On Sunday 26 February 2006 14:15, Jesper Juhl wrote:
> On 2/26/06, Mark Lord <[email protected]> wrote:
> > Nick Warne wrote:
> > > I dunno what happened to the drive that time (this is the only logs of
> > > the incident) and I turned DMA back on with hdparm - but my question is
> > > why is DMA turned off and then left off after a reset?
> >
> > When I wrote that code in the mid-1990s, the number one causes of drives
> > getting confused (and needing to be reset again), were improper DMA
> > timings, cablings, and buggy DMA firmware.
> >
> > So at the time, since DMA was a newish feature for IDE, we figured that
> > turning it off after reset was a Good Thing(tm).
> >
> > And it was. A more modern implementation might try being more clever
> > about such stuff, and Tejun is working on something like that for libata.
OK, I see...
> > In the meanwhile, you could have a shell script just loop in the
> > background, turning DMA back on periodically. If you care.
I don't like - anyway, it's the first time I have ever seen this on that box
in 4 years, it was a quirk somewhere I think (maybe a power fluctuation or
the like).
> Or how about an option for the IDE driver to "not do that" that people
> could enable if needed/wanted?
> Or just change the code to "not do that" since we are no longer in the
> mid-1990s?
Good idea!
Nick
--
"Person who say it cannot be done should not interrupt person doing it."
-Chinese Proverb
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
