A protocol VIP agent contains: sequencer (generates transaction-level stimulus), driver (converts transactions to pin activity), monitor (observes pins and reconstructs transactions), and checker (validates protocol rules on observed transactions).
Passive VIP monitors bus activity without driving. Active VIP drives and monitors. Use passive at chip level where real masters exist; active at block level where you need stimulus.
UVM PROTOCOL AGENT
sequencer --> driver --> DUT pins
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monitor <--- DUT pins
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+--> checker (protocol rules)
+--> coverage (bins)
+--> scoreboard (if connected)A VIP pass means its enabled checkers observed no violation for the monitored signals, interval, configuration and assumptions. It does not by itself establish unobserved protocol behaviours, functionality, the system address map, firmware configuration or cross-interface ordering.
A block-level pass followed by a chip-level failure means the existing evidence did not cover the failing condition. Compare boundaries, configuration, traffic, resets, clocks, power states, bridges and reference-model assumptions before calling it an integration gap or a VIP defect.
Configure VIP to match implemented spec version and feature subset.
VIP parameters (data width, ID width, outstanding depth) must match DUT.
Choose active or passive roles from who owns stimulus at that boundary; chip-level environments can use either when the connection and ownership contract permit.
Configure VIP to match implemented spec version and feature subset.
VIP parameters (data width, ID width, outstanding depth) must match DUT.
Choose active or passive roles from who owns stimulus at that boundary; chip-level environments can use either when the connection and ownership contract permit.