Re: [RFC] Relaxed PIO read vs. DMA write ordering

[Jesse Barnes]

On Wed, Jan 07, 2004 at 07:02:06PM +0000, Matthew Wilcox wrote:
> So we want a pci_set_relaxed() macro / function() to set this bit
> (otherwise dozens of drivers will start to try to set the bit themselves,
> badly).  If this bit *isn't* set, setting the bit in the transaction will have
> no effect, right?

Right, we'd want that call too.  And actually, if the bit in the command
word isn't set, we're not allowed to set it in individual transactions.

> How about always setting the bit in readb() and having a readb_ordered()
> which doesn't set the bit in the transaction?  That way, drivers which
> call pci_set_relaxed() have the responsibility to verify they're not
> relying on these semantics and use readb_ordered() in any places that
> they are.

Yep, that would work too.

Jesse
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