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Daily Scribble

DAC 2010 Technical Report (Day 1)

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Today is the report of my first day in DAC. I signed up to a full day technical workshop Choosing Advanced Verification Methodology. After the workshop ended at 3:30p, I managed to checked out a few companies in the exhibition floor Vennsa Technologyies, Agnisys Inc and Veritools

Advanced Verification Methodology

The workspace is smaller than I expected. There is only about 20 attendants. It started off with a keynote from Brian Bailey, a verification consultant, on the latest trends in verification. Assertion and ESL seems to be the theme of the day.

We finally see formal verification comes out from academic research and put into use by the industry and developing a good use model. There are 7-8 formal tools venders in the market right now, but looking at historical data in the EDA industry, no matter what previous technology, the market is only big enough for 2 to survive.

ESL is the latest buzz word. The word has many different meaning but basically it means where software and hardware comes together. To verification, ESL means we are building reusable testbench with different abstraction layers. Starting from the top with TLM model to verify the algorithm, then push down to verify the architecture, and then the RTL implementation at the very bottom. TLM 2.0 is the new industry standard and pretty much sweep aside all proprieties prototypes from different vendors. TLM 2.0 still lacks synthesis and no hardware/software interface.

Currently, many people model ESL in SystemC, but both SystemC and System Verilog need a few more revision to fully support ESL. The new ANSI concurrent C/C++ coming out this year many turn SystemC into a obsoleted branch of C/C++. High-level synthesis, C to RTL compiler, is almost an ESL enabler. It separate the architecture from behavioral description. The shift from RTL coding to high-level synthesis would be as disruptive as the shift from schematic capture to RTL coding.

Constraint random generation is a challenge in ESL verification. Current tool does not understand sequential depth and can’t constraint across sequence. Functional coverage is broken. It is merely isolated observation not necessary reflect the verification progress. We need a different metric to provide a direct measure on verification closure.

In ESL development, management will be a new challenge. Now we have to develop the hardware and software in the same development cycle, there will be conflicting schedule between the hardware team and the software team. Communication among different team and clear interface management at the partition between software and hardware implementation is the key.

In the next few years, the speak predicts there will be more research and probably technology break though in these areas: specification capture in verification, sequential equivalent checking, intelligent testbench, assertion synthesis and behavioral indexing.

After the keynote session, it is customer panel. The panel guests are Intel, ARM and nVidia. The ARM and nVidia are assertion expert, the Intel guy is more on ESL. It is Q&A session, but nothing special, the guest only talks about very generic things. They tell us what they do but don’t they us how they do it.

Jasper has the next presentation together with nVidia and ARM gives customer testimony. They talked about their formal verification tool and introduce basic concept like full proof, counter example, partial proof. There are quite a few neat examples of formal verification, like generate an input sequence for a given output trace, answer urgent customer question on whether something is possible in the design, verify dead lock/live lock, checking ‘X’ propagation. Both ARM and nVidia has dedicated assertion team and they said that is important to the success in using assertion in verification.

Synposys presents new updates to VCS simulation. They close the coverage to constraint loop with the Echo testbench technology. It is similar to what Cadence has and it is limited to the coverages that has a direct relationship to the constraint VCS finally has multi-core support. I think Cadence already it in IES 8.2. We should look into using both technologies for Digi. We should work with the CAD group to set up special LSF machines reserved for multi-core jobs.

TSMC talk about its Open Initiation Platform (OIP) for ESL verification. The virtual platform enable hardware/software co-simulation. The testbench is build from the top-down approach. Start with ESL TB to verify the algorithm, then ESL SoC TB to verify the ESL mode, then add cycle accurate adapter to the ESl model and finally the RTL testbench.

Mentors talks about ESL testbench and present a success story of TLM to RTL synthesis verification. They claim the high level synthesis flow save them lots of time and use the same testbench with different abstraction from top to bottom.

There is nothing new in Cadence’s presentation. They just show how vPlan fit in ESL flow.

Vennsa Technologyies
It is a small company in Toronto based on the research of a prof. from U of Toronto. Their OnPoint debug tool is pretty neat. It is an add-on to the simulation help the designer pin point the bug. Once you have an assertion failure, you can fire the OnPoint GUI. The tool will back trace the logic cone, narrow down and suggest where the bug is about. You can also start the back trace from a given value on the output pin at a given time. I played their demo for almost half an hour and it is a very handy tool if it works as advertised. The idea behind the tools sounds and I think we should evaluation the tool.

Agnisys Inc
This company has two product: IVerifySpec, a web GUI replacement for vManager and iDesignSpec, a half bake solution similar to RDA.

IVerifySpec use SQL database to store the vPlan, but it does not support UCD directly. It has to translate the UCD to an XML offline and import to the database. There is a few nice feature in the GUI, like heat map, traceability matrix, some charts and graphs looks like Google Analysis. However their tool is very immature overall, it does not support multi-level hierarchy in requirement specification, no revision control and data entry via the web interface is very tedious and user unfriendly. I should simply ask Cadence copy those nice report feature into vManager.

iDesignSpec sounds good on paper but the implementation is awkward. You enter the register specification in Word using some funny plug-in. Then the plug-in will generate PDF, HTML, XML, VHDL, OVE, C++ files. Somehow it is the exact opposite of our RDA flow. We enter our register description in XML and generate one thing at a time using scripts. The format of their word plug-in is very ugly. The code and PDF file generated by the plug-in is very primitive. I would say even our old ECBI generator is better than this tool. The only thing useful I learn from this presentation is there are industry standard for register description, SystemRDL and IP-XACT. Maybe our RDA tool should support industry standard as well.

Veritools

Their flag ship product is Veritools Designer. It’s basically a Debussy Verdi clone. It can view schematic and waveform, source code debugging. They claim their tool is very fast and only cost 1/4. I am always skeptic about those claims and I don’t like they use a their own waveform database format. It means simulator has to dump another waveform through their PLI. The GUI is fast but the design in the demo is not very big. The GUI is quite primitive compare to Simvision and they can’t beat the price of Simvision which comes free with IES. I do agree Simvision is a bit slow but I think investing in faster computer with bigger RAM can solve this problem. They have an add-on tool called Veritool Verifyer. This tool is kinda dumb. If there is an assertion failure, it read in the waveform and let you to test changes to the assertion code without invoking the simulation. I don’t think it is very useful. When an assertion fail, how often it is due to RTL bug and how often it’s just a faulty assertion?

Daily Scribble

DAC 2010 – First Impression

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This is the first time I am going to the Design Automation Conference (DAC) conference or any industry conference. It is really an eye opener for me. When I first started working in PMC during the dot-com bubble days, the company promised send us to a conference every two years. Unfortunately before my turn to go, the bubble burst and the company is on survival mode for almost a decade. Finally, we are back on the growth track and the company has money to invest in developing the employees and budget to send us to industry conference.

There is a few reason I picked DAC to go. First, it is the biggest conference of the EDA industry. It has 3 days of exhibition and 2 more days for tutorial and workshops. You can see everything under the same roof, all the tool venders, 3rd party IP provider, the big names and new start up that you never heard of. Second, there are many workshops and tutorials sessions specified for verification, so I can learn what’s new other there, what other companies are doing. In fact there are so many interesting sessions that I could not see them all. Last, the conference is in Anaheim, right next to Disneyland. I am flying Pat down here and spend a weekend after the conference as a mini-vacation.

The latest technology presented by the exhibitors are amazing, but I am equally amazed by the registration system. After you have registered on-line, you can pick up your badge in the registration desk. The process is very smooth, just scan the bar code and your card is printed right in front of you. The card has built in RF chip. You no longer have to hand out business cards to exhibitors, they have a cell phone like device scan your card and print out your information automatically.

There are lots of freebies in DAC. It’s only the first day of the exhibition, I only covered 1/3 of the exhibition and I already got the following freebies: 1 backpack, 3 T-shirts, 4 balls, 2 highlight pens, a measuring tape, A battery powered cell phone charger, a pair of waist band and a book “The ten commandments for effective standards”. Other than freebies, there is free beer. Last night we have the kick-off reception sponsored by Intel. Tonight I went to the Denali party in Disney Downtown. Although, there is the beer is bottomless, no one is abusing the kind offer and got drunk. It is an industry conference after all, you don’t want to embarrass yourself in front of potential clients and employers. The industry is a small world after all.

I am looking forward to the rest of the week. I am going to write about what new technology I learn in DAC every day. Stay tuned.

Daily Scribble

Sears Stars on Ice

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I have watched figure skating on TV during the Olympic games, but it is the first time I am watching live figure skating. Olympic figure skating ticket is too expensive, Sears Stars on Ice features Olympic figure skaters, like Joanna Rochette, and a it only cost $45. The skaters seems more relax in the show than in the competition. I suspect they are saving their best for the competition and I only get to see the safe moves.

I never watched figure skate seriously, I have only watched the highlight on TV. Watching a live show confirmed my belief that figure skating is boring. The first few skaters are fun to watch, but soon the novelty wears off. The movements of all skaters are more or less the same, they are just jumps, turns, spins, throws in different sequence. Watched one pretty much watched them all. The most noticeable difference among the skaters is some of them screwed up the landing and lost their balance. Figure skating is so boring that I slept thought the second half of the show.

Sports, like figure skating, with no objective measure of winners and losers are usually boring. It relies on subjective measurements like aesthetic appeal of the judges to determine the outcome, so you don’t get any excitement out of competition. In sports with objective measure, it is easy to understand the athletes, as their action are directly related to winning the game. However in sports without objective measure, the athletes’ actions do not have obvious purpose and the sport lost its meaning, thus it is boring.

Daily Scribble

The 5th Bangalore Trip

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This is my 5th trip to Bangalore. Instead of staying in the guest house, this time I am staying in a new hotel in Electronics City, which is only 5 minutes walk away from the office. When I first went to Bangalore 2 years ago, there wasn’t any business hotel close to the office, but now at least 4 new hotels has opened. My hotel is acceptable, but there are still many little things that drive me nuts in the usual Indian way. For example, the room has a do not disturb light outside of the room, but somehow the room service always ignore the sign. They will ring your door bell at 7:30a giving you your morning newspaper, then ring your door bell again at 8:00a asking you whether you have laundry for the day. Like a typical business hotel, the room comes with a comfortable bed and a large working desk, but they don’t have any lights over the desk. I have to move a pole light from other side of the room to light up the desk area. For whatever stupid reason, the hotel decide only to turn on the boiler from 6a-10a and 6p-10p, if you want to take a shower in the afternoon or at night, sorry you only have cold water. Given that most flight arrive India after midnight and almost every traveler want to take a hot shower the first thing after checking into the hotel, it leaves a very bad first impression. I swear I will never go back to this hotel again.

Bangalore has changed a lot since my first visit 2 years ago. The toll bridge linking Electronics City to Bangalore is finally open. Now it only takes 15 minutes from the office to Forum Mall, compare to over 45 minute in the past. Taking the bridge costs Rs45 a day, saving 30 minute for $1 definitely worth the price. However, I suspect the bridge won’t last very long. They forgot to build proper rain drain system for the bridge. When it rains, the center lanes are floated with water as deep as a feet. The bridge opens for the first monsoon season and the pillers already shows signs of rusting and water damage. Our company even issue a warning to the employees warns them not to use the bridge during heavy rain.

Looks like the outsourcing business in Bangalore is doing well. I have met a lot more foreigner this time compare to 2 years ago. There are quite a number of German staying in my hotel and they work for different companies. We love to exchange Indian stories, whining how annoying some of the Indians are and we all agree it sucks living in Bangalore. There are many new non-Indian restaurants opened in last year, Japanese food is in fashion in Bangalore, with the number of Japanese restaurants tripled. Some 5 stars hotels start offer sushi at their Sunday lunch buffet. I am very skeptical about idea of eating raw fish in India, I don’t want to get any food poisoning in Indian. The the number of western restaurants is blooming but the quality of service is deteriorating. In the past the service was supreme, there is always a waiter available when you need one and they call the customers Sir or Madam. Now, maybe the restaurants is spoiled by western customers, their service is no difference from with what we get back home. Food and gloceries is still cheap in Bangalore, although there is an annual 20% pay increase in the high-tech industry, the rest of the people are still very poor.

I see more traffic lights and less cows on the road. The city seems to be less chaotic, I wonder it is just my illusion because I am getting use to the chaos. I hire a cab via the hotel to take me to nice restaurant every night as usual. Somehow the drivers are clueless about the address and they don’t know how to read Google map. To make sure I can dinner on time, I jumped to the front seat and navigate the driver. Since there is no street signs in Bangalore, telling you which street to turn is useless. Google map comes up with a solution, in addition to the street name it also list any landmark at the street corner. The driving instruction in Google map tells you turn right at KFC or BP gas station, pretty neat. I can’t wait to see Google street view comes to Bangalore.

Daily Scribble

Work-life balance

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When I talked to my friends who are working in HK, they often complain they don’t have any work-life balance. HK people probably has the highest average working hour in the world. It is not uncommon that people comes to work on 9am and work till 8pm to 10pm. No wonder when I ask them what they do outside of work, they pretty much does not much other than sleep or mundane brainless activities like watching TV, movies or shopping. It is because their have totally drained their energy at work.

Recently I feel like I am working in HK. The project is approaching the deadline, although my own tasks are in relative good shape, unfortunately an Indian team is on fire and I am parachuted to help them out. It’s not fun being in the hot seat﹐ especially when the upper management pays close attention on the schedule, you have to work with a team of Indian contractors who are not your direct report and some of them have the tendency of running on their own.

I tried to employ the chief programmer development model to speed up the development, but there is a major draw of this approach. The chief programmer has to keep up and stay on top of the team in order to have full control. If the team is located in the same physical location, it is much easier to communicate and direct the work. My team is 12 time zones from me, so I only have one chance to interact with them per day. Giving instruction via email is very inefficient because I have to make sure everything is very clear, if they got stuck they will have to wait another day for my response. I set up office hour every night to answer their questions, combined with early morning meeting and working late to keep up with their work, it really cut into my person time in the evening. I am so exhausted that I don’t even have energy to update my blog. I rather shut off my brain and watch some TV on the hour I manage to squeeze between dinner, wife-time and work. Now I understand why the life of my HK friends are so dull, because there is no work-life balance.

When my boss asked me to fly over to India fix thing up over there. I weight the lesser evils between travel to Bangalore a couple of weeks get things back on track or have conference call every night until project ends. I rather suffer a short period of time than drag on in a prolong period of pain. Well, think about the good side, I have 12 hours transfer in HK on my way to India, I can visit my grandma and go for some brief shopping.