FL2440的2.6.28的内核,SD卡驱动默认是有问题的,
在linux-2.6.28.7/drivers/mmc/host目录的s3cmci.c文件的do_pio_write函数中做如下修改:
[cpp] view plaincopystatic void do_pio_write(struct s3cmci_host *host)
{
void __iomem *to_ptr;
int res; u32 fifo; u32 *ptr;
to_ptr = host->base + host->sdidata;
//while ((fifo = fifo_free(host)))
while ((fifo = fifo_free(host))>3)
//lqm changed from feiling FAE.11-01-19
{
if (!host->pio_bytes)
{
res = get_data_buffer(host, &host->pio_bytes,&host->pio_ptr);
if (res)
{
dbg(host, dbg_pio,"pio_write(): complete (no more data)./n");
host->pio_active =XFER_NONE; return;
}
dbg(host, dbg_pio,"pio_write(): new source: [%i]@[%p]/n",host->pio_bytes, host->pio_ptr);
}
/* If we have reached the end of the block, we have to * write exactly the remaining number of bytes. If we * in the middle of the block, we have to write full * words, so round down to an even multiple of 4. */
if (fifo >=host->pio_bytes)
fifo = host->pio_bytes;
else fifo -= fifo & 3;
host->pio_bytes -= fifo;
host->pio_count += fifo;
fifo = (fifo + 3) >> 2;
ptr = host->pio_ptr;
while (fifo--)
writel(*ptr++, to_ptr);
host->pio_ptr = ptr;
}
enable_imask(host, S3C2410_SDIIMSK_TXFIFOHALF);
}