Please try following steps. We will also add these to the readme.txt soon.

Regards

-harsh

How to Debug

This section describes how to enable debug messages from various components on serial port during system bootup.

Serial Port connection

Finding serial port address:

1. $ dmesg | grep tty
2. Check for address associated with the serial port ttyS0. For most machines, it is <ttyS0 addr> = 0x3f8.

Note: If serial port address is different on your machine, use that instead of 0x3f8 while following instructions on this section.

Set up connection through serial port:

1. Connect your development machine, com1 to another machine, com2 where you will collect debug messages.
2. Install minicom and set up serial port on both machines. Use 115200 as the baud rate. For more info on this see https://help.ubuntu.com/community/Minicom.
3. Test whether serial port is properly setup by typing in minicom on com1 and see if it's being displayed in real time on com2 and vice versa.

Kernel Messages

Enable debug output from kernel to go on serial port:

1. Update grub default configure file to print linux kernel log to screen                       $ sudo vi /etc/default/grub
2. Make following changes:                         GRUB_CMDLINE_LINUX_DEFAULT="console=tty0 console=ttyS0,115200n8". The ttyS0 should be changed to your real serial port name.
3. Note: The above cmdline for linux kernel is enough. If you want more log before serial port init, you can change the cmdline like below:          GRUB_CMDLINE_LINUX_DEFAULT="debug ignore_loglevel log_buf_len=10M print_fatal_signals=1 LOGLEVEL=8 earlyprintk=vga,keep sched_debug console=tty0 console=ttyS0,115200n8"
   Detail info: https://wiki.archlinux.org/index.php/Boot_debugging
   $ sudo update-grub
4. Double check linux kernel can print to screen and serial port both.

Ikgt & Tboot Messages

Enable debug output from tboot, ikgt loader, and ikgt to go on serial port:

1. Edit grub.d/20_linux_ikgt_tboot file. Edit value of ikt_log and tboot_log in all instances:

       if [ -d /sys/firmware/efi ] ; then

           ikgt_log="iobase=0x3f8"

           # there's no vga console available under EFI

           tboot_log="logging=serial,memory serial=115200,8n1,0x3f8 "

       else

           ikgt_log="iobase=0x3f8"

           tboot_log="logging=serial,vga,memory serial=115200,8n1,0x3f8 "

       fi

   2) Update grub.

       $ sudo update-grub

If you wish to change things only temporarily

1. Press ‘e’ to edit the selected boot entry. Modify ikgt entry as needed, press F10

From: Intel-KGT [mailto:intel-kgt-bounces@lists.01.org] On Behalf Of Nibinbin
Sent: Thursday, September 10, 2015 8:31 PM
To: intel-kgt@lists.01.org
Subject: [iKGT] 【ikgt】debug mode

Hi，

I’d like to use IKGT with debug mode,but no serial output based on the version 1.1.

I have done :

1、 build ikgt with “make debug=1”

2、 install ikgt with “make install debug=1”

it seems that something else should be configed.

Best wishes，

Robin Ni