/*
 *  Copyright 2006 by Spectrum Digital Incorporated.
 *  All rights reserved. Property of Spectrum Digital Incorporated.
 */

/*
 *  NAND Flash interface
 *
 */

#include "evmdm6437_nandflash.h"

/*
 *  Invalid Block & Page list
 */
static Uint16 invalid_blk_count = 0;
static Uint16 invalid_blks[80];

static Uint16 invalid_pg_count = 0;
static Uint16 invalid_pgs[80];

/*
 *  MFG & Device IDs
 */
static Uint8 mfg_id;
static Uint8 dev_id;

/*
 *  NAND Flash timeout
 */
static Uint32 nand_timeout = ( 0x00100000 );

/* ------------------------------------------------------------------------ *
 *                                                                          *
 *  _NAND_readECC( )                                                        *
 *                                                                          *
 *      Read ECC calcualtions                                               *
 *                                                                          *
 * ------------------------------------------------------------------------ */
#ifdef USE_ECC
    inline Uint32 _NAND_readECC( void )
    {
        return AEMIF_NANDECC2;
    }
#endif

/* ------------------------------------------------------------------------ *
 *                                                                          *
 *  _NAND_startECC( )                                                       *
 *                                                                          *
 *      Start ECC calcualtions                                              *
 *                                                                          *
 * ------------------------------------------------------------------------ */
#ifdef USE_ECC
    inline void _NAND_startECC( void )
    {
        _NAND_readECC( );
        AEMIF_NANDFCR |= 0x0100;
    }
#endif

/* ------------------------------------------------------------------------ *
 *                                                                          *
 *  _NAND_getBadPages( pages )                                              *
 *                                                                          *
 *      Get the last invaild pages                                          *
 *                                                                          *
 * ------------------------------------------------------------------------ */
void _NAND_getBadPages( Uint32* pages )
{
    Int16 i;
    for ( i = 0 ; invalid_pg_count ; i++ )
        pages[i] = invalid_pgs[i];

    if ( invalid_pg_count == 0 )
        pages[0] = 0;
}

/* ------------------------------------------------------------------------ *
 *                                                                          *
 *  _NAND_getBadBlocks( blocks )                                            *
 *                                                                          *
 *      Get the last invaild blocks                                         *
 *                                                                          *
 * ------------------------------------------------------------------------ */
void _NAND_getBadBlocks( Uint32* blocks )
{
    Int16 i;
    for ( i = 0 ; invalid_blk_count ; i++ )
        blocks[i] = invalid_blks[i];

    if ( invalid_blk_count == 0 )
        blocks[0] = 0;
}

/* ------------------------------------------------------------------------ *
 *                                                                          *
 *  _NAND_busywait( timeout )                                               *
 *                                                                          *
 *      Poll the external RDY/BSY pin                                       *
 *                                                                          *
 * ------------------------------------------------------------------------ */
Int16 _NAND_busywait( Int32 timeout )
{
    /*
     *  Short delay to let the Ready/Busy signal go LOW
     */
    _wait( 200 );

    /*
     *  Wait while the device is busy
     */
    while( ( ! NAND_READ_RB ) && ( timeout-- > 0 ) );

    if ( timeout == 0 )
        return NAND_ERR_TIMEOUT;
    else
        return 0;
}

/* ------------------------------------------------------------------------ *
 *                                                                          *
 *  _NANDFLASH_init( )                                                      *
 *      Initialize the NAND Flash                                           *
 *                                                                          *
 *  Note:                                                                   *
 *      The Write Protect on the NAND Flash is disabled.  This allows the   *
 *      erase & write NAND flash to work.                                   *
 *                                                                          *
 * ------------------------------------------------------------------------ */
Int16 EVMDM6437_NANDFLASH_init( )
{
    /*------------------------------------------------------------------*
     *                                                                  *
     *  NAND Flash timing parameters                                    *
     *                                                                  *
     *      EMIF.CLK freq   = PLL1/6 = 594/6 = 99 MHz                   *
     *      EMIF.CLK period = 1/99 MHz = 10.1 ns                        *
     *                                                                  *
     *------------------------------------------------------------------*/
    Uint32 acfg2 = 0
            | ( 0 << 31 )           // selectStrobe
            | ( 0 << 30 )           // extWait
            | ( 0 << 26 )           // writeSetup      //   0 ns
            | ( 8 << 20 )           // writeStrobe     //  40 ns
            | ( 2 << 17 )           // writeHold       //  10 ns
            | ( 0 << 13 )           // readSetup       //   0 ns
            | ( 6 << 7 )            // readStrobe      //  25 ns
            | ( 2 << 4 )            // readHold        //  10 ns
            | ( 2 << 2 )            // turnAround      //  10 ns
            | ( 0 << 0 );           // asyncSize       //  8-bit bus

    _resetEMIF( EMIF_CS2 );
    _setupEMIF( EMIF_CS2, acfg2, EMIF_NAND_MODE );

    /* ---------------------------------------------------------------- *
     *                                                                  *
     *  Note: If NANDFLASH_CE_DO_CARE is defined, then CE will be low   *
     *        during read/write/erase operations.                       *
     *                                                                  *
     *        Else if NANDFLASH_CE_DO_NOT_CARE is defined, then CE will *
     *        only be low during accesses to the NAND Flash device.     *
     *                                                                  *
     * ---------------------------------------------------------------- */

  //NAND_ASSERT_CE( );                  // Assert CE ( for CE-care devices )

    NAND_CMD( CMD_RESET );              // Reset NAND Flash

    if ( _NAND_busywait( nand_timeout ) )
        return NAND_ERR_TIMEOUT;

  //NAND_DEASSERT_CE( );                // Deassert CE ( for CE-care devices )

    return 0;
}

/* ------------------------------------------------------------------------ *
 *                                                                          *
 *  _NANDFLASH_getTotalPages( )                                             *
 *                                                                          *
 *      Determine the total number of pages of NAND Flash                   *
 *                                                                          *
 * ------------------------------------------------------------------------ */
Uint32 EVMDM6437_NANDFLASH_getTotalPages( )
{
    Uint32 pages = 0;

  //NAND_ASSERT_CE( );                  // Assert CE ( for CE-care devices )

    NAND_CMD( CMD_READID );             // Issue Read ID command
    NAND_ADDR_1( 0 );

    mfg_id = NAND_DATA;                 // Read MFG Id
    dev_id = NAND_DATA;                 // Read Device Id

    /*
     *  Compared MFG ID & Device ID to the supported devices
     */
    if ( mfg_id == MFG_SAMSUNG )
    {
        switch ( dev_id )
        {
            case DEV_K9F5608U0B:
                pages = DEV_K9F5608U0B_PAGE_COUNT;
                break;

            case DEV_K9F5608Q0B:
                pages = DEV_K9F5608Q0B_PAGE_COUNT;
                break;

            case DEV_K9F2808U0C:
                pages = DEV_K9F2808U0C_PAGE_COUNT;
                break;

            case DEV_K9K1208Q0C:
                pages = DEV_K9K1208Q0C_PAGE_COUNT;
                break;
        }
    }