MMC SPI Core with FIFO

Hi,

I forgot to mention that the signal 'TRDY' is treated as the threshold of 'tx' FIFO buffer. So we need special attentions around 'TRDY', for example,

//  assign readyfordata = TRDY; 
  assign readyfordata = ~tx_fifo_full; 
//  assign write_tx_holding = data_wr_strobe & TRDY; 
  assign write_tx_holding = data_wr_strobe; 
//          if (data_wr_strobe & ~TRDY) 
          if (data_wr_strobe & tx_fifo_full) 
              // You wrote when I wasn't ready. 
              TOE <= 1; 

etc.

And there was a bug in the driver 'altspi.c'.

# ifdef MMC_SPI_FIFO
    if (hw->mode == SPI_FIFO) { 
        if (hw->txd_count < hw->len) {
            if (spsta & ALTERA_SPI_STATUS_TRDY_MSK) {        
                txd_limit = ((hw->len - hw->txd_count) > MMC_SPI_FIFO_DEPTH / 2) ? hw->txd_count + MMC_SPI_FIFO_DEPTH / 2 : hw->len;  
                for (count = hw->txd_count; count < txd_limit; count++, hw->txd_count++)
                    writel(hw_txbyte(hw, count), hw->base + ALTERA_SPI_TXDATA);
            } else {
                count = hw->txd_count++;   // <--- Here!
                writel(hw_txbyte(hw, count), hw->base + ALTERA_SPI_TXDATA);
            }
        } else {
            if (hw->count == hw->len) {
                complete(&hw->done);
            }
        }
    } else {

Kazu