On Wed, 11 Sep 2019 19:30:46 +0200 "Laszlo Ersek" <ler...@redhat.com> wrote:
> On 09/10/19 17:58, Igor Mammedov wrote: > > On Mon, 9 Sep 2019 21:15:44 +0200 > > Laszlo Ersek <ler...@redhat.com> wrote: > > [...] > > > It looks like fwcfg smi feature negotiation isn't reusable in this case. > > I'd prefer not to add another device just for another SMI feature > > negotiation/activation. > > I thought it could be a register on the new CPU hotplug controller that > we're going to need anyway (if I understand correctly, at least). If we don't have to 'park' hotplugged CPUs, then I don't see a need for an extra controller. > But: > > > How about stealing reserved register from pci-host similar to your > > extended TSEG commit (2f295167 q35/mch: implement extended TSEG sizes)? > > (Looking into spec can (ab)use 0x58 or 0x59 register) > > Yes, that should work. > > In fact, I had considered 0x58 / 0x59 when looking for unused registers > for extended TSEG configuration: > > http://mid.mail-archive.com/d8802612-0b11-776f-b209-53bbdaf67515@redhat.com > > So I'm OK with this, thank you. Thanks for the tip! ... patches with a stolen register are on the way to mail-list.