Re: [git-pull -tip] x86: cpu_debug patches

[Ingo Molnar <mingo@elte.hu>]

* Jaswinder Singh Rajput <jaswinder@kernel.org> wrote:

> We can use cpu_has tests for unknown processors but 'cpu model' is 
> accurate and cover all range.
> 
> cpu_has does not cover following registers:
> 1. platform
> 2. poweron
> 3. control
> 4. bios
> 5. freq
> 6. cache
> 7. misc
> 8. base
> 9. ver
> 10. conf

Firstly these should be added to cpufeatures.h.

Then add cpu_has_xxx() accessors need to be added for them and 
during CPU init they have to be properly set, via two methods:

 - via CPUID (where this is possible+specified in docs)
 - or via "later than CPU version X" checks

Your cpu-model table is equivalent to an explicitly enumerated CPU 
version check, but this breaks every time a new CPU comes out. 

"Later than" or CPUID based feature bits are a lot more future-proof 
- we only have to add support for new _features_ (and quirks, 
occasionally), and dont have to maintain that full table of specific 
models to specific features mapping tables.

	Ingo