Good suggestion, Gerd. I agree with both suggestion. We should rename XenTimerDxe to LocalApicTimerDxe.
> -----Original Message----- > From: Xu, Min M <min.m...@intel.com> > Sent: Thursday, October 14, 2021 1:20 PM > To: devel@edk2.groups.io; kra...@redhat.com > Cc: Ard Biesheuvel <ardb+tianoc...@kernel.org>; Justen, Jordan L > <jordan.l.jus...@intel.com>; Brijesh Singh <brijesh.si...@amd.com>; Erdem > Aktas <erdemak...@google.com>; James Bottomley <j...@linux.ibm.com>; > Yao, Jiewen <jiewen....@intel.com>; Tom Lendacky > <thomas.lenda...@amd.com> > Subject: RE: [edk2-devel] [PATCH V2 28/28] OvmfPkg: Add LocalApicTimerDxe > > On October 12, 2021 9:02 PM, Gerd Hoffmann wrote: > > On Tue, Oct 05, 2021 at 11:39:39AM +0800, Min Xu wrote: > > > RFC： https://bugzilla.tianocore.org/show_bug.cgi?id=3429 > > > > > > TDX guest supports LocalApicTimer. But in current OvmfPkg the > > > supported timer is 8254TimerDxe. So > > > gUefiOvmfPkgTokenSpaceGuid.PcdTimerSelector > > > is introduced to select the running Timer. The Timer driver will check > > > the TimerSelector in its entry point. The default Timer is 8254. > > > > Hmm. > > > > We already have a local apic timer implementation (XenTimerDxe). Works fine > > with kvm, microvm already uses that. See commit 76602f45dcd9 > > ("OvmfPkg/Microvm: use XenTimerDxe (lapic timer)"). > > > > So, first I'd suggest to just use that (maybe rename the thing to avoid > confusion > > as it isn't really Xen specific). > Thanks for reminder. Let me first do some more investigation about the > XenTimerDxe. It will be better to use an existing lapic timer than > introducing a > new one. > > > > Next question is whenever there is a need for a runtime switch. I doubt it > > is > > possible to create a virtual machine without lapic, so switching ovmf from > 8254 > > (aka pit) to lapic unconditionally should work fine. > > Quick smoke test (patch below) shows no obvious problems. > Let me do some more investigation. > > > > Thanks. > Min -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#82071): https://edk2.groups.io/g/devel/message/82071 Mute This Topic: https://groups.io/mt/86085771/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-
