Device timeout from mfi(9) while booting 9.2-RELEASE

[Ryan Stone]

We're having trouble booting 9.2-RELEASE on a system with an mfi
(Drake Skinny) controller.  When it tries to mount root we get:

mfi0: COMMAND 0xffffff8000cb7220 TIMEOUT AFTER 59 SECONDS
mfi0: COMMAND 0xffffff8000cb72a8 TIMEOUT AFTER 60 SECONDS
mfi0: COMMAND 0xffffff8000cb7220 TIMEOUT AFTER 90 SECONDS

I also get the following when mfi attaches (with bootverbose):

mfi0: <Drake Skinny> port 0x5000-0x50ff mem 0xfbd60000-0xfbd63fff,0xfbd00000-0xf
bd3ffff irq 16 at device 0.0 on pci2^M
mfi0: attempting to allocate 1 MSI vectors (1 supported)^M
msi: routing MSI IRQ 282 to local APIC 0 vector 77^M
mfi0: using IRQ 282 for MSI^M
mfi0: Using MSI^M
mfi0: Megaraid SAS driver Ver 4.23 ^M
mfi0: Frame 0xffffff85d394b280 timed out command 0x1010000^M
error 60 in callback from mfi_send_frame^M
mfi0: Frame 0xffffff85d394b500 timed out command 0x1040100^M
error 60 in callback from mfi_send_frame^M
mfi0: Frame 0xffffff85d394b780 timed out command 0x1040300^M
error 60 in callback from mfi_send_frame^M
mfi0: Error 255 fetching controller entries^M

I've put full bootverbose logs from boots with hw.mfi.msi=0 and
hw.mfi.msi=1 here:
http://people.freebsd.org/~rstone/mfi_timeout_irq.txt
http://people.freebsd.org/~rstone/mfi_timeout_msi.txt

Neither boot was successful.  I don't have the ability to boot from
alternative media so I have a limited ability to test changes (I can
re-image from a full disk image, but that requires building a new disk
image which takes some time).

I did see the following forum post and tried with cbb and pccard
removed from GENERIC.  That didn't fix it.
http://forums.freebsd.org/showpost.php?p=231135&postcount=4