This patch is to check the PCI Memory Base Address Register is valid or not.

*** a\NetworkPkg\SnpDxe\Snp.c 2019-11-11 16:53:40.773300500 +0530

--- b\NetworkPkg\SnpDxe\Snp.c 2019-11-03 18:46:02.000000000 +0530

*************** SimpleNetworkDriverStart (

*** 266,272 ****

UINT8 BarIndex;

PXE_STATFLAGS InitStatFlags;

EFI_PCI_IO_PROTOCOL *PciIo;

! EFI_ACPI_QWORD_ADDRESS_SPACE_DESCRIPTOR *BarDesc = NULL;

BOOLEAN FoundIoBar;

BOOLEAN FoundMemoryBar;

--- 266,272 ----

UINT8 BarIndex;

PXE_STATFLAGS InitStatFlags;

EFI_PCI_IO_PROTOCOL *PciIo;

! EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR *BarDesc;

BOOLEAN FoundIoBar;

BOOLEAN FoundMemoryBar;

*************** SimpleNetworkDriverStart (

*** 481,494 ****

} else if (EFI_ERROR (Status)) {

goto Error_DeleteSNP;

}

! //PXE boot fails with cards having non-continuous BAR.

! // From UEFI Spec, GetBarAttributes can have only descriptors of type ACPI_QWORD_ADDRESS_SPACE_DESCRIPTOR

! // and ACPI_END_TAG_DESCRIPTOR.

! if( BarDesc->Header.Header.Byte != ACPI_QWORD_ADDRESS_SPACE_DESCRIPTOR ) {

! FreePool (BarDesc);

! continue;

! }

if ((!FoundMemoryBar) && (BarDesc->ResType == ACPI_ADDRESS_SPACE_TYPE_MEM)) {

Snp->MemoryBarIndex = BarIndex;

FoundMemoryBar = TRUE;

--- 481,487 ----

} else if (EFI_ERROR (Status)) {

goto Error_DeleteSNP;

}

if ((!FoundMemoryBar) && (BarDesc->ResType == ACPI_ADDRESS_SPACE_TYPE_MEM)) {

Snp->MemoryBarIndex = BarIndex;

FoundMemoryBar = TRUE;