LXR linux/arch/cris/include/asm/processor.h

   1/*
   2 * include/asm-cris/processor.h
   3 *
   4 * Copyright (C) 2000, 2001 Axis Communications AB
   5 *
   6 * Authors:         Bjorn Wesen        Initial version
   7 *
   8 */
   9
  10#ifndef __ASM_CRIS_PROCESSOR_H
  11#define __ASM_CRIS_PROCESSOR_H
  12
  13#include <asm/system.h>
  14#include <asm/page.h>
  15#include <asm/ptrace.h>
  16#include <arch/processor.h>
  17
  18struct task_struct;
  19
  20#define STACK_TOP       TASK_SIZE
  21#define STACK_TOP_MAX   STACK_TOP
  22
  23/* This decides where the kernel will search for a free chunk of vm
  24 * space during mmap's.
  25 */
  26#define TASK_UNMAPPED_BASE      (PAGE_ALIGN(TASK_SIZE / 3))
  27
  28/* THREAD_SIZE is the size of the task_struct/kernel_stack combo.
  29 * normally, the stack is found by doing something like p + THREAD_SIZE
  30 * in CRIS, a page is 8192 bytes, which seems like a sane size
  31 */
  32
  33#define THREAD_SIZE       PAGE_SIZE
  34#define KERNEL_STACK_SIZE PAGE_SIZE
  35
  36/*
  37 * At user->kernel entry, the pt_regs struct is stacked on the top of the kernel-stack.
  38 * This macro allows us to find those regs for a task.
  39 * Notice that subsequent pt_regs stackings, like recursive interrupts occurring while
  40 * we're in the kernel, won't affect this - only the first user->kernel transition
  41 * registers are reached by this.
  42 */
  43
  44#define user_regs(thread_info) (((struct pt_regs *)((unsigned long)(thread_info) + THREAD_SIZE)) - 1)
  45
  46/*
  47 * Dito but for the currently running task
  48 */
  49
  50#define task_pt_regs(task) user_regs(task_thread_info(task))
  51#define current_regs() task_pt_regs(current)
  52
  53static inline void prepare_to_copy(struct task_struct *tsk)
  54{
  55}
  56
  57extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
  58
  59unsigned long get_wchan(struct task_struct *p);
  60
  61#define KSTK_ESP(tsk)   ((tsk) == current ? rdusp() : (tsk)->thread.usp)
  62
  63extern unsigned long thread_saved_pc(struct task_struct *tsk);
  64
  65/* Free all resources held by a thread. */
  66static inline void release_thread(struct task_struct *dead_task)
  67{
  68        /* Nothing needs to be done.  */
  69}
  70
  71#define init_stack      (init_thread_union.stack)
  72
  73#define cpu_relax()     barrier()
  74
  75#endif /* __ASM_CRIS_PROCESSOR_H */
  76