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   SPDX-License-Identifier: BSD-2-Clause-Patent
   8
   9 **/
  10
  11 #include <PiDxe.h>
  12 #include <Library/DebugLib.h>
  13 #include <Library/RealTimeClockLib.h>
  14 #include <Library/UefiLib.h>
  15 #include <Library/UefiBootServicesTableLib.h>
  16 #include <Library/UefiRuntimeLib.h>
  17 #include <Protocol/RealTimeClock.h>
  18
  19 EFI_HANDLE  mHandle = NULL;
  20
  21 //
  22 // These values can be set by SetTime () and need to be returned by GetTime ()
  23 // but cannot usually be kept by the RTC hardware, so we store them in a UEFI
  24 // variable instead.
  25 //
  26 typedef struct {
  27   INT16           TimeZone;
  28   UINT8           Daylight;
  29 } NON_VOLATILE_TIME_SETTINGS;
  30
  31 STATIC CONST CHAR16 mTimeSettingsVariableName[] = L"RtcTimeSettings";
  32 STATIC NON_VOLATILE_TIME_SETTINGS mTimeSettings;
  33
  34 STATIC
  35 BOOLEAN
  36 IsValidTimeZone (
  37   IN  INT16  TimeZone
  38   )
  39 {
  40   return TimeZone == EFI_UNSPECIFIED_TIMEZONE ||
  41          (TimeZone >= -1440 && TimeZone <= 1440);
  42 }
  43
  44 STATIC
  45 BOOLEAN
  46 IsValidDaylight (
  47   IN  INT8  Daylight
  48   )
  49 {
  50   return Daylight == 0 ||
  51          Daylight == EFI_TIME_ADJUST_DAYLIGHT ||
  52          Daylight == (EFI_TIME_ADJUST_DAYLIGHT | EFI_TIME_IN_DAYLIGHT);
  53 }
  54
  55 STATIC
  56 BOOLEAN
  57 EFIAPI
  58 IsLeapYear (
  59   IN EFI_TIME   *Time
  60   )
  61 {
  62   if (Time->Year % 4 == 0) {
  63     if (Time->Year % 100 == 0) {
  64       if (Time->Year % 400 == 0) {
  65         return TRUE;
  66       } else {
  67         return FALSE;
  68       }
  69     } else {
  70       return TRUE;
  71     }
  72   } else {
  73     return FALSE;
  74   }
  75 }
  76
  77 STATIC CONST INTN mDayOfMonth[12] = {
  78   31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
  79 };
  80
  81 STATIC
  82 BOOLEAN
  83 EFIAPI
  84 IsDayValid (
  85   IN  EFI_TIME  *Time
  86   )
  87 {
  88   ASSERT (Time->Day >= 1);
  89   ASSERT (Time->Day <= mDayOfMonth[Time->Month - 1]);
  90   ASSERT (Time->Month != 2 || IsLeapYear (Time) || Time->Day <= 28);
  91
  92   if (Time->Day < 1 ||
  93       Time->Day > mDayOfMonth[Time->Month - 1] ||
  94       (Time->Month == 2 && !IsLeapYear (Time) && Time->Day > 28)) {
  95     return FALSE;
  96   }
  97   return TRUE;
  98 }
  99
 100 STATIC
 101 BOOLEAN
 102 EFIAPI
 103 IsTimeValid(
 104   IN EFI_TIME *Time
 105   )
 106 {
 107   // Check the input parameters are within the range specified by UEFI
 108   if (Time->Year   < 1900               ||
 109       Time->Year   > 9999               ||
 110       Time->Month  < 1                  ||
 111       Time->Month  > 12                 ||
 112       !IsDayValid (Time)                ||
 113       Time->Hour   > 23                 ||
 114       Time->Minute > 59                 ||
 115       Time->Second > 59                 ||
 116       !IsValidTimeZone (Time->TimeZone) ||
 117       !IsValidDaylight (Time->Daylight)) {
 118     return FALSE;
 119   }
 120   return TRUE;
 121 }
 122
 123 /**
 124   Returns the current time and date information, and the time-keeping capabilities
 125   of the hardware platform.
 126
 127   @param  Time                  A pointer to storage to receive a snapshot of the current time.
 128   @param  Capabilities          An optional pointer to a buffer to receive the real time clock
 129                                 device's capabilities.
 130
 131   @retval EFI_SUCCESS           The operation completed successfully.
 132   @retval EFI_INVALID_PARAMETER Time is NULL.
 133   @retval EFI_DEVICE_ERROR      The time could not be retrieved due to hardware error.
 134
 135 **/
 136 EFI_STATUS
 137 EFIAPI
 138 GetTime (
 139   OUT EFI_TIME                *Time,
 140   OUT EFI_TIME_CAPABILITIES   *Capabilities
 141   )
 142 {
 143   if (Time == NULL) {
 144     return EFI_INVALID_PARAMETER;
 145   }
 146
 147   //
 148   // Set these first so the RealTimeClockLib implementation
 149   // can override them based on its own settings.
 150   //
 151   Time->TimeZone = mTimeSettings.TimeZone;
 152   Time->Daylight = mTimeSettings.Daylight;
 153
 154   return LibGetTime (Time, Capabilities);
 155 }
 156
 157
 158
 159 /**
 160   Sets the current local time and date information.
 161
 162   @param  Time                  A pointer to the current time.
 163
 164   @retval EFI_SUCCESS           The operation completed successfully.
 165   @retval EFI_INVALID_PARAMETER A time field is out of range.
 166   @retval EFI_DEVICE_ERROR      The time could not be set due due to hardware error.
 167
 168 **/
 169 EFI_STATUS
 170 EFIAPI
 171 SetTime (
 172   IN EFI_TIME                *Time
 173   )
 174 {
 175   EFI_STATUS        Status;
 176   BOOLEAN           TimeSettingsChanged;
 177
 178   if (Time == NULL || !IsTimeValid (Time)) {
 179     return EFI_INVALID_PARAMETER;
 180   }
 181
 182   TimeSettingsChanged = FALSE;
 183   if (mTimeSettings.TimeZone != Time->TimeZone ||
 184       mTimeSettings.Daylight != Time->Daylight) {
 185
 186     mTimeSettings.TimeZone = Time->TimeZone;
 187     mTimeSettings.Daylight = Time->Daylight;
 188     TimeSettingsChanged = TRUE;
 189   }
 190
 191   Status = LibSetTime (Time);
 192   if (EFI_ERROR (Status)) {
 193     return Status;
 194   }
 195
 196   if (TimeSettingsChanged) {
 197     Status = EfiSetVariable (
 198                (CHAR16 *)mTimeSettingsVariableName,
 199                &gEfiCallerIdGuid,
 200                EFI_VARIABLE_NON_VOLATILE |
 201                EFI_VARIABLE_BOOTSERVICE_ACCESS |
 202                EFI_VARIABLE_RUNTIME_ACCESS,
 203                sizeof (mTimeSettings),
 204                (VOID *)&mTimeSettings);
 205     if (EFI_ERROR (Status)) {
 206       return EFI_DEVICE_ERROR;
 207     }
 208   }
 209   return EFI_SUCCESS;
 210 }
 211
 212
 213 /**
 214   Returns the current wakeup alarm clock setting.
 215
 216   @param  Enabled               Indicates if the alarm is currently enabled or disabled.
 217   @param  Pending               Indicates if the alarm signal is pending and requires acknowledgement.
 218   @param  Time                  The current alarm setting.
 219
 220   @retval EFI_SUCCESS           The alarm settings were returned.
 221   @retval EFI_INVALID_PARAMETER Any parameter is NULL.
 222   @retval EFI_DEVICE_ERROR      The wakeup time could not be retrieved due to a hardware error.
 223
 224 **/
 225 EFI_STATUS
 226 EFIAPI
 227 GetWakeupTime (
 228   OUT BOOLEAN     *Enabled,
 229   OUT BOOLEAN     *Pending,
 230   OUT EFI_TIME    *Time
 231   )
 232 {
 233   return LibGetWakeupTime (Enabled, Pending, Time);
 234 }
 235
 236
 237 /**
 238   Sets the system wakeup alarm clock time.
 239
 240   @param  Enabled               Enable or disable the wakeup alarm.
 241   @param  Time                  If Enable is TRUE, the time to set the wakeup alarm for.
 242
 243   @retval EFI_SUCCESS           If Enable is TRUE, then the wakeup alarm was enabled. If
 244                                 Enable is FALSE, then the wakeup alarm was disabled.
 245   @retval EFI_INVALID_PARAMETER A time field is out of range.
 246   @retval EFI_DEVICE_ERROR      The wakeup time could not be set due to a hardware error.
 247   @retval EFI_UNSUPPORTED       A wakeup timer is not supported on this platform.
 248
 249 **/
 250 EFI_STATUS
 251 EFIAPI
 252 SetWakeupTime (
 253   IN BOOLEAN      Enabled,
 254   OUT EFI_TIME    *Time
 255   )
 256 {
 257   return LibSetWakeupTime (Enabled, Time);
 258 }
 259
 260
 261
 262 /**
 263   This is the declaration of an EFI image entry point. This can be the entry point to an application
 264   written to this specification, an EFI boot service driver, or an EFI runtime driver.
 265
 266   @param  ImageHandle           Handle that identifies the loaded image.
 267   @param  SystemTable           System Table for this image.
 268
 269   @retval EFI_SUCCESS           The operation completed successfully.
 270
 271 **/
 272 EFI_STATUS
 273 EFIAPI
 274 InitializeRealTimeClock (
 275   IN EFI_HANDLE                            ImageHandle,
 276   IN EFI_SYSTEM_TABLE                      *SystemTable
 277   )
 278 {
 279   EFI_STATUS  Status;
 280   UINTN       Size;
 281
 282   Status = LibRtcInitialize (ImageHandle, SystemTable);
 283   if (EFI_ERROR (Status)) {
 284     return Status;
 285   }
 286
 287   Size = sizeof (mTimeSettings);
 288   Status = EfiGetVariable ((CHAR16 *)mTimeSettingsVariableName,
 289              &gEfiCallerIdGuid, NULL, &Size, (VOID *)&mTimeSettings);
 290   if (EFI_ERROR (Status) ||
 291       !IsValidTimeZone (mTimeSettings.TimeZone) ||
 292       !IsValidDaylight (mTimeSettings.Daylight)) {
 293     DEBUG ((DEBUG_WARN, "%a: using default timezone/daylight settings\n",
 294       __FUNCTION__));
 295
 296     mTimeSettings.TimeZone = EFI_UNSPECIFIED_TIMEZONE;
 297     mTimeSettings.Daylight = 0;
 298   }
 299
 300   SystemTable->RuntimeServices->GetTime       = GetTime;
 301   SystemTable->RuntimeServices->SetTime       = SetTime;
 302   SystemTable->RuntimeServices->GetWakeupTime = GetWakeupTime;
 303   SystemTable->RuntimeServices->SetWakeupTime = SetWakeupTime;
 304
 305   Status = gBS->InstallMultipleProtocolInterfaces (
 306                   &mHandle,
 307                   &gEfiRealTimeClockArchProtocolGuid,
 308                   NULL,
 309                   NULL
 310                   );
 311
 312   return Status;
 313 }
 314