Hello having read various prerelease announcement on the Internet about P45 (codename: Eaglelake) I was under the impression that it supports FIS-based port multipliers (instead of just command-based). Recently, however, I read regarding the upcoming P55 chipset that among its new features is support for FIS-based PMPs on two SATA ports. Does that mean that P45 never supported FIS based PMPs?
On page 502 you will find the registers that implement FIS based switching. Their presence implies support IMHO.
The datasheet is wrong, the FIS based switching was planned originally, but Intel pulled it quietly. Infos in a linux-ide posting. But now the P55 is supposed to have FIS on two out of 6 ports, eSATA surely...