Patents Represented by Attorney, Agent or Law Firm Casimer K. Salys
  • Patent number: 7664965
    Abstract: Multiple trusted platform modules within a data processing system are used in a redundant manner that provides a reliable mechanism for securely storing secret data at rest that is used to bootstrap a system trusted platform module. A hypervisor requests each trusted platform module to encrypt a copy of the secret data, thereby generating multiple versions of encrypted secret data values, which are then stored within a non-volatile memory within the trusted platform. At some later point in time, the encrypted secret data values are retrieved, decrypted by the trusted platform module that performed the previous encryption, and then compared to each other. If any of the decrypted values do not match a quorum of values from the comparison operation, then a corresponding trusted platform module for a non-matching decrypted value is designated as defective because it has not been able to correctly decrypt a value that it previously encrypted.
    Type: Grant
    Filed: April 29, 2004
    Date of Patent: February 16, 2010
    Assignee: International Business Machines Corporation
    Inventors: Steven A. Bade, Linda Nancy Betz, Andrew Gregory Kegel, David R. Safford, Leendert Peter Van Doorn
  • Patent number: 7657772
    Abstract: An integrated circuit having a temperature sensitive circuit (TSC) to generate a signal indicative of the substrate temperature near the TSC. The integrated circuit has circuitry configured to receive a TSC signal from at least one TSC and to convert the TSC signal to a signal indicative of the integrated circuit's temperature. The thermal control circuit compares the integrated circuit temperature to a threshold and produces a corrective action signal when the temperature exceeds the threshold. The corrective action signal is provided to corrective action circuitry preferably configured to modify the operation of the IC to reduce the IC temperature in proximity to the corresponding TSC.
    Type: Grant
    Filed: February 13, 2003
    Date of Patent: February 2, 2010
    Assignee: International Business Machines Corporation
    Inventors: Joachim Gerhard Clabes, Michael Stephen Floyd, Paul David Muench, Lawrence Joseph Powell
  • Patent number: 7603703
    Abstract: A secure communication methodology is presented. The client device is configured to download application code and/or content data from a server operated by a service provider. Embedded within the client is a client private key, a client serial number, and a copy of a server public key. The client forms a request, which includes the client serial number, encrypts the request with the server public key, and sends the download request to the server. The server decrypts the request with the server's private key and authenticates the client. The received client serial number is used to search for a client public key that corresponds to the embedded client private key. The server encrypts its response, which includes the requested information, with the client public key of the requesting client, and only the private key in the requesting client can be used to decrypt the information downloaded from the server.
    Type: Grant
    Filed: April 12, 2001
    Date of Patent: October 13, 2009
    Assignee: International Business Machines Corporation
    Inventors: David John Craft, Pradeep K. Dubey, Harm Peter Hofstee, James Allan Kahle
  • Patent number: 7561489
    Abstract: A system and method of selective row energization based on write data, with a selective row energization system including a storage array 102 having M rows 104 and N columns 106; an N-bit data word register 108; a uniform-detect circuit 110 responsive to a data word to generate a uniform word data bit having a first value when the data word is uniform; an M-bit uniform-detect register 112 having M uniform-detect latches 114, each being associated with one of the M rows 104 and storing the uniform word data bit for the data word stored in the associated M row 104; and an M-bit row driver device 116 responsive to the uniform word data bit for each of the M rows 104 to inhibit energization of the M rows 104 for which the uniform word data bit is the first value.
    Type: Grant
    Filed: May 22, 2008
    Date of Patent: July 14, 2009
    Assignee: International Business Machines Corporation
    Inventors: Michael J. Lee, Jose A. Paredes, Peter J. Klim, Sam G. Chu
  • Patent number: 7549137
    Abstract: A novel iterative latch placement scheme wherein the latches are gradually pulled by increasing attraction force until they are eventually placed next to a clock distribution structure such as a local clock buffer (LCB). During the iterations, timing optimizations such as gate sizing and re-buffering are invoked in order to keep the timing estimation accurate. By applying the iterative clock net weighting adjustment, the present invention allows tighter interaction between logic placement and clock placement which leads to higher quality timing and significant power savings.
    Type: Grant
    Filed: December 14, 2006
    Date of Patent: June 16, 2009
    Assignee: International Business Machines Corporation
    Inventors: Charles J. Alpert, Shyam Ramji, Chin Ngai Sze, Paul G. Villarrubia
  • Patent number: 7546519
    Abstract: An error detection circuit for a latch precharges two dynamic nodes whose discharge paths are gated by true and complement storage nodes of the latch, such that one and only one of the dynamic nodes always discharges when the clock signal transitions from an active state to an inactive state. If a soft error flips the contents of the latch during storage mode the other dynamic node will discharge. A gate having inputs coupled to the dynamic nodes produces an error signal when both nodes have discharged. The error signal can then be used to select between true and complement outputs of the latch. The invention can be implemented in a more robust embodiment which examines the outputs of two error detection circuits to generate a combined error signal that ensures against false error detection when an upset occurs within one of the detection circuits.
    Type: Grant
    Filed: November 16, 2006
    Date of Patent: June 9, 2009
    Assignee: International Business Machines Corporation
    Inventor: Kanak B. Agarwal
  • Patent number: 7546561
    Abstract: A system and method for determining scan chain correspondence including defining a reference scan chain having reference latches and a reference constraint, each of the reference latches having a reference latch logic cone, the reference constraint having a reference constraint logic cone and being associated with one of the reference latches; defining an implementation scan chain having implementation latches and an implementation constraint, each of the implementation latches having an implementation latch logic cone, the implementation constraint having an implementation constraint logic cone and being associated with one of the implementation latches; matching known corresponding scan points between the reference scan chain and the implementation scan chain; and determining scan chain functional correspondence between the reference latches and the implementation latches from the reference latch logic cones with any associated reference constraint logic cone and the implementation latch logic cones with an
    Type: Grant
    Filed: May 25, 2006
    Date of Patent: June 9, 2009
    Assignee: International Business Machines Corporation
    Inventors: Travis W. Pouarz, Viresh Paruthi
  • Patent number: 7533321
    Abstract: A method of handling a stuck bit in a directory of a cache memory, by defining multiple binary encodings to indicate a defective cache state, detecting an error in a tag stored in a member of the directory (wherein the tag at least includes an address field, a state field and an error-correction field), determining that the error is associated with a stuck bit of the directory member, and writing new state information to the directory member which is selected from one of the binary encodings based on a field location of the stuck bit within the directory member. The multiple binary encodings may include a first binary encoding when the stuck bit is in the address field, a second binary encoding when the stuck bit is in the state field, and a third binary encoding when the stuck bit is in the error-correction field. The new state information may also further be selected based on the value of the stuck bit, e.g.
    Type: Grant
    Filed: September 13, 2005
    Date of Patent: May 12, 2009
    Assignee: International Business Machines Corporation
    Inventors: Robert H. Bell, Jr., Guy L. Guthrie, William J. Starke
  • Patent number: 7512887
    Abstract: A method of creating multiple, alternative presentations within a single electronic presentation, by assigning one or more presentation constraint parameters to the electronic slides, and generating a sequence for presenting less than all of the electronic slides based on the presentation constraint parameters. Different sequences can be generated using different presentation constraint parameters that are assigned to the electronic slides. For example, a first electronic slide could be included in a first sequence, and a second electronic slide (or multiple slides) can be substituted for the first electronic slide in a second sequence. A sequence can be generated by adjusting a scalable constraint associated with the presentation constraint parameters to determine which electronic slides to include. The presentation constraint parameters can include a time factor and a content level.
    Type: Grant
    Filed: July 22, 2004
    Date of Patent: March 31, 2009
    Assignee: International Business Machines Corporation
    Inventors: Susann Marie Keohane, Gerald Francis McBrearty, Shawn Patrick Mullen, Jessica Kelley Murillo, Johnny Meng-Han Shieh
  • Patent number: 7509605
    Abstract: An incremental verification method includes eliminating verification constraints from a first netlist and using the resulting netlist to create a constraint-free composite netlist suitable for determining equivalence between the first netlist and a second netlist of a design. Eliminating a constraint from a netlist may include adding a modified constraint net where the modified constraint net is FALSE for all cycles after any cycle in which the original constraint is FALSE. The method may include, instead of eliminating constraints, determining that the verification result is a target-not-asserted result and that the second netlist constraints are a superset of the first netlist constraints or that the verification result is a target-asserted result and that the first netlist constraints are a superset of the second netlist constraints. In either case, the method may include creating the composite netlist by importing all of the original constraints into the composite netlist.
    Type: Grant
    Filed: December 12, 2005
    Date of Patent: March 24, 2009
    Assignee: International Business Machines Corporation
    Inventors: Jason Raymond Baumgartner, Robert Lowell Kanzelman, Hari Mony, Viresh Paruthi
  • Patent number: 7487397
    Abstract: A method of correcting defects in a storage array of a microprocessor, such as a cache memory, by operating the microprocessor to carry out a functional test procedure which utilizes cache memory, collecting fault data in a trace array during the functional test procedure, identifying a location of the defect in the cache memory using the fault data, and repairing the defect by setting a fuse to reroute access requests for the location to a redundant array. The fault data may include an error syndrome and a failing address. The functional test procedure creates random cache access sequences that cause varying loads of traffic in the cache memory using a test pattern based on a random seed. The functional test procedure may be carried out after completion of a nonfunctional, built-in self test of the microprocessor which sets some of the fuses.
    Type: Grant
    Filed: October 27, 2005
    Date of Patent: February 3, 2009
    Assignee: International Business Machines Corporation
    Inventors: Walter R. Lockwood, Ryan J. Pennington, Hugh Shen, Kenneth L. Wright
  • Patent number: 7484242
    Abstract: Enabling automated provisioning on a data processing network includes providing the network with access to an automated provisioning controller. The controller enables a user to specify resource allocation priorities and uses the user-specified priorities, in conjunction with a resource stabilization policy, to resolve conflicting resource requests. The resource allocation priorities include priorities for demand-based resource requests and maintenance-based resource requests. The stabilization policy includes a policy for constraining allocation of a resource based on forecasted demand and a policy for constraining allocation of a resource based on a scheduled maintenance task.
    Type: Grant
    Filed: September 16, 2004
    Date of Patent: January 27, 2009
    Assignee: International Business Machines Corporation
    Inventors: Vijay Kumar Aggarwal, David Werner Bachmann, Uzi Hardoon, Craig M. Lawton, Raymond P. Pekowski, Christopher Andrew Peters, Puthukode G. Ramachandran, Lorin Evan Ullmann, John Patrick Whitfield
  • Patent number: 7484091
    Abstract: A method is presented for implementing a trusted computing environment within a data processing system. A hypervisor is initialized within the data processing system, and the hypervisor supervises a plurality of logical, partitionable, runtime environments within the data processing system. The hypervisor reserves a logical partition for a hypervisor-based trusted platform module (TPM) and presents the hypervisor-based trusted platform module to other logical partitions as a virtual device via a device interface. Each time that the hypervisor creates a logical partition within the data processing system, the hypervisor also instantiates a logical TPM within the reserved partition such that the logical TPM is anchored to the hypervisor-based TPM. The hypervisor manages multiple logical TPM's within the reserved partition such that each logical TPM is uniquely associated with a logical partition.
    Type: Grant
    Filed: April 29, 2004
    Date of Patent: January 27, 2009
    Assignee: International Business Machines Corporation
    Inventors: Steven A. Bade, Ryan Charles Catherman, James Patrick Hoff, Nia Letise Kelley, Emily Jane Ratliff
  • Patent number: 7484199
    Abstract: Wirelength in a net of an integrated circuit design is reduced by forming clusters of sinks to be interconnected, inserting a buffer at each cluster, and providing branch connections between clusters by connecting a sink of one cluster to a buffer of another cluster, to create a buffer tree spanning all sinks. The buffers are inserted at a point on a respective bounding box of a cluster that is closest to a source for the net. A sink that provides a branch connection to the buffer of another cluster is the closest sink to that buffer (except for those sinks in the cluster). Clusters may be formed by examining different pairs of the sinks with different bounding boxes, and identifying one of the pairs whose bounding box has a lowest half-perimeter as the best pair for clustering.
    Type: Grant
    Filed: May 16, 2006
    Date of Patent: January 27, 2009
    Assignee: International Business Machines Corporation
    Inventors: Charles J. Alpert, Tuhin Mahmud, Stephen T. Quay
  • Patent number: 7480804
    Abstract: An architecture for a distributed data processing system comprises a system-level service processor along with one or more node-level service processors; each are uniquely associated with a node, and each is extended to comprise any components that are necessary for operating the nodes as trusted platforms, such as a TPM and a CRTM in accordance with the security model of the Trusted Computing Group. These node-level service processors then inter-operate with the system-level service processor, which also contains any components that are necessary for operating the system as a whole as a trusted platform. A TPM within the system-level service processor aggregates integrity metrics that are gathered by the node-level service processors, thereafter reporting integrity metrics as requested, e.g., to a hypervisor, thereby allowing a large distributed data processing system to be validated as a trusted computing environment while allowing its highly parallelized initialization process to proceed.
    Type: Grant
    Filed: April 29, 2004
    Date of Patent: January 20, 2009
    Assignee: International Business Machines Corporation
    Inventors: Steven A. Bade, Ryan Charles Catherman, James Patrick Hoff, William Lee Terrell
  • Patent number: 7461110
    Abstract: A more efficient method of counting the number of zeros in a 4-bit value generates three output bits (q0, q1 and q2) from four input bits (a0, a1, a2 and a3) according to the logic equations q0=not(a1+a2+a3+a4), q1=not(a0+a1), q2=a1(not a0)+not(a0+a2). These output bits yield the number of non-significant (leading or trailing) zeros in the 4-bit value. The invention may be implemented in a 16-bit zero counter having four 4-bit decoders, but is applicable to any number of zero counters. The output bits from the four 4-bit decoders can be combined to yield a 5-bit count whose most significant bit is a one when all input bits from all four of the 4-bit blocks are zero. A multiplexer stage derives two outputs based on a portion of the decode bits. For wider counters, the output stage uses four AOI21 gates to merge additional decode bits from a next lower 16-bit zero counter.
    Type: Grant
    Filed: May 17, 2005
    Date of Patent: December 2, 2008
    Assignee: International Business Machines Corporation
    Inventors: Aleksandr Kaplun, Huajun J. Wen
  • Patent number: 7453759
    Abstract: Asynchronous behavior of a circuit is modeled by modifying latches in a netlist to add an extra port to the latches, e.g., a single-port latch is transformed into a dual-port latch. Each input port has an enable line and a data input. The data input in the added port is a feedback line from the latch output, and the enable line in the added port is the logical NOR of all of the original enable lines. By adding this extra latch port in the higher-level model, it becomes possible to introduce assertion logic to ensure that one and only one latch port for a given latch is ever active during the same simulation cycle. The model can then be tested earlier in the design methodology prior to the availability of the post-synthesis netlist. The model can also be used in both simulation and formal or semi-formal verification.
    Type: Grant
    Filed: April 26, 2006
    Date of Patent: November 18, 2008
    Assignee: International Business Machines Corporation
    Inventors: Yee Ja, Bradley S. Nelson, Wolfgang Roesner
  • Patent number: 7447620
    Abstract: Asynchronous behavior of a circuit is emulated by modifying a netlist to insert additional logic at a driving element such as a latch. The additional logic outputs one of (i) a present output from the driving element, (ii) a delayed output from the driving element, or (iii) a random value, which drives downstream logic. The output of the additional logic is selectively responsive to a user-controlled skew enable input. The invention allows for simpler data skew logic transformations which are applicable to both latches and primary inputs, with no dependencies on any clock net.
    Type: Grant
    Filed: February 23, 2006
    Date of Patent: November 4, 2008
    Assignee: International Business Machines Corporation
    Inventors: Zoltan T. Hidvegi, Yee Ja, Bradley S. Nelson
  • Patent number: 7448007
    Abstract: A buffer insertion technique addresses slew constraints while minimizing buffer cost. The method builds initial solutions for the sinks, each having an associated cost, slew and capacitance. As a solution propagates toward a source, wire capacitance and wire slew are added to the solution. When a buffer is selected for possible insertion, the slew of the solution is set to zero while the cost of the solution is incremented based on the selected buffer and the capacitance is set to an intrinsic capacitance of the buffer. The solutions of two intersecting wire branches are merged by adding branch capacitances and costs, and selecting the highest branch slew. The solution sets are updated by disregarding solutions which have a slew component greater than a slew constraint, and any solution that is dominated by another solution is eliminated. The solution having the smallest cost is selected as the final solution.
    Type: Grant
    Filed: July 14, 2006
    Date of Patent: November 4, 2008
    Assignee: International Business Machines Corporation
    Inventors: Charles J. Alpert, Arvind K. Karandikar, Tuhin Mahmud, Stephen T. Quay, Chin Ngai Sze
  • Patent number: 7448015
    Abstract: A net of an integrated circuit design is analyzed by unfolding paths on the receive side of an asynchronous boundary to facilitate modeling of the propagation of a metastable value from a receive latch to sinks of the net. The paths are unfolded by replicating combinational logic and wiring along the coincident portions to form non-intersecting, separate paths from the receive latch to two or more sinks. Common data or control inputs are provided for the gates in the replicated combinational logic. Driver logic may additionally be inserted along each replicated path, upstream of the combinational logic, to independently drive each of the sinks.
    Type: Grant
    Filed: May 19, 2006
    Date of Patent: November 4, 2008
    Assignee: International Business Machines Corporation
    Inventors: Yee Ja, Bradley S. Nelson