dataflash.c

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#include "dataflash.h"
#include <appconfig.h>

#include <cfg/macros.h>
#include <cfg/debug.h>
#include <cfg/module.h>
#include <drv/timer.h>
#include <kern/kfile.h>

#if CONFIG_KERNEL
#include <kern/proc.h>
#endif

#include <string.h>

static const DataflashInfo mem_info[] =
{
    {
        /* AT45DB041B */
        .density_id = 0x07,
        .page_size = 264,
        .page_bits = 9,
        .page_cnt = 2048,
        .read_cmd = DFO_READ_FLASH_MEM_BYTE_B,
    },
    {
        /* AT45DB081D */
        .density_id = 0x09,
        .page_size = 264,
        .page_bits = 9,
        .page_cnt = 4096,
        .read_cmd = DFO_READ_FLASH_MEM_BYTE_D,
    },
    {
        /* AT45DB161D */
        .density_id = 0x0B,
        .page_size = 528,
        .page_bits = 10,
        .page_cnt = 4096,
        .read_cmd = DFO_READ_FLASH_MEM_BYTE_D,
    },
    /* Add other memories here */
};

STATIC_ASSERT(countof(mem_info) == DFT_CNT);

INLINE void CS_TOGGLE(KFileDataflash *fd)
{
    fd->setCS(false);
    fd->setCS(true);
}

static void send_cmd(KFileDataflash *fd, dataflash_page_t page_addr, dataflash_offset_t byte_addr, DataFlashOpcode opcode)
{

    /*
     * Make sure to toggle CS signal in order,
     * and reset dataflash command decoder.
     */
    CS_TOGGLE(fd);


    /*
     * To send one command to data flash memory, we send 4 byte.
     * First byte is opcode command, second and third byte are
     * page address, in last byte we write a byte page address.
     * (see datasheet for more detail).
     *
     * \note Generaly a defaul memory page size is more than 256 byte.
     *  In this case we need for addressing a byte in one page more than
     *  8 bit, so we put in fourth byte low part of address byte, and
     *  hight part of address byte in third byte togheter low par of page
     *  address.
     *
     */

    /*
     * Send opcode.
     */
    kfile_putc(opcode, fd->channel);

    /*
     *  Send page address.
     */
    kfile_putc((uint8_t)(page_addr >> (16 - mem_info[fd->dev].page_bits)), fd->channel);
    kfile_putc((uint8_t)((page_addr << (mem_info[fd->dev].page_bits - 8)) + (byte_addr >> 8)), fd->channel);

    /*
     * Send byte page address.
     */
    kfile_putc((uint8_t)byte_addr, fd->channel);
}

static void dataflash_reset(KFileDataflash *fd)
{
    fd->setCS(false);

    if (fd->setReset)
    {
        fd->setReset(true);
        timer_delayHp(us_to_hptime(RESET_PULSE_WIDTH));
        fd->setReset(false);
        timer_delayHp(us_to_hptime(RESET_PULSE_WIDTH));
    }
}


static uint8_t dataflash_stat(KFileDataflash *fd)
{
    /*
     * Make sure to toggle CS signal
     * and reset dataflash command decoder.
     */
    CS_TOGGLE(fd);

    kfile_putc(DFO_READ_STATUS, fd->channel);

    return kfile_getc(fd->channel);
}


static uint8_t dataflash_cmd(KFileDataflash *fd, dataflash_page_t page_addr, dataflash_offset_t byte_addr, DataFlashOpcode opcode)
{
    uint8_t stat;

    send_cmd(fd, page_addr, byte_addr, opcode);

    CS_TOGGLE(fd);

    /*
     * We chech data flash memory state, and wait until busy-flag
     * is high.
     */
    while (!(dataflash_stat(fd) & BUSY_BIT))
    {
        #if CONFIG_KERNEL
        proc_switch();
        #endif
    }

    stat = dataflash_stat(fd);

    kfile_flush(fd->channel); // Flush channel
    /*
     * Data flash has completed a bus cycle, so disable CS.
     */
    fd->setCS(false);

    return stat;
}

static void dataflash_readBlock(KFileDataflash *fd, dataflash_page_t page_addr, dataflash_offset_t byte_addr, DataFlashOpcode opcode, uint8_t *block, dataflash_size_t len)
{
    send_cmd(fd, page_addr, byte_addr, opcode);

    if (opcode == DFO_READ_FLASH_MEM_BYTE_B)
    {
        /*
         * Send 24 don't care bits.
         */
        uint8_t dummy[] = { 0, 0, 0 };
        kfile_write(fd->channel, dummy, sizeof(dummy));
    }

    kfile_putc(0, fd->channel); //Send 8 don't care bit.
    kfile_read(fd->channel, block, len); //Read len bytes ad put in block buffer.
    kfile_flush(fd->channel); // Flush channel
    fd->setCS(false);
}


static void dataflash_writeBlock(KFileDataflash *fd, dataflash_offset_t offset, DataFlashOpcode opcode, const uint8_t *block, dataflash_size_t len)
{
    ASSERT(offset + len <= mem_info[fd->dev].page_size);

    send_cmd(fd, 0x00, offset, opcode);

    kfile_write(fd->channel, block, len); //Write len bytes.
    kfile_flush(fd->channel); // Flush channel

    fd->setCS(false);
}


static void dataflash_loadPage(KFileDataflash *fd, dataflash_page_t page_addr)
{
    dataflash_cmd(fd, page_addr, 0x00, DFO_MOV_MEM_TO_BUFF1);
}

static int dataflash_flush(KFile *_fd)
{
    KFileDataflash *fd = KFILEDATAFLASH(_fd);
    if (fd->page_dirty)
    {
        dataflash_cmd(fd, fd->current_page, 0x00, DFO_WRITE_BUFF1_TO_MEM_E);

        fd->page_dirty = false;

        kprintf("Flushing page <%ld>\n", fd->current_page);
    }
    return 0;
}

/* Kfile interface section */

static int dataflash_close(struct KFile *_fd)
{
    dataflash_flush(_fd);
    TRACE;
    return 0;
}

static KFile *dataflash_reopen(KFile *_fd)
{
    KFileDataflash *fd = KFILEDATAFLASH(_fd);
    dataflash_close(_fd);

    fd->current_page = 0;
    fd->fd.seek_pos = 0;

    /* Load selected page from dataflash memory */
    dataflash_loadPage(fd, fd->current_page);

    TRACE;
    return &fd->fd;
}


static size_t dataflash_read(struct KFile *_fd, void *buf, size_t size)
{
    KFileDataflash *fd = KFILEDATAFLASH(_fd);

    dataflash_offset_t byte_addr;
    dataflash_page_t page_addr;
    uint8_t *data = (uint8_t *)buf;


    ASSERT(fd->fd.seek_pos + size <= fd->fd.size);
    size = MIN((uint32_t)size, fd->fd.size - fd->fd.seek_pos);

    kprintf("Reading at pos[%lu]\n", fd->fd.seek_pos);

    /*
     * We select page and offest from absolute address.
     */
    page_addr = fd->fd.seek_pos / mem_info[fd->dev].page_size;
    byte_addr = fd->fd.seek_pos % mem_info[fd->dev].page_size;

    kprintf("[page-<%ld>, byte-<%ld>]", page_addr, byte_addr);

    /*
     * Flush current page in main memory if
     * we had been written a byte in memory
     */
    dataflash_flush(&fd->fd);

    /*
     * Read byte in main page data flash memory.
     */
    dataflash_readBlock(fd, page_addr, byte_addr, mem_info[fd->dev].read_cmd, data, size);

    fd->fd.seek_pos += size;
    kprintf("Read %ld bytes\n", size);

    return size;
}

static size_t dataflash_write(struct KFile *_fd, const void *_buf, size_t size)
{
    KFileDataflash *fd = KFILEDATAFLASH(_fd);

    dataflash_offset_t offset;
    dataflash_page_t new_page;
    size_t total_write = 0;

    const uint8_t *data = (const uint8_t *) _buf;

    ASSERT(fd->fd.seek_pos + size <= fd->fd.size);
    size = MIN((uint32_t)size, fd->fd.size - fd->fd.seek_pos);

    kprintf("Writing at pos[%lu]\n", fd->fd.seek_pos);

    while (size)
    {
        /*
        * We select page and offest from absolute address.
        */
        new_page = fd->fd.seek_pos / mem_info[fd->dev].page_size;
        offset = fd->fd.seek_pos % mem_info[fd->dev].page_size;


        size_t wr_len = MIN(size, mem_info[fd->dev].page_size - offset);

        kprintf(" [page-<%ld>, byte-<%ld>]",new_page, offset);

        if (new_page != fd->current_page)
        {
            /* Flush current page in main memory*/
            dataflash_flush(&fd->fd);
            /* Load select page memory from data flash memory*/
            dataflash_loadPage(fd, new_page);

            fd->current_page = new_page;
            kprintf(" >> Load page: <%ld> ", new_page);
        }
        /*
        * Write byte in current page, and set true
        * page_dirty flag.
        */
        dataflash_writeBlock(fd, offset, DFO_WRITE_BUFF1, data, wr_len);
        fd->page_dirty = true;

        data += wr_len;
        fd->fd.seek_pos += wr_len;
        size -= wr_len;
        total_write += wr_len;
    }

    kprintf("written %lu bytes\n", total_write);
    return total_write;
}

MOD_DEFINE(dataflash);

bool dataflash_init(KFileDataflash *fd, KFile *ch, DataflashType dev, dataflash_setCS_t *setCS, dataflash_setReset_t *setReset)
{
    uint8_t stat;

    MOD_CHECK(hw_dataflash);

    ASSERT(fd);
    ASSERT(ch);
    ASSERT(setCS);
    ASSERT(dev < DFT_CNT);

    memset(fd, 0, sizeof(*fd));
    DB(fd->fd._type = KFT_DATAFLASH);
    fd->dev = dev;
    fd->channel = ch;
    fd->setReset = setReset;
    fd->setCS = setCS;

    // Setup data flash programming functions.
    fd->fd.reopen = dataflash_reopen;
    fd->fd.close = dataflash_close;
    fd->fd.read = dataflash_read;
    fd->fd.write = dataflash_write;
    fd->fd.seek = kfile_genericSeek;
    fd->fd.flush = dataflash_flush;

    dataflash_reset(fd);

    stat = dataflash_stat(fd);

    /*
     * 2,3,4,5 bits of 1 byte status register
     * indicate a device density of dataflash memory
     * (see datasheet for more detail.)
     */
    if (GET_ID_DESITY_DEVICE(stat) != mem_info[fd->dev].density_id)
        return false;

    fd->current_page = 0;
    fd->fd.seek_pos = 0;
    fd->fd.size = mem_info[fd->dev].page_size * mem_info[fd->dev].page_cnt;

    /* Load selected page from dataflash memory */
    dataflash_loadPage(fd, fd->current_page);
    MOD_INIT(dataflash);
    return true;
}