Re: [PATCH libata-dev-2.6 1/3] Add CHS support

[Mark Lord <mlord@pobox.com>]

The exact sequence expected by certain pre-ATA4 (or earlier?) drives
was this:

SRST RESET
IDENTIFY
INITIALIZE DRIVE PARAMETERS
anything else..

Some drives were very specific about that exact sequence.

Nowadays, I don't bother with it for anything new I do,
as it is obsolete, and may even get rejected by modern drives.
But for the mainstream Linux ATA support, we should issue it
for drives which IDENTIFY themselves as conforming to pre-ATAx,
where the safest value for "x" is probably "4".

Cheers
-- 
Mark Lord
Real-Time Remedies Inc.
mlord@pobox.com

Jeff Garzik wrote:
> Mark Lord wrote:
> 
>> Jeff Garzik wrote:
>>
>>> 3) In Promise's GPL'd driver for their SATA (w/ PATA) cards, they 
>>> unconditionally execute the INITIALIZE DEVICE PARAMETERS command.  I 
>>> wonder if we should do the same.
>>
>>
>>
>> That command was *necessary* for certain drives at one time,
>> which refused all other commands until they received the IDP one.
> 
> 
> Except IDENTIFY DEVICE, presumably?
> 
> Thanks,
> 
>     Jeff
>