Re: dma errors

[David Baron <d_baron@012.net.il>]

On Thursday 27 July 2006 00:38, Daniel B. wrote:
> Greg Madden wrote:
> ...
>
> > John Schmidt <jaschmidt@uofu.net> wrote:
>
> ...
>
> >> I have two IDE drives ...  the motherboard is quite old.
>
> ...
>
> >> I get the following error messages from dmesg:
>
> ...>> hde: dma_intr: status=0x51 { DriveReady SeekComplete Error }
>
> >> hde: dma_intr: error=0x84 { DriveStatusError BadCRC }
> >> ide: failed opcode was: unknown
> >> hde: dma_timer_expiry: dma status == 0x20
> >> hde: DMA timeout retry
> >> PDC202XX: Primary channel reset.
> >> PDC202XX: Secondary channel reset.
> >> hde: timeout waiting for DMA
> >> hde: dma_timer_expiry: dma status == 0x21
> >> hde: DMA timeout error
> >> hde: dma timeout error: status=0x58 { DriveReady SeekComplete
> >> DataRequest } ide: failed opcode was: unknown
>
> ...
>
> >> What would be the source of these errors and how should I go about
> >> fixing them?
> >
> > A couple of things, the generic IDE driver doesn't do dma , make sure
> > you load the module for your chipset. Using 'hdparm' will
> > show if dma is set for the drives.
>
> Greg:
>
> Clearly John's driver is doing DMA; otherwise all the DMA errors
> wouldn't be present.
>
>
> John:
>
> Which motherboard do you have?
>
> I have had similar problems with an Asus A7M266-D motherboard with multiple
> kernel versions (2.2 through 2.6, I think).
>
>  From what I've been able to gather, my motherboard's IDE controller (AMD
> 768?) is buggy, and the Linux kernel doesn't do whatever the Windows
> kernel does to work around the problem.
>
> (I can't run the disks attached to the onboard IDE controller at full
> sped (i.e., with DMA on) or I get extreme filesystem corruption in Linux.
> Under Windows, I can run a seemingly full speed without any data-
> corruption problems.)

Check the cables!