Re: linux: sata_nv: adma support

["Pali Rohár" <pali.rohar@gmail.com>]

On Tuesday 25 August 2015 07:20:05 Mark Lord wrote:
> On 15-08-01 09:45 PM, Robert Hancock wrote:
> >On Sat, Aug 1, 2015 at 2:09 PM, Pali Rohár <pali.rohar@gmail.com> wrote:
> >>On Thursday 25 December 2014 07:22:13 Robert Hancock wrote:
> >>>On Tue, Dec 23, 2014 at 1:51 PM, Pali Rohár <pali.rohar@gmail.com>
> >>>wrote:
> >>>>Hello,
> >>>>
> >>>>I have nvidia nforce4 motherboard with nvidia sata controller:
> ..
> >>>It looks like something is trying to issue a command to disable APM
> >>>power management on the drive, and the command fails (likely because
> >>>it doesn't support that command).
> ..
> >>  /sbin/hdparm -B254 $DRIVE
> >>
> >>And that -B254 cause above error message in dmesg log. Output from
> >>hdparm is:
> >>
> >>  /dev/sda:
> >>   setting Advanced Power Management level to 0xfe (254)
> >>   APM_level      = not supported
> ..
> >>  $ sudo hdparm -I /dev/sda | grep -i power
> >>             *    Power Management feature set
> 
> That's not the same as APM ("Advanced" Power Management).
> 
> >However, these NVIDIA SATAs are black boxes, and rather buggy ones at that,
> >so it's possible there's an unknown issue there.
> 
> I wonder if NVIDIA simply bought out the IP from Pacific Digital
> when they went bust?  Pacific Digital invented the original "ADMA",
> and the pdc_adma.c driver in the kernel knows all about it.
> If the IP is pretty similar (identical?) then we could probably
> improve things.
> 

Can you check if nvidia ADMA code and that Pacific Digital ADMA code is
similar or not?

-- 
Pali Rohár
pali.rohar@gmail.com