When we switch to interrupt-driven command mode, test interrupt generation
with a NOP firmware command.  Broken MSI/MSI-X and interrupt line routing
problems seem to be very common, and this makes the error message much clearer
-- before this change we would mysteriously fail when initializing the QP
table.
Signed-off-by: Roland Dreier <roland@topspin.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>