uboot/cpu/arm920t/at91rm9200/spi.c
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   1/* Driver for ATMEL DataFlash support
   2 * Author : Hamid Ikdoumi (Atmel)
   3 *
   4 * This program is free software; you can redistribute it and/or
   5 * modify it under the terms of the GNU General Public License as
   6 * published by the Free Software Foundation; either version 2 of
   7 * the License, or (at your option) any later version.
   8 *
   9 * This program is distributed in the hope that it will be useful,
  10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 * GNU General Public License for more details.
  13 *
  14 * You should have received a copy of the GNU General Public License
  15 * along with this program; if not, write to the Free Software
  16 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  17 * MA 02111-1307 USA
  18 *
  19 */
  20
  21#include <config.h>
  22#include <common.h>
  23#include <asm/hardware.h>
  24
  25#ifdef CONFIG_HAS_DATAFLASH
  26#include <dataflash.h>
  27
  28#define AT91C_SPI_CLK   10000000        /* Max Value = 10MHz to be compliant to
  29                                        the Continuous Array Read function */
  30
  31/* AC Characteristics */
  32/* DLYBS = tCSS = 250ns min and DLYBCT = tCSH = 250ns */
  33#define DATAFLASH_TCSS  (0xC << 16)
  34#define DATAFLASH_TCHS  (0x1 << 24)
  35
  36#define AT91C_TIMEOUT_WRDY              200000
  37#define AT91C_SPI_PCS0_SERIAL_DATAFLASH 0xE     /* Chip Select 0: NPCS0%1110 */
  38#define AT91C_SPI_PCS3_DATAFLASH_CARD   0x7     /* Chip Select 3: NPCS3%0111 */
  39
  40/*-------------------------------------------------------------------*/
  41/*      SPI DataFlash Init                                           */
  42/*-------------------------------------------------------------------*/
  43void AT91F_SpiInit(void)
  44{
  45        /* Configure PIOs */
  46        AT91C_BASE_PIOA->PIO_ASR =
  47                AT91C_PA3_NPCS0 | AT91C_PA4_NPCS1 | AT91C_PA1_MOSI |
  48                AT91C_PA5_NPCS2 | AT91C_PA6_NPCS3 | AT91C_PA0_MISO |
  49                AT91C_PA2_SPCK;
  50        AT91C_BASE_PIOA->PIO_PDR =
  51                AT91C_PA3_NPCS0 | AT91C_PA4_NPCS1 | AT91C_PA1_MOSI |
  52                AT91C_PA5_NPCS2 | AT91C_PA6_NPCS3 | AT91C_PA0_MISO |
  53                AT91C_PA2_SPCK;
  54        /* Enable CLock */
  55        AT91C_BASE_PMC->PMC_PCER = 1 << AT91C_ID_SPI;
  56
  57        /* Reset the SPI */
  58        AT91C_BASE_SPI->SPI_CR = AT91C_SPI_SWRST;
  59
  60        /* Configure SPI in Master Mode with No CS selected !!! */
  61        AT91C_BASE_SPI->SPI_MR =
  62                AT91C_SPI_MSTR | AT91C_SPI_MODFDIS | AT91C_SPI_PCS;
  63
  64        /* Configure CS0 and CS3 */
  65        *(AT91C_SPI_CSR + 0) =
  66                AT91C_SPI_CPOL | (AT91C_SPI_DLYBS & DATAFLASH_TCSS) |
  67                (AT91C_SPI_DLYBCT & DATAFLASH_TCHS) |
  68                ((AT91C_MASTER_CLOCK / (2*AT91C_SPI_CLK)) << 8);
  69
  70        *(AT91C_SPI_CSR + 3) =
  71                AT91C_SPI_CPOL | (AT91C_SPI_DLYBS & DATAFLASH_TCSS) |
  72                (AT91C_SPI_DLYBCT & DATAFLASH_TCHS) |
  73                ((AT91C_MASTER_CLOCK / (2*AT91C_SPI_CLK)) << 8);
  74}
  75
  76void AT91F_SpiEnable(int cs)
  77{
  78        switch(cs) {
  79        case 0: /* Configure SPI CS0 for Serial DataFlash AT45DBxx */
  80                AT91C_BASE_SPI->SPI_MR &= 0xFFF0FFFF;
  81                AT91C_BASE_SPI->SPI_MR |=
  82                        ((AT91C_SPI_PCS0_SERIAL_DATAFLASH<<16) &
  83                                AT91C_SPI_PCS);
  84                break;
  85        case 3: /* Configure SPI CS3 for Serial DataFlash Card */
  86                /* Set up PIO SDC_TYPE to switch on DataFlash Card */
  87                /* and not MMC/SDCard */
  88                AT91C_BASE_PIOB->PIO_PER =
  89                        AT91C_PIO_PB7;  /* Set in PIO mode */
  90                AT91C_BASE_PIOB->PIO_OER =
  91                        AT91C_PIO_PB7;  /* Configure in output */
  92                /* Clear Output */
  93                AT91C_BASE_PIOB->PIO_CODR = AT91C_PIO_PB7;
  94                /* Configure PCS */
  95                AT91C_BASE_SPI->SPI_MR &= 0xFFF0FFFF;
  96                AT91C_BASE_SPI->SPI_MR |=
  97                        ((AT91C_SPI_PCS3_DATAFLASH_CARD<<16) & AT91C_SPI_PCS);
  98                break;
  99        }
 100
 101        /* SPI_Enable */
 102        AT91C_BASE_SPI->SPI_CR = AT91C_SPI_SPIEN; }
 103
 104/*---------------------------------------------------------------------------*/
 105/* \fn    AT91F_SpiWrite                                                     */
 106/* \brief Set the PDC registers for a transfert                              */
 107/*---------------------------------------------------------------------------*/
 108unsigned int AT91F_SpiWrite ( AT91PS_DataflashDesc pDesc )
 109{
 110        unsigned int timeout;
 111
 112        pDesc->state = BUSY;
 113
 114        AT91C_BASE_SPI->SPI_PTCR = AT91C_PDC_TXTDIS + AT91C_PDC_RXTDIS;
 115
 116        /* Initialize the Transmit and Receive Pointer */
 117        AT91C_BASE_SPI->SPI_RPR = (unsigned int)pDesc->rx_cmd_pt ;
 118        AT91C_BASE_SPI->SPI_TPR = (unsigned int)pDesc->tx_cmd_pt ;
 119
 120        /* Intialize the Transmit and Receive Counters */
 121        AT91C_BASE_SPI->SPI_RCR = pDesc->rx_cmd_size;
 122        AT91C_BASE_SPI->SPI_TCR = pDesc->tx_cmd_size;
 123
 124        if ( pDesc->tx_data_size != 0 ) {
 125                /* Initialize the Next Transmit and Next Receive Pointer */
 126                AT91C_BASE_SPI->SPI_RNPR = (unsigned int)pDesc->rx_data_pt ;
 127                AT91C_BASE_SPI->SPI_TNPR = (unsigned int)pDesc->tx_data_pt ;
 128
 129                /* Intialize the Next Transmit and Next Receive Counters */
 130                AT91C_BASE_SPI->SPI_RNCR = pDesc->rx_data_size ;
 131                AT91C_BASE_SPI->SPI_TNCR = pDesc->tx_data_size ;
 132        }
 133
 134        /* arm simple, non interrupt dependent timer */
 135        reset_timer_masked();
 136        timeout = 0;
 137
 138        AT91C_BASE_SPI->SPI_PTCR = AT91C_PDC_TXTEN + AT91C_PDC_RXTEN;
 139        while(!(AT91C_BASE_SPI->SPI_SR & AT91C_SPI_RXBUFF) &&
 140                ((timeout = get_timer_masked() ) < CONFIG_SYS_SPI_WRITE_TOUT));
 141        AT91C_BASE_SPI->SPI_PTCR = AT91C_PDC_TXTDIS + AT91C_PDC_RXTDIS;
 142        pDesc->state = IDLE;
 143
 144        if (timeout >= CONFIG_SYS_SPI_WRITE_TOUT){
 145                printf("Error Timeout\n\r");
 146                return DATAFLASH_ERROR;
 147        }
 148
 149        return DATAFLASH_OK;
 150}
 151#endif
 152