I. Switch to the external BIOS.

Use the external BIOS flash chip to boot COMe.

root@bmc:~# source /usr/local/bin/openbmc-utils.sh
root@bmc:~# gpio_set BRG_COM_BIOS_DIS0_N 1
root@bmc:~# gpio_set BRG_COM_BIOS_DIS1_N 0

Make sure the external BIOS connects to COMe instead of BMC.

root@bmc:~# gpio_set COM6_BUF_EN 0
root@bmc:~# gpio_set COM_SPI_SEL 0

Reset the COMe module.

root@bmc:~# wedge_power.sh reset;sol.sh
Power reset microserver ... Done
You are in SOL session.
Use ctrl-x to quit.
-----------------------

[Note] If there is no image in the external BIOS, please refer to the following link first.

[Wedge100BF] How to flash the external BIOS ?

II. Enter the external BIOS UEFI shell.

Click "ESC" when prompt as below.

At "Save & Exit" page, choose [Built-in EFI shell].

III. Switch to the BMC (use ctrl-x to quit) and set GPIO pin to the main BIOS.

Use the main BIOS flash chip to boot COMe.

root@bmc:~# source /usr/local/bin/openbmc-utils.sh
root@bmc:~# gpio_set BRG_COM_BIOS_DIS0_N 0
root@bmc:~# gpio_set BRG_COM_BIOS_DIS1_N 0

Switch to external BIOS UEFI shell.

root@bmc:~# sol.sh
You are in SOL session.
Use ctrl-x to quit.
-----------------------

IV. Switch to the external BIOS UEFI shell to burn the main BIOS.

Reference: [Wedge] BIOS upgrade procedures

V. Power off the device - cold reboot(unplug and replug the power cord).

Warning!!!

Please DO NOT exit UEFI shell and select "Save Changes and Reset" option from BIOS.