Re: MMU questions?

[Julian Reschke-FJR010 <Julian_Reschke-FJR010@email.mot.com>]

rincewind@tubul.dascon.de%INTERNET wrote:
> 
> On Wed, Jun 03, 1998 at 12:25:33PM +0000, Jesús Cea Avión wrote:
> 
> > MMU. Devices don´t know. So you can´t use virtual memory for DMA audio
> > playing/Hard Disk or Video Memory for the Videl. AFAIK, ALT/TT Ram
> > distintion is to allow the system to know about memory that can´t
> > allocate for such things.
> 
> Actually, you *can* do DMA etc. in virtual memory - however, the driver
> which handles the device doing DMA must be VM-aware and translate logical to
> physical addresses when programming the DMA controller.

Of course.

However I would argue that in this case you are using physical memory
:-)