PCIE_IARR_1_LOWER
bcmpax_write_4(sc, PCIE_IARR_1_LOWER, iwin1_start | uimin(megs, 128));
bcmpax_write_4(sc, PCIE_IARR_1_LOWER, iwin1_start | 1);
bcmpax_write_4(sc, PCIE_IARR_1_LOWER, 0);
bcmpax_read_4(sc, PCIE_IARR_1_LOWER),