6  * others.  All original copyrights apply as per the original source
7  * declaration.
8  *
9  * OpenRISC implementation:
10  * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
11  * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
12  * et al.
13  */
14 
15 #ifndef _ASM_THREAD_INFO_H
16 #define _ASM_THREAD_INFO_H
17 
18 #ifdef __KERNEL__
19 
20 #ifndef __ASSEMBLY__
21 #include <asm/types.h>
22 #include <asm/processor.h>
23 #endif
24 
25 
26 /* THREAD_SIZE is the size of the task_struct/kernel_stack combo.
27  * normally, the stack is found by doing something like p + THREAD_SIZE
28  * in or32, a page is 8192 bytes, which seems like a sane size
29  */
30 
31 #define THREAD_SIZE_ORDER 0
32 #define THREAD_SIZE       (PAGE_SIZE << THREAD_SIZE_ORDER)
33 
34 /*
35  * low level task data that entry.S needs immediate access to
36  * - this struct should fit entirely inside of one cache line
37  * - this struct shares the supervisor stack pages
38  * - if the contents of this structure are changed, the assembly constants
39  *   must also be changed
40  */
41 #ifndef __ASSEMBLY__
42 
43 typedef unsigned long mm_segment_t;
44 
45 struct thread_info {
46 	struct task_struct	*task;		/* main task structure */
47 	unsigned long		flags;		/* low level flags */
48 	__u32			cpu;		/* current CPU */
49 	__s32			preempt_count; /* 0 => preemptable, <0 => BUG */
50 
51 	mm_segment_t		addr_limit; /* thread address space:
52 					       0-0x7FFFFFFF for user-thead
53 					       0-0xFFFFFFFF for kernel-thread
54 					     */
55 	__u8			supervisor_stack[0];
56 
57 	/* saved context data */
58 	unsigned long           ksp;
59 };
60 #endif
61 
62 /*
63  * macros/functions for gaining access to the thread information structure
64  *
65  * preempt_count needs to be 1 initially, until the scheduler is functional.
66  */
67 #ifndef __ASSEMBLY__
68 #define INIT_THREAD_INFO(tsk)				\
69 {							\
70 	.task		= &tsk,				\
71 	.flags		= 0,				\
72 	.cpu		= 0,				\
73 	.preempt_count	= INIT_PREEMPT_COUNT,		\
74 	.addr_limit	= KERNEL_DS,			\
75 	.ksp            = 0,                            \
76 }
77 
78 /* how to get the thread information struct from C */
79 register struct thread_info *current_thread_info_reg asm("r10");
80 #define current_thread_info()   (current_thread_info_reg)
81 
82 #define get_thread_info(ti) get_task_struct((ti)->task)
83 #define put_thread_info(ti) put_task_struct((ti)->task)
84 
85 #endif /* !__ASSEMBLY__ */
86 
87 /*
88  * thread information flags
89  *   these are process state flags that various assembly files may need to
90  *   access
91  *   - pending work-to-be-done flags are in LSW
92  *   - other flags in MSW
93  */
94 #define TIF_SYSCALL_TRACE	0	/* syscall trace active */
95 #define TIF_NOTIFY_RESUME	1	/* resumption notification requested */
96 #define TIF_SIGPENDING		2	/* signal pending */
97 #define TIF_NEED_RESCHED	3	/* rescheduling necessary */
98 #define TIF_SINGLESTEP		4	/* restore singlestep on return to user
99 					 * mode
100 					 */
101 #define TIF_SYSCALL_TRACEPOINT  8       /* for ftrace syscall instrumentation */
102 #define TIF_RESTORE_SIGMASK     9
103 #define TIF_POLLING_NRFLAG	16	/* true if poll_idle() is polling						 * TIF_NEED_RESCHED
104 					 */
105 #define TIF_MEMDIE              17
106 
107 #define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
108 #define _TIF_NOTIFY_RESUME	(1<<TIF_NOTIFY_RESUME)
109 #define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
110 #define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
111 #define _TIF_SINGLESTEP		(1<<TIF_SINGLESTEP)
112 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
113 
114 
115 /* Work to do when returning from interrupt/exception */
116 /* For OpenRISC, this is anything in the LSW other than syscall trace */
117 #define _TIF_WORK_MASK (0xff & ~(_TIF_SYSCALL_TRACE|_TIF_SINGLESTEP))
118 
119 #endif /* __KERNEL__ */
120 
121 #endif /* _ASM_THREAD_INFO_H */
122