new CW Ethernet/USB TAP vs BDI3000

[antoniogoncalve]

Hi there,

I'm considering to buy a new probe for personal usage. This is quite a bit investment for me so I have problems to take a decision.

I want to target PowerQuicc and Qorlq.

I'm considering the new CW TAP and BDI3000 because both have GDB board bring up support and therefore I would avoid investing in SW at the moment.

However the Bdi3000 is lot more expensive than the CW.

Do you know if it worths the diference? Did anyone work with both USB TAP and BDIx000 for comparing?

Many thanks in advance for your review,

Best regards,

         Antonio

[sinanakman]

Hi Antonio, if you are planning to do kernel debugging, BDI3000 has the feature to use kernel page tables for address translation. Last time I checked my understanding was that CW TAP did not have this ability. I might have misunderstood then but if kernel debugging is one of your main activities, you might want to double check for this ability.

Hope this helps.

[antoniogoncalve]

Hi Sinan,

   thanks for your answer. That's a good point. Actually MMU and cache management are some of the main requirement fields for me. It is not clear which debugging capabilities has the cwtap for instance on these fields. I did post that question to Marius.

Best regards,

     Antonio

[sinanakman]

Hi Antonio

To make this a bit more clear, CWTAP probably does support debugging while MMU and caches are enabled. What I was referring to was specific to Linux kernel debugging where BDI3000 has this feature that would take Linux kernel page tables into consideration for address translation. When you are using gdb over CWTAP, I assume the addresses you enter will be translated if at that point MMU is enabled or will be treated as physical address before MMU is enabled. I am not familiar with CWTAP so someone from FSL should confirm all these. I am more familiar with BDI3000 for all the platforms you mentioned earlier so if you have specific questions for that please let me know. This would, however, be probably under another topic to discuss.

Hope this helps.

  Sinan Akman

[marius_grigoras]

Hi Antonio,

I need more information about this topic. You're going to debug linux and how many PowerQuicc targets are we talking about? Also what are these boards - if you can please provide the board names.

If we already support your boards and the debugging procedure flow then the best way is cwtap.

Thank you in advance for your answer,

Marius

[antoniogoncalve]

Hi Marius,

thanks a lot for you answer,

I would like to use the TWR-P1025 first, in some months the P2040 and ideally having as a reference the MPC8313RDB e.g. comparing memory access time, single-core vs dual and quad.

I want mostly to debug without any OS. I'm more interested in implementing my own bootstrap.

Thanks a lot in advance for your reviews

best regards,

       Antonio

[marius_grigoras]

Hi Antonio,

I received the response from technical team:

"Right now p2040 is supported by gdb-jtag.

Twr-p1025 – may need changes in gdb init script, only p1020 has been tested and init script is provided.

MPC8313RDB – not supported and we do not have resources to implement the support in the near future."

So, you can use CWTAP for P2040 and twr-p1025. Please let me know if you need to start with twr-p1025, I'll keep'n touch with technical team to see if they can provide ASAP the updated script.

Regards,

Marius

[antoniogoncalve]

Hi Marius,

my main development requirements are related with memory protection and memory access determinism. Is the cwtap gdb able to debug using MMU, for instance memory translation as pointed by Sinan, caches,etc?

Where can I find a document regarding the current gdb/gdbproxy debug for the cwtap capabilities?

thanks again for your kind answer,

     Antonio