Flashing BIOS in Linux can be achieved via flashrom

flashrom can be installed on your favorite linux distro or used via a live distribution as Parted Magic or SystemRescueCD

Instructions

• identify chipset
  
  flashrom -p internal

  1	flashrom -p internal

• backup current bios
  
  flashrom -p internal -r bios_old.rom

  1	flashrom -p internal -r bios_old.rom

• write new bios
  
  flashrom -p internal -w bios_image.rom

  1	flashrom -p internal -w bios_image.rom