On Fri, 17 Dec 1999, ali asad lotia wrote:
> Task:
> to get my ibm ultrastar 18es lvd drives to be recognised with 80MB/s
> interface speeds. previously using the ncr53c8xx driver using the default
> settings the drives were recognised only as fast-20 40MB/s. i initially
> tried the driver off the tekram ftp site, applied the patch to add the
> lines to the makefiles in the /drivers/scsi subdirectory in the
> linux-2.2.13 kernel source and moved the appropriate .h and .c files to
> the /drivers/scsi subdirectory. i got a kernel panic when i tried to boot
> off this kernel. the following configuration worked on this hardware. this
> was all due to the help of one Mark Schaefer. Thanks Mark.
>
> Hardware:
> Tyan 1832DL
> 2x Intel Pentium III 550
> 2x Corsair 128 MB DIMMs
> ATI Rage 128 32MB AGP video
> Intel Etherexpress Pro 100 Management PCI ethernet
> Soundblaster 16 ISA Sound card
> Tekram DC-390U2W SCSI card controlling
> 2x IBM Ultrastar 18ES LVD 9.1 GB drives at ID 0,1
>
> Distribution:
> Redhat 6.1
> Kernel 2.2.13
> compiled in sym53c8xx driver with default settings apart from SYNC which
> was set to 40.
> compiling this kernel i was able to get 80MB/s interface recognised.
If you have had a look at the driver configuration _help_ for the below
driver option, you would have read the following:
synchronous data transfers frequency
CONFIG_SCSI_NCR53C8XX_SYNC
[ ... ]
The normal answer therefore is not to go with the default but to
select the maximum value 40 allowing the driver to use the maximum
value supported by each controller. If this causes problems with
your SCSI devices, you should come back and decrease the value.
There is no safe option other than using good cabling, right
terminations and SCSI conformant devices.
There is _also_ a README.ncr53c8xx file in drivers/scsi directory that
would have explained you that the 'sync' option can be passed to both
sym53c8xx and ncr53c8xx driver from the boot command line, but may-be
this file is misplaced in the kernel tree.
BUT, if you have had a look at either the SYM53C8XX or the NCR53C8XX
kernel configuraion option you would have read the following:
Please read drivers/scsi/README.ncr53c8xx for more information.
So, nothing was missing in Linux, in my opinion, for you to be able to
configure your kernel and the proper driver for your controller according
to your needs.
G�rard.
-
To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
the body of a message to [EMAIL PROTECTED]
