Add Formal Verification and Fix Bug#5
Open
AngeloJacobo wants to merge 5 commits intoRoaLogic:masterfrom
Open
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Good day,
I added formal verification using the open source symbiyosys. There was a bug found: when the overall parity bit itself is corrupted, the sb_err flag is not triggered. The updated code fixed this error on
ecc_dec.sv.The formal verification can be run by just running
./run_formal.shinside the./formaldirectory. Just make sure the symbiyosys tool is installed on your system (recommended way is to install the OSS-CAD-SUITE : https://github.com/YosysHQ/oss-cad-suite-build/releases). Shown below is the summary report at the end:The formal verification runs a set of tasks (shown on
ecc.sby), where K is 8, 16,32, and 64. Proof for K=64 takes the longest time reaching almost one and a half hour.The actual formal properties are very simple and is elaborated on
ecc_formal.v. Basically, the main rule is that the information input received by ecc_enc must be the same as the information output from ecc_dec (in case of 0 or 1 flipped bits). If 2 flipped bits, then the db_err must be high.I also added cover statement so we can have a sample waveform of this working design.
Thank you!
Kind regards,
Angelo
ps: Awesome project by the way! The design is very simple but flexible! I'm planning to use this ECC for my open source DDR3 controller UberDDR3: https://github.com/AngeloJacobo/UberDDR3
ps: Included on these commits are the same ones from my PR:
Fix failing VIvado Simulationsince that PR is not yet accepted