[patch] MdeModulePkg/Ufs: ensure the DBC field of UTP PRDT is dword-aligned

[Feng Tian <feng.tian@intel.com>]

According to UFS Host Controller Spec(JESD223), the bits 1:0 of this
DataByteCount field shall be 11b to indicate Dword granularity.

But the size of UFS Request Sense Data Response defined in UFS Spec
(JESD220C) is 18 which is not Dword aligned, we would have to round
down to the multiple of 4 to fill the DBC field to avoid bring issue
on some UFS HCs.

Cc: Hao Wu <hao.a.wu@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Feng Tian <feng.tian@intel.com>
---
 MdeModulePkg/Bus/Ufs/UfsPassThruDxe/UfsPassThruHci.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/MdeModulePkg/Bus/Ufs/UfsPassThruDxe/UfsPassThruHci.c b/MdeModulePkg/Bus/Ufs/UfsPassThruDxe/UfsPassThruHci.c
index 26986cb..a854264 100644
--- a/MdeModulePkg/Bus/Ufs/UfsPassThruDxe/UfsPassThruHci.c
+++ b/MdeModulePkg/Bus/Ufs/UfsPassThruDxe/UfsPassThruHci.c
@@ -399,6 +399,11 @@ UfsInitUtpPrdt (
   UINT32     RemainingLen;
   UINT8      *Remaining;
   UINTN      PrdtNumber;
+  
+  if ((BufferSize & (BIT0 | BIT1)) != 0) {
+    BufferSize &= ~(BIT0 | BIT1);
+    DEBUG ((EFI_D_WARN, "UfsInitUtpPrdt: The BufferSize [%d] is not dword-aligned!\n", BufferSize));
+  }
 
   if (BufferSize == 0) {
     return EFI_SUCCESS;
-- 
2.7.1.windows.2