2 Implement EFI RealTimeClock runtime services via RTC Lib.
4 Currently this driver does not support runtime virtual calling.
6 Copyright (c) 2008 - 2010, Apple Inc. All rights reserved.<BR>
7 Copyright (c) 2011-2013, ARM Ltd. All rights reserved.<BR>
9 This program and the accompanying materials
10 are licensed and made available under the terms and conditions of the BSD License
11 which accompanies this distribution. The full text of the license may be found at
12 http://opensource.org/licenses/bsd-license.php
14 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
15 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
21 #include <Library/BaseLib.h>
22 #include <Library/DebugLib.h>
23 #include <Library/UefiLib.h>
24 #include <Library/IoLib.h>
25 #include <Library/RealTimeClockLib.h>
26 #include <Library/MemoryAllocationLib.h>
27 #include <Library/PcdLib.h>
28 #include <Library/ArmPlatformSysConfigLib.h>
29 #include <Library/UefiBootServicesTableLib.h>
30 #include <Library/UefiRuntimeServicesTableLib.h>
31 #include <Protocol/RealTimeClock.h>
32 #include <Guid/GlobalVariable.h>
33 #include <Drivers/PL031RealTimeClock.h>
35 #include <ArmPlatform.h>
37 CHAR16 mTimeZoneVariableName
[] = L
"PL031_TimeZone";
38 CHAR16 mDaylightVariableName
[] = L
"PL031_Daylight";
39 BOOLEAN mPL031Initialized
= FALSE
;
48 // Check if this is a PrimeCell Peripheral
49 if ( (MmioRead8 (PL031_RTC_PCELL_ID0
) != 0x0D)
50 || (MmioRead8 (PL031_RTC_PCELL_ID1
) != 0xF0)
51 || (MmioRead8 (PL031_RTC_PCELL_ID2
) != 0x05)
52 || (MmioRead8 (PL031_RTC_PCELL_ID3
) != 0xB1)) {
53 Status
= EFI_NOT_FOUND
;
57 // Check if this PrimeCell Peripheral is the PL031 Real Time Clock
58 if ( (MmioRead8 (PL031_RTC_PERIPH_ID0
) != 0x31)
59 || (MmioRead8 (PL031_RTC_PERIPH_ID1
) != 0x10)
60 || ((MmioRead8 (PL031_RTC_PERIPH_ID2
) & 0xF) != 0x04)
61 || (MmioRead8 (PL031_RTC_PERIPH_ID3
) != 0x00)) {
62 Status
= EFI_NOT_FOUND
;
79 // Prepare the hardware
80 Status
= IdentifyPL031();
81 if (EFI_ERROR (Status
)) {
85 // Ensure interrupts are masked. We do not want RTC interrupts in UEFI
86 if ((MmioRead32 (PL031_RTC_IMSC_IRQ_MASK_SET_CLEAR_REGISTER
) & PL031_SET_IRQ_MASK
) != PL031_SET_IRQ_MASK
) {
87 MmioOr32 (PL031_RTC_IMSC_IRQ_MASK_SET_CLEAR_REGISTER
, PL031_SET_IRQ_MASK
);
90 // Clear any existing interrupts
91 if ((MmioRead32 (PL031_RTC_RIS_RAW_IRQ_STATUS_REGISTER
) & PL031_IRQ_TRIGGERED
) == PL031_IRQ_TRIGGERED
) {
92 MmioOr32 (PL031_RTC_ICR_IRQ_CLEAR_REGISTER
, PL031_CLEAR_IRQ
);
95 // Start the clock counter
96 if ((MmioRead32 (PL031_RTC_CR_CONTROL_REGISTER
) & PL031_RTC_ENABLED
) != PL031_RTC_ENABLED
) {
97 MmioOr32 (PL031_RTC_CR_CONTROL_REGISTER
, PL031_RTC_ENABLED
);
100 mPL031Initialized
= TRUE
;
107 Converts Epoch seconds (elapsed since 1970 JANUARY 01, 00:00:00 UTC) to EFI_TIME
111 IN UINTN EpochSeconds
,
132 if (Time
->Daylight
== TRUE
) {
136 J
= (EpochSeconds
/ 86400) + 2440588;
140 c
= (((dg
/ 36524) + 1) * 3) / 4;
141 dc
= dg
- (c
* 36524);
144 a
= (((db
/ 365) + 1) * 3) / 4;
146 y
= (g
* 400) + (c
* 100) + (b
* 4) + a
;
147 m
= (((da
* 5) + 308) / 153) - 2;
148 d
= da
- (((m
+ 4) * 153) / 5) + 122;
150 Time
->Year
= y
- 4800 + ((m
+ 2) / 12);
151 Time
->Month
= ((m
+ 2) % 12) + 1;
154 ss
= EpochSeconds
% 60;
155 a
= (EpochSeconds
- ss
) / 60;
163 Time
->Nanosecond
= 0;
168 Converts EFI_TIME to Epoch seconds (elapsed since 1970 JANUARY 01, 00:00:00 UTC)
178 UINTN JulianDate
; // Absolute Julian Date representation of the supplied Time
179 UINTN EpochDays
; // Number of days elapsed since EPOCH_JULIAN_DAY
182 a
= (14 - Time
->Month
) / 12 ;
183 y
= Time
->Year
+ 4800 - a
;
184 m
= Time
->Month
+ (12*a
) - 3;
186 JulianDate
= Time
->Day
+ ((153*m
+ 2)/5) + (365*y
) + (y
/4) - (y
/100) + (y
/400) - 32045;
188 ASSERT(JulianDate
> EPOCH_JULIAN_DATE
);
189 EpochDays
= JulianDate
- EPOCH_JULIAN_DATE
;
191 EpochSeconds
= (EpochDays
* SEC_PER_DAY
) + ((UINTN
)Time
->Hour
* SEC_PER_HOUR
) + (Time
->Minute
* SEC_PER_MIN
) + Time
->Second
;
201 if (Time
->Year
% 4 == 0) {
202 if (Time
->Year
% 100 == 0) {
203 if (Time
->Year
% 400 == 0) {
221 INTN DayOfMonth
[12] = { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
224 Time
->Day
> DayOfMonth
[Time
->Month
- 1] ||
225 (Time
->Month
== 2 && (!IsLeapYear (Time
) && Time
->Day
> 28))
234 Returns the current time and date information, and the time-keeping capabilities
235 of the hardware platform.
237 @param Time A pointer to storage to receive a snapshot of the current time.
238 @param Capabilities An optional pointer to a buffer to receive the real time clock
239 device's capabilities.
241 @retval EFI_SUCCESS The operation completed successfully.
242 @retval EFI_INVALID_PARAMETER Time is NULL.
243 @retval EFI_DEVICE_ERROR The time could not be retrieved due to hardware error.
250 OUT EFI_TIME_CAPABILITIES
*Capabilities
253 EFI_STATUS Status
= EFI_SUCCESS
;
258 // Initialize the hardware if not already done
259 if (!mPL031Initialized
) {
260 Status
= InitializePL031 ();
261 if (EFI_ERROR (Status
)) {
266 // Snapshot the time as early in the function call as possible
267 // On some platforms we may have access to a battery backed up hardware clock.
268 // If such RTC exists try to use it first.
269 Status
= ArmPlatformSysConfigGet (SYS_CFG_RTC
, &EpochSeconds
);
270 if (Status
== EFI_UNSUPPORTED
) {
271 // Battery backed up hardware RTC does not exist, revert to PL031
272 EpochSeconds
= MmioRead32 (PL031_RTC_DR_DATA_REGISTER
);
273 Status
= EFI_SUCCESS
;
274 } else if (EFI_ERROR (Status
)) {
275 // Battery backed up hardware RTC exists but could not be read due to error. Abort.
278 // Battery backed up hardware RTC exists and we read the time correctly from it.
279 // Now sync the PL031 to the new time.
280 MmioWrite32 (PL031_RTC_LR_LOAD_REGISTER
, EpochSeconds
);
283 // Ensure Time is a valid pointer
285 Status
= EFI_INVALID_PARAMETER
;
289 // Get the current time zone information from non-volatile storage
290 TimeZone
= (INT16
*)GetVariable(mTimeZoneVariableName
, &gEfiGlobalVariableGuid
);
292 if (TimeZone
== NULL
) {
293 // The time zone variable does not exist in non-volatile storage, so create it.
294 Time
->TimeZone
= EFI_UNSPECIFIED_TIMEZONE
;
296 Status
= gRT
->SetVariable (
297 mTimeZoneVariableName
,
298 &gEfiGlobalVariableGuid
,
299 EFI_VARIABLE_NON_VOLATILE
| EFI_VARIABLE_BOOTSERVICE_ACCESS
| EFI_VARIABLE_RUNTIME_ACCESS
,
300 sizeof(Time
->TimeZone
),
303 if (EFI_ERROR (Status
)) {
304 DEBUG((EFI_D_ERROR
,"LibGetTime: ERROR: TimeZone\n"));
309 Time
->TimeZone
= *TimeZone
;
312 // Check TimeZone bounds: -1440 to 1440 or 2047
313 if (((Time
->TimeZone
< -1440) || (Time
->TimeZone
> 1440))
314 && (Time
->TimeZone
!= EFI_UNSPECIFIED_TIMEZONE
)) {
315 Time
->TimeZone
= EFI_UNSPECIFIED_TIMEZONE
;
318 // Adjust for the correct time zone
319 if (Time
->TimeZone
!= EFI_UNSPECIFIED_TIMEZONE
) {
320 EpochSeconds
+= Time
->TimeZone
* SEC_PER_MIN
;
324 // Get the current daylight information from non-volatile storage
325 Daylight
= (UINTN
*)GetVariable(mDaylightVariableName
, &gEfiGlobalVariableGuid
);
327 if (Daylight
== NULL
) {
328 // The daylight variable does not exist in non-volatile storage, so create it.
331 Status
= gRT
->SetVariable (
332 mDaylightVariableName
,
333 &gEfiGlobalVariableGuid
,
334 EFI_VARIABLE_NON_VOLATILE
| EFI_VARIABLE_BOOTSERVICE_ACCESS
| EFI_VARIABLE_RUNTIME_ACCESS
,
335 sizeof(Time
->Daylight
),
338 if (EFI_ERROR (Status
)) {
339 DEBUG((EFI_D_ERROR
,"LibGetTime: ERROR: Daylight\n"));
343 // Got the daylight information
344 Time
->Daylight
= *Daylight
;
347 // Adjust for the correct period
348 if ((Time
->Daylight
& EFI_TIME_IN_DAYLIGHT
) == EFI_TIME_IN_DAYLIGHT
) {
349 // Convert to adjusted time, i.e. spring forwards one hour
350 EpochSeconds
+= SEC_PER_HOUR
;
354 // Convert from internal 32-bit time to UEFI time
355 EpochToEfiTime (EpochSeconds
, Time
);
357 // Update the Capabilities info
358 if (Capabilities
!= NULL
) {
359 // PL031 runs at frequency 1Hz
360 Capabilities
->Resolution
= PL031_COUNTS_PER_SECOND
;
361 // Accuracy in ppm multiplied by 1,000,000, e.g. for 50ppm set 50,000,000
362 Capabilities
->Accuracy
= (UINT32
)PcdGet32 (PcdPL031RtcPpmAccuracy
);
363 // FALSE: Setting the time does not clear the values below the resolution level
364 Capabilities
->SetsToZero
= FALSE
;
373 Sets the current local time and date information.
375 @param Time A pointer to the current time.
377 @retval EFI_SUCCESS The operation completed successfully.
378 @retval EFI_INVALID_PARAMETER A time field is out of range.
379 @retval EFI_DEVICE_ERROR The time could not be set due due to hardware error.
391 // Because the PL031 is a 32-bit counter counting seconds,
392 // the maximum time span is just over 136 years.
393 // Time is stored in Unix Epoch format, so it starts in 1970,
394 // Therefore it can not exceed the year 2106.
395 // This is not a problem for UEFI, as the current spec limits the years
396 // to the range 1998 .. 2011
398 // Check the input parameters' range.
399 if ((Time
->Year
< 1998) ||
400 (Time
->Year
> 2099) ||
401 (Time
->Month
< 1 ) ||
402 (Time
->Month
> 12 ) ||
403 (!DayValid (Time
) ) ||
404 (Time
->Hour
> 23 ) ||
405 (Time
->Minute
> 59 ) ||
406 (Time
->Second
> 59 ) ||
407 (Time
->Nanosecond
> 999999999) ||
408 (!((Time
->TimeZone
== EFI_UNSPECIFIED_TIMEZONE
) || ((Time
->TimeZone
>= -1440) && (Time
->TimeZone
<= 1440)))) ||
409 (Time
->Daylight
& (~(EFI_TIME_ADJUST_DAYLIGHT
| EFI_TIME_IN_DAYLIGHT
)))
411 Status
= EFI_INVALID_PARAMETER
;
415 // Initialize the hardware if not already done
416 if (!mPL031Initialized
) {
417 Status
= InitializePL031 ();
418 if (EFI_ERROR (Status
)) {
423 EpochSeconds
= EfiTimeToEpoch (Time
);
425 // Adjust for the correct time zone, i.e. convert to UTC time zone
426 if (Time
->TimeZone
!= EFI_UNSPECIFIED_TIMEZONE
) {
427 EpochSeconds
-= Time
->TimeZone
* SEC_PER_MIN
;
430 // TODO: Automatic Daylight activation
432 // Adjust for the correct period
433 if ((Time
->Daylight
& EFI_TIME_IN_DAYLIGHT
) == EFI_TIME_IN_DAYLIGHT
) {
434 // Convert to un-adjusted time, i.e. fall back one hour
435 EpochSeconds
-= SEC_PER_HOUR
;
438 // On some platforms we may have access to a battery backed up hardware clock.
440 // If such RTC exists then it must be updated first, before the PL031,
441 // to minimise any time drift. This is important because the battery backed-up
442 // RTC maintains the master time for the platform across reboots.
444 // If such RTC does not exist then the following function returns UNSUPPORTED.
445 Status
= ArmPlatformSysConfigSet (SYS_CFG_RTC
, EpochSeconds
);
446 if ((EFI_ERROR (Status
)) && (Status
!= EFI_UNSUPPORTED
)){
447 // Any status message except SUCCESS and UNSUPPORTED indicates a hardware failure.
453 MmioWrite32 (PL031_RTC_LR_LOAD_REGISTER
, EpochSeconds
);
455 // The accesses to Variable Services can be very slow, because we may be writing to Flash.
456 // Do this after having set the RTC.
458 // Save the current time zone information into non-volatile storage
459 Status
= gRT
->SetVariable (
460 mTimeZoneVariableName
,
461 &gEfiGlobalVariableGuid
,
462 EFI_VARIABLE_NON_VOLATILE
| EFI_VARIABLE_BOOTSERVICE_ACCESS
| EFI_VARIABLE_RUNTIME_ACCESS
,
463 sizeof(Time
->TimeZone
),
466 if (EFI_ERROR (Status
)) {
467 DEBUG((EFI_D_ERROR
,"LibSetTime: ERROR: TimeZone\n"));
471 // Save the current daylight information into non-volatile storage
472 Status
= gRT
->SetVariable (
473 mDaylightVariableName
,
474 &gEfiGlobalVariableGuid
,
475 EFI_VARIABLE_NON_VOLATILE
| EFI_VARIABLE_BOOTSERVICE_ACCESS
| EFI_VARIABLE_RUNTIME_ACCESS
,
476 sizeof(Time
->Daylight
),
479 if (EFI_ERROR (Status
)) {
480 DEBUG((EFI_D_ERROR
,"LibSetTime: ERROR: Daylight\n"));
490 Returns the current wakeup alarm clock setting.
492 @param Enabled Indicates if the alarm is currently enabled or disabled.
493 @param Pending Indicates if the alarm signal is pending and requires acknowledgement.
494 @param Time The current alarm setting.
496 @retval EFI_SUCCESS The alarm settings were returned.
497 @retval EFI_INVALID_PARAMETER Any parameter is NULL.
498 @retval EFI_DEVICE_ERROR The wakeup time could not be retrieved due to a hardware error.
504 OUT BOOLEAN
*Enabled
,
505 OUT BOOLEAN
*Pending
,
509 // Not a required feature
510 return EFI_UNSUPPORTED
;
515 Sets the system wakeup alarm clock time.
517 @param Enabled Enable or disable the wakeup alarm.
518 @param Time If Enable is TRUE, the time to set the wakeup alarm for.
520 @retval EFI_SUCCESS If Enable is TRUE, then the wakeup alarm was enabled. If
521 Enable is FALSE, then the wakeup alarm was disabled.
522 @retval EFI_INVALID_PARAMETER A time field is out of range.
523 @retval EFI_DEVICE_ERROR The wakeup time could not be set due to a hardware error.
524 @retval EFI_UNSUPPORTED A wakeup timer is not supported on this platform.
534 // Not a required feature
535 return EFI_UNSUPPORTED
;
541 This is the declaration of an EFI image entry point. This can be the entry point to an application
542 written to this specification, an EFI boot service driver, or an EFI runtime driver.
544 @param ImageHandle Handle that identifies the loaded image.
545 @param SystemTable System Table for this image.
547 @retval EFI_SUCCESS The operation completed successfully.
553 IN EFI_HANDLE ImageHandle
,
554 IN EFI_SYSTEM_TABLE
*SystemTable
560 // Setup the setters and getters
561 gRT
->GetTime
= LibGetTime
;
562 gRT
->SetTime
= LibSetTime
;
563 gRT
->GetWakeupTime
= LibGetWakeupTime
;
564 gRT
->SetWakeupTime
= LibSetWakeupTime
;
566 // Install the protocol
568 Status
= gBS
->InstallMultipleProtocolInterfaces (
570 &gEfiRealTimeClockArchProtocolGuid
, NULL
,
579 Fixup internal data so that EFI can be call in virtual mode.
580 Call the passed in Child Notify event and convert any pointers in
583 @param[in] Event The Event that is being processed
584 @param[in] Context Event Context
588 LibRtcVirtualNotifyEvent (
594 // Only needed if you are going to support the OS calling RTC functions in virtual mode.
595 // You will need to call EfiConvertPointer (). To convert any stored physical addresses
596 // to virtual address. After the OS transitions to calling in virtual mode, all future
597 // runtime calls will be made in virtual mode.