Xilinx, Inc.

Victor Slonim

Salim Abid

Parivallal Kannan

Guenter Stenz

Srinivasan Dasasathyan

Rajat Aggarwal

A method of placing input/output blocks on an integrated circuit device is described. The method may comprise receiving a circuit design having a plurality of input/output blocks to be placed at input/output sites of the integrated circuit device; modifying, for each input/output block of the circuit design, an input/output standard for the input/output block to include bus information; assigning, for each input/output block of the circuit design, an input/output site for the input/output block; and generating an input/output placement for the input/output blocks of the circuit design. A computer product is also disclosed.

Method of placing input/output blocks on an integrated circuit device

A method of assigning a plurality of input/output (I/O) objects of a circuit design to banks of a programmable integrated circuit (IC) using integer linear programming can include storing a plurality of constraints that depend upon a plurality of variables, wherein the plurality of constraints regulate assignment of each of the plurality of I/O objects to banks of the programmable IC (-), and storing a linear function that depends upon the plurality of constraints and a plurality of cost metrics, wherein each cost metric imposes a penalty when a selected I/O object of the circuit design is assigned to a bank of the programmable IC that is different from a bank to which the selected I/O object is assigned within a reference solution that is infeasible (). A result indicating whether a feasible solution exists for assignment of the plurality of I/O objects of the circuit design to banks of the target programmable IC can be determined by minimizing the linear function () subject to the plurality of constraints and outputting the result ().

Assignment of select input/output blocks to banks for integrated circuits using integer linear programming with proximity optimization

A method of input/output (I/O) block placement assigned to an input/output bank includes formulating a placement algorithm using integer linear programming (ILP) and simultaneously placing single groups and Relatively Placed Module (RPM) groups of I/O blocks in the I/O bank. The method further includes determining a placeability matrix P and a binary assignment matrix X used for the ILP. The method can further eliminate all assignment matrix elements of X equal to 0 in the integer linear programming and re-index any remaining elements. The method can further place all I/O blocks according to a solution if solving of the standard ILP formulation results in a feasible solution. Optionally, the method generates a placement solution that is as close as possible to an external reference solution specified by designer. Optionally, the method analyzes which constraints were violated and generates useful error information.

Placement of I/O blocks within I/O banks using an integer linear programming formulation

A method of assigning input/output (I/O) objects of a circuit design to banks of a target device using integer linear programming can include assigning the I/O objects of the circuit design to I/O groups according to compatibility among the I/O objects, and establishing a plurality of relationships, comprising measures of bank capacity, regulating assignment of the I/O objects of I/O groups to banks of the target device. Each measure of bank capacity can indicate a maximum number of I/O objects from a selected I/O group that can be assigned to a selected bank of the target device. The method also can include determining whether a feasible solution exists for assignment of the I/O objects of the circuit design to banks of the target device by minimizing an object function while observing the plurality of relationships.

Assignment of select I/O objects to banks with mixed capacities using integer linear programming

A method of assigning I/O objects to banks of a target device can include concurrently assigning I/O objects, including select I/O objects and clock I/O objects, of the circuit design to I/O groups according to an I/O standard associated with each I/O object. Each I/O group can include only I/O objects of a same I/O standard. The method also can include establishing a plurality of linear constraints for regulating assignment of the I/O groups to banks of the target device. The linear constraints can include range constraints indicating I/O banks capable of hosting clock I/O objects. The method also can include defining mutual relationships among selected ones of the linear constraints. An indication as to whether a feasible solution exists for assignment of the I/O groups to banks of the target device can be provided by minimizing a linear objective function while observing the linear constraints and the mutual relationships.

Simultaneous assignment of select I/O objects and clock I/O objects to banks using integer linear programming

A method of global clock placement for a circuit design to be implemented on a programmable logic device (PLD) can include identifying clock properties for the circuit design and identifying physical clock region attributes for the PLD. The method further can include specifying an Integer Linear Programming formulation (ILP) of a clock placement problem for the circuit design from the clock properties and the physical clock region attributes. The ILP formulation can be solved to determine whether a feasible clock placement exists for the circuit design.

Method of flexible clock placement for integrated circuit designs using integer linear programming

A method of input/output (I/O) assignment for a circuit design for a programmable logic device (PLD) can include determining I/O types for I/O objects specified by the circuit design, defining a plurality of virtual I/O bank-groups, wherein each virtual I/O bank-group includes at least one virtual I/O bank, and binding I/O objects of the circuit design into I/O groups according to the I/O types. A binary compatibility matrix can be created. The binary compatibility matrix can indicate the compatibility between the virtual I/O bank-groups and the I/O groups based upon the I/O types of I/O objects within each I/O group. A determination can be made as to whether a feasible solution exists for I/O assignment of the I/O objects of the circuit design according to a plurality of constraints and the binary compatibility matrix.

Assignment of I/O objects with multiple I/O standards to virtual I/O banks using integer linear programming

A method of physical design for a programmable logic device (PLD) can include associating movable objects of the PLD with a criticality measure that is dependent upon timing information for a configuration of the PLD (). The method further can include calculating the criticality measure for each movable object () and calculating a probability for each movable object (). The probability can depend upon the criticality measure for the movable object. The method also can include selecting one or more of the movable objects for controlled move generation within a simulated annealing process (). Movable objects are selected for controlled move generation according to the probabilities assigned to the movable objects.

Cost-independent criticality-based move selection for simulated annealing

A method of physical design for a programmable logic device can include associating target locations for movable objects with criticality measures and calculating the criticality measure for each target location. A probability for each target location can be calculated. The probability of the target location can be dependent upon the criticality measure for that target location. The method further can include selecting a target location for one of the movable objects for controlled movement during a simulated annealing process. The target location can be selected according to the probability corresponding to each target location.

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Broomfield, CO, United States of America

Victor Slonim