LXR linux/arch/c6x/include/asm/thread

   1/*
   2 *  Port on Texas Instruments TMS320C6x architecture
   3 *
   4 *  Copyright (C) 2004, 2009, 2010, 2011 Texas Instruments Incorporated
   5 *  Author: Aurelien Jacquiot (aurelien.jacquiot@jaluna.com)
   6 *
   7 *  Updated for 2.6.3x: Mark Salter <msalter@redhat.com>
   8 *
   9 *  This program is free software; you can redistribute it and/or modify
  10 *  it under the terms of the GNU General Public License version 2 as
  11 *  published by the Free Software Foundation.
  12 */
  13#ifndef _ASM_C6X_THREAD_INFO_H
  14#define _ASM_C6X_THREAD_INFO_H
  15
  16#ifdef __KERNEL__
  17
  18#include <asm/page.h>
  19
  20#ifdef CONFIG_4KSTACKS
  21#define THREAD_SIZE             4096
  22#define THREAD_SHIFT            12
  23#define THREAD_SIZE_ORDER       0
  24#else
  25#define THREAD_SIZE             8192
  26#define THREAD_SHIFT            13
  27#define THREAD_SIZE_ORDER       1
  28#endif
  29
  30#define THREAD_START_SP         (THREAD_SIZE - 8)
  31
  32#ifndef __ASSEMBLY__
  33
  34typedef struct {
  35        unsigned long seg;
  36} mm_segment_t;
  37
  38/*
  39 * low level task data.
  40 */
  41struct thread_info {
  42        struct task_struct      *task;          /* main task structure */
  43        unsigned long           flags;          /* low level flags */
  44        int                     cpu;            /* cpu we're on */
  45        int                     preempt_count;  /* 0 = preemptable, <0 = BUG */
  46        mm_segment_t            addr_limit;     /* thread address space */
  47};
  48
  49/*
  50 * macros/functions for gaining access to the thread information structure
  51 *
  52 * preempt_count needs to be 1 initially, until the scheduler is functional.
  53 */
  54#define INIT_THREAD_INFO(tsk)                   \
  55{                                               \
  56        .task           = &tsk,                 \
  57        .flags          = 0,                    \
  58        .cpu            = 0,                    \
  59        .preempt_count  = INIT_PREEMPT_COUNT,   \
  60        .addr_limit     = KERNEL_DS,            \
  61}
  62
  63/* get the thread information struct of current task */
  64static inline __attribute__((const))
  65struct thread_info *current_thread_info(void)
  66{
  67        struct thread_info *ti;
  68        asm volatile (" clr   .s2 B15,0,%1,%0\n"
  69                      : "=b" (ti)
  70                      : "Iu5" (THREAD_SHIFT - 1));
  71        return ti;
  72}
  73
  74#define get_thread_info(ti)     get_task_struct((ti)->task)
  75#define put_thread_info(ti)     put_task_struct((ti)->task)
  76#endif /* __ASSEMBLY__ */
  77
  78/*
  79 * thread information flag bit numbers
  80 * - pending work-to-be-done flags are in LSW
  81 * - other flags in MSW
  82 */
  83#define TIF_SYSCALL_TRACE       0       /* syscall trace active */
  84#define TIF_NOTIFY_RESUME       1       /* resumption notification requested */
  85#define TIF_SIGPENDING          2       /* signal pending */
  86#define TIF_NEED_RESCHED        3       /* rescheduling necessary */
  87#define TIF_RESTORE_SIGMASK     4       /* restore signal mask in do_signal() */
  88
  89#define TIF_MEMDIE              17      /* OOM killer killed process */
  90
  91#define TIF_WORK_MASK           0x00007FFE /* work on irq/exception return */
  92#define TIF_ALLWORK_MASK        0x00007FFF /* work on any return to u-space */
  93
  94#endif /* __KERNEL__ */
  95
  96#endif /* _ASM_C6X_THREAD_INFO_H */
  97