processor.h

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/* MN10300 Processor specifics
 *
 * Copyright (C) 2007 Matsushita Electric Industrial Co., Ltd.
 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells ([email protected])
 *
 * 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
 */
static inline void start_thread(struct pt_regs *regs,
                unsigned long new_pc, unsigned long new_sp)
{
    regs->epsw = EPSW_nSL | EPSW_IE | EPSW_IM;
    regs->pc = new_pc;
    regs->sp = new_sp;
}


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

/*
 * 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 */