Re: [RFC] Cachemap for 2.6.12rc4-mm1. Was Re: [PATCH] enhance x86 MTRR handling

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

Dave Jones wrote:
>  > 
>  > Drop the vendor check; PAT is a generic x86 feature.  If AMD is not 
>  > compatible (see below), then use X86_VENDOR_AMD: and default:.
> 
> Done. Does transmeta have PAT btw ? I know newer VIA has it,
> but I haven't looked through the docs to double check its
> implementation yet.
> 

The Efficeon (TM8xxx) series does have PAT.
> 
>  > >+ * Note: On Athlon cpus PAT2/PAT3 & PAT6/PAT7 are both Uncacheable since 
>  > >+ *	 there is no uncached type.
>  > If one sets the PAT to "uncached", does one get the same function as 
>  > "uncachable"?
> 
> AIUI, only as long as we don't have an MTRR covering the same range marked WC.
> It seems to be the only thing I could find documenting the differences
> between 'uncached' and 'uncacheable' in this context.
> Though I've only looked through the Intel & AMD K8 docs, I don't have
> the K7 ones to hand.
> 

I mean, on the Athlon series, is it really necessary to use a different 
value?

	-hpa