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+/** @file
+ Implement EFI RealTimeClock runtime services via Xen shared info page
+
+ Copyright (c) 2015, Linaro Ltd. All rights reserved.<BR>
+
+ 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 <Uefi.h>
+#include <PiDxe.h>
+#include <Library/BaseLib.h>
+#include <Library/DebugLib.h>
+
+/**
+ Converts Epoch seconds (elapsed since 1970 JANUARY 01, 00:00:00 UTC) to EFI_TIME
+ **/
+STATIC
+VOID
+EpochToEfiTime (
+ IN UINTN EpochSeconds,
+ OUT EFI_TIME *Time
+ )
+{
+ UINTN a;
+ UINTN b;
+ UINTN c;
+ UINTN d;
+ UINTN g;
+ UINTN j;
+ UINTN m;
+ UINTN y;
+ UINTN da;
+ UINTN db;
+ UINTN dc;
+ UINTN dg;
+ UINTN hh;
+ UINTN mm;
+ UINTN ss;
+ UINTN J;
+
+ J = (EpochSeconds / 86400) + 2440588;
+ j = J + 32044;
+ g = j / 146097;
+ dg = j % 146097;
+ c = (((dg / 36524) + 1) * 3) / 4;
+ dc = dg - (c * 36524);
+ b = dc / 1461;
+ db = dc % 1461;
+ a = (((db / 365) + 1) * 3) / 4;
+ da = db - (a * 365);
+ y = (g * 400) + (c * 100) + (b * 4) + a;
+ m = (((da * 5) + 308) / 153) - 2;
+ d = da - (((m + 4) * 153) / 5) + 122;
+
+ Time->Year = y - 4800 + ((m + 2) / 12);
+ Time->Month = ((m + 2) % 12) + 1;
+ Time->Day = d + 1;
+
+ ss = EpochSeconds % 60;
+ a = (EpochSeconds - ss) / 60;
+ mm = a % 60;
+ b = (a - mm) / 60;
+ hh = b % 24;
+
+ Time->Hour = hh;
+ Time->Minute = mm;
+ Time->Second = ss;
+ Time->Nanosecond = 0;
+
+}
+
+/**
+ Returns the current time and date information, and the time-keeping capabilities
+ of the hardware platform.
+
+ @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
+ )
+{
+ ASSERT (Time != NULL);
+
+ //
+ // For now, there is nothing that we can do besides returning a bogus time,
+ // as Xen's timekeeping uses a shared info page which cannot be shared
+ // between UEFI and the OS
+ //
+ EpochToEfiTime(1421770011, Time);
+
+ 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
+ )
+{
+ return EFI_DEVICE_ERROR;
+}
+
+
+/**
+ 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.
+ @retval EFI_UNSUPPORTED A wakeup timer is not supported on this platform.
+
+**/
+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;
+}
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+#/** @file
+#
+# Copyright (c) 2015, L Ltd. All rights reserved.<BR>
+#
+# 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 = 0x00010005
+ BASE_NAME = XenRealTimeClockLib
+ FILE_GUID = EC2557E8-7005-430B-9F6F-9BA109698248
+ MODULE_TYPE = BASE
+ VERSION_STRING = 1.0
+ LIBRARY_CLASS = RealTimeClockLib|DXE_CORE DXE_DRIVER UEFI_DRIVER DXE_RUNTIME_DRIVER UEFI_APPLICATION
+
+[Sources.common]
+ XenRealTimeClockLib.c
+
+[Packages]
+ MdePkg/MdePkg.dec
+ OvmfPkg/OvmfPkg.dec
+ EmbeddedPkg/EmbeddedPkg.dec
+
+[LibraryClasses]
+ UefiLib
+ DebugLib
+ DxeServicesTableLib
+ UefiRuntimeLib
+
+[Guids]
+ gEfiEventVirtualAddressChangeGuid
This implements a dummy RealTimeClockLib for Xen, as there is no guest interface to access the time kept by Xen that can be shared between UEFI and the OS. Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> --- OvmfPkg/Library/XenRealTimeClockLib/XenRealTimeClockLib.c | 196 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ OvmfPkg/Library/XenRealTimeClockLib/XenRealTimeClockLib.inf | 38 ++++++++++++++++ 2 files changed, 234 insertions(+)