[edk2-platform][PATCH v1 1/1] EmbeddedPkg/VirtualRealTimeClockLib : Fix SetTime issues

["Sunny Wang" <Sunny.Wang@arm.com>]

This patch fixes two issues below:
1. SCT SetTime_Func failures.
   - https://github.com/pftf/RPi4/issues/164
2. Using shell time and date commands to set time can't work.

The problem is that gRT->SetTime always returns EFI_INVALID_PARAMETER
error status.

The root cause is that LibSetTime() sets RtcEpochSeconds variable with
inconsistent attributes. One is without EFI_VARIABLE_NON_VOLATILE,
the other one is with EFI_VARIABLE_NON_VOLATILE. That caused that the
variable driver returns EFI_INVALID_PARAMETER. Per UEFI spec, if a
preexisting variable is rewritten with different attributes,
SetVariable() shall not modify the variable and shall return
EFI_INVALID_PARAMETER.

Therefore, the solution is to add EFI_VARIABLE_NON_VOLATILE attribute
to the first EfiSetVariable() call to make two calls consistent.

By the way, this patch also fix a minor issue with a debug message.

Cc: Samer El-Haj-Mahmoud <samer.el-haj-mahmoud@arm.com>
Cc: Sami Mujawar <sami.mujawar@arm.com>
Cc: Jeremy Linton <jeremy.linton@arm.com>
Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Pete Batard <pete@akeo.ie>
Cc: Leif Lindholm <leif@nuviainc.com>

Signed-off-by: Sunny Wang <sunny.wang@arm.com>
---
 .../VirtualRealTimeClockLib/VirtualRealTimeClockLib.c       | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/EmbeddedPkg/Library/VirtualRealTimeClockLib/VirtualRealTimeClockLib.c b/EmbeddedPkg/Library/VirtualRealTimeClockLib/VirtualRealTimeClockLib.c
index de6fbb40e6..c10c91bc75 100644
--- a/EmbeddedPkg/Library/VirtualRealTimeClockLib/VirtualRealTimeClockLib.c
+++ b/EmbeddedPkg/Library/VirtualRealTimeClockLib/VirtualRealTimeClockLib.c
@@ -4,7 +4,7 @@
  *
  *  Coypright (c) 2019, Pete Batard <pete@akeo.ie>
  *  Copyright (c) 2018, Andrei Warkentin <andrey.warkentin@gmail.com>
- *  Copyright (c) 2011-2014, ARM Ltd. All rights reserved.
+ *  Copyright (c) 2011-2021, ARM Ltd. All rights reserved.
  *  Copyright (c) 2008-2010, Apple Inc. All rights reserved.
  *  Copyright (c) Microsoft Corporation. All rights reserved.
  *
@@ -96,7 +96,7 @@ LibGetTime (
     EfiSetVariable (
       (CHAR16 *)mEpochVariableName,
       &gEfiCallerIdGuid,
-      EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS,
+      EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS,
       sizeof (EpochSeconds),
       &EpochSeconds
       );
@@ -324,7 +324,7 @@ LibSetTime (
     DEBUG ((
       DEBUG_ERROR,
       "LibSetTime: Failed to save %s variable to non-volatile storage, Status = %r\n",
-      mDaylightVariableName,
+      mEpochVariableName,
       Status
       ));
     return Status;
-- 
2.31.0.windows.1