ArmPlatformPkg/Library/PL031RealTimeClockLib/PL031RealTimeClockLib.c

   1 /** @file
   2   Implement EFI RealTimeClock runtime services via RTC Lib.
   3
   4   Copyright (c) 2008 - 2010, Apple Inc. All rights reserved.<BR>
   5   Copyright (c) 2011 - 2014, ARM 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 <Uefi.h>
  18 #include <PiDxe.h>
  19 #include <Library/BaseLib.h>
  20 #include <Library/DebugLib.h>
  21 #include <Library/UefiLib.h>
  22 #include <Library/IoLib.h>
  23 #include <Library/RealTimeClockLib.h>
  24 #include <Library/MemoryAllocationLib.h>
  25 #include <Library/PcdLib.h>
  26 #include <Library/DxeServicesTableLib.h>
  27 #include <Library/UefiBootServicesTableLib.h>
  28 #include <Library/UefiRuntimeServicesTableLib.h>
  29 #include <Library/UefiRuntimeLib.h>
  30
  31 #include <Protocol/RealTimeClock.h>
  32
  33 #include <Guid/GlobalVariable.h>
  34 #include <Guid/EventGroup.h>
  35
  36 #include <Drivers/PL031RealTimeClock.h>
  37
  38 #include <Library/TimeBaseLib.h>
  39
  40 STATIC BOOLEAN                mPL031Initialized = FALSE;
  41 STATIC EFI_EVENT              mRtcVirtualAddrChangeEvent;
  42 STATIC UINTN                  mPL031RtcBase;
  43
  44 EFI_STATUS
  45 IdentifyPL031 (
  46   VOID
  47   )
  48 {
  49   EFI_STATUS    Status;
  50
  51   // Check if this is a PrimeCell Peripheral
  52   if (  (MmioRead8 (mPL031RtcBase + PL031_RTC_PCELL_ID0) != 0x0D)
  53       || (MmioRead8 (mPL031RtcBase + PL031_RTC_PCELL_ID1) != 0xF0)
  54       || (MmioRead8 (mPL031RtcBase + PL031_RTC_PCELL_ID2) != 0x05)
  55       || (MmioRead8 (mPL031RtcBase + PL031_RTC_PCELL_ID3) != 0xB1)) {
  56     Status = EFI_NOT_FOUND;
  57     goto EXIT;
  58   }
  59
  60   // Check if this PrimeCell Peripheral is the PL031 Real Time Clock
  61   if (  (MmioRead8 (mPL031RtcBase + PL031_RTC_PERIPH_ID0) != 0x31)
  62       || (MmioRead8 (mPL031RtcBase + PL031_RTC_PERIPH_ID1) != 0x10)
  63       || ((MmioRead8 (mPL031RtcBase + PL031_RTC_PERIPH_ID2) & 0xF) != 0x04)
  64       || (MmioRead8 (mPL031RtcBase + PL031_RTC_PERIPH_ID3) != 0x00)) {
  65     Status = EFI_NOT_FOUND;
  66     goto EXIT;
  67   }
  68
  69   Status = EFI_SUCCESS;
  70
  71   EXIT:
  72   return Status;
  73 }
  74
  75 EFI_STATUS
  76 InitializePL031 (
  77   VOID
  78   )
  79 {
  80   EFI_STATUS    Status;
  81
  82   // Prepare the hardware
  83   Status = IdentifyPL031();
  84   if (EFI_ERROR (Status)) {
  85     goto EXIT;
  86   }
  87
  88   // Ensure interrupts are masked. We do not want RTC interrupts in UEFI
  89   if ((MmioRead32 (mPL031RtcBase + PL031_RTC_IMSC_IRQ_MASK_SET_CLEAR_REGISTER) & PL031_SET_IRQ_MASK) != PL031_SET_IRQ_MASK) {
  90     MmioOr32 (mPL031RtcBase + PL031_RTC_IMSC_IRQ_MASK_SET_CLEAR_REGISTER, PL031_SET_IRQ_MASK);
  91   }
  92
  93   // Clear any existing interrupts
  94   if ((MmioRead32 (mPL031RtcBase + PL031_RTC_RIS_RAW_IRQ_STATUS_REGISTER) & PL031_IRQ_TRIGGERED) == PL031_IRQ_TRIGGERED) {
  95     MmioOr32 (mPL031RtcBase + PL031_RTC_ICR_IRQ_CLEAR_REGISTER, PL031_CLEAR_IRQ);
  96   }
  97
  98   // Start the clock counter
  99   if ((MmioRead32 (mPL031RtcBase + PL031_RTC_CR_CONTROL_REGISTER) & PL031_RTC_ENABLED) != PL031_RTC_ENABLED) {
 100     MmioOr32 (mPL031RtcBase + PL031_RTC_CR_CONTROL_REGISTER, PL031_RTC_ENABLED);
 101   }
 102
 103   mPL031Initialized = TRUE;
 104
 105   EXIT:
 106   return Status;
 107 }
 108
 109 /**
 110   Returns the current time and date information, and the time-keeping capabilities
 111   of the hardware platform.
 112
 113   @param  Time                   A pointer to storage to receive a snapshot of the current time.
 114   @param  Capabilities           An optional pointer to a buffer to receive the real time clock
 115                                  device's capabilities.
 116
 117   @retval EFI_SUCCESS            The operation completed successfully.
 118   @retval EFI_INVALID_PARAMETER  Time is NULL.
 119   @retval EFI_DEVICE_ERROR       The time could not be retrieved due to hardware error.
 120   @retval EFI_SECURITY_VIOLATION The time could not be retrieved due to an authentication failure.
 121
 122 **/
 123 EFI_STATUS
 124 EFIAPI
 125 LibGetTime (
 126   OUT EFI_TIME                *Time,
 127   OUT EFI_TIME_CAPABILITIES   *Capabilities
 128   )
 129 {
 130   EFI_STATUS  Status = EFI_SUCCESS;
 131   UINT32      EpochSeconds;
 132
 133   // Ensure Time is a valid pointer
 134   if (Time == NULL) {
 135     return EFI_INVALID_PARAMETER;
 136   }
 137
 138   // Initialize the hardware if not already done
 139   if (!mPL031Initialized) {
 140     Status = InitializePL031 ();
 141     if (EFI_ERROR (Status)) {
 142       return Status;
 143     }
 144   }
 145
 146   EpochSeconds = MmioRead32 (mPL031RtcBase + PL031_RTC_DR_DATA_REGISTER);
 147
 148   // Adjust for the correct time zone
 149   // The timezone setting also reflects the DST setting of the clock
 150   if (Time->TimeZone != EFI_UNSPECIFIED_TIMEZONE) {
 151     EpochSeconds += Time->TimeZone * SEC_PER_MIN;
 152   } else if ((Time->Daylight & EFI_TIME_IN_DAYLIGHT) == EFI_TIME_IN_DAYLIGHT) {
 153     // Convert to adjusted time, i.e. spring forwards one hour
 154     EpochSeconds += SEC_PER_HOUR;
 155   }
 156
 157   // Convert from internal 32-bit time to UEFI time
 158   EpochToEfiTime (EpochSeconds, Time);
 159
 160   // Update the Capabilities info
 161   if (Capabilities != NULL) {
 162     // PL031 runs at frequency 1Hz
 163     Capabilities->Resolution  = PL031_COUNTS_PER_SECOND;
 164     // Accuracy in ppm multiplied by 1,000,000, e.g. for 50ppm set 50,000,000
 165     Capabilities->Accuracy    = (UINT32)PcdGet32 (PcdPL031RtcPpmAccuracy);
 166     // FALSE: Setting the time does not clear the values below the resolution level
 167     Capabilities->SetsToZero  = FALSE;
 168   }
 169
 170   return EFI_SUCCESS;
 171 }
 172
 173
 174 /**
 175   Sets the current local time and date information.
 176
 177   @param  Time                  A pointer to the current time.
 178
 179   @retval EFI_SUCCESS           The operation completed successfully.
 180   @retval EFI_INVALID_PARAMETER A time field is out of range.
 181   @retval EFI_DEVICE_ERROR      The time could not be set due due to hardware error.
 182
 183 **/
 184 EFI_STATUS
 185 EFIAPI
 186 LibSetTime (
 187   IN  EFI_TIME                *Time
 188   )
 189 {
 190   EFI_STATUS  Status;
 191   UINTN       EpochSeconds;
 192
 193   // Because the PL031 is a 32-bit counter counting seconds,
 194   // the maximum time span is just over 136 years.
 195   // Time is stored in Unix Epoch format, so it starts in 1970,
 196   // Therefore it can not exceed the year 2106.
 197   if ((Time->Year < 1970) || (Time->Year >= 2106)) {
 198     return EFI_UNSUPPORTED;
 199   }
 200
 201   // Initialize the hardware if not already done
 202   if (!mPL031Initialized) {
 203     Status = InitializePL031 ();
 204     if (EFI_ERROR (Status)) {
 205       return Status;
 206     }
 207   }
 208
 209   EpochSeconds = EfiTimeToEpoch (Time);
 210
 211   // Adjust for the correct time zone, i.e. convert to UTC time zone
 212   // The timezone setting also reflects the DST setting of the clock
 213   if (Time->TimeZone != EFI_UNSPECIFIED_TIMEZONE) {
 214     EpochSeconds -= Time->TimeZone * SEC_PER_MIN;
 215   } else if ((Time->Daylight & EFI_TIME_IN_DAYLIGHT) == EFI_TIME_IN_DAYLIGHT) {
 216     // Convert to un-adjusted time, i.e. fall back one hour
 217     EpochSeconds -= SEC_PER_HOUR;
 218   }
 219
 220   // Set the PL031
 221   MmioWrite32 (mPL031RtcBase + PL031_RTC_LR_LOAD_REGISTER, EpochSeconds);
 222
 223   return EFI_SUCCESS;
 224 }
 225
 226
 227 /**
 228   Returns the current wakeup alarm clock setting.
 229
 230   @param  Enabled               Indicates if the alarm is currently enabled or disabled.
 231   @param  Pending               Indicates if the alarm signal is pending and requires acknowledgement.
 232   @param  Time                  The current alarm setting.
 233
 234   @retval EFI_SUCCESS           The alarm settings were returned.
 235   @retval EFI_INVALID_PARAMETER Any parameter is NULL.
 236   @retval EFI_DEVICE_ERROR      The wakeup time could not be retrieved due to a hardware error.
 237
 238 **/
 239 EFI_STATUS
 240 EFIAPI
 241 LibGetWakeupTime (
 242   OUT BOOLEAN     *Enabled,
 243   OUT BOOLEAN     *Pending,
 244   OUT EFI_TIME    *Time
 245   )
 246 {
 247   // Not a required feature
 248   return EFI_UNSUPPORTED;
 249 }
 250
 251
 252 /**
 253   Sets the system wakeup alarm clock time.
 254
 255   @param  Enabled               Enable or disable the wakeup alarm.
 256   @param  Time                  If Enable is TRUE, the time to set the wakeup alarm for.
 257
 258   @retval EFI_SUCCESS           If Enable is TRUE, then the wakeup alarm was enabled. If
 259                                 Enable is FALSE, then the wakeup alarm was disabled.
 260   @retval EFI_INVALID_PARAMETER A time field is out of range.
 261   @retval EFI_DEVICE_ERROR      The wakeup time could not be set due to a hardware error.
 262   @retval EFI_UNSUPPORTED       A wakeup timer is not supported on this platform.
 263
 264 **/
 265 EFI_STATUS
 266 EFIAPI
 267 LibSetWakeupTime (
 268   IN BOOLEAN      Enabled,
 269   OUT EFI_TIME    *Time
 270   )
 271 {
 272   // Not a required feature
 273   return EFI_UNSUPPORTED;
 274 }
 275
 276 /**
 277   Fixup internal data so that EFI can be call in virtual mode.
 278   Call the passed in Child Notify event and convert any pointers in
 279   lib to virtual mode.
 280
 281   @param[in]    Event   The Event that is being processed
 282   @param[in]    Context Event Context
 283 **/
 284 VOID
 285 EFIAPI
 286 LibRtcVirtualNotifyEvent (
 287   IN EFI_EVENT        Event,
 288   IN VOID             *Context
 289   )
 290 {
 291   //
 292   // Only needed if you are going to support the OS calling RTC functions in virtual mode.
 293   // You will need to call EfiConvertPointer (). To convert any stored physical addresses
 294   // to virtual address. After the OS transitions to calling in virtual mode, all future
 295   // runtime calls will be made in virtual mode.
 296   //
 297   EfiConvertPointer (0x0, (VOID**)&mPL031RtcBase);
 298   return;
 299 }
 300
 301 /**
 302   This is the declaration of an EFI image entry point. This can be the entry point to an application
 303   written to this specification, an EFI boot service driver, or an EFI runtime driver.
 304
 305   @param  ImageHandle           Handle that identifies the loaded image.
 306   @param  SystemTable           System Table for this image.
 307
 308   @retval EFI_SUCCESS           The operation completed successfully.
 309
 310 **/
 311 EFI_STATUS
 312 EFIAPI
 313 LibRtcInitialize (
 314   IN EFI_HANDLE                            ImageHandle,
 315   IN EFI_SYSTEM_TABLE                      *SystemTable
 316   )
 317 {
 318   EFI_STATUS    Status;
 319   EFI_HANDLE    Handle;
 320
 321   // Initialize RTC Base Address
 322   mPL031RtcBase = PcdGet32 (PcdPL031RtcBase);
 323
 324   // Declare the controller as EFI_MEMORY_RUNTIME
 325   Status = gDS->AddMemorySpace (
 326                   EfiGcdMemoryTypeMemoryMappedIo,
 327                   mPL031RtcBase, SIZE_4KB,
 328                   EFI_MEMORY_UC | EFI_MEMORY_RUNTIME
 329                   );
 330   if (EFI_ERROR (Status)) {
 331     return Status;
 332   }
 333
 334   Status = gDS->SetMemorySpaceAttributes (mPL031RtcBase, SIZE_4KB, EFI_MEMORY_UC | EFI_MEMORY_RUNTIME);
 335   if (EFI_ERROR (Status)) {
 336     return Status;
 337   }
 338
 339   // Install the protocol
 340   Handle = NULL;
 341   Status = gBS->InstallMultipleProtocolInterfaces (
 342                   &Handle,
 343                   &gEfiRealTimeClockArchProtocolGuid,  NULL,
 344                   NULL
 345                  );
 346   ASSERT_EFI_ERROR (Status);
 347
 348   //
 349   // Register for the virtual address change event
 350   //
 351   Status = gBS->CreateEventEx (
 352                   EVT_NOTIFY_SIGNAL,
 353                   TPL_NOTIFY,
 354                   LibRtcVirtualNotifyEvent,
 355                   NULL,
 356                   &gEfiEventVirtualAddressChangeGuid,
 357                   &mRtcVirtualAddrChangeEvent
 358                   );
 359   ASSERT_EFI_ERROR (Status);
 360
 361   return Status;
 362 }