Posted by Tom Borgstrom on January 21st, 2009
I thought I would break the ice on my first blog post here and tell you a little bit about myself and my history in verification. (well, it was actually not my thought but rather a suggestion from fellow blogger Karen Bartleson over at The Standards Game , that helped me break my writer’s block and get started on this…Thanks Karen!)
I verified my first design way back in 1990 when I was an ASIC designer at Matsushita in Osaka. My chip was a video image processor / system controller for a “TV Door Phone ”, and we were the first team to use this new-fangled VHDL language, logic synthesis and HDL simulation (anyone remember the Very Slow Simulator? ;). Top-down design was very cool back then, and I was able to run the same simulations (I don’t think we called them testbenches yet) against high level models, RTL and netlists. Analysis was quite a chore; I remember having to tape multiple 3-meter long waveform printouts up on the wall to really understand what was happening throughout a complete video frame. I also recall very long nights as we approached our tapeout date, trying to complete timing verification of our scan chains and wondering if we had missed any errors in the functional waveforms. In the end we taped out not when verification was complete, but when my boss said “time’s up!”. Sound familiar? In the end, the gate array came back and worked, apart from about half of the scan chains with hold-time violations. We finished the entire design, from concept and tool selection to working first-silicon in a year. Top-down design was declared a success!
I then joined the EDA industry with a variety of startups, focusing on DFT, design services, FPGA synthesis, code coverage and functional verification until joining Synopsys five years ago to focus on testbench languages, tools and methodologies.
One of the interesting things I’ve observed over the past few years is how complex verification has become. Million line testbenches? Object-oriented programming? It seems like you have to be a software engineer to do verification anymore. But, without constrained-random testbenches, powerful debug environments and very fast simulators I can’t imagine how anyone could verify a modern chip – certainly not by taping waveforms on the wall and hoping you didn’t miss anything! “Hope ” may be a mantra for the new Obama administration, but I don’t think it’s the best way to verify your design!
And it’s just not about digital simulation anymore. Chips have really become Systems on Chips, with mixed signal blocks, multiple embedded processors, 3rd party IP, lots of embedded software and globally-distributed design teams becoming the norm for most designs, rather than the exception. How to efficiently verify these super-complex chips and systems from both a technology/methodology perspective and an organizational/economic perspective is what I’m interested in now, and what I look forward to writing about in the coming months.
Until then, keep your eye On Verification!