enabling transfer negotiations, a BDR, or a bus reset to allow the controller
driver to negotiate without tagged messages getting in the way. Some
devices are confused by attempts to negotiate and tag at the same time.
Some controllers (e.g. BT MultiMaster with certain firmware revs) will
never negotiate if you don't give them an untagged "window" to perform
negotiation in.
Bump the maximum tag count to 255. The system reclaims unused tag space
as the tag count is dropped anyway, so we might as well try the max.
We should probably use a larger type than u_int8_t to hold our tag value
as SCSI over certain mediums allows for higher values.
Reviewed by: Kenneth Merry <ken@FreeBSD.org>
fd21cc5ee0