This message is from the T13 list server.
snip... for brevity... see JWW> below
> The drive vendor is responsible for making the drive as a whole act
> like a SATA drive at the terminals. Since they know they are
> integrating the devices, they certainly should have no problem
> setting up the pATA parts of the drive to always and forever be at
> the correct transfer modes given whatever bridge they choose to
> employ internally to their architecture. The OS should not have to
> issue any set transfer mode commands to a SATA drive, and any sent
> should be ignored at the drive.
JWW> But DMA mode is just the start...
1) DMA type (Multiword vs UDMA)
2) DMA Mode number
3) PIO Multi setting - Do a COMRESET and see what happens to ID Word 59
-:)
now try a write multiple with reprogramming the drive....
4) IDP (Initialize Drive Parameters)
5) ... I'm sure there are more I will find when I go review all the
things that are set by the set feature command.
Since the OS did NOT know that a Async Loss of signal happened
1) how does it know to reprogram the drive
2) On PATA you never had to reprogram the settings unless you did
a commanded HRESET
All of the OS traces I have seen (that does not include any apple, sorry
-:)
do not follow up a SRST with reprogramming all the settings as this
was not needed for PATA.
>
> While the whole notion of SATA is to fool the OS into thinking that
> is still connected to plain-old vanilla ATA disk, it just doesn't
> come out in the wash. There's really no way to completely ignore the
> SATA controller in the driver layer and do it right with a generic
> ATA disk driver. Nor is there a way to properly drive any ATA
> controller in a completely generic manner either for that matter.
>
> The whole premise of transparency is more or less a farce. It's more
> like 90% translucent.
JWW> And I am describing another piece of that missing 10% so we are in
violent agreement.
Jeff
Jeff Wolford Email: [EMAIL PROTECTED]
Senior Architect
Storage Interface and Tools - Business PC Products Group
Voice: (281) 514-9465, Pager: (800) 973-5739
Hewlett-Packard Corporation
