CQHCI_TDBR
cqhci_readl(cq_host, CQHCI_TDBR),
cqhci_writel(cq_host, 1 << tag, CQHCI_TDBR);
if (!(cqhci_readl(cq_host, CQHCI_TDBR) & (1 << tag)))