[PATCH v2 00/15] PCI io.h clean-up

Arnd Bergmann arnd at arndb.de
Mon Jul 16 05:17:09 EDT 2012


On Monday 16 July 2012, Andrew Lunn wrote:
> The changes you made for Orion decreased the window to 64K. However, i
> see here that PCI0 only gets 60K, where as PCI1 gets the full 64K.
> 
> Is this asymmetry correct?
> 
> I see this for both orion5x and kirkwood.

The range from 0x0-0xfff is used for ISA-style devices, including those
behind a PCI bridge or emulating one like a VGA text console or an
IDE controller. We set PCIBIOS_MIN_IO to 0x1000 to avoid conflicts
between those and dynamically probed PCI devices that we might otherwise
put in the same range.

	Arnd




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