Specifications

QSSC-S4R Technical Product Specification Processor Presence and Population Check
283
Table 188 shows outputs that can be tested via the Set SM Signal command.
Table 189. Set SM Signal Command Signal Definition
Signal Name Signal ID Instances Notes
Fan power/speed 05h Note 1 For “force assert” actions, request byte 4 is
required.
For all other actions, request byte 4 is
reserved, and should not be sent with the
request.
System Fault LED (amber) 01h Note 1 Request byte 4 is optional, and has no
effect on the command.
System Ready LED (green) 0Fh Note 1 Request byte 4 is optional, and has no
effect on the command.
Table 190 shows the inputs (buttons / switches) that can be tested via the Get SM Signal command.
Table 191. Get SM Signal Command Signal Definition
Signal Name Signal ID Instances
Power button 00h N/A
Reset button 01h N/A
Fan Power/Speed 0Dh N/A
24.31 Component Fault LED Control
Several sets of component fault LEDs are supported. Some LEDs are owned by the BMC and some by the BIOS.
The BMC owns control of the following FRU / fault LEDs:
x Fan fault LEDs – A fan fault LED is associated with each fan. The BMC lights a fan fault LED if the associated fan
tach sensor has a lower critical threshold event status asserted. Fan tach sensors are manual rearm sensors.
Once the lower critical threshold is crossed, the LED remains lit until the sensor is rearmed. These sensors are
rearmed at system DC power-on and system reset. Whenever any of fan fault LED lits, the Global Fan Fault LED
also lit.
x DIMM fault LEDs - The BMC owns the HW control for these LEDs. The LEDs reflect the state of BIOS-owned
event-only sensors. When BIOS detects a DIMM fault condition, it sends an IPMI OEM command (Set Fault
Indication) to the BMC to instruct the BMC to turn on the associated DIMM Fault LED. These LEDs are only active
when the system is in the ‘on’ state. The BMC will not activate or change the state of the LEDs unless instructed by
the BIOS.BIOS must send updated fault( or clear fault) every time after POST, DIMM LED state doesn’t change
during AC reset
24.31.1 Set Fault Indication Command
The Set Fault Indication command can be used by satellite controllers and system management software to
communicate fan, temperature, power, and drive fault states to the BMC. The BMC consolidates the state with its own
system state when determining the overall system health. It uses this consolidated state to set the front panel indicator
LED states and to control other behavior, such as fan boosting.
The Set Fault Indication command has a source field that allows the BMC to track the fault states of multiple sources.
Each source must use a separate unique source ID. For example, hot-swap controller 0 is represented by ID 1. Hot-
swap controller 1 is represented by ID 2.
The fault state of each source is tracked independently. Whenever a source sets the fault state for a particular fault
type, such as fan or power, the new state overrides the previous state. The tracked fault state is cleared when the
server is powered up or reset.
24.31.2 DIMM Mapping for Fault Indication and Fan Control Config:
BIOS must follow below population rules for sending DIMM Map for Fault Indication and Fan control configuration
command.