+GRUB_TERMINALS =
+GRUB_SERIAL_CONFIG =
+GRUB_TERMINAL_CONFIG =
+GRUB_CONSOLE_CMDLINE =
+
+ifeq ($(CONFIG_X86_GRUB_CONSOLE),y)
+GRUB_CONSOLE_CMDLINE += console=tty0
+GRUB_TERMINALS += console
+endif
+
+ifneq ($(CONFIG_X86_GRUB_SERIAL),)
+GRUB_CONSOLE_CMDLINE += console=$(strip $(subst ",, $(CONFIG_X86_GRUB_SERIAL))),$(CONFIG_X86_GRUB_BAUDRATE)n8
+GRUB_SERIAL_CONFIG = serial --unit=0 --speed=$(CONFIG_X86_GRUB_BAUDRATE) --word=8 --parity=no --stop=1
+GRUB_TERMINALS += serial
+endif
+
+ifneq ($(GRUB_TERMINALS),)
+GRUB_TERMINAL_CONFIG = terminal --timeout=2 $(GRUB_TERMINALS)
+endif