Re: [edk2-devel] [PATCH 1/1] UefiCpuPkg/MpInitLib: fix apic mode for cpu hotplug

["Ni, Ray" <ray.ni@intel.com>]

Gerd,
I was busy on something else. The patch was ready and I am testing it before sending them out.

Thanks,
Ray


> -----Original Message-----
> From: kraxel@redhat.com <kraxel@redhat.com>
> Sent: Wednesday, May 3, 2023 3:24 PM
> To: Ni, Ray <ray.ni@intel.com>
> Cc: devel@edk2.groups.io; Pawel Polawski <ppolawsk@redhat.com>; Kumar,
> Rahul R <rahul.r.kumar@intel.com>; Oliver Steffen <osteffen@redhat.com>;
> Dong, Eric <eric.dong@intel.com>
> Subject: Re: [edk2-devel] [PATCH 1/1] UefiCpuPkg/MpInitLib: fix apic mode
> for cpu hotplug
> 
> On Tue, Mar 21, 2023 at 07:28:44AM +0000, Ni, Ray wrote:
> > > +  } else if ((PcdGet32 (PcdCpuBootLogicalProcessorNumber) > 0) &&
> > > +             (PcdGet32 (PcdCpuMaxLogicalProcessorNumber) > 255))
> > > +  {
> > > +    X2Apic = TRUE;
> >
> > Gerd,
> > I agree with your needs that want X2 APIC even the actual processor number
> in BIOS phase <= 255.
> >
> > Question: Is it possible that BIOS stays at XAPIC, and later OS switches to X2
> APIC when the maximum CPU count > 255?
> >
> > I am thinking about adding a new PCD to tell MP code switch to x2 apic in the
> first time AP wakes up. Possible timeline for the code change is
> > about within 1 month. Do you think it can meet your needs?
> 
> Ping.  What is the status here?  I'd like to see that fixed for OVMF
> for the next stable release, and freeze is coming closer ...
> 
> take care,
>   Gerd