1/*
  2 * Copyright (C) 2013 Altera Corporation
  3 * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch>
  4 * Copyright (C) 2004 Microtronix Datacom Ltd
  5 * Copyright (C) 2001 Ken Hill (khill@microtronix.com)
  6 *                    Vic Phillips (vic@microtronix.com)
  7 *
  8 * based on SPARC asm/processor_32.h which is:
  9 *
 10 * Copyright (C) 1994 David S. Miller
 11 *
 12 * This file is subject to the terms and conditions of the GNU General Public
 13 * License.  See the file "COPYING" in the main directory of this archive
 14 * for more details.
 15 */
 16
 17#ifndef _ASM_NIOS2_PROCESSOR_H
 18#define _ASM_NIOS2_PROCESSOR_H
 19
 20#include <asm/ptrace.h>
 21#include <asm/registers.h>
 22#include <asm/page.h>
 23
 24#define NIOS2_FLAG_KTHREAD	0x00000001	/* task is a kernel thread */
 25
 26#define NIOS2_OP_NOP		0x1883a
 27#define NIOS2_OP_BREAK		0x3da03a
 28
 29#ifdef __KERNEL__
 30
 31#define STACK_TOP	TASK_SIZE
 32#define STACK_TOP_MAX	STACK_TOP
 33
 34#endif /* __KERNEL__ */
 35
 36/* Kuser helpers is mapped to this user space address */
 37#define KUSER_BASE		0x1000
 38#define KUSER_SIZE		(PAGE_SIZE)
 39#ifndef __ASSEMBLY__
 40
 41/*
 42 * Default implementation of macro that returns current
 43 * instruction pointer ("program counter").
 44 */
 45#define current_text_addr() ({ __label__ _l; _l: &&_l; })
 46
 47# define TASK_SIZE		0x7FFF0000UL
 48# define TASK_UNMAPPED_BASE	(PAGE_ALIGN(TASK_SIZE / 3))
 49
 50/* The Nios processor specific thread struct. */
 51struct thread_struct {
 52	struct pt_regs *kregs;
 53
 54	/* Context switch saved kernel state. */
 55	unsigned long ksp;
 56	unsigned long kpsr;
 57};
 58
 59#define INIT_MMAP \
 60	{ &init_mm, (0), (0), __pgprot(0x0), VM_READ | VM_WRITE | VM_EXEC }
 61
 62# define INIT_THREAD {			\
 63	.kregs	= NULL,			\
 64	.ksp	= 0,			\
 65	.kpsr	= 0,			\
 66}
 67
 68extern void start_thread(struct pt_regs *regs, unsigned long pc,
 69			unsigned long sp);
 70
 71struct task_struct;
 72
 73/* Free all resources held by a thread. */
 74static inline void release_thread(struct task_struct *dead_task)
 75{
 76}
 77
 78/* Free current thread data structures etc.. */
 79static inline void exit_thread(void)
 80{
 81}
 82
 83/* Return saved PC of a blocked thread. */
 84#define thread_saved_pc(tsk)	((tsk)->thread.kregs->ea)
 85
 86extern unsigned long get_wchan(struct task_struct *p);
 87
 88#define task_pt_regs(p) \
 89	((struct pt_regs *)(THREAD_SIZE + task_stack_page(p)) - 1)
 90
 91/* Used by procfs */
 92#define KSTK_EIP(tsk)	((tsk)->thread.kregs->ea)
 93#define KSTK_ESP(tsk)	((tsk)->thread.kregs->sp)
 94
 95#define cpu_relax()	barrier()
 96#define cpu_relax_lowlatency()  cpu_relax()
 97
 98#endif /* __ASSEMBLY__ */
 99
100#endif /* _ASM_NIOS2_PROCESSOR_H */