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