#include "PcRtc.h"

Functions
INTN	CompareHMS (IN EFI_TIME From, IN EFI_TIME To)

BOOLEAN	IsWithinOneDay (IN EFI_TIME From, IN EFI_TIME To)

STATIC UINT8	IoRtcRead (IN UINTN Address)

STATIC VOID	IoRtcWrite (IN UINTN Address, IN UINT8 Data)

STATIC UINT8	MmioRtcRead (IN UINTN Address)

STATIC VOID	MmioRtcWrite (IN UINTN Address, IN UINT8 Data)

STATIC UINT8	RtcRead (IN UINTN Address)

STATIC VOID	RtcWrite (IN UINTN Address, IN UINT8 Data)

EFI_STATUS	PcRtcSetTimeZone (IN INT16 TimeZone, IN UINT8 Daylight, IN PC_RTC_MODULE_GLOBALS *Global)

EFI_STATUS	PcRtcInit (IN PC_RTC_MODULE_GLOBALS *Global)

EFI_STATUS	PcRtcGetTime (OUT EFI_TIME Time, OUT EFI_TIME_CAPABILITIES Capabilities OPTIONAL, IN PC_RTC_MODULE_GLOBALS *Global)

EFI_STATUS	PcRtcSetTime (IN EFI_TIME Time, IN PC_RTC_MODULE_GLOBALS Global)

EFI_STATUS	PcRtcGetWakeupTime (OUT BOOLEAN Enabled, OUT BOOLEAN Pending, OUT EFI_TIME Time, IN PC_RTC_MODULE_GLOBALS Global)

EFI_STATUS	PcRtcSetWakeupTime (IN BOOLEAN Enable, IN EFI_TIME Time OPTIONAL, IN PC_RTC_MODULE_GLOBALS Global)

UINT8	CheckAndConvertBcd8ToDecimal8 (IN UINT8 Value)

EFI_STATUS	ConvertRtcTimeToEfiTime (IN OUT EFI_TIME *Time, IN RTC_REGISTER_B RegisterB)

EFI_STATUS	RtcWaitToUpdate (UINTN Timeout)

EFI_STATUS	RtcTimeFieldsValid (IN EFI_TIME *Time)

BOOLEAN	DayValid (IN EFI_TIME *Time)

BOOLEAN	IsLeapYear (IN EFI_TIME *Time)

VOID	ConvertEfiTimeToRtcTime (IN OUT EFI_TIME *Time, IN RTC_REGISTER_B RegisterB)

UINT8	GetCenturyRtcAddress (VOID)

VOID EFIAPI	PcRtcAcpiTableChangeCallback (IN EFI_EVENT Event, IN VOID *Context)

Variables
UINTN	mRtcIndexRegister

UINTN	mRtcTargetRegister

UINT16	mRtcDefaultYear

UINT16	mMinimalValidYear

UINT16	mMaximalValidYear

UINTN	mDayOfMonth [] = { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }

CHAR16	mTimeZoneVariableName [] = L"RTC"

Detailed Description

RTC Architectural Protocol GUID as defined in DxeCis 0.96.

SPDX-License-Identifier: BSD-2-Clause-Patent

Definition in file PcRtc.c.

Function Documentation

◆ CheckAndConvertBcd8ToDecimal8()

UINT8 CheckAndConvertBcd8ToDecimal8 ( IN UINT8 Value )

Checks an 8-bit BCD value, and converts to an 8-bit value if valid.

This function checks the 8-bit BCD value specified by Value. If valid, the function converts it to an 8-bit value and returns it. Otherwise, return 0xff.

Parameters

Value The 8-bit BCD value to check and convert

Returns: The 8-bit value converted. Or 0xff if Value is invalid.

Definition at line 1022 of file PcRtc.c.

◆ CompareHMS()

INTN CompareHMS	(	IN EFI_TIME *	From,
		IN EFI_TIME *	To
	)

Compare the Hour, Minute and Second of the From time and the To time.

Only compare H/M/S in EFI_TIME and ignore other fields here.

Parameters

From	the first time
To	the second time

Returns: >0 The H/M/S of the From time is later than those of To time; ==0 The H/M/S of the From time is same as those of To time; <0 The H/M/S of the From time is earlier than those of To time

Definition at line 1318 of file PcRtc.c.

◆ ConvertEfiTimeToRtcTime()

VOID ConvertEfiTimeToRtcTime	(	IN OUT EFI_TIME *	Time,
		IN RTC_REGISTER_B	RegisterB
	)

Converts time from EFI_TIME format defined by UEFI spec to RTC format.

This function converts time from EFI_TIME format defined by UEFI spec to RTC format. If data mode of RTC is BCD, then converts EFI_TIME to it. If RTC is in 12-hour format, then converts EFI_TIME to it.

Parameters

Time	On input, the time data read from UEFI to convert On output, the time converted to RTC format
RegisterB	Value of Register B of RTC, indicating data mode

Definition at line 1260 of file PcRtc.c.

◆ ConvertRtcTimeToEfiTime()

EFI_STATUS ConvertRtcTimeToEfiTime	(	IN OUT EFI_TIME *	Time,
		IN RTC_REGISTER_B	RegisterB
	)

Converts time read from RTC to EFI_TIME format defined by UEFI spec.

This function converts raw time data read from RTC to the EFI_TIME format defined by UEFI spec. If data mode of RTC is BCD, then converts it to decimal, If RTC is in 12-hour format, then converts it to 24-hour format.

Parameters

Time	On input, the time data read from RTC to convert On output, the time converted to UEFI format
RegisterB	Value of Register B of RTC, indicating data mode and hour format.

Return values

EFI_INVALID_PARAMETER	Parameters passed in are invalid.
EFI_SUCCESS	Convert RTC time to EFI time successfully.

Definition at line 1051 of file PcRtc.c.

◆ DayValid()

BOOLEAN DayValid ( IN EFI_TIME * Time )

See if field Day of an EFI_TIME is correct.

Parameters

Time	Its Day field is to be checked.

Return values

TRUE	Day field of Time is correct.
FALSE	Day field of Time is NOT correct.

Definition at line 1200 of file PcRtc.c.

◆ GetCenturyRtcAddress()

UINT8 GetCenturyRtcAddress ( VOID )

Get the century RTC address from the ACPI FADT table.

Returns: The century RTC address or 0 if not found.

Definition at line 1404 of file PcRtc.c.

◆ IoRtcRead()

STATIC UINT8 IoRtcRead ( IN UINTN Address )

Read RTC content through its registers using IO access.

Parameters

Address Address offset of RTC. It is recommended to use macros such as RTC_ADDRESS_SECONDS.

Returns: The data of UINT8 type read from RTC.

Definition at line 72 of file PcRtc.c.

◆ IoRtcWrite()

STATIC VOID IoRtcWrite	(	IN UINTN	Address,
		IN UINT8	Data
	)

Write RTC through its registers using IO access.

Parameters

Address	Address offset of RTC. It is recommended to use macros such as RTC_ADDRESS_SECONDS.
Data	The content you want to write into RTC.

Definition at line 93 of file PcRtc.c.

◆ IsLeapYear()

BOOLEAN IsLeapYear ( IN EFI_TIME * Time )

Check if it is a leap year.

Parameters

Time	The time to be checked.

Return values

TRUE	It is a leap year.
FALSE	It is NOT a leap year.

Definition at line 1229 of file PcRtc.c.

◆ IsWithinOneDay()

BOOLEAN IsWithinOneDay	(	IN EFI_TIME *	From,
		IN EFI_TIME *	To
	)

To check if second date is later than first date within 24 hours.

Parameters

From	the first date
To	the second date

Return values

TRUE	From is previous to To within 24 hours.
FALSE	From is later, or it is previous to To more than 24 hours.

Definition at line 1345 of file PcRtc.c.

◆ MmioRtcRead()

STATIC UINT8 MmioRtcRead ( IN UINTN Address )

Read RTC content through its registers using MMIO access.

Parameters

Address Address offset of RTC. It is recommended to use macros such as RTC_ADDRESS_SECONDS.

Returns: The data of UINT8 type read from RTC.

Definition at line 115 of file PcRtc.c.

◆ MmioRtcWrite()

STATIC VOID MmioRtcWrite	(	IN UINTN	Address,
		IN UINT8	Data
	)

Write RTC through its registers using MMIO access.

Parameters

Address	Address offset of RTC. It is recommended to use macros such as RTC_ADDRESS_SECONDS.
Data	The content you want to write into RTC.

Definition at line 136 of file PcRtc.c.

◆ PcRtcAcpiTableChangeCallback()

VOID EFIAPI PcRtcAcpiTableChangeCallback	(	IN EFI_EVENT	Event,
		IN VOID *	Context
	)

Notification function of ACPI Table change.

This is a notification function registered on ACPI Table change event. It saves the Century address stored in ACPI FADT table.

Parameters

Event	Event whose notification function is being invoked.
Context	Pointer to the notification function's context.

Definition at line 1436 of file PcRtc.c.

◆ PcRtcGetTime()

EFI_STATUS PcRtcGetTime	(	OUT EFI_TIME *	Time,
		OUT EFI_TIME_CAPABILITIES *Capabilities	OPTIONAL,
		IN PC_RTC_MODULE_GLOBALS *	Global
	)

Returns the current time and date information, and the time-keeping capabilities of the hardware platform.

Parameters

Time	A pointer to storage to receive a snapshot of the current time.
Capabilities	An optional pointer to a buffer to receive the real time clock device's capabilities.
Global	For global use inside this module.

Return values

EFI_SUCCESS	The operation completed successfully.
EFI_INVALID_PARAMETER	Time is NULL.
EFI_DEVICE_ERROR	The time could not be retrieved due to hardware error.

Definition at line 527 of file PcRtc.c.

◆ PcRtcGetWakeupTime()

EFI_STATUS PcRtcGetWakeupTime	(	OUT BOOLEAN *	Enabled,
		OUT BOOLEAN *	Pending,
		OUT EFI_TIME *	Time,
		IN PC_RTC_MODULE_GLOBALS *	Global
	)

Returns the current wakeup alarm clock setting.

Parameters

Enabled	Indicates if the alarm is currently enabled or disabled.
Pending	Indicates if the alarm signal is pending and requires acknowledgment.
Time	The current alarm setting.
Global	For global use inside this module.

Return values

EFI_SUCCESS	The alarm settings were returned.
EFI_INVALID_PARAMETER	Enabled is NULL.
EFI_INVALID_PARAMETER	Pending is NULL.
EFI_INVALID_PARAMETER	Time is NULL.
EFI_DEVICE_ERROR	The wakeup time could not be retrieved due to a hardware error.
EFI_UNSUPPORTED	A wakeup timer is not supported on this platform.

Definition at line 750 of file PcRtc.c.

◆ PcRtcInit()

EFI_STATUS PcRtcInit ( IN PC_RTC_MODULE_GLOBALS * Global )

Initialize RTC.

Parameters

Global For global use inside this module.

Return values

EFI_DEVICE_ERROR	Initialization failed due to device error.
EFI_SUCCESS	Initialization successful.

Definition at line 262 of file PcRtc.c.

◆ PcRtcSetTime()

EFI_STATUS PcRtcSetTime	(	IN EFI_TIME *	Time,
		IN PC_RTC_MODULE_GLOBALS *	Global
	)

Sets the current local time and date information.

Parameters

Time	A pointer to the current time.
Global	For global use inside this module.

Return values

EFI_SUCCESS	The operation completed successfully.
EFI_INVALID_PARAMETER	A time field is out of range.
EFI_DEVICE_ERROR	The time could not be set due due to hardware error.

Definition at line 632 of file PcRtc.c.

◆ PcRtcSetTimeZone()

EFI_STATUS PcRtcSetTimeZone	(	IN INT16	TimeZone,
		IN UINT8	Daylight,
		IN PC_RTC_MODULE_GLOBALS *	Global
	)

Sets the current local timezone & daylight information.

Parameters

TimeZone	Timezone info.
Daylight	Daylight info.
Global	For global use inside this module.

Return values

EFI_SUCCESS	The operation completed successfully.
EFI_DEVICE_ERROR	The variable could not be set due due to hardware error.

Definition at line 203 of file PcRtc.c.

◆ PcRtcSetWakeupTime()

EFI_STATUS PcRtcSetWakeupTime	(	IN BOOLEAN	Enable,
		IN EFI_TIME *Time	OPTIONAL,
		IN PC_RTC_MODULE_GLOBALS *	Global
	)

Sets the system wakeup alarm clock time.

Parameters

Enabled	Enable or disable the wakeup alarm.
Time	If Enable is TRUE, the time to set the wakeup alarm for. If Enable is FALSE, then this parameter is optional, and may be NULL.
Global	For global use inside this module.

Return values

EFI_SUCCESS	If Enable is TRUE, then the wakeup alarm was enabled. If Enable is FALSE, then the wakeup alarm was disabled.
EFI_INVALID_PARAMETER	A time field is out of range.
EFI_DEVICE_ERROR	The wakeup time could not be set due to a hardware error.
EFI_UNSUPPORTED	A wakeup timer is not supported on this platform.

Definition at line 868 of file PcRtc.c.

◆ RtcRead()

STATIC UINT8 RtcRead ( IN UINTN Address )

Read RTC content through its registers.

Parameters

Address Address offset of RTC. It is recommended to use macros such as RTC_ADDRESS_SECONDS.

Returns: The data of UINT8 type read from RTC.

Definition at line 158 of file PcRtc.c.

◆ RtcTimeFieldsValid()

EFI_STATUS RtcTimeFieldsValid ( IN EFI_TIME * Time )

See if all fields of a variable of EFI_TIME type is correct.

Parameters

Time	The time to be checked.

Return values

EFI_INVALID_PARAMETER	Some fields of Time are not correct.
EFI_SUCCESS	Time is a valid EFI_TIME variable.

Definition at line 1169 of file PcRtc.c.

◆ RtcWaitToUpdate()

EFI_STATUS RtcWaitToUpdate ( UINTN Timeout )

Wait for a period for the RTC to be ready.

Parameters

Timeout Tell how long it should take to wait.

Return values

EFI_DEVICE_ERROR	RTC device error.
EFI_SUCCESS	RTC is updated and ready.

Definition at line 1124 of file PcRtc.c.

◆ RtcWrite()

STATIC VOID RtcWrite	(	IN UINTN	Address,
		IN UINT8	Data
	)

Write RTC through its registers.

Parameters

Address	Address offset of RTC. It is recommended to use macros such as RTC_ADDRESS_SECONDS.
Data	The content you want to write into RTC.

Definition at line 179 of file PcRtc.c.

Variable Documentation

◆ mDayOfMonth

UINTN mDayOfMonth[] = { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }

Definition at line 22 of file PcRtc.c.

◆ mMaximalValidYear

UINT16 mMaximalValidYear

extern

Definition at line 23 of file PcRtcEntry.c.

◆ mMinimalValidYear

UINT16 mMinimalValidYear

extern

Definition at line 22 of file PcRtcEntry.c.

◆ mRtcDefaultYear

UINT16 mRtcDefaultYear

extern

Definition at line 21 of file PcRtcEntry.c.

◆ mRtcIndexRegister

UINTN mRtcIndexRegister

extern

Definition at line 19 of file PcRtcEntry.c.

◆ mRtcTargetRegister

UINTN mRtcTargetRegister

extern

Definition at line 20 of file PcRtcEntry.c.

◆ mTimeZoneVariableName

CHAR16 mTimeZoneVariableName[] = L"RTC"

Definition at line 27 of file PcRtc.c.

Functions

Variables

Detailed Description

Function Documentation

◆ CheckAndConvertBcd8ToDecimal8()

◆ CompareHMS()

◆ ConvertEfiTimeToRtcTime()

◆ ConvertRtcTimeToEfiTime()

◆ DayValid()

◆ GetCenturyRtcAddress()

◆ IoRtcRead()

◆ IoRtcWrite()

◆ IsLeapYear()

◆ IsWithinOneDay()

◆ MmioRtcRead()

◆ MmioRtcWrite()

◆ PcRtcAcpiTableChangeCallback()

◆ PcRtcGetTime()

◆ PcRtcGetWakeupTime()

◆ PcRtcInit()

◆ PcRtcSetTime()

◆ PcRtcSetTimeZone()

◆ PcRtcSetWakeupTime()

◆ RtcRead()

◆ RtcTimeFieldsValid()

◆ RtcWaitToUpdate()

◆ RtcWrite()

Variable Documentation

◆ mDayOfMonth

◆ mMaximalValidYear

◆ mMinimalValidYear

◆ mRtcDefaultYear

◆ mRtcIndexRegister

◆ mRtcTargetRegister

◆ mTimeZoneVariableName