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
  53 struct task_struct;
  54
  55 struct 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
  83 void start_thread(struct pt_regs *regs, unsigned long nip, unsigned long sp);
  84 void release_thread(struct task_struct *);
  85 unsigned long get_wchan(struct task_struct *p);
  86
  87 /*
  88  * Free current thread data structures etc..
  89  */
  90
  91 extern 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  */
  99 extern 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 */