board_memories.c

本程序是以前程序的升级

/* ----------------------------------------------------------------------------
 *         ATMEL Microcontroller Software Support 
 * ----------------------------------------------------------------------------
 * Copyright (c) 2008, Atmel Corporation
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * - Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the disclaimer below.
 *
 * Atmel's name may not be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * DISCLAIMER: THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
 * DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
 * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * ----------------------------------------------------------------------------
 */

/*
    Title: Memories implementation
*/

//------------------------------------------------------------------------------
//         Headers
//------------------------------------------------------------------------------

#include <board.h>
#include <pio/pio.h>

/*
    Macros:
        READ - Reads a register value. Useful to add trace information to read
               accesses.
        WRITE - Writes data in a register. Useful to add trace information to
                write accesses.
*/
#define READ(peripheral, register)          (peripheral->register)
#define WRITE(peripheral, register, value)  (peripheral->register = value)

//------------------------------------------------------------------------------
//         Internal definitions
//------------------------------------------------------------------------------
/*
    Constants: Remap types
        BOARD_ROM - ROM or EBI CS0 is mirrored in the remap zone.
        BOARD_RAM - RAM is mirrored in the remap zone.
*/
#define BOARD_ROM               0
#define BOARD_RAM               1

//------------------------------------------------------------------------------
//         Internal functions
//------------------------------------------------------------------------------
//------------------------------------------------------------------------------
/// Returns the current remap (see <Remap types>).
//------------------------------------------------------------------------------
static unsigned char BOARD_GetRemap( void )
{
    unsigned int *remap = (unsigned int *) 0;
    unsigned int *ram = (unsigned int *) AT91C_IRAM;

    // Try to write in 0 and see if this affects the RAM
    unsigned int temp = *ram;
    *ram = temp + 1;
    if (*remap == *ram) {

        *ram = temp;
        return BOARD_RAM;
    }
    else {

        *ram = temp;
        return BOARD_ROM;
    }
}

//------------------------------------------------------------------------------
//         Exported functions
//------------------------------------------------------------------------------
//------------------------------------------------------------------------------
/// Changes the mapping of the chip so that the remap area mirrors the
///   internal ROM or the EBI CS0.
//------------------------------------------------------------------------------
void BOARD_RemapRom()
{
    if (BOARD_GetRemap() != BOARD_ROM) {
    WRITE(AT91C_BASE_MATRIX, MATRIX_MCFG, 0);
    }
}

//------------------------------------------------------------------------------
/// Changes the mapping of the chip so that the remap area mirrors the
///   internal RAM.
//------------------------------------------------------------------------------
void BOARD_RemapRam()
{
    if (BOARD_GetRemap() != BOARD_RAM) {
    WRITE(AT91C_BASE_MATRIX, MATRIX_MCFG, (AT91C_MATRIX_RCA926I | AT91C_MATRIX_RCA926D));
    }
}

//------------------------------------------------------------------------------
/// Initialize and configure the SDRAM
//------------------------------------------------------------------------------
void BOARD_ConfigureSdram(unsigned char busWidth)
{

    volatile unsigned int i;
    static const Pin pinsSdram[] = {PINS_SDRAM};
    volatile unsigned int *pSdram = (unsigned int *) AT91C_EBI_SDRAM;
    unsigned short sdrc_dbw = 0;

    switch (busWidth) {
        case 16:
            sdrc_dbw = AT91C_SDRAMC_DBW_16_BITS;
            break;

        case 32:
        default:
            sdrc_dbw = AT91C_SDRAMC_DBW_32_BITS;
            break;

    }

    // Enable corresponding PIOs
    PIO_Configure(pinsSdram, 1);

    // Enable EBI chip select for the SDRAM
    WRITE(AT91C_BASE_MATRIX, MATRIX_EBICSA, AT91C_MATRIX_CS1A_SDRAMC);


    // CFG Control Register
    WRITE(AT91C_BASE_SDRAMC, SDRAMC_CR, AT91C_SDRAMC_NC_9
                                        | AT91C_SDRAMC_NR_13
                                        | AT91C_SDRAMC_CAS_2
                                        | AT91C_SDRAMC_NB_4_BANKS
                                        | sdrc_dbw
                                        | AT91C_SDRAMC_TWR_2
                                        | AT91C_SDRAMC_TRC_7
                                        | AT91C_SDRAMC_TRP_2
                                        | AT91C_SDRAMC_TRCD_2 
                                        | AT91C_SDRAMC_TRAS_5
                                        | AT91C_SDRAMC_TXSR_8);

    for (i = 0; i < 1000; i++);

    WRITE(AT91C_BASE_SDRAMC, SDRAMC_MR, AT91C_SDRAMC_MODE_NOP_CMD); // Perform NOP
    pSdram[0] = 0x00000000;

    WRITE(AT91C_BASE_SDRAMC, SDRAMC_MR, AT91C_SDRAMC_MODE_PRCGALL_CMD);     // Set PRCHG AL
    pSdram[0] = 0x00000000;                                         // Perform PRCHG

    for (i = 0; i < 10000; i++);

    WRITE(AT91C_BASE_SDRAMC, SDRAMC_MR, AT91C_SDRAMC_MODE_RFSH_CMD);        // Set 1st CBR
    pSdram[1] = 0x00000001;                                         // Perform CBR

    WRITE(AT91C_BASE_SDRAMC, SDRAMC_MR, AT91C_SDRAMC_MODE_RFSH_CMD);        // Set 2 CBR
    pSdram[2] = 0x00000002;                                         // Perform CBR

    WRITE(AT91C_BASE_SDRAMC, SDRAMC_MR, AT91C_SDRAMC_MODE_RFSH_CMD);        // Set 3 CBR
    pSdram[3] = 0x00000003;                                    // Perform CBR

    WRITE(AT91C_BASE_SDRAMC, SDRAMC_MR, AT91C_SDRAMC_MODE_RFSH_CMD);        // Set 4 CBR
    pSdram[4] = 0x00000004;                                   // Perform CBR

    WRITE(AT91C_BASE_SDRAMC, SDRAMC_MR, AT91C_SDRAMC_MODE_RFSH_CMD);        // Set 5 CBR
    pSdram[5] = 0x00000005;                                   // Perform CBR

    WRITE(AT91C_BASE_SDRAMC, SDRAMC_MR, AT91C_SDRAMC_MODE_RFSH_CMD);        // Set 6 CBR
    pSdram[6] = 0x00000006;                                 // Perform CBR

    WRITE(AT91C_BASE_SDRAMC, SDRAMC_MR, AT91C_SDRAMC_MODE_RFSH_CMD);        // Set 7 CBR
    pSdram[7] = 0x00000007;                                 // Perform CBR

    WRITE(AT91C_BASE_SDRAMC, SDRAMC_MR, AT91C_SDRAMC_MODE_RFSH_CMD);        // Set 8 CBR
    pSdram[8] = 0x00000008;                                 // Perform CBR

    WRITE(AT91C_BASE_SDRAMC, SDRAMC_MR, AT91C_SDRAMC_MODE_LMR_CMD);         // Set LMR operation
    pSdram[9] = 0xcafedede;                                 // Perform LMR burst=1, lat=2

    WRITE(AT91C_BASE_SDRAMC, SDRAMC_TR, (BOARD_MCK * 7) / 1000000);         // Set Refresh Timer

    WRITE(AT91C_BASE_SDRAMC, SDRAMC_MR, AT91C_SDRAMC_MODE_NORMAL_CMD);      // Set Normal mode
    pSdram[0] = 0x00000000;                                         // Perform Normal mode
}