Re: [PATCH v7 08/16] i386: Expose module level in CPUID[0x1F]

[Zhao Liu]

On Mon, Jan 15, 2024 at 02:57:30PM +0800, Yuan Yao wrote:
> Date: Mon, 15 Jan 2024 14:57:30 +0800
> From: Yuan Yao <yuan.yao@linux.intel.com>
> Subject: Re: [PATCH v7 08/16] i386: Expose module level in CPUID[0x1F]
> 
> On Mon, Jan 15, 2024 at 02:20:20PM +0800, Zhao Liu wrote:
> > On Mon, Jan 15, 2024 at 01:20:22PM +0800, Yuan Yao wrote:
> > > Date: Mon, 15 Jan 2024 13:20:22 +0800
> > > From: Yuan Yao <yuan.yao@linux.intel.com>
> > > Subject: Re: [PATCH v7 08/16] i386: Expose module level in CPUID[0x1F]
> > >
> > > Ah, so my understanding is incorrect on this.
> > >
> > > I tried on one raptor lake i5-i335U, which also hybrid soc but doesn't 
> > > have
> > > module level, in this case 0x1f and 0xb have same values in core/lp level.
> >
> > Some socs have modules/dies but they don't expose them in 0x1f.
> 
> Here they don't expose because from hardware level they can't or possible
> software level configuration (i.e. disable some cores in bios) ?
>

This leaf is decided at hardware level. Whether or not which levels are exposed
sometimes depends if there is the topology-related feature, but there is no 
clear
rule (just as in the ADL family neither ADL-S/P exposes modules, while ADL-N
exposes modules).

Regards,
Zhao