Software entity for the creation of a hybrid cycle simulation model

• US 7,987,086 B2
• Filed: 10/10/2008
• Issued: 07/26/2011
• Est. Priority Date: 09/12/2005
• Status: Expired due to Fees

• Current Assignee: GlobalFoundries, Inc.
• Original Assignee: International Business Machines Corporation
• Inventors: Huston, Elspeth Anne, Kamindki, Edward J. Jr., Van Huben, Gary A.
• Primary Examiner(s): Phan; Thai
• Application Number:
  US12/248,951
• Publication Number:
  US 20090030666A1
• Time in Patent Office: 1,019 Days
• Field of Search: 703/16, 703/22, 703/23, 716/106, 717/131
• US Class Current: 703/16
• CPC Class Codes: G06F 30/33 Design verification, e.g. functional simulation or model checking

Abstract

Disclosed is a software entity for constructing a Hybrid Cycle Simulation model comprising Compiled Data Units (CDUs) for use in design verification. The simulation model may contain a plurality of 1-cycle CDUs, optimized for simulation throughput, and 2-cycle CDUs, optimized for simulation accuracy, or a mixture thereof. Utilizing a netlist tool extracting hierarchical design source components for use, the construction checks that all inputs and outputs of any hierarchical design source components bind, and employs Object Traversal Directives for incorporating the selected CDUs into the simulation model. A data management method is used for tracking the validity of the components in the model. Additionally, a software entity (FACDDR) permits high bandwidth simulation of design components normally requiring cycle accurate simulation. FACDDR provides linkages for standard logic elements for abstracting one or more design interface components out of a cycle simulation environment and design interface emulation of an interface which interacts with a cycle simulation model through an API to extract present value of driving side signals of an interface and to set the cycle simulation model on the receiving side.

Claims

1. A software entity embodied in non-transitory tangible media for use with a digital design simulation model, comprising:

linkages for standard logic elements for abstracting one or more design interface components out of a cycle simulation environment constructed with a cycle stimulation model in which all design source components are compiled into 1-Cycle CDUs, all design source components are compiled into 2-Cycle CDUs, or design source components are compiled into a combination of 1-Cycle and 2-Cycle CDUs , and

wherein is included a merge and build step wherein said combination of 1-Cycle and 2-Cycle CDUs are incorporated into a flattened cycle simulation model comprised of internal data structures representing low level primitive blocks thereby producing a cycle simulation model containing a mixture of 1-Cycle and 2-Cycle CDU representation of design component source,

design interface emulation of interface which;

(a) interacts with a hybrid cycle simulation model through the use of an API to extract the present value of the signals at the driving side of an interface, and

(b) sets facilities within said hybrid cycle simulation model on the receiving side of the interface, and

wherein said software entity'"'"'s control data and control code consists of information about delays, the mode that determines what facility accesses and alterations should be performed by the software entity, and a description of which bits of which wires and registers should be connected via an Application Program Interface for manipulating and accessing data pointers which represent a plurality of driver registers, receiver registers and bus interfaces, and further provides one propagation delay to the first part of a data transfer corresponding to a first clock edge and a same or different propagation delay to a second part of a data transfer corresponding to a second clock edge for use in a double data rate interface.

2. The software entity according to claim 1 wherein said software entity permits said present value to be transferred from the driving side to the receiving side using the precise cycle propagation delay as dictated by design specification.

3. The software entity according to claim 1 including optionally setting the bus interface simulation facilities between the driving and receiving sides of the interface,

and further permitting said values to be transferred from the driving side to the receiving side using the precise cycle propagation delay as dictated by the design specification.

4. The software entity according to claim 1 wherein said software entity may optionally emulate the boundary driving and receiving registers on both sides of an interface for situations when the interface logic is not available for incorporation into the verification model.

5. The software entity according to claim 1 wherein the software entity interacts directly with actual driving and receiving boundary registers in cases where the actual interface logic is incorporated into a simulation model.

6. The software entity according to claim 1 wherein said software entity provides an Application Program Interface (API) to permit a plurality of simulation environments to utilize the software entity to interact with the underlying design components or with any software elements employed to represent one or more of said interface components for purposes of imparting and/or monitoring the transfer of data packets across an interface using prescribed interface propagation delay as defined by a design interface protocol.

7. The software entity according to claim 1 wherein the software entity provides virtual facilities to substitute for the boundary driver and receiver registers to manipulate and/or monitor an interface when said driver and receiver logic has not yet been incorporated into the verification model and wherein said virtual facilities can be optionally used or ignored at which time the logic design becomes available for use in said verification model.