ahci: sis controllers actually can do PMP
authorTejun Heo <tj@kernel.org>
Fri, 1 Aug 2008 03:51:43 +0000 (12:51 +0900)
committerJeff Garzik <jgarzik@redhat.com>
Fri, 22 Aug 2008 06:19:58 +0000 (02:19 -0400)
commit20e2de4a505aa02131a95665e8920eb053fce686
tree5711c549096723f0b6fede7bb8e4a0c7972b27b6
parentff04715bd5171d6d5c4ddff40c7bdc8d2dc90f7d
ahci: sis controllers actually can do PMP

SIS controllers were blacklisted for PMP as enabling it made device
detection fail whether the device was PMP or not - the natural
conclusion was the controller chokes on SRST w/ pmp==15.  However, it
turned out that the controller just didn't like issuing SRST after
hardreset w/o clearing SError first.  Interestingly, the SRST itself
succeeds but the following commands fail.

If SError is cleared between hardreset and SRST, which is the default
behavior now, everything works fine and SIS controllers work with PMPs
happily.

Remove PMP blacklisting for SIS AHCIs.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Piter PUNK <piterpunk@slackware.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
drivers/ata/ahci.c