Another OCP enet patch

Dan Malek dan at embeddededge.com
Thu May 30 00:51:21 EST 2002


David Gibson wrote:

> Well, actually, dma_cache_wback() and friends still appear to be more
> widely used than consistent_sync().  AFAICT only PPC and ARM use
> consistent_sync().

Just for a historical note.....these functions were implemented about
the same time to support non-PCI USB controllers.  They have found other
uses since then.  Other architectures seem to assume PCI is always present,
and will call the dma_cache_* functions within the pci functions to get
the same effect.  For non-PCI devices, they still call the pci functions
with a null pointer for the pci_dev.  On PPC and ARM we had systems that
wouldn't compile properly with PCI enabled, since there wasn't any PCI
bridge support (even fake ones :-).  We just added the consistent_sync()
to be orthogonal with the other archtecture independent consistent_* functions.
The other architectures are moving this way as they are finding it more
difficult to continue to fake a PCI on systems that really don't have it.


	-- Dan

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