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Re: PCI Address Mapping


Michael Kelly wrote:
> 
> Hi,
> 
> Well I found my answer, and it's a bit ugly!
> 
> We have a hard coded window defined in the .mlt file as
> pci_window.  This insures that malloc won't take it.  Then
> for the 82559 driver, we simply use the following defines
> in the .inl file:
> 
> #define CYGHWR_INTEL_I82559_PCI_MEM_MAP_BASE 0x01F00000
> #define CYGHWR_INTEL_I82559_PCI_MEM_MAP_SIZE 0x0010000
> 
> This means that one driver eats up all of the local memory
> space assigned for PCI accesses.  If you have a second
> PCI device you're out of luck.  Unless you want to write your
> own heap manager.
> 
> Is the correct?  Is their any chance of a real heap manager
> for PCI bus mastering devices?

We've been talking about this internally - there is certainly a need for
it, and the allocator can be very simple (it never needs to free[1]). I
don't believe anyone is working on it though.

Jifl

[1] uh, well, probably :-)
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