Supported chipsets in kernel 2.6.25 are Sil3124, Sil3131, Sil3132, and Sil3531.
Summary: Full TCQ/NCQ support, with full SATA control including hotplug and PM.
Use the Sil3124 if availiable as it is a nice, open design.
If a card using this driver does not seem to present individual drives to the system's BIOS for bootup purposes, re-flashing the card to the "base" (non-"raid") bios may resolve the issue. Despite documentation that says to choose "JBOD" in the raid firmware for this purpose, that option does not seem to exist in recent revisions. Card firmware is available from Silicon Image