1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Thread support for the Hexagon architecture
4  *
5  * Copyright (c) 2010-2011, The Linux Foundation. All rights reserved.
6  */
7 
8 #ifndef _ASM_THREAD_INFO_H
9 #define _ASM_THREAD_INFO_H
10 
11 #ifdef __KERNEL__
12 
13 #ifndef __ASSEMBLY__
14 #include <asm/processor.h>
15 #include <asm/registers.h>
16 #include <asm/page.h>
17 #endif
18 
19 #define THREAD_SHIFT		12
20 #define THREAD_SIZE		(1<<THREAD_SHIFT)
21 #define THREAD_SIZE_ORDER	(THREAD_SHIFT - PAGE_SHIFT)
22 
23 #ifndef __ASSEMBLY__
24 
25 /*
26  * This is union'd with the "bottom" of the kernel stack.
27  * It keeps track of thread info which is handy for routines
28  * to access quickly.
29  */
30 
31 struct thread_info {
32 	struct task_struct	*task;		/* main task structure */
33 	unsigned long		flags;          /* low level flags */
34 	__u32                   cpu;            /* current cpu */
35 	int                     preempt_count;  /* 0=>preemptible,<0=>BUG */
36 	/*
37 	 * used for syscalls somehow;
38 	 * seems to have a function pointer and four arguments
39 	 */
40 	/* Points to the current pt_regs frame  */
41 	struct pt_regs		*regs;
42 	/*
43 	 * saved kernel sp at switch_to time;
44 	 * not sure if this is used (it's not in the VM model it seems;
45 	 * see thread_struct)
46 	 */
47 	unsigned long		sp;
48 };
49 
50 #else /* !__ASSEMBLY__ */
51 
52 #include <asm/asm-offsets.h>
53 
54 #endif  /* __ASSEMBLY__  */
55 
56 #ifndef __ASSEMBLY__
57 
58 #define INIT_THREAD_INFO(tsk)                   \
59 {                                               \
60 	.task           = &tsk,                 \
61 	.flags          = 0,                    \
62 	.cpu            = 0,                    \
63 	.preempt_count  = 1,                    \
64 	.sp = 0,				\
65 	.regs = NULL,			\
66 }
67 
68 /* Tacky preprocessor trickery */
69 #define	qqstr(s) qstr(s)
70 #define qstr(s) #s
71 #define QUOTED_THREADINFO_REG qqstr(THREADINFO_REG)
72 
73 register struct thread_info *__current_thread_info asm(QUOTED_THREADINFO_REG);
74 #define current_thread_info()  __current_thread_info
75 
76 #endif /* __ASSEMBLY__ */
77 
78 /*
79  * thread information flags
80  * - these are process state flags that various assembly files
81  *   may need to access
82  * - pending work-to-be-done flags are in LSW
83  * - other flags in MSW
84  */
85 
86 #define TIF_SYSCALL_TRACE       0       /* syscall trace active */
87 #define TIF_NOTIFY_RESUME       1       /* resumption notification requested */
88 #define TIF_SIGPENDING          2       /* signal pending */
89 #define TIF_NEED_RESCHED        3       /* rescheduling necessary */
90 #define TIF_SINGLESTEP          4       /* restore ss @ return to usr mode */
91 #define TIF_RESTORE_SIGMASK     6       /* restore sig mask in do_signal() */
92 #define TIF_NOTIFY_SIGNAL	7       /* signal notifications exist */
93 /* true if poll_idle() is polling TIF_NEED_RESCHED */
94 #define TIF_MEMDIE              17      /* OOM killer killed process */
95 
96 #define _TIF_SYSCALL_TRACE      (1 << TIF_SYSCALL_TRACE)
97 #define _TIF_NOTIFY_RESUME      (1 << TIF_NOTIFY_RESUME)
98 #define _TIF_SIGPENDING         (1 << TIF_SIGPENDING)
99 #define _TIF_NEED_RESCHED       (1 << TIF_NEED_RESCHED)
100 #define _TIF_SINGLESTEP         (1 << TIF_SINGLESTEP)
101 #define _TIF_NOTIFY_SIGNAL	(1 << TIF_NOTIFY_SIGNAL)
102 
103 /* work to do on interrupt/exception return - All but TIF_SYSCALL_TRACE */
104 #define _TIF_WORK_MASK          (0x0000FFFF & ~_TIF_SYSCALL_TRACE)
105 
106 /* work to do on any return to u-space */
107 #define _TIF_ALLWORK_MASK       0x0000FFFF
108 
109 #endif /* __KERNEL__ */
110 
111 #endif
112