Re: [Qemu-devel] enabling bus-master IDE driver

[zitu]

Quoting James Boddington <address@hidden>:
> James Boddington wrote:
>
> > I found 2000 is using pio as well.
> >
>
> I'll change that. It is with 2000 + sp4. I am getting pio on the primary
> ide and dma on the secondary ide channel.
>

on xp, it's PIO for both. DMA if available only on primary (hdd).

For linux guest, as root, hdparm -d0/-d1 doesn't work.

But with the DMA patch, you should see DMA is on with the following:
'hdparm /dev/hda'
It's also visible in /proc/ide/hda/settings :)

Based on the microsoft link I was sent yesterday, and numerous experiments,
win95 native 82371SB driver is not working with qemu. The debug hint
sent yesterday show dma capability at low level, but DMA is always
disabled inside hardware manager.

Low level debug show real DMA access for both bbs-2.1 and dls-0.8.0
It's not just a kernel message or a hdparm.

This is an output of a linux session (dsl)
      1 WIN_READ
      1 WIN_READ_NATIVE_MAX
      1 WIN_RECAL
      1 WIN_SETMULT
      1 WIN_SPECIFY
      2 WIN_PIDENTIFY
      4 WIN_IDENTIFY
    240 WIN_PACKETCMD
   2503 WIN_READDMA

If we had the win95 driver sources for 82371SB, we could find what is
missing inside qemu's code "to please microsoft" guests.

Zitu
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