/* MN10300 Processor specifics
 *
 * Copyright (C) 2007 Matsushita Electric Industrial Co., Ltd.
 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public Licence
 * as published by the Free Software Foundation; either version
 * 2 of the Licence, or (at your option) any later version.
 */

#ifndef _ASM_PROCESSOR_H
#define _ASM_PROCESSOR_H

#include <linux/threads.h>
#include <linux/thread_info.h>
#include <asm/page.h>
#include <asm/ptrace.h>
#include <asm/cpu-regs.h>
#include <asm/uaccess.h>
#include <asm/current.h>

/* Forward declaration, a strange C thing */
struct task_struct;
struct mm_struct;

/*
 * Default implementation of macro that returns current
 * instruction pointer ("program counter").
 */
#define current_text_addr()                     \
({                                              \
        void *__pc;                             \
        asm("mov pc,%0" : "=a"(__pc));          \
        __pc;                                   \
})

extern void get_mem_info(unsigned long *mem_base, unsigned long *mem_size);

extern void show_registers(struct pt_regs *regs);

/*
 *  CPU type and hardware bug flags. Kept separately for each CPU.
 *  Members of this structure are referenced in head.S, so think twice
 *  before touching them. [mj]
 */

struct mn10300_cpuinfo {
        int             type;
        unsigned long   loops_per_jiffy;
        char            hard_math;
};

extern struct mn10300_cpuinfo boot_cpu_data;

#ifdef CONFIG_SMP
#if CONFIG_NR_CPUS < 2 || CONFIG_NR_CPUS > 8
# error Sorry, NR_CPUS should be 2 to 8
#endif
extern struct mn10300_cpuinfo cpu_data[];
#define current_cpu_data cpu_data[smp_processor_id()]
#else  /* CONFIG_SMP */
#define cpu_data &boot_cpu_data
#define current_cpu_data boot_cpu_data
#endif /* CONFIG_SMP */

extern void identify_cpu(struct mn10300_cpuinfo *);
extern void print_cpu_info(struct mn10300_cpuinfo *);
extern void dodgy_tsc(void);
#define cpu_relax() barrier()

/*
 * User space process size: 1.75GB (default).
 */
#define TASK_SIZE               0x70000000

/*
 * Where to put the userspace stack by default
 */
#define STACK_TOP               0x70000000
#define STACK_TOP_MAX           STACK_TOP

/* This decides where the kernel will search for a free chunk of vm
 * space during mmap's.
 */
#define TASK_UNMAPPED_BASE      0x30000000

struct fpu_state_struct {
        unsigned long   fs[32];         /* fpu registers */
        unsigned long   fpcr;           /* fpu control register */
};

struct thread_struct {
        struct pt_regs          *uregs;         /* userspace register frame */
        unsigned long           pc;             /* kernel PC */
        unsigned long           sp;             /* kernel SP */
        unsigned long           a3;             /* kernel FP */
        unsigned long           wchan;
        unsigned long           usp;
        unsigned long           fpu_flags;
#define THREAD_USING_FPU        0x00000001      /* T if this task is using the FPU */
#define THREAD_HAS_FPU          0x00000002      /* T if this task owns the FPU right now */
        struct fpu_state_struct fpu_state;
};

#define INIT_THREAD             \
{                               \
        .uregs  = init_uregs,   \
        .pc     = 0,            \
        .sp     = 0,            \
        .a3     = 0,            \
        .wchan  = 0,            \
}

#define INIT_MMAP \
{ &init_mm, 0, 0, NULL, PAGE_SHARED, VM_READ | VM_WRITE | VM_EXEC, 1, \
  NULL, NULL }

/*
 * do necessary setup to start up a newly executed thread
 * - need to discard the frame stacked by the kernel thread invoking the execve
 *   syscall (see RESTORE_ALL macro)
 */
static inline void start_thread(struct pt_regs *regs,
                                unsigned long new_pc, unsigned long new_sp)
{
        struct thread_info *ti = current_thread_info();
        struct pt_regs *frame0;
        set_fs(USER_DS);

        frame0 = thread_info_to_uregs(ti);
        frame0->epsw = EPSW_nSL | EPSW_IE | EPSW_IM;
        frame0->pc = new_pc;
        frame0->sp = new_sp;
        ti->frame = frame0;
}


/* Free all resources held by a thread. */
extern void release_thread(struct task_struct *);

/* Prepare to copy thread state - unlazy all lazy status */
extern void prepare_to_copy(struct task_struct *tsk);

/*
 * create a kernel thread without removing it from tasklists
 */
extern int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);

/*
 * Return saved PC of a blocked thread.
 */
extern unsigned long thread_saved_pc(struct task_struct *tsk);

unsigned long get_wchan(struct task_struct *p);

#define task_pt_regs(task) ((task)->thread.uregs)
#define KSTK_EIP(task) (task_pt_regs(task)->pc)
#define KSTK_ESP(task) (task_pt_regs(task)->sp)

#define KSTK_TOP(info)                          \
({                                              \
        (unsigned long)(info) + THREAD_SIZE;    \
})

#define ARCH_HAS_PREFETCH
#define ARCH_HAS_PREFETCHW

static inline void prefetch(const void *x)
{
#ifdef CONFIG_MN10300_CACHE_ENABLED
#ifdef CONFIG_MN10300_PROC_MN103E010
        asm volatile ("nop; nop; dcpf (%0)" : : "r"(x));
#else
        asm volatile ("dcpf (%0)" : : "r"(x));
#endif
#endif
}

static inline void prefetchw(const void *x)
{
#ifdef CONFIG_MN10300_CACHE_ENABLED
#ifdef CONFIG_MN10300_PROC_MN103E010
        asm volatile ("nop; nop; dcpf (%0)" : : "r"(x));
#else
        asm volatile ("dcpf (%0)" : : "r"(x));
#endif
#endif
}

#endif /* _ASM_PROCESSOR_H */