Re: RFC: outb 0x80 in inb_p, outb_p harmful on some modern AMD64 with MCP51 laptops

["H. Peter Anvin" <hpa@zytor.com>]

David Newall wrote:
> Exactly.  You think it's 2us, but the documentation doesn't say.  The _p 
> functions are generic inasmuch as they provide an unspecified delay.  
> Drivers which work across platforms, and which use _p, therefore have 
> different delays on different platforms.  Should the length of the delay 
> be unimportant?  I wouldn't have thought so.  If it is important, does 
> that mean that such drivers are buggy on some platforms?

That the _p delay is different across platforms is actually to be 
expected, since it pretty much amounts to a platform delay.  And yes, if 
it is used as a specific walltime delay that has nothing to do with the 
bus architecture of the system then I would classify that as a driver bug.

	-hpa
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