locking memory ranges with the exa memory manager

[Jesse Barnes]

On Wednesday, August 10, 2005 6:00 pm, Thomas Winischhofer wrote:
> Alex Deucher wrote:
> > Unless I'm missing something, I think exa needs a function to set
> > the number and size of offscreen memory pools.  In porting exa to
> > savage, I'm having a hard time preventing the exa memory manager
> > from using the back/depth/texture buffers, etc.  XAA allows you to
> > pass a boxrect to the memory manager to specify the size of the
> > offscreen memory. how would one do that with exa?  All I can see
> > right now is limiting the size of the videoram you pass to exa.
> >
> > For example on savage the memory is laid out like this:
> >
> > start
> > -------------------------------------------------------------------
> >---------- end
> > front | offscreen | back | depth | textures | BCI queue | hwcursor
> >
> >
> > How do I limit the exa memory manager to just the offscreen
> > portion?
>
> Erm... unless I totally misunderstood your question or the whole EXA
> memory manager concept, isn't that was
> EXADriverPtr->card.offscreenBase/memorySize is for? (Provided that
> you pre-allocate back, depth, textures, BCI queue and hwcursor.)
>
> start ---------------------------------------------------------- end
> front | offscreen | back | depth | textures | BCI queue | hwcursor
>
> memoryBase        |
>
>   offscreenBase   |
>
>              memorySize
>
> (Hope you view this with a fixed width font)
>
> I don't see any reason whatsoever to specify the *real* video memory
> size in card.memorySize.

Sure, but this is a very inflexible approach.  If we could just tell EXA 
about different memory ranges, or better yet, implement the callbacks 
that Michael described in the original EXA announcement thread, it 
would be much easier to port EXA into current drivers, which tend to do 
their own memory management...

Jeses