From 8be3ff8fb82026b6294b1e203563737bfae76a57 Mon Sep 17 00:00:00 2001
From: Jiewen Yao <jiewen.yao@intel.com>
Date: Thu, 21 Sep 2017 15:06:46 +0800
Subject: [PATCH] IntelSiliconPkg/dec: Clarify VTdPolicy.

Clarify the VTdPolicy is for both PEI and DXE.

Cc: Star Zeng <star.zeng@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jiewen Yao <jiewen.yao@intel.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
---
 IntelSiliconPkg/IntelSiliconPkg.dec | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/IntelSiliconPkg/IntelSiliconPkg.dec b/IntelSiliconPkg/IntelSiliconPkg.dec
index 941380a084..b88630d138 100644
--- a/IntelSiliconPkg/IntelSiliconPkg.dec
+++ b/IntelSiliconPkg/IntelSiliconPkg.dec
@@ -48,8 +48,8 @@
   gIntelSiliconPkgTokenSpaceGuid.PcdIntelGraphicsVbtFileGuid|{ 0xa9, 0x2d, 0x75, 0x56, 0x6b, 0xde, 0x95, 0x48, 0x88, 0x19, 0x19, 0x45, 0xb6, 0xb7, 0x6c, 0x22 }|VOID*|0x00000001
 
   ## The mask is used to control VTd behavior.<BR><BR>
-  #  BIT0: Enable IOMMU during boot.
-  #  BIT1: Enable IOMMU on exit boot service.
+  #  BIT0: Enable IOMMU during boot (If DMAR table is installed in DXE. If VTD_INFO_PPI is installed in PEI.)
+  #  BIT1: Enable IOMMU when transfer control to OS (ExitBootService in normal boot. EndOfPEI in S3)
   # @Prompt The policy for VTd driver behavior.
   gIntelSiliconPkgTokenSpaceGuid.PcdVTdPolicyPropertyMask|1|UINT8|0x00000002