From: Andi Kleen <ak@suse.de>
To: "Bryan O'Sullivan" <bos@pathscale.com>
Subject: Re: [PATCH 2 of 2] __raw_memcpy_toio32 for x86_64
Date: Thu, 12 Jan 2006 02:33:51 +0100
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On Thursday 12 January 2006 02:27, Bryan O'Sullivan wrote:

> > > +__raw_memcpy_toio32:
> > > +	movl %edx,%ecx
> > > +	shrl $1,%ecx
> > 
> > 1? If it's called memcpy it should get a byte argument, no? If not
> > name it something else, otherwise everybody will be confused. 
> 
> It's called toio32 for a reason :-)
> 
> Also, the kernel doc clearly states its purpose.

I think it's deeply wrong to reuse names of standard functions with different
arguments. Either pass bytes or give it some other name.
 
> > movsq? I thought you wanted 32bit IO? 
> 
> The northbridge will split qword writes into pairs of dword writes.

That sounds like a very chipset specific assumption. Is that safe
to make? If yes you would need to document it clearly. But most likely
it's not a good idea to do this. Even if it works right now it would
be another death trap for the next user.

-Andi
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