BMAC_EXCTR
stats->tx_aborted_errors += sbus_readl(bregs + BMAC_EXCTR);
(sbus_readl(bregs + BMAC_EXCTR) +
sbus_writel(0, bregs + BMAC_EXCTR);
stats->tx_aborted_errors += hme_read32(hp, bregs + BMAC_EXCTR);
(hme_read32(hp, bregs + BMAC_EXCTR) +
hme_write32(hp, bregs + BMAC_EXCTR, 0);