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 typedef struct {
26 	unsigned long seg;
27 } mm_segment_t;
28 
29 /*
30  * This is union'd with the "bottom" of the kernel stack.
31  * It keeps track of thread info which is handy for routines
32  * to access quickly.
33  */
34 
35 struct thread_info {
36 	struct task_struct	*task;		/* main task structure */
37 	unsigned long		flags;          /* low level flags */
38 	__u32                   cpu;            /* current cpu */
39 	int                     preempt_count;  /* 0=>preemptible,<0=>BUG */
40 	mm_segment_t            addr_limit;     /* segmentation sux */
41 	/*
42 	 * used for syscalls somehow;
43 	 * seems to have a function pointer and four arguments
44 	 */
45 	/* Points to the current pt_regs frame  */
46 	struct pt_regs		*regs;
47 	/*
48 	 * saved kernel sp at switch_to time;
49 	 * not sure if this is used (it's not in the VM model it seems;
50 	 * see thread_struct)
51 	 */
52 	unsigned long		sp;
53 };
54 
55 #else /* !__ASSEMBLY__ */
56 
57 #include <asm/asm-offsets.h>
58 
59 #endif  /* __ASSEMBLY__  */
60 
61 #ifndef __ASSEMBLY__
62 
63 #define INIT_THREAD_INFO(tsk)                   \
64 {                                               \
65 	.task           = &tsk,                 \
66 	.flags          = 0,                    \
67 	.cpu            = 0,                    \
68 	.preempt_count  = 1,                    \
69 	.addr_limit     = KERNEL_DS,            \
70 	.sp = 0,				\
71 	.regs = NULL,			\
72 }
73 
74 /* Tacky preprocessor trickery */
75 #define	qqstr(s) qstr(s)
76 #define qstr(s) #s
77 #define QUOTED_THREADINFO_REG qqstr(THREADINFO_REG)
78 
79 register struct thread_info *__current_thread_info asm(QUOTED_THREADINFO_REG);
80 #define current_thread_info()  __current_thread_info
81 
82 #endif /* __ASSEMBLY__ */
83 
84 /*
85  * thread information flags
86  * - these are process state flags that various assembly files
87  *   may need to access
88  * - pending work-to-be-done flags are in LSW
89  * - other flags in MSW
90  */
91 
92 #define TIF_SYSCALL_TRACE       0       /* syscall trace active */
93 #define TIF_NOTIFY_RESUME       1       /* resumption notification requested */
94 #define TIF_SIGPENDING          2       /* signal pending */
95 #define TIF_NEED_RESCHED        3       /* rescheduling necessary */
96 #define TIF_SINGLESTEP          4       /* restore ss @ return to usr mode */
97 #define TIF_RESTORE_SIGMASK     6       /* restore sig mask in do_signal() */
98 #define TIF_NOTIFY_SIGNAL	7       /* signal notifications exist */
99 /* true if poll_idle() is polling TIF_NEED_RESCHED */
100 #define TIF_MEMDIE              17      /* OOM killer killed process */
101 
102 #define _TIF_SYSCALL_TRACE      (1 << TIF_SYSCALL_TRACE)
103 #define _TIF_NOTIFY_RESUME      (1 << TIF_NOTIFY_RESUME)
104 #define _TIF_SIGPENDING         (1 << TIF_SIGPENDING)
105 #define _TIF_NEED_RESCHED       (1 << TIF_NEED_RESCHED)
106 #define _TIF_SINGLESTEP         (1 << TIF_SINGLESTEP)
107 #define _TIF_NOTIFY_SIGNAL	(1 << TIF_NOTIFY_SIGNAL)
108 
109 /* work to do on interrupt/exception return - All but TIF_SYSCALL_TRACE */
110 #define _TIF_WORK_MASK          (0x0000FFFF & ~_TIF_SYSCALL_TRACE)
111 
112 /* work to do on any return to u-space */
113 #define _TIF_ALLWORK_MASK       0x0000FFFF
114 
115 #endif /* __KERNEL__ */
116 
117 #endif
118