mvme5500: mapping vme address spaces

Eric Norum wenorum at lbl.gov
Tue Dec 29 19:37:55 UTC 2009


From the MVME550 BSP README:

The default VME configuration uses DBAT0 to map
more PCI memory space for use by the universe VME
bridge:

DBAT0
0x90000000  PCI memory space <-> VME
0x9fffffff

Port  VME-Addr   Size       PCI-Adrs   Mode:
0:    0x20000000 0x0F000000 0x90000000 A32, Dat, Sup
1:    0x00000000 0x00FF0000 0x9F000000 A24, Dat, Sup
2:    0x00000000 0x00010000 0x9FFF0000 A16, Dat, Sup

So as long as you need less than 240 MB of A32 space things should work fine.


On Dec 29, 2009, at 12:31 AM, rtwas wrote:

> Hello,
> 
> I'm looking for better insight into the process of mapping vme address spaces into
> user-app spaces.
> 
> Firstly, looking at the function: "BSP_local2vme_adrs(unsigned long am, unsigned long localaddr, unsigned long *pvmeaddr)" I see an "am" code, a "localaddr", and a "pvmeaddr" parameter, I am not seeing anyway to set the
> *window size* of the space mapped. For a the "A16" (am code: 0x29, 0x2d)  address space, it's not much of a problem since the total size of the space is relatively small.  For the "A32" space this is looking like a real problem.
> 
> Another issue/question would be: how is this space actually mapped into the programmers memory view?
> I'm assuming the mapped vme space shares the same address space as the actual program. How to know
> *where* in local space to map the desired vme space (so that I don't step on data/program memory)?
> 
> 
> Thanks.
> 
> Robert W.
> _______________________________________________
> rtems-users mailing list
> rtems-users at rtems.org
> http://www.rtems.org/mailman/listinfo/rtems-users

-- 
Eric Norum
wenorum at lbl.gov






More information about the users mailing list