On Mon, 14 Dec 1998 16:57:05 -0500 
 Michael Richardson <mcr@solidum.com> wrote:

 >   Am I correct that there is no call like "machine_ptob()" that can be used
 > by MI device drivers that want to map memory that is on an expansion card
 > (i.e. PCI) into user space?
 >   I see that, for instance, the mmap() code for the VGA drivers is all MD.

That's correct.  I have not finished my bus_space_mmap() proposal yet.

 >   Second, due to lack of actual hardware, I'm simulating part of my card's
 > memory with system ram. Is there something I should call other than than
 > malloc() to get memory that is safe for mmap()'ing?

See bus_dma(9).

 >   Or should I really switch to using the bus_dma stuff? It isn't clear to me
 > how to do this although Jason's paper helped a lot...

Take a look at e.g. the eap audio driver.

Jason R. Thorpe                                       thorpej@nas.nasa.gov
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