I have a F1A75-M motherboard, with A75 FCH.
I can't find documentation for this chipset on the AMD websites, but
I found on the internet, on more websites, the A75 have a FIS based SATA Portmultiplier support.
I checked the AHCI capabilities register with linux (kernel 3.2.2), and the value of this register is 0xF722FF25.
The FIS-based Switching Supported (FBSS) bit is in this register zero.
Can I download documentation for this FCH?
Has this FCH FIS-Based Swittching support?
Since you haven't gotten any replies yet on the forum, why don't you try contacting AMD customer support --
Hopefully, they can provide you with the documentation that you need.