From de103f1981cfca90dd19296d4b20449a2b93dc26 Mon Sep 17 00:00:00 2001 From: Foster Nong Date: Thu, 29 Sep 2022 17:20:01 +0800 Subject: [PATCH] MdeModulePkg: Handle InitialVFs=0 case for SR-IOV Per the section 3.3.5 SR-IOV spec v1.1, InitialVFs (0ch). InitialVFs indicates to SR-PCIM the number of VFs that are initially associated with the PF. The minimum value of InitialVFs is 0. Below code is used to calculate SR-IOV reserved bus number, if InitialVFs =0, it maybe calculate the wrong bus number in this case. LastVF = PFRid + FirstVFOffset + (PciIoDevice->InitialVFs - 1) * VFStride we can fix it with below code: if (PciIoDevice->InitialVFs == 0) { PciIoDevice->ReservedBusNum = 0; } else { PFRid = EFI_PCI_RID (Bus, Device, Func); LastVF = PFRid + FirstVFOffset + (PciIoDevice->InitialVFs - 1) * VFStride; // // Calculate ReservedBusNum for this PF // PciIoDevice->ReservedBusNum = (UINT16)(EFI_PCI_BUS_OF_RID (LastVF) - Bus + 1); // // Calculate ReservedBusNum for this PF // PciIoDevice->ReservedBusNum = (UINT16)(EFI_PCI_BUS_OF_RID (LastVF) - Bus + 1); } https://bugzilla.tianocore.org/show_bug.cgi?id=4069 Signed-off-by: Foster Nong Reviewed-by: Ray Ni --- .../Bus/Pci/PciBusDxe/PciEnumeratorSupport.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciEnumeratorSupport.c b/MdeModulePkg/Bus/Pci/PciBusDxe/PciEnumeratorSupport.c index 509f828b62..eb250f6f7b 100644 --- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciEnumeratorSupport.c +++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciEnumeratorSupport.c @@ -2416,13 +2416,17 @@ CreatePciIoDevice ( // // Calculate LastVF // - PFRid = EFI_PCI_RID (Bus, Device, Func); - LastVF = PFRid + FirstVFOffset + (PciIoDevice->InitialVFs - 1) * VFStride; + if (PciIoDevice->InitialVFs == 0) { + PciIoDevice->ReservedBusNum = 0; + } else { + PFRid = EFI_PCI_RID (Bus, Device, Func); + LastVF = PFRid + FirstVFOffset + (PciIoDevice->InitialVFs - 1) * VFStride; - // - // Calculate ReservedBusNum for this PF - // - PciIoDevice->ReservedBusNum = (UINT16)(EFI_PCI_BUS_OF_RID (LastVF) - Bus + 1); + // + // Calculate ReservedBusNum for this PF + // + PciIoDevice->ReservedBusNum = (UINT16)(EFI_PCI_BUS_OF_RID (LastVF) - Bus + 1); + } DEBUG (( DEBUG_INFO,