/*
* Copyright (C) 2008-2009 Michal Simek <[email protected]>
* Copyright (C) 2008-2009 PetaLogix
* Copyright (C) 2006 Atmark Techno, Inc.
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/

#ifndef _ASM_MICROBLAZE_PROCESSOR_H
#define _ASM_MICROBLAZE_PROCESSOR_H

#include <asm/ptrace.h>
#include <asm/setup.h>
#include <asm/registers.h>
#include <asm/entry.h>
#include <asm/current.h>

# ifndef __ASSEMBLY__
/* from kernel/cpu/mb.c */
extern const struct seq_operations cpuinfo_op;

# define cpu_relax() barrier()

#define task_pt_regs(tsk) \
(((struct pt_regs *)(THREAD_SIZE + task_stack_page(tsk))) - 1)

/* Do necessary setup to start up a newly executed thread. */
void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long usp);

extern void ret_from_fork(void);
extern void ret_from_kernel_thread(void);

# endif /* __ASSEMBLY__ */

# ifndef CONFIG_MMU
/*
* User space process size: memory size
*
* TASK_SIZE on MMU cpu is usually 1GB. However, on no-MMU arch, both
* user processes and the kernel is on the same memory region. They
* both share the memory space and that is limited by the amount of
* physical memory. thus, we set TASK_SIZE == amount of total memory.
*/
# define TASK_SIZE (0x81000000 - 0x80000000)

/*
* Default implementation of macro that returns current
* instruction pointer ("program counter").
*/
# define current_text_addr() ({ __label__ _l; _l: &&_l; })

/*
* This decides where the kernel will search for a free chunk of vm
* space during mmap's. We won't be using it
*/
# define TASK_UNMAPPED_BASE 0

/* definition in include/linux/sched.h */
struct task_struct;

/* thread_struct is gone. use thread_info instead. */
struct thread_struct { };
# define INIT_THREAD { }

/* Free all resources held by a thread. */
static inline void release_thread(struct task_struct *dead_task)
{
}

/* Free all resources held by a thread. */
static inline void exit_thread(void)
{
}

extern unsigned long thread_saved_pc(struct task_struct *t);

extern unsigned long get_wchan(struct task_struct *p);

# define KSTK_EIP(tsk) (0)
# define KSTK_ESP(tsk) (0)

# else /* CONFIG_MMU */

/*
* This is used to define STACK_TOP, and with MMU it must be below
* kernel base to select the correct PGD when handling MMU exceptions.
*/
# define TASK_SIZE (CONFIG_KERNEL_START)

/*
* 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)

# define THREAD_KSP 0

# ifndef __ASSEMBLY__

/*
* Default implementation of macro that returns current
* instruction pointer ("program counter").
*/
# define current_text_addr() ({ __label__ _l; _l: &&_l; })

/* If you change this, you must change the associated assembly-languages
* constants defined below, THREAD_*.
*/
struct thread_struct {
/* kernel stack pointer (must be first field in structure) */
unsigned long ksp;
unsigned long ksp_limit; /* if ksp <= ksp_limit stack overflow */
void *pgdir; /* root of page-table tree */
struct pt_regs *regs; /* Pointer to saved register state */
};

# define INIT_THREAD { \
.ksp = sizeof init_stack + (unsigned long)init_stack, \
.pgdir = swapper_pg_dir, \
}

/* Free all resources held by a thread. */
extern inline void release_thread(struct task_struct *dead_task)
{
}

/* Free current thread data structures etc. */
static inline void exit_thread(void)
{
}

/* Return saved (kernel) PC of a blocked thread. */
# define thread_saved_pc(tsk) \
((tsk)->thread.regs ? (tsk)->thread.regs->r15 : 0)

unsigned long get_wchan(struct task_struct *p);

/* The size allocated for kernel stacks. This _must_ be a power of two! */
# define KERNEL_STACK_SIZE 0x2000

/* Return some info about the user process TASK. */
# define task_tos(task) ((unsigned long)(task) + KERNEL_STACK_SIZE)
# define task_regs(task) ((struct pt_regs *)task_tos(task) - 1)

# define task_pt_regs_plus_args(tsk) \
((void *)task_pt_regs(tsk))

# define task_sp(task) (task_regs(task)->r1)
# define task_pc(task) (task_regs(task)->pc)
/* Grotty old names for some. */
# define KSTK_EIP(task) (task_pc(task))
# define KSTK_ESP(task) (task_sp(task))

/* FIXME */
# define deactivate_mm(tsk, mm) do { } while (0)

# define STACK_TOP TASK_SIZE
# define STACK_TOP_MAX STACK_TOP

#ifdef CONFIG_DEBUG_FS
extern struct dentry *of_debugfs_root;
#endif

# endif /* __ASSEMBLY__ */
# endif /* CONFIG_MMU */
#endif /* _ASM_MICROBLAZE_PROCESSOR_H */