Cadence Design Systems, Inc.

Yuhei Hayashi

Mitchell Grant Poplack

Beshara G Elmufdi

Hitesh Gannu

Mark Alton Sherred

An emulation processor may be configured to support emulating unknown binary logic based on non-arbitrariness of the unknown binary logic. For example, an unknown binary logic signal may take the finite binary values of 0 and 1. The circuitry in the emulation processor is configured to generate and propagate outputs based on the interactions of known input binary signals with the unknown input binary signals having non-arbitrary states. The emulation processor may support the both combinational and sequential operations associated with the unknown binary logic.

Emulation system supporting representation of four-state signals

Embodiments disclosed herein describe systems and methods for tuning phases of interface clocks of ASICs in an emulation system for a low latency channel and to avoid read errors. During a bring-up time (e.g., powering up) of the emulation system, one or more training processors may execute a software application to iteratively tune the phases of the interface clocks such that data is written to the interface buffers prior to being read out. To mitigate the problem of higher latency, the training processors may execute software application to tune the clock phases such that there is a small time lag between the writes and reads. The training processors may set the time lag to account for factors such as memory setup and hold, clock skews, clock jitters, and the predicted margin required to account for future clock drift due to carrying operating conditions.

Architecture and methodology for tuning clock phases to minimize latency in a serial interface

Emulation system supporting computation of four-state combinational functions

A pseudorandom logic circuit may be embedded as a hardware within an emulation system, which may generate pseudorandom keephot instructions. A masking logic may mask out portions in each pseudorandom keephot instruction, which may change state elements during execution. A cluster of emulation processors may execute masked pseudorandom keephot instructions to consume power when not executing mission instructions. The cluster of emulation processors may run keephot cycles, during which the cluster of emulation processors may execute the pseudorandom keephot instructions causing the cluster of emulation processors to continue consuming a roughly constant amount of power, either at a same or different voltage level, but supposed outputs of the pseudorandom keephot instructions may have no impact upon inputs and outputs generated during mission cycles.

Pseudorandom keephot instructions to mitigate large load steps during hardware emulation

The embodiments disclosed herein describe a switching ASIC that provides a dynamic single-bit routing and multiplexing function in an emulation system. The switching ASIC may receive a set of incoming data streams from a first set of emulation devices (e.g., emulation ASICs), disassemble each data stream to the constituent bits, dynamically multiplex the bits, reassemble the multiplexed bits into outgoing data streams, and transmit the outgoing data streams to a second set of emulation devices. Multiple statically scheduled selection tables (UCSWs), one for each output lane of the switching ASIC, drive the selection and routing of bits from input slots of various input lanes to the output slots of the output lane.

Dynamic one-bit multiplexing switch for emulation interconnect

Using a framing protocol, an application specific integrated circuit (ASIC) in an emulation system may transmit a start-of-packet molecule to a serializer-deserializer (SerDes) interface of a switching ASIC in a gap cycle leading up to an emulation cycle such that the switching ASIC may start routing mission data through the SerDes interface during the emulation cycle. The ASIC may transmit an end-of-packet molecule at a first gap cycle to the SerDes interface of the switching ASIC such that the switching ASIC may stop routing data through the SerDes interface during the gap cycles. The start-of-packet molecule may include a start-of-packet word, a status word, cyclic redundancy check word, and an idle word. The end-of-packet molecule may include an end-of-packet word, a status word, a cyclic redundancy check word, and an idle word.

Framing protocol supporting low-latency serial interface in an emulation system

Emulation system supporting four-state for sequential logic circuits

A compaction circuit in an emulation system may store in a data array emulation data that may be read in subsequent emulation steps. For each emulation step, the compaction circuit may receive keeptags from a local control store word of the emulation step and store portions of emulation data identified by the keeptags. The keeptags in the control store words may be inserted by a compiler based upon whether a corresponding read port of emulation processor reads the stored data in the subsequent steps. The compaction circuit may also translate the logical read address of the stored data to a physical read address in the shared data array. A dynamic modification engine may enable dynamic modification of netlists while using the compacted data array. In response to a request, the dynamic modification engine may modify one or more keeptags and update read addresses in the control store words.

Systems and methods for emulation data array compaction

Dynamic netlist modification of compacted data arrays in an emulation system

An emulation system may have a built-in self-test circuit to generate one or more built-in self-test instructions. The one or more built-in self-test instructions may be pseudorandom. The one or more built-in self-test instructions may cause one or more emulation processors of the emulation system to generate one or more deterministic outputs. A testing processor of the emulation system may compare the one or more deterministic outputs to detect a faulty emulation processor, a faulty emulation processor cluster, or a faulty emulation chip of the emulation system.

Functional built-in self-test architecture in an emulation system

Disclosed herein are systems and methods of compiling resources of a programmable emulation system to execute an emulation process, to emulate a logic system, such as an application-specific integrated circuit (ASIC), currently being tested and prototyped, and then revising, transforming, and moving the compiled instructions sets to inexpensively, quickly, and dynamically adapt to unavailable resources, which may be due to previously allocation to a different emulation job, or for fault tolerance. Relocation of the resources that will execute the emulation job (i.e., 'footprint') may refer to the remapping of a compiled footprint to a revised set of resources, defining a revised footprint. Fault tolerance may refer to support for working around faulty hardware components of the emulation system.

Data routing and multiplexing architecture to support serial links and advanced relocation of emulation models

Disclosed herein are systems and methods to generate, by a compiling processor, one or more sets of one or more execution instructions responsive to compiling a netlist file. The method further includes storing, by the compiling processor, a set of execution instructions into an instruction memory of an execution processor. The method further includes generating, by a compiling processor, a set of one or more keephot instructions for the execution processor based upon the set of execution instructions stored into the instruction memory of the execution processor. The method further includes storing, by a compiling processor, the set of keephot instructions into the instruction memory of the execution processor.

Method and system to mitigate large power load steps due to intermittent execution in a computation system

A control-circuit of an emulation system may include one or more serial link inputs communicatively coupled to a serial bus, a serial link input receiving an input control bit from the serial bus. A configurable logic circuit may be configured to receive multiple control bits from the one or more serial link inputs, execute one or more operations on the plurality of input control bits according to programmable logic, and transmit an output control bit to a serial output link.

Enhanced control system for flexible programmable logic and synchronization

Systems and methods of emulating application-specific integrated circuits using multiple execution phases, where different inputs and outputs are used or produced by components of the emulation system are disclosed. For example, an OMUX may select and transmit different data over a serial bus based on the execution phase of the emulator system. In another example, a processor or cluster may capture outputted data during a first execution phase, execute instructions for a second execution phase, and then return to the capture outputted data for further processing during a next cycle of the first execution phase.

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San Jose, CA, United States of America

Yuhei Hayashi