From 876b03102d6ebc39728e44a9418e525f4973c68b Mon Sep 17 00:00:00 2001
From: Ying Xie <ying.xie@microsoft.com>
Date: Wed, 31 Oct 2018 23:48:15 +0000
Subject: [PATCH] [console speed] lock console speed to start up speed

Auto negotiating console speed could cause sonic to lock on a wrong
speed under rare conditions. The only way to come out of the wrong
speed is to issue line break or restart console service with forced
speed, or reboot sonic.

Lock down the console speed to avoid these situations.

Signed-off-by: Ying Xie <ying.xie@microsoft.com>
---
 files/image_config/platform/rc.local | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/files/image_config/platform/rc.local b/files/image_config/platform/rc.local
index 0db4278932f6..acac42e326e1 100755
--- a/files/image_config/platform/rc.local
+++ b/files/image_config/platform/rc.local
@@ -128,6 +128,19 @@ process_reboot_cause() {
     echo "Unexpected reboot" > $REBOOT_CAUSE_FILE
 }
 
+program_console_speed()
+{
+    speed=$(cat /proc/cmdline | grep -Eo 'console=ttyS[0-9]+,[0-9]+' | cut -d "," -f2)
+    if [ -z "$speed" ]; then
+        CONSOLE_SPEED=9600
+    else
+        CONSOLE_SPEED=$speed
+    fi
+
+    sed -i "s|\-\-keep\-baud .* %I| $CONSOLE_SPEED %I|g" /lib/systemd/system/serial-getty@.service
+    systemctl daemon-reload
+}
+
 #### Begin Main Body ####
 
 # Set up previous and next reboot cause files
@@ -209,6 +222,8 @@ fi
 
 . /host/machine.conf
 
+program_console_speed
+
 if [ -f $FIRST_BOOT_FILE ]; then
 
     echo "First boot detected. Performing first boot tasks..."