Bitstream manipulation

[Gabriel Cobos Tello]

Greetings!

Im using rapidwright to manipulate bitstreams for the purpose of fault injection.

To this extend I have done the following:

configArray.updateUserStateBits(mycells3.get(0));

Where mycell3.get(0) is the cell whose properties i have altered.

What I want is to be able to generate a Fault List based on the changes done in the netlist with rapidwright. What I am missing is the ability to find the address and content of the specific frames which have changed. Basically im trying to get a list of FARs and their respective changed bits.

I have tried the following to obtain the frames that could reflect the changes:

Block TargetBlock = configArray.getConfigBlock(mycells3.get(0).getTile());

TargetFrames = TargetBlock.getFrames();

This has given the list of frames in which the changes will be reflected. With this I could iterate and compare with the unchanged bitstream to find out the altered frames. And from this I could obtain the desired faultlist and hence the differential bitstream.

My question is if there is a way to do this with rapidwright methods without having to do all the frame fishing manually. I know i can modify the entire bitstream with rapidwright to reflect the changes, but this isnt what i want. Can rapidwright generate a differential bitstream?

Any help is appreciated.

Best regards,

Gabriel.

[RapidWright]

Hi Gabriel,

Apologies for the delayed response, Google Groups email notifications have been unreliable as of late.

I think I see what you are asking for and you are correct.  There aren't any APIs that explicitly do what you request.  Perhaps you could file a new issue and we could consider adding some of that functionality.

Thanks,

Chris

[Gabriel Cobos Tello]

Hi Cris,

I will do as you say then! I think rapidwright has a lot of potential to facilitate fault injection on FPGAs, which can be a great hassel without knowledge of the bitstream configuration.

On that note I have another question if thats alright,  can rapidwirht work with vivado essential bit files? I want to be able to inject faults by flipping essential bits, and was wondering if that would be supported in rapidwright. 

Cheers,

Gabriel.

[RapidWright]

Hi Gabriel,

I'm not familiar with Vivado essential bit files, so RapidWright probably doesn't support that out of the box.  

Chris