On Wed, Sep 08, 2021 at 12:06:46PM +0100, Leif Lindholm wrote:
> On Wed, Sep 08, 2021 at 11:01:11 +0200, Gerd Hoffmann wrote:
> > Skip host bridge setup on microvm.
> > 
> > Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3599
> > Signed-off-by: Gerd Hoffmann <[email protected]>
> > Acked-by: Jiewen Yao <[email protected]>
> > ---
> >  OvmfPkg/PlatformPei/MemDetect.c | 4 ++++
> >  1 file changed, 4 insertions(+)
> > 
> > diff --git a/OvmfPkg/PlatformPei/MemDetect.c 
> > b/OvmfPkg/PlatformPei/MemDetect.c
> > index 2c2c4641ec8a..d736b85e0d90 100644
> > --- a/OvmfPkg/PlatformPei/MemDetect.c
> > +++ b/OvmfPkg/PlatformPei/MemDetect.c
> > @@ -135,6 +135,10 @@ QemuUc32BaseInitialization (
> >    UINT32 LowerMemorySize;
> >    UINT32 Uc32Size;
> >  
> > +  if (mHostBridgeDevId == 0xffff /* microvm */) {
> > +    return;
> > +  }
> > +
> 
> This, and the same conditional in the subsequent patch, weirds me out
> a bit. This doesn't tell us we're on microvm, it tells us the device
> ID is invalid.

Well, sort of, yes.  microvm doesn't support pci config space access via
0xcf8, so any attempt to read something there returns 0xff

> Since we know at compile-time that we want to skip this function,
> could we achieve that some other way?

Sure.  Suggestions?  Add a Pcd and set it in Microvm.dsc?
Or is there some better way?

thanks,
  Gerd



-=-=-=-=-=-=-=-=-=-=-=-
Groups.io Links: You receive all messages sent to this group.
View/Reply Online (#80347): https://edk2.groups.io/g/devel/message/80347
Mute This Topic: https://groups.io/mt/85454885/21656
Group Owner: [email protected]
Unsubscribe: https://edk2.groups.io/g/devel/unsub [[email protected]]
-=-=-=-=-=-=-=-=-=-=-=-


Reply via email to