flash_query.c

基于ecos的redboot

//==========================================================================
//
//      flash_query.c
//
//      Flash programming - query device
//
//==========================================================================
//####COPYRIGHTBEGIN####
//                                                                          
// -------------------------------------------                              
// The contents of this file are subject to the Red Hat eCos Public License 
// Version 1.1 (the "License"); you may not use this file except in         
// compliance with the License.  You may obtain a copy of the License at    
// http://www.redhat.com/                                                   
//                                                                          
// Software distributed under the License is distributed on an "AS IS"      
// basis, WITHOUT WARRANTY OF ANY KIND, either express or implied.  See the 
// License for the specific language governing rights and limitations under 
// the License.                                                             
//                                                                          
// The Original Code is eCos - Embedded Configurable Operating System,      
// released September 30, 1998.                                             
//                                                                          
// The Initial Developer of the Original Code is Red Hat.                   
// Portions created by Red Hat are                                          
// Copyright (C) 1998, 1999, 2000, 2001 Red Hat, Inc.
// All Rights Reserved.                                                     
// -------------------------------------------                              
//                                                                          
//####COPYRIGHTEND####
//==========================================================================
//#####DESCRIPTIONBEGIN####
//
// Author(s):    gthomas, hmt
// Contributors: gthomas
// Date:         2001-02-14
// Purpose:      
// Description:  
//              
//####DESCRIPTIONEND####
//
//==========================================================================

#include "strata.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 20*1000*10  // Approx 20ms

int
flash_query(unsigned char *data)
{
    volatile flash_t *ROM;
    int i, cnt;
    int cache_on;

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

    // Get base address and map addresses to virtual addresses
    ROM = FLASH_P2V( CYGNUM_FLASH_BASE );
#ifdef CYGOPT_FLASH_IS_BOOTBLOCK
    // BootBlock flash does not support full Read_Query - we have do a
    // table oriented thing above, after getting just two bytes of results:
    ROM[0] = FLASH_Read_ID;
    i = 2;
#else
    // StrataFlash supports the full Read_Query op:
    ROM[0] = FLASH_Read_Query;
    i = sizeof(struct FLASH_query);
#endif // Not CYGOPT_FLASH_IS_BOOTBLOCK

    for (cnt = CNT;  cnt > 0;  cnt--) ;
    for ( /* i */;  i > 0;  i-- ) {
        // It is very deliberate that data is chars NOT flash_t:
        // The info comes out in bytes regardless of device.
        *data++ = (unsigned char) (*ROM++);
#ifndef CYGOPT_FLASH_IS_BOOTBLOCK
# if  8 == CYGNUM_FLASH_WIDTH
	// strata flash with 'byte-enable' contains the configuration data
	// at even addresses
	++ROM;
# endif
#endif
    }
    ROM[0] = FLASH_Reset;

    if (cache_on) {
        HAL_DCACHE_ENABLE();
    }

    return 0;
}