This is just my $0.02 worth but I have used our BDI2000 to debug User land application, Kernel, and device drivers at the same time. It is an invaluable tool when tracking down both software and hardware bugs. In fact I will start hardware debugging with our BDI before cabling up a Logic analyzer. I can say that without a doubt if we had not use the BDI2000 in this way we would have ended up redesigning the hardware to get around some perceived limitations. Instead I found the software bug and fixed it. I did all this in about 3-hours work as well.
I don't use the BDI all the time to debug user mode applications but when you want to stop the hole processor it is invaluable. To be able to step through user code and then jump into the kernel on system calls is just great.
I cannot tell you how much time our BDI has saved us. We also have a Vision ICE in another office I am not completely familiar with the Vision Ice but compared to the functionality I get from a BDI the Vision Ice is a very poor second.
Regards, Rod
-----Original Message----- From: Wolfgang Denk [mailto:wd@denx.de] Sent: Thursday, January 08, 2004 4:46 AM To: David Aldrich Cc: Matias Sundman (AL/EAB); u-boot-users@lists.sourceforge.net Subject: Re: [U-Boot-Users] U-Boot on MPC8280
Dear David,
in message 0E8A20F2EB7BD7119C1F00508BB333780E5D7B@tmservermail02.t-modus.nec.co.uk you wrote:
Is it true that the BDI is not suitable for user app debug? Is this a
Yes, this is true. Well, you _can_ use it, but you have manually navigate through the kernel virtual address space to find what you are looking for. Sometimes this is necessary (typically to find kernel bugs), but this is definitely nothing to do for the average user.
problem in practice?
No, it is not.
Kernel debugging and application debugging are two separate weorlds, like kernel address space and user address space are clearly separated. There is tools for both of them: for the firmware, device drivers and kernel debugging you use the BDI2000, and for user applications you use gdbserver or gdb.
Note that this does not mean any loss of productivity: both the BDI2000 and gdbserver "speak" GDB remote protocol, so you will see absolutely the same user interface.
Best regards,
Wolfgang Denk