Is there a way to tell u-boot (or Tianocore) on the MP30-AR0 to limit the SATA port speeds to 3Gbit instead of auto-negotiating 6Gbit? I have a case with a SATA backplane that doesn't work properly at 6Gbit, and this sometimes causes the boot to fail. If I can get it to get as far as loading the Linux kernel, it's OK as I can specify a boot parameter there to limit it, but a non-trivial fraction of the time it doesn't get that far without erroring out. TIA. Gordan