Date: Thu, 19 Jan 1995 18:31:37 -0500 From: "Paul F. Werkowski" <pw@snoopy.MV.COM> To: hackers@FreeBSD.org Subject: Re: NEC 4xi CDROM - what now? Message-ID: <199501192331.SAA01416@snoopy.mv.com>
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Q. How can you recognize a pioneer?
A. He's one with the arrows sticking out of his a^H but.
It may be true that the NEC 4Xi is the first SCSI device to
hit FreeBSD-land that actually returns XS_BUSY status to
the Inquire command. The immediate problem is that this gets
into a code branch in scsi_base.c that looks like this:
case XS_BUSY:
/*should somehow arange for a 1 sec delay here (how?) */
/* XXX tsleep(&localvar, priority, "foo", hz);
that's how! */
case XS_TIMEOUT:
/*
* If we can, resubmit it to the adapter.
*/
if (xs->retries--) {
xs->error = XS_NOERROR;
xs->flags &= ~ITSDONE;
goto retry;
This seems to result in rapidly depleting the retry count (2) on
probe and not finding the drive.
Questions:
1. What the hell to do to correctly process the
BUSY status. The SCSI-II draft spec says try again later but
maybe some device specific thing has to happend to un-busy
the thing.
2. Does tsleep work during probe conditions? I tried it and it
seemed to have no effect. DELAY did seem to slow things down a
bit although it never got a non-busy status in 3 attempts with
10 second delays.
3. Does the re-probe feature work? (eg scsi -f /dev/sd0d -r -t2 -l0)
On this system I see an eventual response to the inquire command but
the 1740A board seems confused by the time it gets it. Any SCSI
experts make sense of this?
probe0(ahb0:2:0): scsi_cmd I think this is test_unit_ready
probe0(ahb0:2:0): ahb_scsi_cmd adapter gets called
probe0(ahb0:2:0): ahb_done adapter finished
probe0(ahb0:2:0): scsi_done 'done' processing gets called
probe0(ahb0:2:0): command: 0,0,0,0,0,0-[0 bytes] <= result
< long wait >
ahb0: board not responding <= from ahb_poll
ahb0: board not responding <= ditto
abort failed in wait
probe0(ahb0:2:0): scsi_cmd I think this is inquiry
probe0(ahb0:2:0): ahb_scsi_cmd
probe0(ahb0:2:0): ahb_done
probe0(ahb0:2:0): scsi_done
probe0(ahb0:2:0): command: 12,0,0,0,2c,0-[44 bytes]
------------------------------
000: 05 80 02 02 1f 00 00 00 4e 45 43 20 20 20 20 20 <=== looks like ok data
016: 43 44 2d 52 4f 4d 20 44 52 49 56 45 3a 35 30 31 <===
032: 32 2e 32 20 32 20 32 20 32 20 32 20 <===
------------------------------
< long wait >
ahb0: board not responding
cmd fail
ahb0: board not responding
abort failed in wait
#
Any enlightened observations would be more than welcome.
Paul
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