flashspecificnab.c

用于TM1300/PNX1300系列DSP（主要用于视频处理）的flash文件系统的程序源码。

/*
 *  COPYRIGHT (c) 1995,2000 TriMedia Technologies Inc. 
 *
 *   +-----------------------------------------------------------------+
 *   | THIS SOFTWARE IS FURNISHED UNDER A LICENSE AND MAY ONLY BE USED |
 *   | AND COPIED IN ACCORDANCE WITH THE TERMS AND CONDITIONS OF SUCH  |
 *   | A LICENSE AND WITH THE INCLUSION OF THE THIS COPY RIGHT NOTICE. |
 *   | THIS SOFTWARE OR ANY OTHER COPIES OF THIS SOFTWARE MAY NOT BE   |
 *   | PROVIDED OR OTHERWISE MADE AVAILABLE TO ANY OTHER PERSON. THE   |
 *   | OWNERSHIP AND TITLE OF THIS SOFTWARE IS NOT TRANSFERRED.        |
 *   +-----------------------------------------------------------------+
 *
 *  Module name              : FlashSpecificNAB.c    1.7
 *
 *  Title                    : Low level flash manipulation routines
 *
 *  Last update              : 11:38:44 - 00/06/19
 *
 *  Reviewed                 : 
 *
 *  Revision history         : 
 *
 *  Description              : Implementation of flash access functions
 *                             for Philips NAB board (containing Am29f016B).
 *
 */

/*------------------------------- Includes -----------------------------------*/

#include "tmlib/tmtypes.h"

/*************************** NAB Specific Defines *****************************/

#define MY_FLASH_BASE        0xFF400000
#define MY_SZOF_FLASH_BLOCK  0x40000
#define MY_NROF_FLASH_BLOCKS 32


#define FLASH_BASE   ((Address)MY_FLASH_BASE)

Int     SZOF_FLASH_BLOCK   = (Int)      MY_SZOF_FLASH_BLOCK;
Int     NROF_FLASH_BLOCKS  = (Int)      MY_NROF_FLASH_BLOCKS;

#define RETRY_COUNT 20


/******************************************************************************/
/*                                 FLASH erase                                */
/******************************************************************************/
Bool FLASH_block_erase(UInt ab, Bool check_if_necessary)
{
        Int i;

	volatile UInt32 *blockbase = (Pointer) ( FLASH_BASE + ab*SZOF_FLASH_BLOCK );
	volatile UInt32 *flashbase = (Pointer) FLASH_BASE;

	if (check_if_necessary) {
		Int         i;
		UInt32     *pt = (Pointer)blockbase;
		Bool        necessary = False;

		for (i = 0; i < (SZOF_FLASH_BLOCK / sizeof (Int)); i++) {
			if (*(pt++) != 0xffffffff) {
				necessary = True;
				break;
			}
		}

		if (!necessary) {
			return True;
		}
	}

        for (i=0; i<RETRY_COUNT; i++) {
		flashbase[0x555] = 0xAAAAAAAA;
		flashbase[0x2AA] = 0x55555555;
		flashbase[0x555] = 0x80808080;
		flashbase[0x555] = 0xAAAAAAAA;
		flashbase[0x2AA] = 0x55555555;
		blockbase[0x000] = 0x30303030;
	
		while ( (*blockbase ^ *blockbase) & 0x40404040) {}
	
		if ((*blockbase) == 0xffffffff) { return True; }
        }

        return False;
}

/******************************************************************************/
/*                                 FLASH write                                */
/******************************************************************************/
Bool 
FLASH_write(Pointer address, UInt32 data)
{
                 Int      i;
	volatile UInt32  *addr       = (Pointer)(FLASH_BASE+(UInt)address);
	volatile UInt32  *flashbase  = (Pointer) FLASH_BASE;
                 UInt32   old_data   = *addr;
                 UInt32   new_data   = old_data & data;

	if (new_data == old_data) {
            return data == new_data;
        }

	for (i=0; i<RETRY_COUNT; i++) {
		flashbase[0x555] = 0xAAAAAAAA;
		flashbase[0x2AA] = 0x55555555;
		flashbase[0x555] = 0xA0A0A0A0;
		*addr = new_data;

		while ( (*addr ^ *addr) & 0x40404040) {}

		if (*addr == new_data) { return True; }
	}

        return False;
}

Bool
FLASH_block_write( Pointer flash, Pointer image, Int nrof_words )
{
    Int32 *f = ((Int32*)flash) + nrof_words;
    Int32 *i = ((Int32*)image) + nrof_words;

    Bool result;

    do {
        result = FLASH_write( --f, *(--i) );
    } while ((Pointer)f != flash && result);

    return result;
}


/******************************************************************************/
/*                                 FLASH read                                 */
/******************************************************************************/
UInt32 
FLASH_read(Pointer address)
{
	UInt32 *addr= (Pointer)(FLASH_BASE+(UInt)address);

        return *addr;
}

void
FLASH_block_read( Pointer flash, Pointer image, Int nrof_words )
{
    Int32 *f = ((Int32*)flash);
    Int32 *i = ((Int32*)image);

    while (nrof_words--) {
        *(i++) = FLASH_read( f++ );
    } 
}





Bool 
FLASH_init()
{
	return True;
}