[rfc] Radeon AGP support patches

[Tijl Coosemans]

On Sun, 26 Oct 2014 12:02:23 -0500 "William A. Mahaffey III" <wam at hiwaay.net>
> *Caution:* idiot question: Is this code for AGP gfx cards ? I thought 
> AGP cards/slots were pretty much dead & buried .... Does this same code 
> get used in/with newer gfx cards/GPU's ? Just askin' .... *Very* nice 
> performance pickup if so. TIA & Thx for the ongoing work :-).

This is for old AGP graphics cards only.  The request to support them
has come up several times on this list and in bug reports.