Re: [PATCH 02/02] sata_mv: workaround for multi_count errata sata24

[Mark Lord <liml@rtr.ca>]

Alan Cox wrote:
> On Mon, 13 Apr 2009 11:29:34 -0400
> Mark Lord <liml@rtr.ca> wrote:
> 
>> Workaround for errata SATA#24 in sata_mv.
>> This errata affects WRITE_MULTI* commands when
>> the device multi_count produces a DRQ block size >= 4Kbytes.
>>
>> We work around it here by converting such operations
>> into ordinary PIO_WRITEs instead.
>>
>> Note that this might result in a PIO FUA write unavoidably being converted
>> into a non-FUA write.  In practice, any system using FUA is also going to be
>> using DMA rather than PIO, so this shouldn't affect anyone in the real world.
> 
> You can just screen the FUA bit from the identify data when you do the
> drive setup to avoid that bit.
..

I think doing it at identify time would prevent DMA FUA commands,
which are fine in sata_mv.

So the only place to really hit it exactly, is at command construction
or issue time.

cheers