Kontron CP6003-RC IPMI - Manual (Page 37)

CP6003-SA/RA/RC IPMI Firmware
ID 1045-5656, Rev. 2.0 Page 37
P R E L I M I N A R Y
11. uEFI BIOS Failover Control - Automatic SPI
Boot Flash Selection
When the CP6003-SA/RA/RC's payload starts, the first code to be executed is the uEFI BIOS.
There are two SPI boot flash devices (standard and recovery), which may contain different uEFI
BIOS codes. Which one of them will be utilized from the next boot process on is defined by one
of two ways:
• The IPMI controller determines whether to boot from the standard or the recovery SPI
boot flash. The IPMI firmware’s parameter used for this function is configured via the
OEM IPMI command Set Control State. The IPMI controller stores this parameter
in the EEPROM (refer to Chapter 6.3, Set Control State).
• Setting the DIP Switch SW1, switch 2, to ON results in booting from the recovery SPI boot
flash regardless of the IPMI firmware setting.
11.1 Automatic SPI Boot Flash Selection During the Boot Pro-
cess
After each payload reset the IPMI controller selects the SPI boot flash by applying the related
EEPROM parameter.
Physically the IPMI controller sets or resets a signal line. Afterwards, it waits for a special
message from the uEFI BIOS. This message contains the checksum report, i.e. it indicates the
validity of the SPI boot flash's checksum.
If the Set Control State OEM command byte 2 is set to 00h and the DIP switch SW1, switch 2,
is OFF, the uEFI BIOS boots from the standard SPI boot flash. If the checksum is wrong or the
message is not received within 60 seconds, then the standard SPI boot flash is assumed to
contain an invalid or a corrupted image. In this case, the IPMI controller selects the recovery
SPI boot flash and reset the board again.
If the Set Control State OEM command byte 2 is set to 01h or the DIP switch SW1, switch 2, is
ON, the uEFI BIOS boots from the recovery SPI boot flash. With this setting, the IPMI controller
does not switch over to the standard SPI boot flash if the checksum is wrong or the message
is not received. In this case, the board freezes. For this reason, it is recommended to use the
standard SPI boot flash as a default boot flash.
In case of a boot failure, the IPMI controller issues a “Boot Error (Invalid boot sector) event” by
setting the appropriate sensor value (sensor “FWHx Boot Err”. x = 0..1). “x” is the number of
the used SPI boot flash (0 = standard SPI boot flash; 1 = recovery SPI boot flash). Afterwards,
it causes a payload-off/on cycle and continues as described at the beginning of this chapter.
11.2 OS Boot Order Selection by OEM IPMI
Normally the uEFI BIOS will apply the OS 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.