Re: esp_scsi QTAG in FAS216

David Miller
2014-04-07T03:39:24Z

From: Michael Schmitz <schmitzmic@gmail.com>
Date: Mon, 7 Apr 2014 08:33:12 +1200

> Hello Dave, Tuomas,
>
>>> Also, looking at the timeout formulae in the old NCR53C9x.c driver,
>>> the values would be different for FAS216. Why was this dropped from
>>> the modern esp_scsi?
>>
>> I've never seen a formula for any ESP or FAS chip for the timeout
>> other than the one mentioned in huge comment in
>> esp_set_clock_params(), although I do see the 7668 instead of 8192
>> factor being used in the old NCR53C9x driver.
>
> I haven't gone far enough back in the 53C9x revision history to be
> certain. but it would seem to me that Kars de Jong added that FAS
> special case.
>
> Can you confirm that, Kars? Any recollection as to the reason?

Just as another reference point, I looked at the FreeBSD 'esp' driver
and it also uses the 8192 factor for all chips, including FAS216.