Intel Extensible Firmware Interface - Manual (Page 203)

Services — Runtime Services
Version 1.10 12/01/02 6-11
//*******************************************************
// Bit Definitions for EFI_TIME.
Daylight. See below.
//*******************************************************
#define EFI_TIME_ADJUST_DAYLIGHT
0x01
#define EFI_TIME_IN_DAYLIGHT 0x02
//*******************************************************
// Value Definition for EFI_TIME.
TimeZone. See below.
//*******************************************************
#define EFI_UNSPECIFIED_TIMEZONE
0x07FF
Year, Month, Day The current local date.
Hour, Minute, Second, Nanosecond
The current local time. Nanoseconds report the current fraction
of a second in the device. The format of the time is
hh:mm:ss.nnnnnnnnn . A battery backed real time clock
device maintains the date and time.
TimeZone The time’s offset in minutes from GMT. If the value is
EFI_UNSPECIFIED_TIMEZONE , then the time is interpreted
as a local time.
Daylight A bitmask containing the daylight savings time information for
the time.
The EFI_TIME_ADJUST_DAYLIGHT bit indicates if the time
is affected by daylight savings time or not. This value does not
indicate that the time has been adjusted for daylight savings
time. It indicates only that it should be adjusted when the
EFI_TIME enters daylight savings time.
If EFI_TIME_IN_DAYLIGHT is set, the time has been
adjusted for daylight savings time.
All other bits must be zero.