On Fri, 14 Aug 1998, Eduardo E. Horvath wrote:

> On Fri, 14 Aug 1998, Chuck Cranor wrote:
> 
> > In your letter dated Fri, 14 Aug 1998 09:53:50 -0700 (PDT), you wrote:
> > >You should be using bus_dmamem_alloc() and bus_dmamem_map() for any memory
> > >that the chip will be doing DMA to/from (see dev/sbus/if_le.c).  
> > 
> > right, although it will be much more complicated for the midway
> > because the driver DMAs directly to/from the data areas of an mbuf.
> > [i.e. it doesn't do any data copying at the driver layer...]  
> > so you will have to map and unmap each mbuf you get as you receive
> > them.  i don't think bus_dmamem_alloc() will be useful since we
> > always deal with mbufs whose data areas are already allocated?
> 
> Oh, I thought it was like le in that the DMA memory was pre-allocated.
> This is much easier, even though `bus_dmamap_load_mbuf()' does not exist
> yet.

Umm- I think Jason has been working on this- it may in fact be ready
in at least the alpha port.