You need have a PciHotPlug driver to produce the EFI_PCI_HOT_PLUG_INIT_PROTOCOL
One example: https://github.com/tianocore/edk2/tree/master/OvmfPkg/PciHotPlugInitDxe Laszlo added it. He may provide comment on how to use it. Another example: https://github.com/tianocore/edk2-platforms/tree/devel-MinPlatform/Platform/Intel/KabylakeOpenBoardPkg/Features/PciHotPlug This is to add Thunderbolt support in Kabylake platform. Thank you Yao Jiewen > -----Original Message----- > From: Zhoujian (jay) [mailto:jianjay.z...@huawei.com] > Sent: Friday, December 21, 2018 11:04 AM > To: Yao, Jiewen <jiewen....@intel.com>; edk2-devel@lists.01.org; > ler...@redhat.com > Cc: Huangweidong (C) <weidong.hu...@huawei.com>; liujunjie (A) > <liujunji...@huawei.com>; wangxin (U) <wangxinxin.w...@huawei.com>; > wujing (O) <wujin...@huawei.com>; dengkai (A) <dengk...@huawei.com> > Subject: RE: Question about hotplugging NIC devices to an empty pci-bridge > > I've tried to set PcdPciBusHotplugDeviceSupport to be true in > MdeModulePkg.dec like below: > gEfiMdeModulePkgTokenSpaceGuid.PcdPciBusHotplugDeviceSupport|TRUE > |BOOLEAN|0x0001003d > But the problem still exists. Is there any steps I missed? Or some infos need > to populate to OVMF by Qemu? > > Could you give me more infos? > > Thanks, > Jay Zhou > > > -----Original Message----- > > From: Yao, Jiewen [mailto:jiewen....@intel.com] > > Sent: Thursday, December 20, 2018 8:09 PM > > To: Zhoujian (jay) <jianjay.z...@huawei.com>; edk2-devel@lists.01.org > > Cc: Huangweidong (C) <weidong.hu...@huawei.com>; liujunjie (A) > > <liujunji...@huawei.com>; wangxin (U) > <wangxinxin.w...@huawei.com>; wujing (O) > > <wujin...@huawei.com>; dengkai (A) <dengk...@huawei.com> > > Subject: RE: Question about hotplugging NIC devices to an empty > pci-bridge > > > > Maybe you can use EFI_PCI_HOT_PLUG_INIT_PROTOCOL to reserve some > resource. > > > > See MdePkg\Include\Protocol\PciHotPlugInit.h > > > > Thank you > > Yao Jiewen > > > > > -----Original Message----- > > > From: edk2-devel [mailto:edk2-devel-boun...@lists.01.org] On Behalf > Of > > > Zhoujian (jay) > > > Sent: Thursday, December 20, 2018 7:34 PM > > > To: edk2-devel@lists.01.org > > > Cc: Huangweidong (C) <weidong.hu...@huawei.com>; liujunjie (A) > > > <liujunji...@huawei.com>; wangxin (U) > <wangxinxin.w...@huawei.com>; > > > wujing (O) <wujin...@huawei.com>; dengkai (A) > <dengk...@huawei.com> > > > Subject: [edk2] Question about hotplugging NIC devices to an empty > > > pci-bridge > > > > > > Hi all, > > > > > > The issue occurs when I started a virtual machine in UEFI way by > > > libvirt on qemu-kvm platform, the vm is configured with 8 pci-bridges > > > on root bus0. I hotplug a device like virtual nic to an empty > > > pci-bridge which has no device connected. Login the vm, I can see the > > > device by "lspci"", but it didn't show by "ifconfig -a". Dmesg shows like > > below: > > > pci 0000:04:01.0: BAR 0: no space for [mem size 0x00010000 64bit pref] > > > pci > > > 0000:04:01.0: BAR 0: failed to assign [mem size 0x00010000 64bit pref] > > > pci > > > 0000:04:01.0: BAR 3: no space for [mem size 0x00004000 64bit pref] pci > > > 0000:04:01.0: BAR 3: failed to assign [mem size 0x00004000 64bit pref] > > > > > > Reboot the vm, everything turns back to normal and I can see the new > > > hotplugged nic by "ifconfig -a". > > > > > > Use the OVMF compiling from latest edk2 source code, the same > problem > > > arises. > > > > > > So, my questions are: > > > 1) the generic PCI bus driver in edk2 does not allocate IO and/or MMIO > > > for a bridge if there is no device behind the bridge that consume that > > > kind of resource? > > > 2) What's the purpose of this strategy? > > > 3) Why don't allocate resource to all bridges like seabios? > > > 4) Is there any switch for me to turn off this constraint so that > > > every pci-bridge including empty ones can be assigned IO and memory > window? > > > Otherwise, each time I hotplug a device to empty pci-bridge, a reboot > > > operation should be implemented to use the device? > > > > > > Any help will be appreciated, Thanks! > > > _______________________________________________ > > > edk2-devel mailing list > > > edk2-devel@lists.01.org > > > https://lists.01.org/mailman/listinfo/edk2-devel _______________________________________________ edk2-devel mailing list edk2-devel@lists.01.org https://lists.01.org/mailman/listinfo/edk2-devel
