CFT: msk(4) 64bit DMA support

YongHyeon PYUN pyunyh at
Wed Nov 16 19:26:24 UTC 2011

On Thu, May 26, 2011 at 06:40:43PM -0700, YongHyeon PYUN wrote:
> Hi,
> Here is a patch that implements 64bit DMA on msk(4). If you use
> msk(4) on a system that has more than 4GB memory, please try the
> patch at the following URL and let me know whether it works or not.
> You need latest msk(4) in HEAD to apply the patch.
> Previously msk(4) may have used bounce buffers on systems that have
> more than 4GB memory. You can verify whether msk(4) is using bounce
> buffers by checking the output of "sysctl hw.busdma". For instance,
> hw.busdma.zone0.total_bounced counter would increase while network
> operation is in progress.  If patch above works you wouldn't see
> the counter change anymore and it would also enhance network
> performance since it wouldn't have to copy from or to bounce
> buffers.

Committed to HEAD(r227582).

> Thanks.

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