TXD
#define NEXTTXD(i, max_mask) TXD((i) + 1, (max_mask))
#define PREVTXD(i, max_mask) TXD((i) - 1, (max_mask))
#define NTXDACTIVE(h, t, max_mask) TXD((t) - (h), (max_mask))
writel(data, nfc->regs + TXD(nbytes % 4));
writel(data, mxic->regs + TXD(nbytes % 4));