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

   1/*
   2 * OpenRISC Linux
   3 *
   4 * Linux architectural port borrowing liberally from similar works of
   5 * others.  All original copyrights apply as per the original source
   6 * declaration.
   7 *
   8 * OpenRISC implementation:
   9 * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
  10 * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
  11 * et al.
  12 *
  13 * This program is free software; you can redistribute it and/or modify
  14 * it under the terms of the GNU General Public License as published by
  15 * the Free Software Foundation; either version 2 of the License, or
  16 * (at your option) any later version.
  17 */
  18
  19#ifndef __ASM_OPENRISC_PROCESSOR_H
  20#define __ASM_OPENRISC_PROCESSOR_H
  21
  22#include <asm/spr_defs.h>
  23#include <asm/page.h>
  24#include <asm/ptrace.h>
  25
  26#define STACK_TOP       TASK_SIZE
  27#define STACK_TOP_MAX   STACK_TOP
  28/* Kernel and user SR register setting */
  29#define KERNEL_SR (SPR_SR_DME | SPR_SR_IME | SPR_SR_ICE \
  30                   | SPR_SR_DCE | SPR_SR_SM)
  31#define USER_SR   (SPR_SR_DME | SPR_SR_IME | SPR_SR_ICE \
  32                   | SPR_SR_DCE | SPR_SR_IEE | SPR_SR_TEE)
  33/*
  34 * Default implementation of macro that returns current
  35 * instruction pointer ("program counter").
  36 */
  37#define current_text_addr() ({ __label__ _l; _l: &&_l; })
  38
  39/*
  40 * User space process size. This is hardcoded into a few places,
  41 * so don't change it unless you know what you are doing.
  42 */
  43
  44#define TASK_SIZE       (0x80000000UL)
  45
  46/* This decides where the kernel will search for a free chunk of vm
  47 * space during mmap's.
  48 */
  49#define TASK_UNMAPPED_BASE      (TASK_SIZE / 8 * 3)
  50
  51#ifndef __ASSEMBLY__
  52
  53struct task_struct;
  54
  55struct thread_struct {
  56};
  57
  58/*
  59 * At user->kernel entry, the pt_regs struct is stacked on the top of the
  60 * kernel-stack.  This macro allows us to find those regs for a task.
  61 * Notice that subsequent pt_regs stackings, like recursive interrupts
  62 * occurring while we're in the kernel, won't affect this - only the first
  63 * user->kernel transition registers are reached by this (i.e. not regs
  64 * for running signal handler)
  65 */
  66#define user_regs(thread_info)  (((struct pt_regs *)((unsigned long)(thread_info) + THREAD_SIZE - STACK_FRAME_OVERHEAD)) - 1)
  67
  68/*
  69 * Dito but for the currently running task
  70 */
  71
  72#define task_pt_regs(task) user_regs(task_thread_info(task))
  73
  74#define INIT_SP         (sizeof(init_stack) + (unsigned long) &init_stack)
  75
  76#define INIT_THREAD  { }
  77
  78
  79#define KSTK_EIP(tsk)   (task_pt_regs(tsk)->pc)
  80#define KSTK_ESP(tsk)   (task_pt_regs(tsk)->sp)
  81
  82
  83void start_thread(struct pt_regs *regs, unsigned long nip, unsigned long sp);
  84void release_thread(struct task_struct *);
  85unsigned long get_wchan(struct task_struct *p);
  86
  87/*
  88 * Free current thread data structures etc..
  89 */
  90
  91extern inline void exit_thread(void)
  92{
  93        /* Nothing needs to be done.  */
  94}
  95
  96/*
  97 * Return saved PC of a blocked thread. For now, this is the "user" PC
  98 */
  99extern unsigned long thread_saved_pc(struct task_struct *t);
 100
 101#define init_stack      (init_thread_union.stack)
 102
 103#define cpu_relax()     barrier()
 104
 105#endif /* __ASSEMBLY__ */
 106#endif /* __ASM_OPENRISC_PROCESSOR_H */
 107