Re: [PATCH v3 3/3] IntelSiliconPkg/PlatformVTdInfoSamplePei: Install Null Root Entry Table

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

Reviewed-by: Ray Ni <ray.ni@intel.com>

> -----Original Message-----
> From: Sheng, W <w.sheng@intel.com>
> Sent: Monday, August 31, 2020 2:38 PM
> To: devel@edk2.groups.io
> Cc: Ni, Ray <ray.ni@intel.com>; Chaganty, Rangasai V <rangasai.v.chaganty@intel.com>
> Subject: [PATCH v3 3/3] IntelSiliconPkg/PlatformVTdInfoSamplePei: Install Null Root Entry Table
> 
> BIOS uses TE with a null root entry table to block VT-d engine access
> to block any DMA traffic in pre-memory phase.
> 
> REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2867
> 
> Change-Id: I6c086c1f26e60f781de79cc37677cc5717c5edec
> Cc: Ray Ni <ray.ni@intel.com>
> Cc: Rangasai V Chaganty <rangasai.v.chaganty@intel.com>
> Signed-off-by: Sheng Wei <w.sheng@intel.com>
> ---
>  .../PlatformVTdInfoSamplePei/PlatformVTdInfoSamplePei.c  | 16 ++++++++++++++++
>  .../PlatformVTdInfoSamplePei.inf                         |  3 ++-
>  2 files changed, 18 insertions(+), 1 deletion(-)
> 
> diff --git a/Silicon/Intel/IntelSiliconPkg/Feature/VTd/PlatformVTdInfoSamplePei/PlatformVTdInfoSamplePei.c
> b/Silicon/Intel/IntelSiliconPkg/Feature/VTd/PlatformVTdInfoSamplePei/PlatformVTdInfoSamplePei.c
> index 6f6c14f7..616a96ce 100644
> --- a/Silicon/Intel/IntelSiliconPkg/Feature/VTd/PlatformVTdInfoSamplePei/PlatformVTdInfoSamplePei.c
> +++ b/Silicon/Intel/IntelSiliconPkg/Feature/VTd/PlatformVTdInfoSamplePei/PlatformVTdInfoSamplePei.c
> @@ -9,6 +9,7 @@
>  #include <PiPei.h>
> 
>  #include <Ppi/VtdInfo.h>
> +#include <Ppi/VtdNullRootEntryTable.h>
> 
>  #include <Library/PeiServicesLib.h>
>  #include <Library/DebugLib.h>
> @@ -164,6 +165,15 @@ EFI_PEI_PPI_DESCRIPTOR mPlatformVTdNoIgdInfoSampleDesc = {
>    &mPlatformVTdNoIgdSample
>  };
> 
> +// BIOS uses TE with a null root entry table to block VT-d engine access to block any DMA traffic in pre-memory phase.
> +EDKII_VTD_NULL_ROOT_ENTRY_TABLE_PPI mNullRootEntryTable = 0xFED20000;
> +
> +EFI_PEI_PPI_DESCRIPTOR mPlatformNullRootEntryTableDesc = {
> +  (EFI_PEI_PPI_DESCRIPTOR_PPI | EFI_PEI_PPI_DESCRIPTOR_TERMINATE_LIST),
> +  &gEdkiiVTdNullRootEntryTableGuid,
> +  &mNullRootEntryTable
> +};
> +
>  /**
>    Initialize VTd register.
>    Initialize the VTd hardware unit which has INCLUDE_PCI_ALL set
> @@ -344,6 +354,12 @@ PlatformVTdInfoSampleInitialize (
>    if (!EFI_ERROR(Status)) {
>      SiliconInitialized = TRUE;
>    }
> +
> +  Status = PeiServicesInstallPpi (&mPlatformNullRootEntryTableDesc);
> +  if (EFI_ERROR (Status)) {
> +    ASSERT_EFI_ERROR (Status);
> +  }
> +
>    DEBUG ((DEBUG_INFO, "SiliconInitialized - %x\n", SiliconInitialized));
>    if (!SiliconInitialized) {
>      Status = PeiServicesNotifyPpi (&mSiliconInitializedNotifyList);
> diff --git a/Silicon/Intel/IntelSiliconPkg/Feature/VTd/PlatformVTdInfoSamplePei/PlatformVTdInfoSamplePei.inf
> b/Silicon/Intel/IntelSiliconPkg/Feature/VTd/PlatformVTdInfoSamplePei/PlatformVTdInfoSamplePei.inf
> index dacfdf5e..b35853b6 100644
> --- a/Silicon/Intel/IntelSiliconPkg/Feature/VTd/PlatformVTdInfoSamplePei/PlatformVTdInfoSamplePei.inf
> +++ b/Silicon/Intel/IntelSiliconPkg/Feature/VTd/PlatformVTdInfoSamplePei/PlatformVTdInfoSamplePei.inf
> @@ -38,7 +38,8 @@
>    IoLib
> 
>  [Ppis]
> -  gEdkiiVTdInfoPpiGuid         ## PRODUCES
> +  gEdkiiVTdInfoPpiGuid              ## PRODUCES
> +  gEdkiiVTdNullRootEntryTableGuid   ## PRODUCES
> 
>  [Depex]
>    gEfiPeiMasterBootModePpiGuid
> --
> 2.16.2.windows.1