Re: [PATCH v2] IntelSiliconPkg/IntelVTdDxe: Support Multi PCI Root Bus

["Ni, Ray" <ray.ni@intel.com>]

Can you rely on the PciRootBridgeIo protocol instances instead of this library?

It will make the driver usable in platforms that don't produce the PciHostBridgeLib.

Thanks,
Rya

> -----Original Message-----
> From: Sheng, W <w.sheng@intel.com>
> Sent: Monday, October 18, 2021 4:43 PM
> To: devel@edk2.groups.io
> Cc: Kowalewski, Robert <robert.kowalewski@intel.com>; Huang, Jenny <jenny.huang@intel.com>; Ni, Ray <ray.ni@intel.com>;
> Chaganty, Rangasai V <rangasai.v.chaganty@intel.com>; Albecki, Mateusz <mateusz.albecki@intel.com>
> Subject: [PATCH v2] IntelSiliconPkg/IntelVTdDxe: Support Multi PCI Root Bus
> 
> Some system may has multi PCI root bus. It needs to use function
>  PciHostBridgeGetRootBridges () to get the root bus count. Then,
>  scan each root bus to get all devices.
> 
> REF: https://bugzilla.tianocore.org/show_bug.cgi?id=3695
> 
> Signed-off-by: Robert Kowalewski <robert.kowalewski@intel.com>
> Signed-off-by: Sheng Wei <w.sheng@intel.com>
> Cc: Jenny Huang <jenny.huang@intel.com>
> Cc: Ray Ni <ray.ni@intel.com>
> Cc: Rangasai V Chaganty <rangasai.v.chaganty@intel.com>
> Cc: Robert Kowalewski <robert.kowalewski@intel.com>
> Cc: Albecki Mateusz <mateusz.albecki@intel.com>
> ---
>  .../Feature/VTd/IntelVTdDxe/DmaProtection.h             |  1 +
>  .../Feature/VTd/IntelVTdDxe/DmarAcpiTable.c             | 17 ++++++++++++++---
>  .../Feature/VTd/IntelVTdDxe/IntelVTdDxe.inf             |  1 +
>  3 files changed, 16 insertions(+), 3 deletions(-)
> 
> diff --git a/Silicon/Intel/IntelSiliconPkg/Feature/VTd/IntelVTdDxe/DmaProtection.h
> b/Silicon/Intel/IntelSiliconPkg/Feature/VTd/IntelVTdDxe/DmaProtection.h
> index a24fbc37..97061de5 100644
> --- a/Silicon/Intel/IntelSiliconPkg/Feature/VTd/IntelVTdDxe/DmaProtection.h
> +++ b/Silicon/Intel/IntelSiliconPkg/Feature/VTd/IntelVTdDxe/DmaProtection.h
> @@ -23,6 +23,7 @@
>  #include <Library/PerformanceLib.h>
>  #include <Library/PrintLib.h>
>  #include <Library/ReportStatusCodeLib.h>
> +#include <Library/PciHostBridgeLib.h>
> 
>  #include <Guid/EventGroup.h>
>  #include <Guid/Acpi.h>
> diff --git a/Silicon/Intel/IntelSiliconPkg/Feature/VTd/IntelVTdDxe/DmarAcpiTable.c
> b/Silicon/Intel/IntelSiliconPkg/Feature/VTd/IntelVTdDxe/DmarAcpiTable.c
> index 2d9b4374..e717aeb2 100644
> --- a/Silicon/Intel/IntelSiliconPkg/Feature/VTd/IntelVTdDxe/DmarAcpiTable.c
> +++ b/Silicon/Intel/IntelSiliconPkg/Feature/VTd/IntelVTdDxe/DmarAcpiTable.c
> @@ -682,6 +682,9 @@ ProcessDhrd (
>    UINT8                                             SecondaryBusNumber;
>    EFI_STATUS                                        Status;
>    VTD_SOURCE_ID                                     SourceId;
> +  PCI_ROOT_BRIDGE                                   *RootBridges;
> +  UINTN                                             RootBridgeCount;
> +  UINTN                                             Index;
> 
>    mVtdUnitInformation[VtdIndex].VtdUnitBaseAddress = (UINTN)DmarDrhd->RegisterBaseAddress;
>    DEBUG ((DEBUG_INFO,"  VTD (%d) BaseAddress -  0x%016lx\n", VtdIndex, DmarDrhd->RegisterBaseAddress));
> @@ -692,9 +695,17 @@ ProcessDhrd (
>      mVtdUnitInformation[VtdIndex].PciDeviceInfo.IncludeAllFlag = TRUE;
>      DEBUG ((DEBUG_INFO,"  ProcessDhrd: with INCLUDE ALL\n"));
> 
> -    Status = ScanPciBus((VOID *)VtdIndex, DmarDrhd->SegmentNumber, 0, ScanBusCallbackRegisterPciDevice);
> -    if (EFI_ERROR (Status)) {
> -      return Status;
> +    RootBridges = PciHostBridgeGetRootBridges (&RootBridgeCount);
> +    if ((RootBridges == NULL) || (RootBridgeCount == 0)) {
> +      return EFI_UNSUPPORTED;
> +    }
> +    DEBUG ((DEBUG_INFO,"Find %d root bridges\n", RootBridgeCount));
> +    for (Index = 0; Index < RootBridgeCount; Index++) {
> +      DEBUG ((DEBUG_INFO,"Scan root bridges : %d, Segment : %d, Bus : 0x%02X\n", Index, RootBridges[Index].Segment,
> RootBridges[Index].Bus.Base));
> +      Status = ScanPciBus((VOID *)VtdIndex, (UINT16) RootBridges[Index].Segment, (UINT8) RootBridges[Index].Bus.Base,
> ScanBusCallbackRegisterPciDevice);
> +      if (EFI_ERROR (Status)) {
> +        return Status;
> +      }
>      }
>    } else {
>      mVtdUnitInformation[VtdIndex].PciDeviceInfo.IncludeAllFlag = FALSE;
> diff --git a/Silicon/Intel/IntelSiliconPkg/Feature/VTd/IntelVTdDxe/IntelVTdDxe.inf
> b/Silicon/Intel/IntelSiliconPkg/Feature/VTd/IntelVTdDxe/IntelVTdDxe.inf
> index 220636ad..25ff86f4 100644
> --- a/Silicon/Intel/IntelSiliconPkg/Feature/VTd/IntelVTdDxe/IntelVTdDxe.inf
> +++ b/Silicon/Intel/IntelSiliconPkg/Feature/VTd/IntelVTdDxe/IntelVTdDxe.inf
> @@ -55,6 +55,7 @@
>    PerformanceLib
>    PrintLib
>    ReportStatusCodeLib
> +  PciHostBridgeLib
> 
>  [Guids]
>    gEfiEventExitBootServicesGuid   ## CONSUMES ## Event
> --
> 2.16.2.windows.1