Re: multiple connections

["Matt Wakeley" <matt_wakeley@agilent.com>]

julian_satran@il.ibm.com wrote:

> Command numbering won't be needed anymore - every command with an
> outstanding status is restarted.

I suppose that could be done, as long as the "retry" bit was still there, so
there was no chance of a command being re-issued while the status is in flight
back to the initiator...

> As for the 2 commands - synch can be achieved by setting data first and then
> sending commands.

My point was that if there are two NICs using some kind of "mailbox" interface
to the system (like I2O), the host will have to put the data command describing
the scatter/gather list in the data NIC's mailbox, and wait for some kind of
notification that the NIC has pulled the message from the mailbox (can you say
extra unnecessary interrupt?) before it can post the command to the control
NIC's mailbox. If this synchronization was not done, there would be a small
possibility that the command could be sent to the target and the target respond
with the data before the data NIC has set itself up to receive and properly
place the data.

>
>
> Julo

-Matt