RE: [PATCH v3 1/9] drivers: base: Add hardware prefetch control core driver

["tarumizu.kohei@fujitsu.com" <tarumizu.kohei@fujitsu.com>]

Thanks for the comment.

> This is A64FX specific.
> This is x86 specific.
> This is A64FX specific.
> 
> So why is this in generic code and why needs x86 to populate the A64FX bits and
> make them invisible? Same the other way round.

As you commented, current generic code includes things that are not
needed outside of specific hardware.
 
> Now imagine a few other [sub]architectures come around and add their specific
> prefetcher control knobs, strings and whatever. That's going to be unmaintainable
> in no time.
> 
> This is not comparable to the cache attributes where the architectures share a
> significant amount of subsets. You just demonstrated that X86 and A64FX share
> not even a single entry.
> 
> The core code should provide infrastructure to manage the [sub]architecture
> specific control files at different cache levels.
> 
> Not more not less.

I understand the risks of the current implementation.

I would like to fix the core code to provide infrastructure to manage
the [sub]architecture specific control files at different cache levels
by also referring to the comments I received at patch 7/9.