刷好了芯片也还是很慢，1M/s传输速率。
重新买了一个新硬盘盒，GL811芯片的，速度快多了

umass0: vendor 0x05e3 USB Storage, rev 2.00/0.14, addr 2
da0 at umass-sim0 bus 0 target 0 lun 0
da0: Fixed Direct Access SCSI-0 device
da0: 40.000MB/s transfers
da0: 9590MB (19640880 512 byte sectors: 255H 63S/T 1222C)