[PATCH] MdeModulePkg/UfsPassThru : Fix UFS flag read from Query Resp UPIU

[sachin.agrawal@intel.com]

As per UFS spec, flag value is stored in the 'last byte' of value
field. Existing code is attempting to read first byte.

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2208

Test: Verified the Fix by sending command to set fPowerOnWPEn flag
and then reading it to verify the set value.

Cc: Hao A Wu <hao.a.wu@intel.com>
Cc: Ray Ni <ray.ni@intel.com>

Signed-off-by: Sachin Agrawal <sachin.agrawal@intel.com>
---
 MdeModulePkg/Bus/Ufs/UfsBlockIoPei/UfsHci.c          | 5 ++++-
 MdeModulePkg/Bus/Ufs/UfsPassThruDxe/UfsPassThruHci.c | 5 ++++-
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/MdeModulePkg/Bus/Ufs/UfsBlockIoPei/UfsHci.c b/MdeModulePkg/Bus/Ufs/UfsBlockIoPei/UfsHci.c
index e8ef0c2a7a..e450f6f49d 100644
--- a/MdeModulePkg/Bus/Ufs/UfsBlockIoPei/UfsHci.c
+++ b/MdeModulePkg/Bus/Ufs/UfsBlockIoPei/UfsHci.c
@@ -977,7 +977,10 @@ UfsRwFlags (
   }
 
   if (Trd->Ocs == 0) {
-    *Value = (UINT8)QueryResp->Tsf.Value;
+    //
+    // The 'FLAG VALUE' field is at byte offset 3 of QueryResp->Tsf.Value
+    //
+    *Value = *((UINT8*)&(QueryResp->Tsf.Value) + 3);
   } else {
     Status = EFI_DEVICE_ERROR;
   }
diff --git a/MdeModulePkg/Bus/Ufs/UfsPassThruDxe/UfsPassThruHci.c b/MdeModulePkg/Bus/Ufs/UfsPassThruDxe/UfsPassThruHci.c
index 0b95e7dddd..93ac958f65 100644
--- a/MdeModulePkg/Bus/Ufs/UfsPassThruDxe/UfsPassThruHci.c
+++ b/MdeModulePkg/Bus/Ufs/UfsPassThruDxe/UfsPassThruHci.c
@@ -863,7 +863,10 @@ UfsGetReturnDataFromQueryResponse (
     case UtpQueryFuncOpcodeSetFlag:
     case UtpQueryFuncOpcodeClrFlag:
     case UtpQueryFuncOpcodeTogFlag:
-      CopyMem (Packet->DataBuffer, &QueryResp->Tsf.Value, sizeof (UINT8));
+      //
+      // The 'FLAG VALUE' field is at byte offset 3 of QueryResp->Tsf.Value
+      //
+      *((UINT8*)(Packet->DataBuffer)) = *((UINT8*)&(QueryResp->Tsf.Value) + 3);
       break;
     case UtpQueryFuncOpcodeRdAttr:
     case UtpQueryFuncOpcodeWrAttr:
-- 
2.14.3.windows.1