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 STATIC CONST CHAR16 mTimeZoneVariableName
[] = L
"PL031RtcTimeZone";
38 STATIC CONST CHAR16 mDaylightVariableName
[] = L
"PL031RtcDaylight";
39 STATIC 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 J
= (EpochSeconds
/ 86400) + 2440588;
136 c
= (((dg
/ 36524) + 1) * 3) / 4;
137 dc
= dg
- (c
* 36524);
140 a
= (((db
/ 365) + 1) * 3) / 4;
142 y
= (g
* 400) + (c
* 100) + (b
* 4) + a
;
143 m
= (((da
* 5) + 308) / 153) - 2;
144 d
= da
- (((m
+ 4) * 153) / 5) + 122;
146 Time
->Year
= y
- 4800 + ((m
+ 2) / 12);
147 Time
->Month
= ((m
+ 2) % 12) + 1;
150 ss
= EpochSeconds
% 60;
151 a
= (EpochSeconds
- ss
) / 60;
159 Time
->Nanosecond
= 0;
164 Converts EFI_TIME to Epoch seconds (elapsed since 1970 JANUARY 01, 00:00:00 UTC)
174 UINTN JulianDate
; // Absolute Julian Date representation of the supplied Time
175 UINTN EpochDays
; // Number of days elapsed since EPOCH_JULIAN_DAY
178 a
= (14 - Time
->Month
) / 12 ;
179 y
= Time
->Year
+ 4800 - a
;
180 m
= Time
->Month
+ (12*a
) - 3;
182 JulianDate
= Time
->Day
+ ((153*m
+ 2)/5) + (365*y
) + (y
/4) - (y
/100) + (y
/400) - 32045;
184 ASSERT(JulianDate
> EPOCH_JULIAN_DATE
);
185 EpochDays
= JulianDate
- EPOCH_JULIAN_DATE
;
187 EpochSeconds
= (EpochDays
* SEC_PER_DAY
) + ((UINTN
)Time
->Hour
* SEC_PER_HOUR
) + (Time
->Minute
* SEC_PER_MIN
) + Time
->Second
;
197 if (Time
->Year
% 4 == 0) {
198 if (Time
->Year
% 100 == 0) {
199 if (Time
->Year
% 400 == 0) {
217 INTN DayOfMonth
[12] = { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
220 Time
->Day
> DayOfMonth
[Time
->Month
- 1] ||
221 (Time
->Month
== 2 && (!IsLeapYear (Time
) && Time
->Day
> 28))
230 Returns the current time and date information, and the time-keeping capabilities
231 of the hardware platform.
233 @param Time A pointer to storage to receive a snapshot of the current time.
234 @param Capabilities An optional pointer to a buffer to receive the real time clock
235 device's capabilities.
237 @retval EFI_SUCCESS The operation completed successfully.
238 @retval EFI_INVALID_PARAMETER Time is NULL.
239 @retval EFI_DEVICE_ERROR The time could not be retrieved due to hardware error.
240 @retval EFI_SECURITY_VIOLATION The time could not be retrieved due to an authentication failure.
247 OUT EFI_TIME_CAPABILITIES
*Capabilities
250 EFI_STATUS Status
= EFI_SUCCESS
;
256 // Initialize the hardware if not already done
257 if (!mPL031Initialized
) {
258 Status
= InitializePL031 ();
259 if (EFI_ERROR (Status
)) {
264 // Snapshot the time as early in the function call as possible
265 // On some platforms we may have access to a battery backed up hardware clock.
266 // If such RTC exists try to use it first.
267 Status
= ArmPlatformSysConfigGet (SYS_CFG_RTC
, &EpochSeconds
);
268 if (Status
== EFI_UNSUPPORTED
) {
269 // Battery backed up hardware RTC does not exist, revert to PL031
270 EpochSeconds
= MmioRead32 (PL031_RTC_DR_DATA_REGISTER
);
271 Status
= EFI_SUCCESS
;
272 } else if (EFI_ERROR (Status
)) {
273 // Battery backed up hardware RTC exists but could not be read due to error. Abort.
276 // Battery backed up hardware RTC exists and we read the time correctly from it.
277 // Now sync the PL031 to the new time.
278 MmioWrite32 (PL031_RTC_LR_LOAD_REGISTER
, EpochSeconds
);
281 // Ensure Time is a valid pointer
283 Status
= EFI_INVALID_PARAMETER
;
287 // Get the current time zone information from non-volatile storage
288 Size
= sizeof (TimeZone
);
289 Status
= gRT
->GetVariable (
290 (CHAR16
*)mTimeZoneVariableName
,
297 if (EFI_ERROR (Status
)) {
298 ASSERT(Status
!= EFI_INVALID_PARAMETER
);
299 ASSERT(Status
!= EFI_BUFFER_TOO_SMALL
);
301 if (Status
!= EFI_NOT_FOUND
)
304 // The time zone variable does not exist in non-volatile storage, so create it.
305 Time
->TimeZone
= EFI_UNSPECIFIED_TIMEZONE
;
307 Status
= gRT
->SetVariable (
308 (CHAR16
*)mTimeZoneVariableName
,
310 EFI_VARIABLE_NON_VOLATILE
| EFI_VARIABLE_BOOTSERVICE_ACCESS
| EFI_VARIABLE_RUNTIME_ACCESS
,
312 (VOID
*)&(Time
->TimeZone
)
314 if (EFI_ERROR (Status
)) {
317 "LibGetTime: Failed to save %s variable to non-volatile storage, Status = %r\n",
318 mTimeZoneVariableName
,
325 Time
->TimeZone
= TimeZone
;
327 // Check TimeZone bounds: -1440 to 1440 or 2047
328 if (((Time
->TimeZone
< -1440) || (Time
->TimeZone
> 1440))
329 && (Time
->TimeZone
!= EFI_UNSPECIFIED_TIMEZONE
)) {
330 Time
->TimeZone
= EFI_UNSPECIFIED_TIMEZONE
;
333 // Adjust for the correct time zone
334 if (Time
->TimeZone
!= EFI_UNSPECIFIED_TIMEZONE
) {
335 EpochSeconds
+= Time
->TimeZone
* SEC_PER_MIN
;
339 // Get the current daylight information from non-volatile storage
340 Size
= sizeof (Daylight
);
341 Status
= gRT
->GetVariable (
342 (CHAR16
*)mDaylightVariableName
,
349 if (EFI_ERROR (Status
)) {
350 ASSERT(Status
!= EFI_INVALID_PARAMETER
);
351 ASSERT(Status
!= EFI_BUFFER_TOO_SMALL
);
353 if (Status
!= EFI_NOT_FOUND
)
356 // The daylight variable does not exist in non-volatile storage, so create it.
359 Status
= gRT
->SetVariable (
360 (CHAR16
*)mDaylightVariableName
,
362 EFI_VARIABLE_NON_VOLATILE
| EFI_VARIABLE_BOOTSERVICE_ACCESS
| EFI_VARIABLE_RUNTIME_ACCESS
,
364 (VOID
*)&(Time
->Daylight
)
366 if (EFI_ERROR (Status
)) {
369 "LibGetTime: Failed to save %s variable to non-volatile storage, Status = %r\n",
370 mDaylightVariableName
,
376 // Got the daylight information
377 Time
->Daylight
= Daylight
;
379 // Adjust for the correct period
380 if ((Time
->Daylight
& EFI_TIME_IN_DAYLIGHT
) == EFI_TIME_IN_DAYLIGHT
) {
381 // Convert to adjusted time, i.e. spring forwards one hour
382 EpochSeconds
+= SEC_PER_HOUR
;
386 // Convert from internal 32-bit time to UEFI time
387 EpochToEfiTime (EpochSeconds
, Time
);
389 // Update the Capabilities info
390 if (Capabilities
!= NULL
) {
391 // PL031 runs at frequency 1Hz
392 Capabilities
->Resolution
= PL031_COUNTS_PER_SECOND
;
393 // Accuracy in ppm multiplied by 1,000,000, e.g. for 50ppm set 50,000,000
394 Capabilities
->Accuracy
= (UINT32
)PcdGet32 (PcdPL031RtcPpmAccuracy
);
395 // FALSE: Setting the time does not clear the values below the resolution level
396 Capabilities
->SetsToZero
= FALSE
;
405 Sets the current local time and date information.
407 @param Time A pointer to the current time.
409 @retval EFI_SUCCESS The operation completed successfully.
410 @retval EFI_INVALID_PARAMETER A time field is out of range.
411 @retval EFI_DEVICE_ERROR The time could not be set due due to hardware error.
423 // Because the PL031 is a 32-bit counter counting seconds,
424 // the maximum time span is just over 136 years.
425 // Time is stored in Unix Epoch format, so it starts in 1970,
426 // Therefore it can not exceed the year 2106.
427 // This is not a problem for UEFI, as the current spec limits the years
428 // to the range 1998 .. 2011
430 // Check the input parameters' range.
431 if ((Time
->Year
< 1998) ||
432 (Time
->Year
> 2099) ||
433 (Time
->Month
< 1 ) ||
434 (Time
->Month
> 12 ) ||
435 (!DayValid (Time
) ) ||
436 (Time
->Hour
> 23 ) ||
437 (Time
->Minute
> 59 ) ||
438 (Time
->Second
> 59 ) ||
439 (Time
->Nanosecond
> 999999999) ||
440 (!((Time
->TimeZone
== EFI_UNSPECIFIED_TIMEZONE
) || ((Time
->TimeZone
>= -1440) && (Time
->TimeZone
<= 1440)))) ||
441 (Time
->Daylight
& (~(EFI_TIME_ADJUST_DAYLIGHT
| EFI_TIME_IN_DAYLIGHT
)))
443 Status
= EFI_INVALID_PARAMETER
;
447 // Initialize the hardware if not already done
448 if (!mPL031Initialized
) {
449 Status
= InitializePL031 ();
450 if (EFI_ERROR (Status
)) {
455 EpochSeconds
= EfiTimeToEpoch (Time
);
457 // Adjust for the correct time zone, i.e. convert to UTC time zone
458 if (Time
->TimeZone
!= EFI_UNSPECIFIED_TIMEZONE
) {
459 EpochSeconds
-= Time
->TimeZone
* SEC_PER_MIN
;
462 // TODO: Automatic Daylight activation
464 // Adjust for the correct period
465 if ((Time
->Daylight
& EFI_TIME_IN_DAYLIGHT
) == EFI_TIME_IN_DAYLIGHT
) {
466 // Convert to un-adjusted time, i.e. fall back one hour
467 EpochSeconds
-= SEC_PER_HOUR
;
470 // On some platforms we may have access to a battery backed up hardware clock.
472 // If such RTC exists then it must be updated first, before the PL031,
473 // to minimise any time drift. This is important because the battery backed-up
474 // RTC maintains the master time for the platform across reboots.
476 // If such RTC does not exist then the following function returns UNSUPPORTED.
477 Status
= ArmPlatformSysConfigSet (SYS_CFG_RTC
, EpochSeconds
);
478 if ((EFI_ERROR (Status
)) && (Status
!= EFI_UNSUPPORTED
)){
479 // Any status message except SUCCESS and UNSUPPORTED indicates a hardware failure.
485 MmioWrite32 (PL031_RTC_LR_LOAD_REGISTER
, EpochSeconds
);
487 // The accesses to Variable Services can be very slow, because we may be writing to Flash.
488 // Do this after having set the RTC.
490 // Save the current time zone information into non-volatile storage
491 Status
= gRT
->SetVariable (
492 (CHAR16
*)mTimeZoneVariableName
,
494 EFI_VARIABLE_NON_VOLATILE
| EFI_VARIABLE_BOOTSERVICE_ACCESS
| EFI_VARIABLE_RUNTIME_ACCESS
,
495 sizeof (Time
->TimeZone
),
496 (VOID
*)&(Time
->TimeZone
)
498 if (EFI_ERROR (Status
)) {
501 "LibSetTime: Failed to save %s variable to non-volatile storage, Status = %r\n",
502 mTimeZoneVariableName
,
508 // Save the current daylight information into non-volatile storage
509 Status
= gRT
->SetVariable (
510 (CHAR16
*)mDaylightVariableName
,
512 EFI_VARIABLE_NON_VOLATILE
| EFI_VARIABLE_BOOTSERVICE_ACCESS
| EFI_VARIABLE_RUNTIME_ACCESS
,
513 sizeof(Time
->Daylight
),
514 (VOID
*)&(Time
->Daylight
)
516 if (EFI_ERROR (Status
)) {
519 "LibSetTime: Failed to save %s variable to non-volatile storage, Status = %r\n",
520 mDaylightVariableName
,
532 Returns the current wakeup alarm clock setting.
534 @param Enabled Indicates if the alarm is currently enabled or disabled.
535 @param Pending Indicates if the alarm signal is pending and requires acknowledgement.
536 @param Time The current alarm setting.
538 @retval EFI_SUCCESS The alarm settings were returned.
539 @retval EFI_INVALID_PARAMETER Any parameter is NULL.
540 @retval EFI_DEVICE_ERROR The wakeup time could not be retrieved due to a hardware error.
546 OUT BOOLEAN
*Enabled
,
547 OUT BOOLEAN
*Pending
,
551 // Not a required feature
552 return EFI_UNSUPPORTED
;
557 Sets the system wakeup alarm clock time.
559 @param Enabled Enable or disable the wakeup alarm.
560 @param Time If Enable is TRUE, the time to set the wakeup alarm for.
562 @retval EFI_SUCCESS If Enable is TRUE, then the wakeup alarm was enabled. If
563 Enable is FALSE, then the wakeup alarm was disabled.
564 @retval EFI_INVALID_PARAMETER A time field is out of range.
565 @retval EFI_DEVICE_ERROR The wakeup time could not be set due to a hardware error.
566 @retval EFI_UNSUPPORTED A wakeup timer is not supported on this platform.
576 // Not a required feature
577 return EFI_UNSUPPORTED
;
583 This is the declaration of an EFI image entry point. This can be the entry point to an application
584 written to this specification, an EFI boot service driver, or an EFI runtime driver.
586 @param ImageHandle Handle that identifies the loaded image.
587 @param SystemTable System Table for this image.
589 @retval EFI_SUCCESS The operation completed successfully.
595 IN EFI_HANDLE ImageHandle
,
596 IN EFI_SYSTEM_TABLE
*SystemTable
602 // Setup the setters and getters
603 gRT
->GetTime
= LibGetTime
;
604 gRT
->SetTime
= LibSetTime
;
605 gRT
->GetWakeupTime
= LibGetWakeupTime
;
606 gRT
->SetWakeupTime
= LibSetWakeupTime
;
608 // Install the protocol
610 Status
= gBS
->InstallMultipleProtocolInterfaces (
612 &gEfiRealTimeClockArchProtocolGuid
, NULL
,
621 Fixup internal data so that EFI can be call in virtual mode.
622 Call the passed in Child Notify event and convert any pointers in
625 @param[in] Event The Event that is being processed
626 @param[in] Context Event Context
630 LibRtcVirtualNotifyEvent (
636 // Only needed if you are going to support the OS calling RTC functions in virtual mode.
637 // You will need to call EfiConvertPointer (). To convert any stored physical addresses
638 // to virtual address. After the OS transitions to calling in virtual mode, all future
639 // runtime calls will be made in virtual mode.