[PATCH v4 edk2-platforms 06/23] Platform/Raspberry/Pi3: Add RTC library

[Pete Batard <pete@akeo.ie>]

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Pete Batard <pete@akeo.ie>
---
 Platform/Raspberry/Pi3/Library/VirtualRealTimeClockLib/VirtualRealTimeClockLib.c   | 221 ++++++++++++++++++++
 Platform/Raspberry/Pi3/Library/VirtualRealTimeClockLib/VirtualRealTimeClockLib.inf |  43 ++++
 2 files changed, 264 insertions(+)

diff --git a/Platform/Raspberry/Pi3/Library/VirtualRealTimeClockLib/VirtualRealTimeClockLib.c b/Platform/Raspberry/Pi3/Library/VirtualRealTimeClockLib/VirtualRealTimeClockLib.c
new file mode 100644
index 000000000000..dea621ff03ef
--- /dev/null
+++ b/Platform/Raspberry/Pi3/Library/VirtualRealTimeClockLib/VirtualRealTimeClockLib.c
@@ -0,0 +1,221 @@
+/** @file
+ *
+ *  Implement dummy EFI RealTimeClock runtime services.
+ *
+ *  Copyright (c) 2018, Andrei Warkentin <andrey.warkentin@gmail.com>
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *
+ *  This program and the accompanying materials
+ *  are licensed and made available under the terms and conditions of the BSD License
+ *  which accompanies this distribution.  The full text of the license may be found at
+ *  http://opensource.org/licenses/bsd-license.php
+ *
+ *  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+ *
+ **/
+
+#include <PiDxe.h>
+#include <Library/BaseLib.h>
+#include <Library/DebugLib.h>
+#include <Library/IoLib.h>
+#include <Library/RealTimeClockLib.h>
+#include <Library/TimerLib.h>
+#include <Library/TimeBaseLib.h>
+#include <Library/UefiRuntimeLib.h>
+#include <Library/ArmGenericTimerCounterLib.h>
+
+/**
+   Returns the current time and date information, and the time-keeping capabilities
+   of the virtual RTC.
+
+   For simplicity, this LibGetTime does not report Years/Months, instead it will only report current
+   Day, Hours, Minutes and Seconds starting from the begining of CPU up-time. Otherwise, a more
+   complex logic will be required to account for leap years and days/month differences.
+
+   @param  Time                  A pointer to storage to receive a snapshot of the current time.
+   @param  Capabilities          An optional pointer to a buffer to receive the real time clock
+   device's capabilities.
+
+   @retval EFI_SUCCESS           The operation completed successfully.
+   @retval EFI_INVALID_PARAMETER Time is NULL.
+   @retval EFI_DEVICE_ERROR      The time could not be retrieved due to hardware error.
+
+**/
+EFI_STATUS
+EFIAPI
+LibGetTime (
+  OUT EFI_TIME               *Time,
+  OUT EFI_TIME_CAPABILITIES  *Capabilities
+  )
+{
+  UINTN DataSize;
+  UINT64 Counter;
+  EFI_STATUS Status;
+  UINTN ElapsedSeconds;
+  UINT32 Remainder;
+  UINT32 Freq = ArmGenericTimerGetTimerFreq ();
+
+  if (Time == NULL) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  //
+  // Depend on ARM generic timer to report date/time relative to the
+  // start of CPU timer counting where date and time will always
+  // be relative to the date/time 1/1/1900 00H:00M:00S
+  //
+
+  ASSERT (Freq != 0);
+  if (Freq == 0) {
+    return EFI_DEVICE_ERROR;
+  }
+
+  if (Capabilities) {
+    Capabilities->Accuracy = 0;
+    Capabilities->Resolution = Freq;
+    Capabilities->SetsToZero = FALSE;
+  }
+
+  DataSize = sizeof (UINTN);
+  ElapsedSeconds = 0;
+  Status = EfiGetVariable (L"RtcEpochSeconds",
+             &gEfiCallerIdGuid,
+             NULL,
+             &DataSize,
+             &ElapsedSeconds);
+  if (EFI_ERROR (Status)) {
+    ElapsedSeconds = PcdGet64 (PcdBootEpochSeconds);
+  }
+  Counter = GetPerformanceCounter ();
+  ElapsedSeconds += DivU64x32Remainder (Counter, Freq, &Remainder);
+  EpochToEfiTime (ElapsedSeconds, Time);
+
+  //
+  // Frequency < 0x100000000, so Remainder < 0x100000000, then (Remainder * 1,000,000,000)
+  // will not overflow 64-bit.
+  //
+  Time->Nanosecond = DivU64x32 (MultU64x64 ((UINT64)Remainder, 1000000000U), Freq);
+
+  return EFI_SUCCESS;
+}
+
+
+/**
+   Sets the current local time and date information.
+
+   @param  Time                  A pointer to the current time.
+
+   @retval EFI_SUCCESS           The operation completed successfully.
+   @retval EFI_INVALID_PARAMETER A time field is out of range.
+   @retval EFI_DEVICE_ERROR      The time could not be set due due to hardware error.
+
+**/
+EFI_STATUS
+EFIAPI
+LibSetTime (
+  IN EFI_TIME  *Time
+  )
+{
+  UINTN Epoch;
+
+  if (!IsTimeValid (Time)) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  Epoch = EfiTimeToEpoch (Time);
+  return EfiSetVariable (L"RtcEpochSeconds", &gEfiCallerIdGuid,
+           EFI_VARIABLE_BOOTSERVICE_ACCESS |
+           EFI_VARIABLE_RUNTIME_ACCESS |
+           EFI_VARIABLE_NON_VOLATILE,
+           sizeof (Epoch),
+           &Epoch);
+}
+
+
+/**
+   Returns the current wakeup alarm clock setting.
+
+   @param  Enabled               Indicates if the alarm is currently enabled or disabled.
+   @param  Pending               Indicates if the alarm signal is pending and requires acknowledgement.
+   @param  Time                  The current alarm setting.
+
+   @retval EFI_SUCCESS           The alarm settings were returned.
+   @retval EFI_INVALID_PARAMETER Any parameter is NULL.
+   @retval EFI_DEVICE_ERROR      The wakeup time could not be retrieved due to a hardware error.
+
+**/
+EFI_STATUS
+EFIAPI
+LibGetWakeupTime (
+  OUT BOOLEAN   *Enabled,
+  OUT BOOLEAN   *Pending,
+  OUT EFI_TIME  *Time
+  )
+{
+  return EFI_UNSUPPORTED;
+}
+
+
+/**
+   Sets the system wakeup alarm clock time.
+
+   @param  Enabled               Enable or disable the wakeup alarm.
+   @param  Time                  If Enable is TRUE, the time to set the wakeup alarm for.
+
+   @retval EFI_SUCCESS           If Enable is TRUE, then the wakeup alarm was enabled. If
+   Enable is FALSE, then the wakeup alarm was disabled.
+   @retval EFI_INVALID_PARAMETER A time field is out of range.
+   @retval EFI_DEVICE_ERROR      The wakeup time could not be set due to a hardware error.
+   @retval EFI_UNSUPPORTED       A wakeup timer is not supported on this platform.
+
+**/
+EFI_STATUS
+EFIAPI
+LibSetWakeupTime (
+  IN  BOOLEAN   Enabled,
+  OUT EFI_TIME  *Time
+  )
+{
+  return EFI_UNSUPPORTED;
+}
+
+
+/**
+   This is the declaration of an EFI image entry point. This can be the entry point to an application
+   written to this specification, an EFI boot service driver, or an EFI runtime driver.
+
+   @param  ImageHandle           Handle that identifies the loaded image.
+   @param  SystemTable           System Table for this image.
+
+   @retval EFI_SUCCESS           The operation completed successfully.
+
+**/
+EFI_STATUS
+EFIAPI
+LibRtcInitialize (
+  IN EFI_HANDLE        ImageHandle,
+  IN EFI_SYSTEM_TABLE  *SystemTable
+  )
+{
+  return EFI_SUCCESS;
+}
+
+
+/**
+   Fixup internal data so that EFI can be call in virtual mode.
+   Call the passed in Child Notify event and convert any pointers in
+   lib to virtual mode.
+
+   @param[in]    Event   The Event that is being processed
+   @param[in]    Context Event Context
+**/
+VOID
+EFIAPI
+LibRtcVirtualNotifyEvent (
+  IN EFI_EVENT  Event,
+  IN VOID       *Context
+  )
+{
+  return;
+}
diff --git a/Platform/Raspberry/Pi3/Library/VirtualRealTimeClockLib/VirtualRealTimeClockLib.inf b/Platform/Raspberry/Pi3/Library/VirtualRealTimeClockLib/VirtualRealTimeClockLib.inf
new file mode 100644
index 000000000000..5c39e4df4c34
--- /dev/null
+++ b/Platform/Raspberry/Pi3/Library/VirtualRealTimeClockLib/VirtualRealTimeClockLib.inf
@@ -0,0 +1,43 @@
+#/** @file
+#
+#  Implement dummy EFI RealTimeClock runtime services.
+#
+#  Copyright (c) 2018, Andrei Warkentin <andrey.warkentin@gmail.com>
+#  Copyright (c) Microsoft Corporation. All rights reserved.
+#
+#  This program and the accompanying materials
+#  are licensed and made available under the terms and conditions of the BSD License
+#  which accompanies this distribution.  The full text of the license may be found at
+#  http://opensource.org/licenses/bsd-license.php
+#
+#  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+#
+#**/
+
+[Defines]
+  INF_VERSION                    = 0x0001001A
+  BASE_NAME                      = VirtualRealTimeClockLib
+  FILE_GUID                      = 1E27D461-78F3-4F7D-B1C2-F72384F13A6E
+  MODULE_TYPE                    = BASE
+  VERSION_STRING                 = 1.0
+  LIBRARY_CLASS                  = RealTimeClockLib
+
+[Sources.common]
+  VirtualRealTimeClockLib.c
+
+[Packages]
+  ArmPkg/ArmPkg.dec
+  MdePkg/MdePkg.dec
+  EmbeddedPkg/EmbeddedPkg.dec
+  Platform/Raspberry/Pi3/RPi3.dec
+
+[LibraryClasses]
+  IoLib
+  DebugLib
+  TimerLib
+  TimeBaseLib
+  UefiRuntimeLib
+
+[Pcd]
+  gRaspberryPiTokenSpaceGuid.PcdBootEpochSeconds
-- 
2.17.0.windows.1