build: allow specifying flow-control to grub on serial console
authorPhilip Prindeville <philipp@redfish-solutions.com>
Tue, 7 Feb 2017 03:33:36 +0000 (20:33 -0700)
committerFelix Fietkau <nbd@nbd.name>
Mon, 3 Apr 2017 06:51:02 +0000 (08:51 +0200)
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>
config/Config-images.in
target/linux/x86/image/Makefile

index f59a336..95752f7 100644 (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
index f34788d..ca5d012 100644 (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