Brian Bailey Email: [email protected] Tel: 503 632 7448 Cell: 503 753 6040 Web: brianbailey.us Copyright © 2008 Brian Bailey Consulting Verification is all about answering the question: Have we implemented something correctly ? Copyright © 2008 Brian Bailey Consulting !" # $ %& ' ( ' ) Copyright © 2008 Brian Bailey Consulting Propagation success Bug Checker Stimulus 1. Activate 2. Propagate 3. Detect Design Propagation failure ' *# # $ % $ $ & + Copyright © 2008 Brian Bailey Consulting $ ) % ( ) & , & . . / 0 ( ( 1 ) 2 3 ( & Copyright © 2008 Brian Bailey Consulting ( 4 5 6 7 ( 1 ( Copyright © 2008 Brian Bailey Consulting ( ) ( ) 9 9 9 ( ) ( Copyright © 2008 Brian Bailey Consulting 8 $ Propagation success Bug Checker Stimulus 1. Activate Design Propagation failure $ # ! " " "! ! ! " ! % & ! # # ! ! ! # Copyright © 2008 Brian Bailey Consulting 7 ( # 4 : . # '+1 7 Copyright © 2008 Brian Bailey Consulting ) ' ! Propagation success Bug Checker Stimulus 1. Activate 2. Propagate Design Propagation failure $! " ## " ! ! " ! ! !# ! Copyright © 2008 Brian Bailey Consulting ! ( . ) " ; : ) ) 9 < > > ) ) ( ) ( ) ? 5 = ) ) Copyright © 2008 Brian Bailey Consulting # 9 9 9 # ) Copyright © 2008 Brian Bailey Consulting # : & : @ > ) # 9 ) ) 9 %& Copyright © 2008 Brian Bailey Consulting 9 7 ) 9 / 5 2 3 ( : (% 9 ) , % Copyright © 2008 Brian Bailey Consulting 0 1 ) * -) 9 : 8 -:4 . . . -) ) : ? Copyright © 2008 Brian Bailey Consulting $ ! # + 5 9 4) 4) # 4) A 4) : 7 4) 4) # - A - 1 ( 4) 4) # 1 - 9 )* 1 - 1 A 1 ;B > 1 ;B > " Copyright © 2008 Brian Bailey Consulting - 1 : ' 7 9 + % +1 + = + 1 0 ! ) : C 7 # & Copyright © 2008 Brian Bailey Consulting > * ) ) ) ( % )) ) ) Copyright © 2008 Brian Bailey Consulting ) ' ( 4 % %= *) ; 1 ) ) 7 DEFD DEGH Copyright © 2008 Brian Bailey Consulting * Principles Induce mutations (or faults) in the HDL code and show that the verification suite detects those mutations by executing testcases Original program code: a = b or c; Faulty program code: a = b and c; Copyright © 2008 Brian Bailey Consulting + ' 5 ' ' & ' & I) B&= 5 ) J) JK&KK LK ) / 0 Copyright © 2008 Brian Bailey Consulting ) ) < 7 9 == # 5 $ % $ C # $ & $ ) ( # ) 1 % ) ) Copyright © 2008 Brian Bailey Consulting $ ( - @ ; & ; # ; + M Copyright © 2008 Brian Bailey Consulting , 5 * M % : ) ? 9 ) Copyright © 2008 Brian Bailey Consulting ) Qualification Steps Model phase Activate phase Report Static analysis of the design Report Analysis of the verification environment behavior Iterate if needed Detect phase © Certess, Inc. – 2008 Report Measure the ability of the verification environment to detect mutations , 1 7 9 7 ) : ) 7 7 ) Copyright © 2008 Brian Bailey Consulting , " ( ) * D # 5 N ' ! O # , ) % P F # ) % G # E ' ) E O % Copyright © 2008 Brian Bailey Consulting F ( -+. / 0 Q 0 120 1 0 # 0 ,R K DR << " / / / S/ 4 5/ 3# && 67#63# " 8& 67#94 8& 67#94 ! # QG QGK DR %0 R %/ & D& QGK HR << Q Q K DR S/ %0 R %/ & D& Q K HR R 34 "0 * 12 && 67#63# " 8& 67#64 ! 4 4 <299:9= 1 && 67#63# 8& 67#64 K 4 0 R 0 R ;/ 4 # & / # " 3:6;#94 / > A#?0 > %& /> 0 !4 3# 0? @ 0 34 :@ Copyright © 2008 Brian Bailey Consulting A # A# # )0*DTHR - Copyright © 2008 Brian Bailey Consulting ! # # ! ( Q << * ,R K DR QG QGK DR S/ %0 R %/ & D& QGK HR << ) ) << << =J K DR S/ %0 R K HR << L= << Q Q K DR S/ %0 R %/ & D& Q K HR R 0 R * ! -+. & # / " B 3:67#94 0 R ! / > A#?0 ! %&& /> 0 3# 0? @ 0 34 :@ Copyright © 2008 Brian Bailey Consulting A # A# # Global Metric Representing the overall quality of the Verification Environment ST reference : 75%, but usually higher Activation Score Measures the ability of the test suite to exercise all the RTL of the IP Similar to code coverage ST reference : 95%, & 100% explained Missing % should deeply studied & fixed or explained Propagation Score Measures the ability of the test suite to propagate mutations to the outputs of the IP ST reference : 80%, but should probably be enhanced by adding more test scenarios to reach 90% Detection Score Measures the ability of the environment to catch errors ST reference : 90%, but usually higher DAC’2008 - Anaheim : # 7 • Case study 1: • • • • Activation Score (A/F) Application: 3rd party IP HDL Directed Environment ~300 tests, 30 minutes Code Coverage ~100% Detection Score (D/P) • IP Activation Score (A/F) Propagation Score (P/A) Global Metric (D/F) Detection Score (D/P) 95% 90% 85% 80% 75% 70% 65% 60% ST Ref ST Avg 3rd Party IP 95% 97% 97% 80% 90% 80% 75% 80% 66% 90% 93% 85% Propagation Score (P/A) Challenges • • Convince 3rd Party IP provider High revenue, high visibility chip; reduce respin risk ST Ref ST Avg 3rd Party IP Global Metric (D/F) • Results • • Helped us to push IP provider to improve verification environment • and monitor progress Low detection score highlighted manual waveform checks DAC’2008 - Anaheim : # 7 ! ( # ( % # 51 % 9 Copyright © 2008 Brian Bailey Consulting - C 7 ) # '+# ) ) , . : 4 ) 5 % Copyright © 2008 Brian Bailey Consulting +! D , * Q S ( * OHNPN F!!G * OHNFONPH!H . *