build: allow specifying flow-control to grub on serial console

On the more sophisticated (i.e. deeper FIFO) serial controllers,
flow-control might be needed to avoid dropping output.

Signed-off-by: Philip Prindeville <philipp@redfish-solutions.com>
This commit is contained in:
Philip Prindeville 2017-02-06 20:33:36 -07:00 committed by Felix Fietkau
parent dfacdc6a99
commit 7fe5963be0
2 changed files with 7 additions and 2 deletions

View file

@ -203,6 +203,11 @@ menu "Target Images"
default 38400 if TARGET_x86_generic
default 115200
config GRUB_FLOWCONTROL
bool "Use RTE/CTS on serial console"
depends on GRUB_SERIAL != ""
default n
config GRUB_BOOTOPTS
string "Extra kernel boot options"
depends on GRUB_IMAGES

View file

@ -32,8 +32,8 @@ endif
GRUB_SERIAL:=$(call qstrip,$(CONFIG_GRUB_SERIAL))
ifneq ($(GRUB_SERIAL),)
GRUB_CONSOLE_CMDLINE += console=$(GRUB_SERIAL),$(CONFIG_GRUB_BAUDRATE)n8
GRUB_SERIAL_CONFIG := serial --unit=0 --speed=$(CONFIG_GRUB_BAUDRATE) --word=8 --parity=no --stop=1 --rtscts=off
GRUB_CONSOLE_CMDLINE += console=$(GRUB_SERIAL),$(CONFIG_GRUB_BAUDRATE)n8$(if $(CONFIG_GRUB_FLOWCONTROL),r,)
GRUB_SERIAL_CONFIG := serial --unit=0 --speed=$(CONFIG_GRUB_BAUDRATE) --word=8 --parity=no --stop=1 --rtscts=$(if $(CONFIG_GRUB_FLOWCONTROL),on,off)
GRUB_TERMINALS += serial
endif