CP6006-SA – User Guide, Rev. 0.5 Preliminary
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8.4.2.
Device Locator Record
The device ID string which can be found by reading the Device Locator Record (SDR Type 12h) contains the string
“BMC:x ... x”. For example, invoking the “ipmitool” command
ipmitool sdr list mcloc
will return the device ID
strings of all available boards. If the IPMI controller is in BMC mode, this string will be displayed without change. If the
IPMI controller is in SMC mode, then the string will be changed into “Sxx: x ... x” where xx is the slot number where the
board is residing, e.g. “S09: x ... x”.
8.5.
Board Control Extensions
8.5.1.
SPI Boot Flash Selection—uEFI BIOS Failover Control
The uEFI BIOS code is stored in two different SPI boot flash devices designated as the standard SPI boot flash and the
recovery SPI boot flash.
By default, the uEFI BIOS code stored in the standard SPI boot flash is executed first. If this fails, the uEFI BIOS code in
the recovery SPI boot flash is then executed.
During boot-up, the uEFI BIOS reports its operational status to the IPMI controller within a given time. If the status is
"failed" or not reported within the given time, the IPMI controller selects the recovery SPI boot flash, resets the
board's processor, and waits for the status report from the uEFI BIOS again.
In the event the recovery boot operation fails, the IPMI controller reports it, but takes no further action of its own.
When a boot operation fails, a "Boot Error - Invalid boot sector" event is asserted for the related sensor:
"FWH0 Boot Err" sensor indicates the standard SPI boot flash has failed
"FWH1 Boot Err" sensor indicates the recovery SPI boot flash has failed
8.5.2.
uEFI BIOS Boot Order Selection
Normally the uEFI BIOS will apply the boot order which was selected in the uEFI BIOS menu “uEFI Boot/Boot Option
Priorities”. But there is another alternative boot order which is stored in the IPMI controller's non-volatile memory.
This boot order can be set and read by IPMI OEM commands. At payload start the IPMI controller writes this boot
order into a register where the uEFI BIOS can read it. If this IPMI controller's boot order has a non-zero value, the uEFI
BIOS will use it instead of its own boot order.