CTRL_GET
iowrite32be(FIFO_BASE + FIFO_OFFSET, priv->ctrl + CTRL_GET);
if (ioread32be(priv->ctrl + CTRL_PUT) == ioread32be(priv->ctrl + CTRL_GET))
ioread32be(priv->ctrl + CTRL_PUT), ioread32be(priv->ctrl + CTRL_GET),