VS2008 seems to think that the "PciExBarBase" variable (introduced in commit 7b8fe63561b4) can be evaluated for the AddReservedMemoryBaseSizeHob() function call with its value being uninitialized / indeterminate. This is not the case (see "mHostBridgeDevId"); suppress the warning.
Reported-by: David Woodhouse <[email protected]> Ref: http://thread.gmane.org/gmane.comp.bios.edk2.devel/8871/focus=9431 Cc: David Woodhouse <[email protected]> Cc: Jordan Justen <[email protected]> Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Laszlo Ersek <[email protected]> --- Notes: - Public branch: https://github.com/lersek/edk2/commits/suppress_vs2008 - Patch formatted with --function-context for easier review OvmfPkg/PlatformPei/Platform.c | 1 + 1 file changed, 1 insertion(+) diff --git a/OvmfPkg/PlatformPei/Platform.c b/OvmfPkg/PlatformPei/Platform.c index 0fc227803a84..509343e0bee5 100644 --- a/OvmfPkg/PlatformPei/Platform.c +++ b/OvmfPkg/PlatformPei/Platform.c @@ -184,99 +184,100 @@ VOID MemMapInitialization ( VOID ) { // // Create Memory Type Information HOB // BuildGuidDataHob ( &gEfiMemoryTypeInformationGuid, mDefaultMemoryTypeInformation, sizeof(mDefaultMemoryTypeInformation) ); // // Add PCI IO Port space available for PCI resource allocations. // BuildResourceDescriptorHob ( EFI_RESOURCE_IO, EFI_RESOURCE_ATTRIBUTE_PRESENT | EFI_RESOURCE_ATTRIBUTE_INITIALIZED, PcdGet64 (PcdPciIoBase), PcdGet64 (PcdPciIoSize) ); // // Video memory + Legacy BIOS region // AddIoMemoryRangeHob (0x0A0000, BASE_1MB); if (!mXen) { UINT32 TopOfLowRam; UINT64 PciExBarBase; UINT32 PciBase; UINT32 PciSize; TopOfLowRam = GetSystemMemorySizeBelow4gb (); + PciExBarBase = 0; if (mHostBridgeDevId == INTEL_Q35_MCH_DEVICE_ID) { // // The MMCONFIG area is expected to fall between the top of low RAM and // the base of the 32-bit PCI host aperture. // PciExBarBase = FixedPcdGet64 (PcdPciExpressBaseAddress); ASSERT (TopOfLowRam <= PciExBarBase); ASSERT (PciExBarBase <= MAX_UINT32 - SIZE_256MB); PciBase = (UINT32)(PciExBarBase + SIZE_256MB); } else { PciBase = (TopOfLowRam < BASE_2GB) ? BASE_2GB : TopOfLowRam; } // // address purpose size // ------------ -------- ------------------------- // max(top, 2g) PCI MMIO 0xFC000000 - max(top, 2g) // 0xFC000000 gap 44 MB // 0xFEC00000 IO-APIC 4 KB // 0xFEC01000 gap 1020 KB // 0xFED00000 HPET 1 KB // 0xFED00400 gap 111 KB // 0xFED1C000 gap (PIIX4) / RCRB (ICH9) 16 KB // 0xFED20000 gap 896 KB // 0xFEE00000 LAPIC 1 MB // PciSize = 0xFC000000 - PciBase; AddIoMemoryBaseSizeHob (PciBase, PciSize); PcdSet64 (PcdPciMmio32Base, PciBase); PcdSet64 (PcdPciMmio32Size, PciSize); AddIoMemoryBaseSizeHob (0xFEC00000, SIZE_4KB); AddIoMemoryBaseSizeHob (0xFED00000, SIZE_1KB); if (mHostBridgeDevId == INTEL_Q35_MCH_DEVICE_ID) { AddIoMemoryBaseSizeHob (ICH9_ROOT_COMPLEX_BASE, SIZE_16KB); // // Note: there should be an // // AddIoMemoryBaseSizeHob (PciExBarBase, SIZE_256MB); // // call below, just like the one above for RCBA. However, Linux insists // that the MMCONFIG area be marked in the E820 or UEFI memory map as // "reserved memory" -- Linux does not content itself with a simple gap // in the memory map wherever the MCFG ACPI table points to. // // This appears to be a safety measure. The PCI Firmware Specification // (rev 3.1) says in 4.1.2. "MCFG Table Description": "The resources can // *optionally* be returned in [...] EFIGetMemoryMap as reserved memory // [...]". (Emphasis added here.) // // Normally we add memory resource descriptor HOBs in // QemuInitializeRam(), and pre-allocate from those with memory // allocation HOBs in InitializeRamRegions(). However, the MMCONFIG area // is most definitely not RAM; so, as an exception, cover it with // uncacheable reserved memory right here. // AddReservedMemoryBaseSizeHob (PciExBarBase, SIZE_256MB, FALSE); BuildMemoryAllocationHob (PciExBarBase, SIZE_256MB, EfiReservedMemoryType); } AddIoMemoryBaseSizeHob (PcdGet32(PcdCpuLocalApicBaseAddress), SIZE_1MB); } } -- 1.8.3.1 _______________________________________________ edk2-devel mailing list [email protected] https://lists.01.org/mailman/listinfo/edk2-devel
