In the 1990s, software developers were established users of software configuration management (SCM) tools such as open source RCS/CVS or of commercial systems such as Clearcase. Hardware designers, however, managed design data in ad hoc home-grown ways. ClioSoft’s founder, Srinath Anantharaman, recognized that hardware development could benefit from some of the same techniques and methods as software development., Hardware design flows had some unique requirements not met by SCM tools and hardware designers were not as comfortable with Unix command line tools. Anantharaman wanted to fill this gap by creating a hardware configuration management (HCM) system that would help streamline hardware design teams just as SCM tools had done for software teams.
ClioSoft was launched in 1997, as a self-funded company, with the SOS (Save Our Software) design collaboration platform as its first product to help manage front end RTL flows. With the commercial deployment of the tool, ClioSoft soon realized that the greater need was to manage design data from analog/mixed-signal designs where Cadence Virtuoso® was the dominant flow. Designs were created using graphical tools like schematic or layout editors that produced large collections of binary files. Designers worked at the abstraction levels of libraries, cells, and views and were not familiar with the physical files created by the design tools. It would have been really difficult to use a file-based management method to manage Cadence Virtuoso data. ClioSoft joined the Cadence Connections™ program in 1998 and proceeded to work closely with Cadence to solve this problem. The result was a new product, SOS viaDFII, that seamlessly integrated the version control and design management features of SOS with the Cadence Virtuoso flow, allowing users of the Cadence Library Manager to manage revisions of schematics and layouts without worrying about the physical files.
Over time, the exponential increase in design complexity and shrinking market windows led to larger design teams. With increased globalization, design teams started getting distributed, recruiting the best talent wherever it was available. These dual forces increased the need for design management and efficient collaboration. To meet the new challenges, ClioSoft introduced the cache server in 2002. A cache server could be run at the remote sites to automatically cache the latest file revisions and serve these files to the users at the remote sites without having to get the data from the primary site. This made working at remote sites almost as efficient as working at the primary site and gave every engineer real time access to changes to design data without the requirement for a very high bandwidth connection.
As design team and design sizes grew, additional burdens were put on the already-stretched IT resources and staff at customer sites. File servers would run out of disk space and backups would never end. ClioSoft realized that much of the design data was being duplicated, since each engineer had entire copies of the design libraries in his or her workspace even though only a small portion of the design was being modified. Clearly there should be a way to avoid this duplication without taking away control of the workspace from the designer. ClioSoft solved this problem by introducing the capability to create workspaces with symbolic links into the cached revisions that already existed in the cache. Workspaces were now a lot smaller because most of the files were symbolic links to a file in the cache except for the few files the user was editing. ClioSoft cache server was now able to track how many users were using each revision of each file. It kept all revisions being used and automatically purged all unused revisions. The smart cache allowed optimum use of disk while still giving each user complete isolation and control of his or her workspace. This was widely adopted by design teams and now over 90% of design teams using SOS in the Virtuoso flow use workspaces with links to cache. This feature was a clear differentiator for ClioSoft as SCM systems created to manage relatively small text files did not support such optimization.
With software or digital front end design, engineers typically create design files using a text editor. So they are well aware of files created and which files should be checked in to the data management (DM) system. This is not the case with analog and custom designs where engineers use graphical tools like schematic or layout editors that produce collections of files for each design unit (such as Open Access cell-views) – some of which should be managed together as a co-managed set and others that should not be managed at all. This is a crucial difference between hardware and software design data and ClioSoft handles this by managing co-managed files as a composite object that gets checked in as a single object. This preserves the integrity of the design data in each revision and clearly identifies and versions the design units as a whole and not as multiple individual files.
With the continued commercial success of ClioSoft’s HCM offering, there was a demand to support other flows from customers and other EDA vendors. Mentor approached ClioSoft in 2004 to provide DM for their ICstudio flow and a joint development effort resulted in SOS viaICstudio to provide integrated HCM for Mentor’s ICstudio. Having a data management solution had now become a de facto standard requirement for design teams. Customers requested that ClioSoft support a variety of different tools, including tools developed in-house. One of the big challenges in managing data from different tools is to understand and manage the right set of co-managed files while keeping it simple for the user. To solve this problem, ClioSoft introduced a rule-based technology called the Universal DM Adaptor. A CAD administrator can specify pattern-based rules that SOS uses to automatically package co-managed files into a composite object and exclude files that should not be managed. ClioSoft was awarded a US patent for this technology in 2010. Using this powerful and flexible technology, with encouragement from customers and active cooperation from major EDA vendors, ClioSoft soon had developed custom DM interfaces for SpringSoft’s Laker™ and Synopsys’ Custom Designer. ClioSoft now had a seamlessly integrated HCM solution for all the major analog and mixed-signal flows in the market.
As design teams got better at managing the design data, they wanted to reuse their IP from one design in other designs and derivatives. In 2008, ClioSoft introduced the Enterprise Edition that allows design teams to reference and reuse designs or IP blocks from different projects. The ability to assign custom attributes to design objects and the available SOS web browser interface provided easy intranet access to find and reuse IP blocks from across the enterprise.
A question that is asked very often during design is: “What changed?” It can be asked for many reasons – to review before committing changes, to pinpoint regression failures, to identify the design changes made for an ECO and for design reviews, especially before tape-out. Revision logs maintained by engineers are often of little or no help. Expanding beyond data management, ClioSoft launched the Visual Design Diff (VDD) tool at DAC 2010 to answer this very important question. VDD was able to quickly identify and highlight changes between different versions of schematics or layouts even down the entire design hierarchy. The ease of use and the obvious ROI of VDD led to immediate commercial success even in companies using other DM systems.
ClioSoft’s customer base has grown steadily to allow the company to remain self-funded. Over 120 organizations trust ClioSoft SOS HCM to manage their design data. That customer trust has translated into similar confidence in ClioSoft among the major EDA vendors.
In September 2012, Cadence published the book Mixed Signal Methodology Guide, which assembles the collective wisdom of 13 experts from companies such as Boeing, Cadence, and Qualcomm and includes a chapter on data management for mixed-signal designs written by ClioSoft.
Mentor chose ClioSoft as the only commercial vendor to provide DM for their Pyxis™ Custom IC Design Platform design flow released in 2012. Similarly, Agilent chose ClioSoft as their DM vendor of choice for the Agilent Advanced Design System (ADS) design flow released in 2013.
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