LSI adapters could be easily upgraded without preparing a FreeDOS boot media or playing with UEFI.

Download and Install Tools

ROMs and tools could be dowloaded from Broadcom website. We need to download the install for ESX ( Installer_P20_for_Vmware_ESX50 ) and the MS-DOS package ( 9210-8i_Package_P20_IR_IT_FW_BIOS_for_MSDOS_Windows, since this includes both the firmware and BIOS).

Unzip the packges for vmware-esx-sas2flash.vib, mptsas2.rom and 2108it.bin, then use scp or DCUI to transfer them to ESXi. Then install sas2flash vib package on ESXi host.

esxcli software vib install --force -v /tmp/vmware-esx-sas2flash.vib

Flash LSI Adapter

First check the current firmware version.

[root@vmx-1:~] /opt/lsi/bin/sas2flash -list
LSI Corporation SAS2 Flash Utility
Version 20.00.00.00 (2014.09.18) 
Copyright (c) 2008-2014 LSI Corporation. All rights reserved 

	Adapter Selected is a LSI SAS: SAS2008(B1)   

	Controller Number              : 0
	Controller                     : SAS2008(B1)   
	PCI Address                    : 00:01:00:00
	SAS Address                    : 5003005-7-00b8-5eb0
	NVDATA Version (Default)       : 14.01.00.08
	NVDATA Version (Persistent)    : 14.01.00.08
	Firmware Product ID            : 0x2213 (IT)
	Firmware Version               : 20.00.06.00
	NVDATA Vendor                  : LSI
	NVDATA Product ID              : SAS9211-8i
	BIOS Version                   : 07.39.02.00
	UEFI BSD Version               : N/A
	FCODE Version                  : N/A
	Board Name                     : SAS9211-8i
	Board Assembly                 : N/A
	Board Tracer Number            : N/A

	Finished Processing Commands Successfully.
	Exiting SAS2Flash.

If sas2flash insists that no LSI cards could be detected, check if the card is toggled PCI passthrough. Once the system is ready to flash the firmware, it is simple to do it with one command.

[root@vmx-1:~] /opt/lsi/bin/sas2flash -o -f /tmp/2108it.bin -b /tmp/mptsas2.rom 
LSI Corporation SAS2 Flash Utility
Version 20.00.00.00 (2014.09.18) 
Copyright (c) 2008-2014 LSI Corporation. All rights reserved 

	Advanced Mode Set

	Adapter Selected is a LSI SAS: SAS2008(B1)   

	Executing Operation: Flash Firmware Image

		Firmware Image has a Valid Checksum. 
		Firmware Version 20.00.07.00
		Firmware Image compatible with Controller. 

		Valid NVDATA Image found. 
		NVDATA Version 14.01.00.00 
		Checking for a compatible NVData image... 

		NVDATA Device ID and Chip Revision match verified.
		NVDATA Versions Compatible.
		Valid Initialization Image verified.
		Valid BootLoader Image verified.

		Beginning Firmware Download...
		Firmware Download Successful.

		Verifying Download...

		Firmware Flash Successful.

		Resetting Adapter...
		Adapter Successfully Reset.

	Executing Operation: Flash BIOS Image

		Validating BIOS Image...

		BIOS Header Signature is Valid

		BIOS Image has a Valid Checksum. 

		BIOS PCI Structure Signature Valid.

		BIOS Image Compatible with the SAS Controller.

		Attempting to Flash BIOS Image...

		Verifying Download...

		Flash BIOS Image Successful.

		Updated BIOS Version in BIOS Page 3.

	Finished Processing Commands Successfully.
	Exiting SAS2Flash.

Then check the firmware (and BIOS) version again.

[root@vmx-1:~] /opt/lsi/bin/sas2flash -list
LSI Corporation SAS2 Flash Utility
Version 20.00.00.00 (2014.09.18) 
Copyright (c) 2008-2014 LSI Corporation. All rights reserved 

	Adapter Selected is a LSI SAS: SAS2008(B1)   

	Controller Number              : 0
	Controller                     : SAS2008(B1)   
	PCI Address                    : 00:01:00:00
	SAS Address                    : 5003005-7-00b8-5eb0
	NVDATA Version (Default)       : 14.01.00.06
	NVDATA Version (Persistent)    : 14.01.00.08
	Firmware Product ID            : 0x2213 (IT)
	Firmware Version               : 20.00.07.00
	NVDATA Vendor                  : LSI
	NVDATA Product ID              : SAS9210-8i
	BIOS Version                   : 07.39.02.00
	UEFI BSD Version               : N/A
	FCODE Version                  : N/A
	Board Name                     : SAS9211-8i
	Board Assembly                 : N/A
	Board Tracer Number            : N/A

	Finished Processing Commands Successfully.
	Exiting SAS2Flash.