> -----Original Message----- > From: devel@edk2.groups.io <devel@edk2.groups.io> On Behalf Of Ard Biesheuvel > Sent: Friday, April 29, 2022 3:00 PM > To: Gerd Hoffmann <kra...@redhat.com> > Cc: Ni, Ray <ray...@intel.com>; devel@edk2.groups.io; Pawel Polawski > <ppola...@redhat.com>; Ard Biesheuvel > <ardb+tianoc...@kernel.org>; Gao, Liming <gaolim...@byosoft.com.cn>; Wu, Hao > A <hao.a...@intel.com>; Oliver Steffen > <ostef...@redhat.com>; Leif Lindholm <quic_llind...@quicinc.com>; Justen, > Jordan L <jordan.l.jus...@intel.com>; Yao, > Jiewen <jiewen....@intel.com>; Chang, Abner <abner.ch...@hpe.com>; Wang, Jian > J <jian.j.w...@intel.com> > Subject: Re: [edk2-devel] [PATCH v5 1/6] MdeModulePkg/PciHostBridge: io range > is not mandatory > > On Fri, 29 Apr 2022 at 08:50, Gerd Hoffmann <kra...@redhat.com> wrote: > > > > On Wed, Apr 27, 2022 at 03:08:50AM +0000, Ni, Ray wrote: > > > Ard, > > > can you explain more? > > > > > > Your code changes the PciHostBridge driver to ignore the failure of IO > > > allocation. > > > If IO requirement of certain PCI(E) devices can be ignored, can you > > > change the IncompatiblePciDevice protocol > implementation to override the IO request from the devices? > > > > Hmm, it's a problem indeed, device initialization fails in case an > > io bar is present even if the bar is not required to drive the device. > > > > I'd say the risk for regressions is rather low, though, given that it > only affects configurations that would fail PCI resource allocation > today. Or am I missing something? > > In any case, the PCIe spec is clear about this: I/O space is optional, > and we need to incorporate this into the generic code at *some* point. > It makes no sense for every individual platform to keep adding these > hacks. Do you know how Linux handles this? Can Linux allocate resource for PCI(E) devices? How does it deal with the IO type?
> > > Suggestions how to deal with this best? ovmf has it's own > > IncompatiblePciDevice Protocol implementation, so I could > > handle it there because only OvmfPkg/Microvm needs this. > > > > Or should the MdeModulePkg version be updated too? > > > > I'd say we do both, to avoid stalling your series forever :-) Why changing the MdeModulePkg's IncompatiblePciDevice driver can avoid stalling the patch series? I feel it's enough to just change the OvmfPkg version. -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#89389): https://edk2.groups.io/g/devel/message/89389 Mute This Topic: https://groups.io/mt/90623478/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-
