flash_query.c

来自「eCos操作系统源码」· C语言 代码 · 共 110 行

//==========================================================================
//
//      flash_query.c
//
//      Flash programming - query device
//
//==========================================================================
//####ECOSGPLCOPYRIGHTBEGIN####
// -------------------------------------------
// This file is part of eCos, the Embedded Configurable Operating System.
// Copyright (C) 1998, 1999, 2000, 2001, 2002 Red Hat, Inc.
//
// eCos 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 or (at your option) any later version.
//
// eCos is distributed in the hope that it will be useful, but WITHOUT ANY
// WARRANTY; without even the implied warranty of MERCHANTABILITY or
// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
// for more details.
//
// You should have received a copy of the GNU General Public License along
// with eCos; if not, write to the Free Software Foundation, Inc.,
// 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
//
// As a special exception, if other files instantiate templates or use macros
// or inline functions from this file, or you compile this file and link it
// with other works to produce a work based on this file, this file does not
// by itself cause the resulting work to be covered by the GNU General Public
// License. However the source code for this file must still be made available
// in accordance with section (3) of the GNU General Public License.
//
// This exception does not invalidate any other reasons why a work based on
// this file might be covered by the GNU General Public License.
//
// Alternative licenses for eCos may be arranged by contacting Red Hat, Inc.
// at http://sources.redhat.com/ecos/ecos-license/
// -------------------------------------------
//####ECOSGPLCOPYRIGHTEND####
//==========================================================================
//#####DESCRIPTIONBEGIN####
//
// Author(s):    gthomas
// Contributors: gthomas
// Date:         2001-07-17
// Purpose:      
// Description:  
//              
//####DESCRIPTIONEND####
//
//==========================================================================

#include "flash.h"

#include <pkgconf/hal.h>
#include <cyg/hal/hal_arch.h>
#include <cyg/hal/hal_cache.h>
#include CYGHWR_MEMORY_LAYOUT_H

//
// CAUTION!  This code must be copied to RAM before execution.  Therefore,
// it must not contain any code which might be position dependent!
//

#define CNT 2000*1000*10  // At least 20ms

int
flash_query(unsigned short *data)
{
    volatile unsigned short *ROM;
    int cnt, cache_on;

    HAL_DCACHE_IS_ENABLED(cache_on);
    if (cache_on) {
        HAL_DCACHE_SYNC();
        HAL_DCACHE_DISABLE();
    }

    ROM = (volatile unsigned short *)0x01010000;

    // Send lead-in sequence
    ROM[FLASH_Key_Addr0] = FLASH_Key0;
    ROM[FLASH_Key_Addr1] = FLASH_Key1;

    // Send 'identify' command
    ROM[FLASH_Key_Addr0] = FLASH_Read_ID;

    // Need a delay of 20ms!
    for (cnt = 0;  cnt < 50000;  cnt++) ;

    data[0] = ROM[0];  // Manufacturer code
    data[1] = ROM[1];  // Device identifier

    // Send lead-in sequence
    ROM[FLASH_Key_Addr0] = FLASH_Key0;
    ROM[FLASH_Key_Addr1] = FLASH_Key1;

    // Send 'reset' command
    ROM[FLASH_Key_Addr0] = FLASH_Reset;

    // Need a delay of 20ms!
    for (cnt = 0;  cnt < 50000;  cnt++) ;

    if (cache_on) {
        HAL_DCACHE_ENABLE();
    }

    return 0;
}