Server Management Functional Specifications; Bmc Internal Timestamp Clock; Figure 24. Integrated Bmc Hardware - Intel S2600IP Technical Product Specification

Intel® Server Board S2600IP and Intel® Workstation Board W2600CR TPSPlatform Management Overview
4.2

Server Management Functional Specifications

4.2.1

BMC Internal Timestamp Clock

The BMC maintains an internal timestamp clock that is used by various BMC subsystems, for
example, time stamping SEL entries. As part of BMC initialization after AC power is applied or
the BMC is reset, the BMC initializes this internal clock to the value retrieved from the SSB
component's RTC from a SMBus* slave read operation. This is the system RTC and is on the
battery power well so it maintains the current time even when there is no AC supplied to the
system.
4.2.1.1 System Clock Synchronization
The BIOS must send the Set SEL Time command with the current system time to the BMC
during system Power-on Self Test (POST). Synchronization during very early POST is
preferred, so that any SEL entries recorded during system boot can be accurately time
stamped. Additionally, during sleep state transitions other than S0 the BIOS will synchronize the
time.
If the time is modified through an OS interface, then the BMC's time is not synchronized until the
next system reboot.
Revision 1.1

Figure 24. Integrated BMC Hardware

Intel order number G34153-003
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