/*
* OpenRISC Linux
*
* Linux architectural port borrowing liberally from similar works of
* others. All original copyrights apply as per the original source
* declaration.
*
* OpenRISC implementation:
* Copyright (C) 2003 Matjaz Breskvar <[email protected]>
* Copyright (C) 2010-2011 Jonas Bonn <[email protected]>
* et al.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/

#ifndef __ASM_OPENRISC_PROCESSOR_H
#define __ASM_OPENRISC_PROCESSOR_H

#include <asm/spr_defs.h>
#include <asm/page.h>
#include <asm/ptrace.h>

#define STACK_TOP TASK_SIZE
#define STACK_TOP_MAX STACK_TOP
/* Kernel and user SR register setting */
#define KERNEL_SR (SPR_SR_DME | SPR_SR_IME | SPR_SR_ICE \
| SPR_SR_DCE | SPR_SR_SM)
#define USER_SR (SPR_SR_DME | SPR_SR_IME | SPR_SR_ICE \
| SPR_SR_DCE | SPR_SR_IEE | SPR_SR_TEE)
/*
* Default implementation of macro that returns current
* instruction pointer ("program counter").
*/
#define current_text_addr() ({ __label__ _l; _l: &&_l; })

/*
* User space process size. This is hardcoded into a few places,
* so don't change it unless you know what you are doing.
*/

#define TASK_SIZE (0x80000000UL)

/* This decides where the kernel will search for a free chunk of vm
* space during mmap's.
*/
#define TASK_UNMAPPED_BASE (TASK_SIZE / 8 * 3)

#ifndef __ASSEMBLY__

struct task_struct;

struct thread_struct {
};

/*
* At user->kernel entry, the pt_regs struct is stacked on the top of the
* kernel-stack. This macro allows us to find those regs for a task.
* Notice that subsequent pt_regs stackings, like recursive interrupts
* occurring while we're in the kernel, won't affect this - only the first
* user->kernel transition registers are reached by this (i.e. not regs
* for running signal handler)
*/
#define user_regs(thread_info) (((struct pt_regs *)((unsigned long)(thread_info) + THREAD_SIZE - STACK_FRAME_OVERHEAD)) - 1)

/*
* Dito but for the currently running task
*/

#define task_pt_regs(task) user_regs(task_thread_info(task))

#define INIT_SP (sizeof(init_stack) + (unsigned long) &init_stack)

#define INIT_THREAD { }


#define KSTK_EIP(tsk) (task_pt_regs(tsk)->pc)
#define KSTK_ESP(tsk) (task_pt_regs(tsk)->sp)


void start_thread(struct pt_regs *regs, unsigned long nip, unsigned long sp);
void release_thread(struct task_struct *);
unsigned long get_wchan(struct task_struct *p);

/*
* Free current thread data structures etc..
*/

extern inline void exit_thread(void)
{
/* Nothing needs to be done. */
}

/*
* Return saved PC of a blocked thread. For now, this is the "user" PC
*/
extern unsigned long thread_saved_pc(struct task_struct *t);

#define init_stack (init_thread_union.stack)

#define cpu_relax() barrier()

#endif /* __ASSEMBLY__ */
#endif /* __ASM_OPENRISC_PROCESSOR_H */