Date: Tue, 21 Nov 2000 22:15:43 +0100 (CET) From: =?ISO-8859-1?Q?G=E9rard_Roudier?= <groudier@club-internet.fr> To: "Michael C . Wu" <keichii@peorth.iteration.net> Cc: freebsd-scsi@FreeBSD.ORG Subject: Re: Sym0 not autodetecting Ultra160 Message-ID: <Pine.LNX.4.10.10011212154420.1557-100000@linux.local> In-Reply-To: <20001121071928.A75565@peorth.iteration.net>
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On Tue, 21 Nov 2000, Michael C . Wu wrote:
> Hi all,
>=20
> I have recently bought a Tekram Ultra160 U3W controller along
> with a couple IBM DDYS Ultra160 harddrives. However, I am puzzled
> by the dmesg output. It seems to say that the harddrives
> can only do 3.300MB/S transfers, when it should be saying 160.000MB/S
> The cd0 and cd1 devices both autodetect their speed correctly
>=20
> da0 at sym1 bus 0 target 2 lun 0
> da0: <IBM DDYS-T18350N S93E> Fixed Direct Access SCSI-3 device
> da0: 3.300MB/s transfers, Tagged Queueing Enabled
> da0: 17501MB (35843670 512 byte sectors: 255H 63S/T 2231C)
> da1 at sym1 bus 0 target 4 lun 0
> da1: <IBM DDYS-T18350N S93E> Fixed Direct Access SCSI-3 device
> da1: 3.300MB/s transfers, Tagged Queueing Enabled
> da1: 17501MB (35843670 512 byte sectors: 255H 63S/T 2231C)
> cd0 at sym1 bus 0 target 1 lun 0
> cd0: <PLEXTOR CD-ROM PX-40TS 1.11> Removable CD-ROM SCSI-2 device
> cd0: 20.000MB/s transfers (20.000MHz, offset 15)
> cd0: Attempt to query device size failed: NOT READY, Medium not present -=
tray closed
>=20
> Searching the archives, I find that someone had a similiary trouble
> with the ahc0 driver. He fixed it by setting the harddrive speed
> in the SCSI BIOS to the lowest possible, boot, move the speed setting
> higher, boot, until it displays 160MB/S. (i.e. 10MB/S 20M/S 40MB/s
> and so on to 160MB/S)
>=20
> I tried this, and the highest I could make it go is 40MB/S.
> After that, the kernel stays dmesg'ing at 40MB/S when I set
> the BIOS to 80MB/S or 160MB/S.
>=20
> I also tried messing with camcontrol negotiate da0 -R XXX to no avail.
>=20
> Is this just an display error? or is it really only 3.3MB/S?
All your devices are connected to the same SCSI BUS (name `sym1 bus0').
Given that the PLEXTOR CD-ROM is very unlikely to be LVD, then _all_ the=20
devices on the BUS are using SE =3D Single Ended signaling.
As a result, the maximum speed allowed is FAST-20 Wide-16 synchronous data
transfers that cannot exceed 20MB/s * 2 =3D 40 MB/s.
The Tekram U3W has 2 SCSI BUSes. One is LVD capable, allowing up to
160MB/s with Ultra-3 devices if _all_ the devices on the BUS are using LVD
signaling. The other one is only SE capable.
In result:
1) Only put LVD devices on the LVD capable channel of your controller,=20
using a LVD conformant cable with a LVD/SE terminateur at its end.
2) Connect SE devices on the other channel (BUS) which is only SE capable.
3) Configure the devices to their highest possible speed and
to their real width in the controller NVRAM for each channel
(control/c at boot).
Let me know if this fixes.
G=E9rard.
PS: I have no quite sure explanation about the 3.3MB/s async speed for
your hard disks. May-be the drive refused the negotiation for some=20
reason, or the driver tried a PPR nego. the drive disliked a lot.
Btw, in my opinion, 3.3 MB/s is the real speed. :-)=20
> Thanks,
>=20
> (Attached is my dmesg)
> --
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> | keichii@peorth.iteration.net | keichii@bsdconspiracy.net |
> | http://peorth.iteration.net/~keichii | Yes, BSD is a conspiracy. |
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>=20
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