flash-at45db.c

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/* Copyright (c) 2010, Ulf Kulau
 *
 * Permission is hereby granted, free of charge, to any person
 * obtaining a copy of this software and associated documentation
 * files (the "Software"), to deal in the Software without
 * restriction, including without limitation the rights to use,
 * copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following
 * conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 */

/**
 * \addtogroup Device Interfaces
 * @{
 *
 * \addtogroup AT45DB_interface
 * @{
 */

/**
 * \file
 *              Atmel Flash EEPROM AT45DB interface implementation
 * \author
 *      Ulf Kulau <kulau@ibr.cs.tu-bs.de>
 */

#include "flash-at45db.h"

int8_t at45db_init(void) {
        uint8_t i = 0, id = 0;
        /*setup buffer manager to perform write and read operations*/
        buffer_mgr.active_buffer = 0;
        buffer_mgr.buffer_addr[0] = AT45DB_BUFFER_1;
        buffer_mgr.buffer_addr[1] = AT45DB_BUFFER_2;
        buffer_mgr.buf_to_page_addr[0] = AT45DB_BUF_1_TO_PAGE;
        buffer_mgr.buf_to_page_addr[1] = AT45DB_BUF_2_TO_PAGE;
        buffer_mgr.page_program[0] = AT45DB_PAGE_PROGRAM_1;
        buffer_mgr.page_program[1] = AT45DB_PAGE_PROGRAM_2;

        mspi_chip_release(AT45DB_CS);
        /*init mspi in mode3, at chip select pin 3 and max baud rate*/
        mspi_init(AT45DB_CS, MSPI_MODE_3, MSPI_BAUD_MAX);

        while (id != 0x1F) {
                mspi_chip_select(AT45DB_CS);
                mspi_transceive(0x9F);
                id = mspi_transceive(0x00);
                mspi_chip_release(AT45DB_CS);
                _delay_ms(10);
                if (i++ > 10) {
                        return -1;
                }
        }
        return 0;

}

void at45db_erase_chip(void) {
        /*chip erase command consists of 4 byte*/
        uint8_t cmd[4] = { 0xC7, 0x94, 0x80, 0x9A };
        at45db_write_cmd(&cmd[0]);
        mspi_chip_release(AT45DB_CS);
        /*wait until AT45DB161 is ready again*/
        mspi_chip_select(AT45DB_CS);
        at45db_busy_wait();
        mspi_chip_release(AT45DB_CS);
}

void at45db_erase_block(uint16_t addr) {
        /*block erase command consists of 4 byte*/
        uint8_t cmd[4] = { AT45DB_BLOCK_ERASE, (uint8_t) (addr >> 3),
                        (uint8_t) (addr << 5), 0x00 };
        at45db_write_cmd(&cmd[0]);
        mspi_chip_release(AT45DB_CS);
        /*wait until AT45DB161 is ready again*/
        mspi_chip_select(AT45DB_CS);
        at45db_busy_wait();
        mspi_chip_release(AT45DB_CS);
}

void at45db_erase_page(uint16_t addr) {
        /*block erase command consists of 4 byte*/
        uint8_t cmd[4] = { AT45DB_PAGE_ERASE, (uint8_t) (addr >> 6),
                        (uint8_t) (addr << 2), 0x00 };
        at45db_write_cmd(&cmd[0]);
        mspi_chip_release(AT45DB_CS);
        /*wait until AT45DB161 is ready again*/
        mspi_chip_select(AT45DB_CS);
        at45db_busy_wait();
        mspi_chip_release(AT45DB_CS);
}

void at45db_write_buffer(uint16_t addr, uint8_t *buffer, uint16_t bytes) {
        uint16_t i;
        /*block erase command consists of 4 byte*/
        uint8_t cmd[4] = { buffer_mgr.buffer_addr[buffer_mgr.active_buffer], 0x00,
                        (uint8_t) (addr >> 8), (uint8_t) (addr) };

        at45db_write_cmd(&cmd[0]);

        for (i = 0; i < bytes; i++) {
                mspi_transceive(~(*buffer++));
        }

        mspi_chip_release(AT45DB_CS);
}

void at45db_buffer_to_page(uint16_t addr) {
        /*wait until AT45DB161 is ready again*/
        at45db_busy_wait();
        /*write active buffer to page command consists of 4 byte*/
        uint8_t cmd[4] = { buffer_mgr.buf_to_page_addr[buffer_mgr.active_buffer],
                        (uint8_t) (addr >> 6), (uint8_t) (addr << 2), 0x00 };
        at45db_write_cmd(&cmd[0]);
        mspi_chip_release(AT45DB_CS);
        /* switch active buffer to allow the other one to be written,
         * while these buffer is copied to the Flash EEPROM page*/
        buffer_mgr.active_buffer ^= 1;
}


void at45db_write_page(uint16_t p_addr, uint16_t b_addr, uint8_t *buffer, uint16_t bytes) {
        uint16_t i;
        /*block erase command consists of 4 byte*/
        uint8_t cmd[4] = { buffer_mgr.page_program[buffer_mgr.active_buffer],
                        (uint8_t) (p_addr >> 6), ((uint8_t) (p_addr << 2) & 0xFC) | ((uint8_t) (b_addr >> 8) & 0x3), (uint8_t) (b_addr) };

        at45db_write_cmd(&cmd[0]);

        for (i = 0; i < bytes; i++) {
                mspi_transceive(~(*buffer++));
        }

        mspi_chip_release(AT45DB_CS);

        /* switch active buffer to allow the other one to be written,
         * while these buffer is copied to the Flash EEPROM page*/
        buffer_mgr.active_buffer ^= 1;
}

void at45db_read_page_buffered(uint16_t p_addr, uint16_t b_addr,
                uint8_t *buffer, uint16_t bytes) {
        /*wait until AT45DB161 is ready again*/
        at45db_busy_wait();
        at45db_page_to_buf(p_addr);
        at45db_read_buffer(b_addr, buffer, bytes);
}

void at45db_read_page_bypassed(uint16_t p_addr, uint16_t b_addr,
                uint8_t *buffer, uint16_t bytes) {
        uint16_t i;
        /*wait until AT45DB161 is ready again*/
        at45db_busy_wait();
        /* read bytes directly from page command consists of 4 cmd bytes and
         * 4 don't care */
        uint8_t cmd[4] = { AT45DB_PAGE_READ, (uint8_t) (p_addr >> 6),
                        (((uint8_t) (p_addr << 2)) & 0xFC) | ((uint8_t) (b_addr >> 8)),
                        (uint8_t) (b_addr) };
        at45db_write_cmd(&cmd[0]);
        for (i = 0; i < 4; i++) {
                mspi_transceive(0x00);
        }
        /*now the data bytes can be received*/
        for (i = 0; i < bytes; i++) {
                *buffer++ = ~mspi_transceive(MSPI_DUMMY_BYTE);
        }
        mspi_chip_release(AT45DB_CS);
}

void at45db_page_to_buf(uint16_t addr) {

        /*write active buffer to page command consists of 4 byte*/
        uint8_t cmd[4] = { AT45DB_PAGE_TO_BUF, (uint8_t) (addr >> 6),
                        (uint8_t) (addr << 2), 0x00 };
        at45db_write_cmd(&cmd[0]);
        mspi_chip_release(AT45DB_CS);
        /* switch active buffer to allow the other one to be written,
         * while these buffer is copied to the Flash EEPROM page*/
        //buffer_mgr.active_buffer ^= 1;
        at45db_busy_wait();

}

void at45db_read_buffer(uint16_t b_addr, uint8_t *buffer, uint16_t bytes) {
        uint16_t i;
        uint8_t cmd[4] = { AT45DB_READ_BUFFER, 0x00, (uint8_t) (b_addr >> 8),
                        (uint8_t) (b_addr) };
        at45db_busy_wait();
        at45db_write_cmd(&cmd[0]);
        mspi_transceive(0x00);

        for (i = 0; i < bytes; i++) {
                *buffer++ = ~mspi_transceive(0x00);
        }
        mspi_chip_release(AT45DB_CS);
}

void at45db_write_cmd(uint8_t *cmd) {
        uint8_t i;
        mspi_chip_select(AT45DB_CS);
        for (i = 0; i < 4; i++) {
                mspi_transceive(*cmd++);
        }
}

void at45db_busy_wait(void) {
        mspi_chip_select(AT45DB_CS);
        mspi_transceive(AT45DB_STATUS_REG);
        while ((mspi_transceive(MSPI_DUMMY_BYTE) >> 7) != 0x01) {
        }
        mspi_chip_release(AT45DB_CS);
}