Debugging Linux applications on Microblaze

Question

Hello,
could someone please answer some questions who is debugging Linux applications on Microblaze.
I have to prepare an environment to debug applications running on Microblaze Linux 2.6.38. Everywhere, I can find hints how to do it with ARM on Zynq, but this is only a Spartan-6. I might change the Linuxversion but not the hardware.
First, I compiled the kernel 2.6.38 (PLB, big endian) with initramfs_minimal.cpio.gz, then I compiled it with initramfs_complete.cpio.gz. In both cases, the Linux Kernel is running on Microblaze and I can access the filesystem with a serial link and with LAN using telnet.
To debug applications, I tried to run with Windows 7 (64-bit) the Xilinx SDK (Eclipse) included in ISE/XPS 14.7. For Linux applications running on Microblaze, I tried to use the GDB-Debugger in SDK. I think I have to start a GDBserver first and then start SDK to connect to it.
I could not find the GDBserver in the above mentioned filesystems. So, I downloaded the GDB sources for GDB 7.7 and did two configurations. One for the host (first VirtualBox with Ubuntu-Linux-32bit, later Windows 7) and one for the target (microblaze running on spartan-6).
to create the GDBclient for the PC:
configure --prefix=/opt/gdb/mb-linux/cross --target=microblaze-unknown-linux-gnu
The following commands 'make' and 'make install' are running without errors.
to create GDBserver for the FPGA:
configure --prefix=/opt/gdb/mb-linux/native --host=microblaze-unknown-linux-gnu
There is an error with the following command 'make'.
error: Gdb does not support native target microblaze-unknown-linux-gnu
I have really tried a lot, looked at many pages, e.g.:
http://www.wiki.xilinx.com/
Xilinx Wiki - Getting started
Xilinx Wiki - MicroBlaze
Xilinx Wiki - Create Linux Application
Xilinx Wiki -Debug Application
Many links were broken and if accessible, debugging Linux on Zynq or debugging a standalone application on microblaze was described.
It would be very helpful if someone who actually did debug Linux applications on microblaze with or without SDK could describe a little bit how it works.
Is GDB included in either of these filesystems and I did not see it ?
Do I need to create GDBserver ?
What is wrong with my settings to create GDBserver ?
Is there a totally different way to debug ?
Thanks in advance for your help,
Michael

Answer 1

Hello Achutha,
thank you for your reply.
I already knew those two links but I took a close look at them again.
The second link helps to run a Linux kernel on Microblaze. It ends when it's getting interresting for me. It does not describe anything about developing a Linux application.
The first link is using Zynq. Most of the steps can be done with Microblaze as well. When I start debugging, it changes to the debug perspektive and after some seconds I see the message
Hello_Linux_Debug(SDK Linux TCF Agent: Disconnected): Connection refused: connect
SDK.log in the SDK workspace shows:
15:20:34.399 ERROR - Unexpected error while parsing XMD response ?: com.google.gson.JsonSyntaxException: com.google.gson.stream.MalformedJsonException: invalid number or unquoted string near
I tried the following options but nothing helped:
Kernel with initramfs_minimal.cpio.gz and with initramfs_complete.cpio.gz.
Changed the access rights of /tmp (I used it for 'Remote File Path')
In the video for Zynq, it is said:
by default, there is a TCF agent running
I guess, the TCF agent can be seen on Zynq if you list all processes running.
What is the name of the TCF agent?
I guess this one is missing on my Microblaze.
Any other suggestions?
Kind regards,
Michael