target/linux/ubicom32/files/arch/ubicom32/include/asm/thread_info.h

   1 /*
   2  * arch/ubicom32/include/asm/thread_info.h
   3  *   Ubicom32 architecture low-level thread information.
   4  *
   5  * (C) Copyright 2009, Ubicom, Inc.
   6  * Adapted from the i386 and PPC versions by Greg Ungerer (gerg@snapgear.com)
   7  * Copyright (C) 2002  David Howells (dhowells@redhat.com)
   8  * - Incorporating suggestions made by Linus Torvalds and Dave Miller
   9  *
  10  * This file is part of the Ubicom32 Linux Kernel Port.
  11  *
  12  * The Ubicom32 Linux Kernel Port is free software: you can redistribute
  13  * it and/or modify it under the terms of the GNU General Public License
  14  * as published by the Free Software Foundation, either version 2 of the
  15  * License, or (at your option) any later version.
  16  *
  17  * The Ubicom32 Linux Kernel Port is distributed in the hope that it
  18  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
  19  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
  20  * the GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with the Ubicom32 Linux Kernel Port.  If not,
  24  * see <http://www.gnu.org/licenses/>.
  25  *
  26  * Ubicom32 implementation derived from (with many thanks):
  27  *   arch/m68knommu
  28  *   arch/blackfin
  29  *   arch/parisc
  30  */
  31
  32 #ifndef _ASM_UBICOM32_THREAD_INFO_H
  33 #define _ASM_UBICOM32_THREAD_INFO_H
  34
  35 #include <asm/page.h>
  36
  37 /*
  38  * Size of kernel stack for each process. This must be a power of 2...
  39  */
  40 #ifdef CONFIG_4KSTACKS
  41 #define THREAD_SIZE_ORDER (0)
  42 #else
  43 #define THREAD_SIZE_ORDER (1)
  44 #endif
  45
  46 /*
  47  * for asm files, THREAD_SIZE is now generated by asm-offsets.c
  48  */
  49 #define THREAD_SIZE (PAGE_SIZE<<THREAD_SIZE_ORDER)
  50
  51 #ifdef __KERNEL__
  52
  53 #ifndef __ASSEMBLY__
  54
  55 /*
  56  * low level task data.
  57  */
  58 struct thread_info {
  59         struct task_struct *task;               /* main task structure */
  60         struct exec_domain *exec_domain;        /* execution domain */
  61         unsigned long      flags;               /* low level flags */
  62         int                cpu;                 /* cpu we're on */
  63         int                preempt_count;       /* 0 => preemptable, <0 => BUG */
  64         int                interrupt_nesting;   /* Interrupt nesting level. */
  65         struct restart_block restart_block;
  66 };
  67
  68 /*
  69  * macros/functions for gaining access to the thread information structure
  70  */
  71 #define INIT_THREAD_INFO(tsk)                   \
  72 {                                               \
  73         .task           = &tsk,                 \
  74         .exec_domain    = &default_exec_domain, \
  75         .flags          = 0,                    \
  76         .cpu            = 0,                    \
  77         .interrupt_nesting      = 0,            \
  78         .restart_block  = {                     \
  79                 .fn = do_no_restart_syscall,    \
  80         },                                      \
  81 }
  82
  83 #define init_thread_info        (init_thread_union.thread_info)
  84 #define init_stack              (init_thread_union.stack)
  85
  86
  87 /* how to get the thread information struct from C */
  88 static inline struct thread_info *current_thread_info(void)
  89 {
  90         struct thread_info *ti;
  91
  92         asm (
  93                 "and.4  %0, sp, %1\n\t"
  94                 : "=&r" (ti)
  95                 : "d" (~(THREAD_SIZE-1))
  96                 : "cc"
  97         );
  98
  99         return ti;
 100 }
 101
 102 #define STACK_WARN (THREAD_SIZE / 8)
 103
 104 #define __HAVE_ARCH_THREAD_INFO_ALLOCATOR 1
 105
 106 /* thread information allocation */
 107 #define alloc_thread_info(tsk) ((struct thread_info *) \
 108                                 __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER))
 109 #define free_thread_info(ti)    free_pages((unsigned long) (ti), THREAD_SIZE_ORDER)
 110 #endif /* __ASSEMBLY__ */
 111
 112 #define PREEMPT_ACTIVE  0x4000000
 113
 114 /*
 115  * thread information flag bit numbers
 116  */
 117 #define TIF_SYSCALL_TRACE       0       /* syscall trace active */
 118 #define TIF_SIGPENDING          1       /* signal pending */
 119 #define TIF_NEED_RESCHED        2       /* rescheduling necessary */
 120 #define TIF_POLLING_NRFLAG      3       /* true if poll_idle() is polling
 121                                            TIF_NEED_RESCHED */
 122 #define TIF_MEMDIE              4
 123
 124 /* as above, but as bit values */
 125 #define _TIF_SYSCALL_TRACE      (1<<TIF_SYSCALL_TRACE)
 126 #define _TIF_SIGPENDING         (1<<TIF_SIGPENDING)
 127 #define _TIF_NEED_RESCHED       (1<<TIF_NEED_RESCHED)
 128 #define _TIF_POLLING_NRFLAG     (1<<TIF_POLLING_NRFLAG)
 129
 130 #define _TIF_WORK_MASK          0x0000FFFE      /* work to do on interrupt/exception return */
 131
 132 #endif /* __KERNEL__ */
 133
 134 #endif /* _ASM_UBICOM32_THREAD_INFO_H */