EmbeddedPkg/RealTimeClockRuntimeDxe/RealTimeClock.c

   1 /** @file
   2   Implement EFI RealTimeClock runtime services via RTC Lib.
   3
   4   Copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>
   5   Copyright (c) 2017, Linaro, Ltd. All rights reserved.<BR>
   6
   7   This program and the accompanying materials
   8   are licensed and made available under the terms and conditions of the BSD License
   9   which accompanies this distribution.  The full text of the license may be found at
  10   http://opensource.org/licenses/bsd-license.php
  11
  12   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  13   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  14
  15 **/
  16
  17 #include <PiDxe.h>
  18 #include <Library/DebugLib.h>
  19 #include <Library/RealTimeClockLib.h>
  20 #include <Library/UefiLib.h>
  21 #include <Library/UefiBootServicesTableLib.h>
  22 #include <Library/UefiRuntimeLib.h>
  23 #include <Protocol/RealTimeClock.h>
  24
  25 EFI_HANDLE  mHandle = NULL;
  26
  27 //
  28 // These values can be set by SetTime () and need to be returned by GetTime ()
  29 // but cannot usually be kept by the RTC hardware, so we store them in a UEFI
  30 // variable instead.
  31 //
  32 typedef struct {
  33   INT16           TimeZone;
  34   UINT8           Daylight;
  35 } NON_VOLATILE_TIME_SETTINGS;
  36
  37 STATIC CONST CHAR16 mTimeSettingsVariableName[] = L"RtcTimeSettings";
  38 STATIC NON_VOLATILE_TIME_SETTINGS mTimeSettings;
  39
  40 STATIC
  41 BOOLEAN
  42 IsValidTimeZone (
  43   IN  INT16  TimeZone
  44   )
  45 {
  46   return TimeZone == EFI_UNSPECIFIED_TIMEZONE ||
  47          (TimeZone >= -1440 && TimeZone <= 1440);
  48 }
  49
  50 STATIC
  51 BOOLEAN
  52 IsValidDaylight (
  53   IN  INT8  Daylight
  54   )
  55 {
  56   return Daylight == 0 ||
  57          Daylight == EFI_TIME_ADJUST_DAYLIGHT ||
  58          Daylight == (EFI_TIME_ADJUST_DAYLIGHT | EFI_TIME_IN_DAYLIGHT);
  59 }
  60
  61 STATIC
  62 BOOLEAN
  63 EFIAPI
  64 IsLeapYear (
  65   IN EFI_TIME   *Time
  66   )
  67 {
  68   if (Time->Year % 4 == 0) {
  69     if (Time->Year % 100 == 0) {
  70       if (Time->Year % 400 == 0) {
  71         return TRUE;
  72       } else {
  73         return FALSE;
  74       }
  75     } else {
  76       return TRUE;
  77     }
  78   } else {
  79     return FALSE;
  80   }
  81 }
  82
  83 STATIC CONST INTN mDayOfMonth[12] = {
  84   31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
  85 };
  86
  87 STATIC
  88 BOOLEAN
  89 EFIAPI
  90 IsDayValid (
  91   IN  EFI_TIME  *Time
  92   )
  93 {
  94   ASSERT (Time->Day >= 1);
  95   ASSERT (Time->Day <= mDayOfMonth[Time->Month - 1]);
  96   ASSERT (Time->Month != 2 || IsLeapYear (Time) || Time->Day <= 28);
  97
  98   if (Time->Day < 1 ||
  99       Time->Day > mDayOfMonth[Time->Month - 1] ||
 100       (Time->Month == 2 && !IsLeapYear (Time) && Time->Day > 28)) {
 101     return FALSE;
 102   }
 103   return TRUE;
 104 }
 105
 106 STATIC
 107 BOOLEAN
 108 EFIAPI
 109 IsTimeValid(
 110   IN EFI_TIME *Time
 111   )
 112 {
 113   // Check the input parameters are within the range specified by UEFI
 114   if (Time->Year   < 1900               ||
 115       Time->Year   > 9999               ||
 116       Time->Month  < 1                  ||
 117       Time->Month  > 12                 ||
 118       !IsDayValid (Time)                ||
 119       Time->Hour   > 23                 ||
 120       Time->Minute > 59                 ||
 121       Time->Second > 59                 ||
 122       !IsValidTimeZone (Time->TimeZone) ||
 123       !IsValidDaylight (Time->Daylight)) {
 124     return FALSE;
 125   }
 126   return TRUE;
 127 }
 128
 129 /**
 130   Returns the current time and date information, and the time-keeping capabilities
 131   of the hardware platform.
 132
 133   @param  Time                  A pointer to storage to receive a snapshot of the current time.
 134   @param  Capabilities          An optional pointer to a buffer to receive the real time clock
 135                                 device's capabilities.
 136
 137   @retval EFI_SUCCESS           The operation completed successfully.
 138   @retval EFI_INVALID_PARAMETER Time is NULL.
 139   @retval EFI_DEVICE_ERROR      The time could not be retrieved due to hardware error.
 140
 141 **/
 142 EFI_STATUS
 143 EFIAPI
 144 GetTime (
 145   OUT EFI_TIME                *Time,
 146   OUT EFI_TIME_CAPABILITIES   *Capabilities
 147   )
 148 {
 149   if (Time == NULL) {
 150     return EFI_INVALID_PARAMETER;
 151   }
 152
 153   //
 154   // Set these first so the RealTimeClockLib implementation
 155   // can override them based on its own settings.
 156   //
 157   Time->TimeZone = mTimeSettings.TimeZone;
 158   Time->Daylight = mTimeSettings.Daylight;
 159
 160   return LibGetTime (Time, Capabilities);
 161 }
 162
 163
 164
 165 /**
 166   Sets the current local time and date information.
 167
 168   @param  Time                  A pointer to the current time.
 169
 170   @retval EFI_SUCCESS           The operation completed successfully.
 171   @retval EFI_INVALID_PARAMETER A time field is out of range.
 172   @retval EFI_DEVICE_ERROR      The time could not be set due due to hardware error.
 173
 174 **/
 175 EFI_STATUS
 176 EFIAPI
 177 SetTime (
 178   IN EFI_TIME                *Time
 179   )
 180 {
 181   EFI_STATUS        Status;
 182   BOOLEAN           TimeSettingsChanged;
 183
 184   if (Time == NULL || !IsTimeValid (Time)) {
 185     return EFI_INVALID_PARAMETER;
 186   }
 187
 188   TimeSettingsChanged = FALSE;
 189   if (mTimeSettings.TimeZone != Time->TimeZone ||
 190       mTimeSettings.Daylight != Time->Daylight) {
 191
 192     mTimeSettings.TimeZone = Time->TimeZone;
 193     mTimeSettings.Daylight = Time->Daylight;
 194     TimeSettingsChanged = TRUE;
 195   }
 196
 197   Status = LibSetTime (Time);
 198   if (EFI_ERROR (Status)) {
 199     return Status;
 200   }
 201
 202   if (TimeSettingsChanged) {
 203     Status = EfiSetVariable (
 204                (CHAR16 *)mTimeSettingsVariableName,
 205                &gEfiCallerIdGuid,
 206                EFI_VARIABLE_NON_VOLATILE |
 207                EFI_VARIABLE_BOOTSERVICE_ACCESS |
 208                EFI_VARIABLE_RUNTIME_ACCESS,
 209                sizeof (mTimeSettings),
 210                (VOID *)&mTimeSettings);
 211     if (EFI_ERROR (Status)) {
 212       return EFI_DEVICE_ERROR;
 213     }
 214   }
 215   return EFI_SUCCESS;
 216 }
 217
 218
 219 /**
 220   Returns the current wakeup alarm clock setting.
 221
 222   @param  Enabled               Indicates if the alarm is currently enabled or disabled.
 223   @param  Pending               Indicates if the alarm signal is pending and requires acknowledgement.
 224   @param  Time                  The current alarm setting.
 225
 226   @retval EFI_SUCCESS           The alarm settings were returned.
 227   @retval EFI_INVALID_PARAMETER Any parameter is NULL.
 228   @retval EFI_DEVICE_ERROR      The wakeup time could not be retrieved due to a hardware error.
 229
 230 **/
 231 EFI_STATUS
 232 EFIAPI
 233 GetWakeupTime (
 234   OUT BOOLEAN     *Enabled,
 235   OUT BOOLEAN     *Pending,
 236   OUT EFI_TIME    *Time
 237   )
 238 {
 239   return LibGetWakeupTime (Enabled, Pending, Time);
 240 }
 241
 242
 243 /**
 244   Sets the system wakeup alarm clock time.
 245
 246   @param  Enabled               Enable or disable the wakeup alarm.
 247   @param  Time                  If Enable is TRUE, the time to set the wakeup alarm for.
 248
 249   @retval EFI_SUCCESS           If Enable is TRUE, then the wakeup alarm was enabled. If
 250                                 Enable is FALSE, then the wakeup alarm was disabled.
 251   @retval EFI_INVALID_PARAMETER A time field is out of range.
 252   @retval EFI_DEVICE_ERROR      The wakeup time could not be set due to a hardware error.
 253   @retval EFI_UNSUPPORTED       A wakeup timer is not supported on this platform.
 254
 255 **/
 256 EFI_STATUS
 257 EFIAPI
 258 SetWakeupTime (
 259   IN BOOLEAN      Enabled,
 260   OUT EFI_TIME    *Time
 261   )
 262 {
 263   return LibSetWakeupTime (Enabled, Time);
 264 }
 265
 266
 267
 268 /**
 269   This is the declaration of an EFI image entry point. This can be the entry point to an application
 270   written to this specification, an EFI boot service driver, or an EFI runtime driver.
 271
 272   @param  ImageHandle           Handle that identifies the loaded image.
 273   @param  SystemTable           System Table for this image.
 274
 275   @retval EFI_SUCCESS           The operation completed successfully.
 276
 277 **/
 278 EFI_STATUS
 279 EFIAPI
 280 InitializeRealTimeClock (
 281   IN EFI_HANDLE                            ImageHandle,
 282   IN EFI_SYSTEM_TABLE                      *SystemTable
 283   )
 284 {
 285   EFI_STATUS  Status;
 286   UINTN       Size;
 287
 288   Status = LibRtcInitialize (ImageHandle, SystemTable);
 289   if (EFI_ERROR (Status)) {
 290     return Status;
 291   }
 292
 293   Size = sizeof (mTimeSettings);
 294   Status = EfiGetVariable ((CHAR16 *)mTimeSettingsVariableName,
 295              &gEfiCallerIdGuid, NULL, &Size, (VOID *)&mTimeSettings);
 296   if (EFI_ERROR (Status) ||
 297       !IsValidTimeZone (mTimeSettings.TimeZone) ||
 298       !IsValidDaylight (mTimeSettings.Daylight)) {
 299     DEBUG ((DEBUG_WARN, "%a: using default timezone/daylight settings\n",
 300       __FUNCTION__));
 301
 302     mTimeSettings.TimeZone = EFI_UNSPECIFIED_TIMEZONE;
 303     mTimeSettings.Daylight = 0;
 304   }
 305
 306   SystemTable->RuntimeServices->GetTime       = GetTime;
 307   SystemTable->RuntimeServices->SetTime       = SetTime;
 308   SystemTable->RuntimeServices->GetWakeupTime = GetWakeupTime;
 309   SystemTable->RuntimeServices->SetWakeupTime = SetWakeupTime;
 310
 311   Status = gBS->InstallMultipleProtocolInterfaces (
 312                   &mHandle,
 313                   &gEfiRealTimeClockArchProtocolGuid,
 314                   NULL,
 315                   NULL
 316                   );
 317
 318   return Status;
 319 }
 320