arch/xtensa/include/asm/thread_info.h

   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 #include <asm/kmem_layout.h>
  15
  16 #define CURRENT_SHIFT KERNEL_STACK_SHIFT
  17
  18 #ifndef __ASSEMBLY__
  19 # include <asm/processor.h>
  20 #endif
  21
  22 /*
  23  * low level task data that entry.S needs immediate access to
  24  * - this struct should fit entirely inside of one cache line
  25  * - this struct shares the supervisor stack pages
  26  * - if the contents of this structure are changed, the assembly constants
  27  *   must also be changed
  28  */
  29
  30 #ifndef __ASSEMBLY__
  31
  32 #if XTENSA_HAVE_COPROCESSORS
  33
  34 typedef struct xtregs_coprocessor {
  35         xtregs_cp0_t cp0;
  36         xtregs_cp1_t cp1;
  37         xtregs_cp2_t cp2;
  38         xtregs_cp3_t cp3;
  39         xtregs_cp4_t cp4;
  40         xtregs_cp5_t cp5;
  41         xtregs_cp6_t cp6;
  42         xtregs_cp7_t cp7;
  43 } xtregs_coprocessor_t;
  44
  45 #endif
  46
  47 struct thread_info {
  48         struct task_struct      *task;          /* main task structure */
  49         unsigned long           flags;          /* low level flags */
  50         unsigned long           status;         /* thread-synchronous flags */
  51         __u32                   cpu;            /* current CPU */
  52         __s32                   preempt_count;  /* 0 => preemptable,< 0 => BUG*/
  53
  54         mm_segment_t            addr_limit;     /* thread address space */
  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 #endif
  66
  67 /*
  68  * macros/functions for gaining access to the thread information structure
  69  */
  70
  71 #ifndef __ASSEMBLY__
  72
  73 #define INIT_THREAD_INFO(tsk)                   \
  74 {                                               \
  75         .task           = &tsk,                 \
  76         .flags          = 0,                    \
  77         .cpu            = 0,                    \
  78         .preempt_count  = INIT_PREEMPT_COUNT,   \
  79         .addr_limit     = KERNEL_DS,            \
  80 }
  81
  82 /* how to get the thread information struct from C */
  83 static inline struct thread_info *current_thread_info(void)
  84 {
  85         struct thread_info *ti;
  86          __asm__("extui %0, a1, 0, "__stringify(CURRENT_SHIFT)"\n\t"
  87                  "xor %0, a1, %0" : "=&r" (ti) : );
  88         return ti;
  89 }
  90
  91 #else /* !__ASSEMBLY__ */
  92
  93 /* how to get the thread information struct from ASM */
  94 #define GET_THREAD_INFO(reg,sp) \
  95         extui reg, sp, 0, CURRENT_SHIFT; \
  96         xor   reg, sp, reg
  97 #endif
  98
  99
 100 /*
 101  * thread information flags
 102  * - these are process state flags that various assembly files may need to access
 103  * - pending work-to-be-done flags are in LSW
 104  * - other flags in MSW
 105  */
 106 #define TIF_SYSCALL_TRACE       0       /* syscall trace active */
 107 #define TIF_SIGPENDING          1       /* signal pending */
 108 #define TIF_NEED_RESCHED        2       /* rescheduling necessary */
 109 #define TIF_SINGLESTEP          3       /* restore singlestep on return to user mode */
 110 #define TIF_MEMDIE              5       /* is terminating due to OOM killer */
 111 #define TIF_RESTORE_SIGMASK     6       /* restore signal mask in do_signal() */
 112 #define TIF_NOTIFY_RESUME       7       /* callback before returning to user */
 113 #define TIF_DB_DISABLED         8       /* debug trap disabled for syscall */
 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 KERNEL_STACK_SIZE
 133 #define THREAD_SIZE_ORDER (KERNEL_STACK_SHIFT - PAGE_SHIFT)
 134
 135 #endif  /* _XTENSA_THREAD_INFO */