[U-Boot-Users] BDI2000 vs Vision-ICE

[Mike Wellington <wellington@lucent.com>]

Guys-
   My replies are in post.

-thanks

mike wellington
wellington at lucent.com


VanBaren, Gerald (AGRE) wrote:

> I've used both VisionICE and BDI2000 (we bought two 
VisionICEs initially and only BDI2000s since then :-).
Both connect via the JTAG port and neither support traceback.
As Charlie points out, traceback requires capturing the
address and data bus which is bloody tricky on todays processors.
> 
my project lead thinks visionIce/visionEvent has solved that
problem.   Since our CPU core is inside an FPGA I guess I could
conceivably watch the bus with ChipScope - an FPGA-based
logic analyzer which would give me raw bus cycles.

> With a JTAG or a software only debugger you could theoretically 
enable the "trace on branch" PPC exception and run at full
speed in (very short :-) bursts, saving each branch location
and then rebuild the traceback using the saved the branches,
but that would still cause a significant speed degradation
because of all the exceptions.  I don't know if anyone does this.

I don't know if anyone does this either, but I think it is
an excellent idea.

I have my doubts whether this would be useful due to the speed slowdown.
> 

I think my application can handle the speed slowdown.

>>-----Original Message-----
>>From: u-boot-users-admin at lists.sourceforge.net
>>[mailto:u-boot-users-admin at lists.sourceforge.net]On Behalf Of Wells,
>>Charles
>>Sent: Thursday, January 08, 2004 5:57 PM
>>To: u-boot-users at lists.sourceforge.net
>>Cc: 'Mike Wellington'
>>Subject: RE: [U-Boot-Users] BDI2000 vs Vision-ICE
>>
>>
>>Mike,
>>
>>
>>>People at my place of work are telling me that the
>>>Vision-Ice supports "backtrace" and the BDI2000 does
>>>not.
>>
>>I don't believe visionICE supports what you describe, but visionEVENT
>>(another WRS/EST product) does.  visionEVENT behaves like a 
>>classic "bus
>>capture" analyzer.  It's no longer a "10-bin BDM port 
>>connected device."
>>visionEVENT is housed in a seperate box that attaches to the 
>>bottom of the
>>visionICE case and requires two 80-pin high-density connectors on your
>>target for its connection.  Further, visionEVENT imposes some nasty
>>restrictions on the target (e.g. not being able to run the 
>>CPU clock at 2x
>>bus clock).
>>
>>We bought the visionICE/visionEVENT stuff a couple of years 
>>ago.  I use
>>visionICE regularly and it works adequately for bringing up 
>>new targets and
>>debugging startup code.  We haven't use visionEVENT much at 
>>all.  We've just
>>never needed its capabilities.  I've never used the BDI2000, 
>>but it sounds
>>like its Linux integration is better than either visionICE or 
>>visionEVENT
>>(although WRS may have improved this since we took delivery 
>>of ours).

Some think the visionICE, visionEVENT stuff has improved.  I'll
find out soon enough since management went ahead and bought it.

>>
>>BTW, I agree with Wolfgang's earlier point.  What really 
>>matters is the
>>capabilities of the debugger software front-end.  One of 
>>these days, I need
>>to get someone around here to approve the purchase of a 
>>BDI2000 and see how
>>it compares.
>>

Our debugger front-end is supposed to be great.  I haven't
fired it up yet for real.  I kinda need a U-Boot bootloader
for the Xilinx ML300/PPC405 first.   Or I could use Redboot ( part
of eCos Real-Time OS ) which I already have sorce for a ML300/PPC405
but I haven't figured out how to build it yet.


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