This message is from the T13 list server.
Everyone,
It would appear that SRST is ignored in several states within the
device. I would thinkg that there would be a blanket statement about if
a FIS type 27 arrives with SRST set, not matter what state the device
transport layer is in, it should do a software reset. But I can not find
such a statement.
Examples:
A) Device is in DPIOO0, and hung for DRQ. When SRST arrives, the best
we can hope for is
that device aborts PIO, but it will still send status and go to
idle (not software reset)
The worst is that it just tosses the frame and comtinues to wait.
B) DPI001 - device is hung on trying to send PIO Setup. Note that
after host issues SYNC the
device will transition to DPIOO2 to receive data, even though the
setup failed. This also seems
like a hole in the spec.
Then the SRST arrives, and again the best we can hope for is that
the device errors out the PIO
and returns to Idle. Again without executing the SRST.
Similar issues exist in the PIO In and DMA states.
Comments from anyone?
Thanks,
Craig Stoops
Expert I/O
Your I/O Design and Verificaiton Experts
www.expertio.com
