Re: [RFC PATCH v2] tools/x86: add kcpuid tool to show raw CPU features

[Feng Tang]

On Fri, Sep 25, 2020 at 07:24:37PM +0200, Borislav Petkov wrote:
> On Tue, Sep 22, 2020 at 01:27:50PM +0800, Feng Tang wrote:
> > +++ b/tools/arch/x86/kcpuid/cpuid.txt
> > @@ -0,0 +1,58 @@
> > +# Leaf 00H
> > +
> > +LEAF[00000000],SUBLEAF[00],EAX[ 31:0],max_basic_leafs, Max input value for supported subleafs
> > +
> > +
> > +# Leaf 01H
> > +
> > +LEAF[00000001],SUBLEAF[00],EAX[  3:0],stepping, Stepping ID
> > +LEAF[00000001],SUBLEAF[00],EAX[  7:4],model, Model
> > +LEAF[00000001],SUBLEAF[00],EAX[ 11:8],family, Family ID
> > +LEAF[00000001],SUBLEAF[00],EAX[13:12],processor, Processor Type
> > +LEAF[00000001],SUBLEAF[00],EAX[19:16],model_ext, Extended Model ID
> > +LEAF[00000001],SUBLEAF[00],EAX[27:20],family_ext, Extended Family ID
> 
> Yeah, this looks good but how about we simplify and ease the parsing
> even more? I.e., make it a real csv:
> 
> # Table row names:
> # LEAF,SUBLEAF,register_name,bits,short name, long name
> 
> 0x1,0,EBX,7:0,brand,Brand Index
> 0x1,0,EBX,15:8,clflush_size,CLFLUSH line size (value * 8) in bytes
> 0x1,0,EBX,23:16,max_cpu_id,Maxim number of addressable logic cpu ID in this package
> ...
> 
> Yeah, this way it might not be as readable but the format is pretty simple and
> everybody knows .csv so....
> 
> We can even do vertical alignment for better readability:
> 
> #     LEAF,SUBLEAF,register,  bits,short name, long name
>          1,	 0,	EBX,   7:0,brand,Brand Index
>          1,	 0,	EBX,  15:8,clflush_size,CLFLUSH line size (value * 8) in bytes
>      	 1,	 0,	EBX, 23:16,max_cpu_id,Maxim number of addressable logic cpu ID in this package
> 0x80000000,	12,	EAX,     3,eee, EEE
> 
> and can keep it in tabellary form this way. The parsing code should
> asimply split on ',' and ignore whitespace.
> 
> Thoughts?
 
Thanks, it looks good to me. One thing is in v2 we supported ',' in the
long name field, but that's minor as we could avoid using it in .csv 

- Feng

> -- 
> Regards/Gruss,
>     Boris.
> 
> https://people.kernel.org/tglx/notes-about-netiquette