PMR enabling set by pre-boot DMA protection is cleared by RC
when boot guard is enabled. Pre-boot DMA protection should only
reset VT-d BAR when it is 0 and reset PMR region when it is
not programmed to protect all memory address.
PlatformVTdInfoSamplePei driver installs the null root entry table ppi.
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

Cc: Ray Ni <ray.ni@intel.com>
Cc: Rangasai V Chaganty <rangasai.v.chaganty@intel.com>

Sheng Wei (2):
  PlatformVTdInfoSamplePei: Install Null Root Entry Table PPI
  IntelVTdPmrPei: Fix PMR enabling setting confilct

 .../Feature/VTd/IntelVTdPmrPei/IntelVTdPmrPei.c    | 14 ++++++
 .../Feature/VTd/IntelVTdPmrPei/IntelVTdPmrPei.h    | 15 +++++++
 .../Feature/VTd/IntelVTdPmrPei/VtdReg.c            | 50 ++++++++++++++++++++++
 .../PlatformVTdInfoSamplePei.c                     | 16 +++++++
 4 files changed, 95 insertions(+)

-- 
2.16.2.windows.1


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