A Hardware and Software Monitor for High-Level System-on-Chip Verification M. El Shobaki and L. Lindh International Symposium on Quality Electronic Design, 2001 Presenter: Gu, Ruei-Ting
What s the problem? As the complexity of SoC designs grows, it s important to move verification to higher abstraction-level (System-Level). System-Level Few events Gate-Level RTL Target System Many events 2/13
Outline Why the verification process need to take place at the system level? The proposed mechanism Experiment example Summary 3/13
Why system-level verification The SoC design complexity is increasing To verify a whole system using computer model simulation is time consuming Hardware/software co-simulation? It s not sufficient! 4/13
How to verify at the system-level Original idea: Software Monitors In RTOS (Real-Time Operating System) Provides process-level info» Task scheduling events» inter-process communication events» External interrupts, etc. The drawback of Software Monitors It s required to instrument the S/W with special monitor instructions The instrumentation utilizes target resources» Memory space, execution time from the CPUs 5/13
The proposed approach MAMon (Multipurpose/Multiprocessor Application Monitor) mechanism: A hardware-based monitoring system Make a SoC observable at different abstraction-levels both in H/W and S/W Advantages of MAMon Process-level events can be monitored without S/W overhead With no instruction on the system s timing behavior 6/13
MAMon overview The proposed monitoring system, called MAMon Probe Unit: HDL code Events database, Waveform graph tool 7/13 Events: 1. An access of a SoC IP 2. A certain condition on a bus (address, data, ) 3. An interrupt assertion, etc.
The Probe Unit Event Detector: Performs conditional comparisons (comparator) on input signals. On-chip memory buffer: Store the detected events (Event-sample format) 8/13
Host interface Host communication interface: Bi-directional Enhanced Parallel Port 9/13
The tool environment The tool environment provides the user to view and search the event samples received from PU The received data must be stored in filestructures that are optimal for searching 10/13
MAMon s tool environment Event-graph tool Displays portions of the event history Event-filter tool Used to hide excess information, and also can reduce the search-space 11/13
An example Monitoring a H/W-based RTOS kernel. RTU: Real-Time Unit For increasing RTOS performance Used as the single RTOS for both single- and multiprocessor systems No additional monitoring S/W is required on the target. 12/13
Conclusions On-chip support for monitoring and debugging is critically important. Traditional solutions can not keep pace with today s system speed, Limited pinouts in chip-packaging, and Difficulties in reaching the physical pins The MAMon mechanism On-chip monitoring and debugging in RTL and system-level, Non-intrusive and synchronous 13/13