Patents by Inventor Nirmal R. Saxena

Nirmal R. Saxena has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 11720472
    Abstract: Memory, used by a computer to store data, is generally prone to faults, including permanent faults (i.e. relating to a lifetime of the memory hardware), and also transient faults (i.e. relating to some external cause) which are otherwise known as soft errors. Since soft errors can change the state of the data in the memory and thus cause errors in applications reading and processing the data, there is a desire to characterize the degree of vulnerability of the memory to soft errors. In particular, once the vulnerability for a particular memory to soft errors has been characterized, cost/reliability trade-offs can be determined, or soft error detection mechanisms (e.g. parity) may be selectively employed for the memory. In some cases, memory faults can be diagnosed by redundant execution and a diagnostic coverage may be determined.
    Type: Grant
    Filed: November 9, 2021
    Date of Patent: August 8, 2023
    Assignee: NVIDIA Corporation
    Inventors: Richard Gavin Bramley, Philip Payman Shirvani, Nirmal R. Saxena
  • Publication number: 20230089736
    Abstract: A memory device and a system that implements a single symbol correction, double symbol detection (SSC-DSD+) error correction scheme are provided. The scheme is implemented by calculating four syndrome symbols in accordance with a Reed-Solomon (RS) codeword; determining three location bytes in accordance with three corresponding pairs of syndrome symbols in the four syndrome symbols; and generating an output based on a comparison of the three location bytes. The output may include: corrected data responsive to determining that the three location bytes match; an indication of a detected-and-corrected error (DCE) responsive to determining that two of the three location bytes match; or an indication of a detected-yet-uncorrected error (DUE) responsive to determining that none of the three location bytes match. A variant of the SSC-DSD+ decoder may be implemented using a carry-free subtraction operation to perform sanity checking.
    Type: Application
    Filed: September 21, 2022
    Publication date: March 23, 2023
    Inventors: Michael Brendan Sullivan, Nirmal R. Saxena, Stephen William Keckler
  • Patent number: 11494265
    Abstract: In general, data is susceptible to errors caused by faults in hardware (i.e. permanent faults), such as faults in the functioning of memory and/or communication channels. To detect errors in data caused by hardware faults, the error correcting code (ECC) was introduced, which essentially provides a sort of redundancy to the data that can be used to validate that the data is free from errors caused by hardware faults. In some cases, the ECC can also be used to correct errors in the data caused by hardware faults. However, the ECC itself is also susceptible to errors, including specifically errors caused by faults in the ECC logic. A method, computer readable medium, and system are thus provided for securing against errors in an ECC.
    Type: Grant
    Filed: December 31, 2020
    Date of Patent: November 8, 2022
    Assignee: NVIDIA Corporation
    Inventor: Nirmal R. Saxena
  • Publication number: 20220114075
    Abstract: Memory, used by a computer to store data, is generally prone to faults, including permanent faults (i.e. relating to a lifetime of the memory hardware), and also transient faults (i.e. relating to some external cause) which are otherwise known as soft errors. Since soft errors can change the state of the data in the memory and thus cause errors in applications reading and processing the data, there is a desire to characterize the degree of vulnerability of the memory to soft errors. In particular, once the vulnerability for a particular memory to soft errors has been characterized, cost/reliability trade-offs can be determined, or soft error detection mechanisms (e.g. parity) may be selectively employed for the memory. In some cases, memory faults can be diagnosed by redundant execution and a diagnostic coverage may be determined.
    Type: Application
    Filed: November 9, 2021
    Publication date: April 14, 2022
    Inventors: Richard Gavin Bramley, Philip Payman Shirvani, Nirmal R. Saxena
  • Patent number: 11188442
    Abstract: Memory, used by a computer to store data, is generally prone to faults, including permanent faults (i.e. relating to a lifetime of the memory hardware), and also transient faults (i.e. relating to some external cause) which are otherwise known as soft errors. Since soft errors can change the state of the data in the memory and thus cause errors in applications reading and processing the data, there is a desire to characterize the degree of vulnerability of the memory to soft errors. In particular, once the vulnerability for a particular memory to soft errors has been characterized, cost/reliability trade-offs can be determined, or soft error detection mechanisms (e.g. parity) may be selectively employed for the memory. In some cases, memory faults can be diagnosed by redundant execution and a diagnostic coverage may be determined.
    Type: Grant
    Filed: April 15, 2020
    Date of Patent: November 30, 2021
    Assignee: NVIDIA Corporation
    Inventors: Richard Gavin Bramley, Philip Payman Shirvani, Nirmal R. Saxena
  • Publication number: 20210124644
    Abstract: In general, data is susceptible to errors caused by faults in hardware (i.e. permanent faults), such as faults in the functioning of memory and/or communication channels. To detect errors in data caused by hardware faults, the error correcting code (ECC) was introduced, which essentially provides a sort of redundancy to the data that can be used to validate that the data is free from errors caused by hardware faults. In some cases, the ECC can also be used to correct errors in the data caused by hardware faults. However, the ECC itself is also susceptible to errors, including specifically errors caused by faults in the ECC logic. A method, computer readable medium, and system are thus provided for securing against errors in an ECC.
    Type: Application
    Filed: December 31, 2020
    Publication date: April 29, 2021
    Inventor: Nirmal R. Saxena
  • Patent number: 10908995
    Abstract: In general, data is susceptible to errors caused by faults in hardware (i.e. permanent faults), such as faults in the functioning of memory and/or communication channels. To detect errors in data caused by hardware faults, the error correcting code (ECC) was introduced, which essentially provides a sort of redundancy to the data that can be used to validate that the data is free from errors caused by hardware faults. In some cases, the ECC can also be used to correct errors in the data caused by hardware faults. However, the ECC itself is also susceptible to errors, including specifically errors caused by faults in the ECC logic. A method, computer readable medium, and system are thus provided for securing against errors in an ECC.
    Type: Grant
    Filed: September 20, 2018
    Date of Patent: February 2, 2021
    Assignee: NVIDIA Corporation
    Inventor: Nirmal R. Saxena
  • Publication number: 20200293425
    Abstract: Memory, used by a computer to store data, is generally prone to faults, including permanent faults (i.e. relating to a lifetime of the memory hardware), and also transient faults (i.e. relating to some external cause) which are otherwise known as soft errors. Since soft errors can change the state of the data in the memory and thus cause errors in applications reading and processing the data, there is a desire to characterize the degree of vulnerability of the memory to soft errors. In particular, once the vulnerability for a particular memory to soft errors has been characterized, cost/reliability trade-offs can be determined, or soft error detection mechanisms (e.g. parity) may be selectively employed for the memory. In some cases, memory faults can be diagnosed by redundant execution and a diagnostic coverage may be determined.
    Type: Application
    Filed: April 15, 2020
    Publication date: September 17, 2020
    Inventors: Richard Gavin Bramley, Philip Payman Shirvani, Nirmal R. Saxena
  • Patent number: 10691572
    Abstract: Memory, used by a computer to store data, is generally prone to faults, including permanent faults (i.e. relating to a lifetime of the memory hardware), and also transient faults (i.e. relating to some external cause) which are otherwise known as soft errors. Since soft errors can change the state of the data in the memory and thus cause errors in applications reading and processing the data, there is a desire to characterize the degree of vulnerability of the memory to soft errors. In particular, once the vulnerability for a particular memory to soft errors has been characterized, cost/reliability trade-offs can be determined, or soft error detection mechanisms (e.g. parity) may be selectively employed for the memory. A method, computer readable medium, and system are provided for using liveness as a factor to evaluate memory vulnerability to soft errors.
    Type: Grant
    Filed: August 28, 2018
    Date of Patent: June 23, 2020
    Assignee: NVIDIA Corporation
    Inventors: Richard Gavin Bramley, Philip Payman Shirvani, Nirmal R. Saxena
  • Publication number: 20190102254
    Abstract: In general, data is susceptible to errors caused by faults in hardware (i.e. permanent faults), such as faults in the functioning of memory and/or communication channels. To detect errors in data caused by hardware faults, the error correcting code (ECC) was introduced, which essentially provides a sort of redundancy to the data that can be used to validate that the data is free from errors caused by hardware faults. In some cases, the ECC can also be used to correct errors in the data caused by hardware faults. However, the ECC itself is also susceptible to errors, including specifically errors caused by faults in the ECC logic. A method, computer readable medium, and system are thus provided for securing against errors in an ECC.
    Type: Application
    Filed: September 20, 2018
    Publication date: April 4, 2019
    Inventor: Nirmal R. Saxena
  • Publication number: 20190065338
    Abstract: Memory, used by a computer to store data, is generally prone to faults, including permanent faults (i.e. relating to a lifetime of the memory hardware), and also transient faults (i.e. relating to some external cause) which are otherwise known as soft errors. Since soft errors can change the state of the data in the memory and thus cause errors in applications reading and processing the data, there is a desire to characterize the degree of vulnerability of the memory to soft errors. In particular, once the vulnerability for a particular memory to soft errors has been characterized, cost/reliability trade-offs can be determined, or soft error detection mechanisms (e.g. parity) may be selectively employed for the memory. A method, computer readable medium, and system are provided for using liveness as a factor to evaluate memory vulnerability to soft errors.
    Type: Application
    Filed: August 28, 2018
    Publication date: February 28, 2019
    Inventors: Richard Gavin Bramley, Philip Payman Shirvani, Nirmal R. Saxena
  • Patent number: 6055629
    Abstract: A method for a prediction correlation between a first group of branch instructions in a bunch of instructions and a second group of branch instructions in a bunch of instructions is disclosed. The method includes indicating a direction of a plurality of branch instructions in a bunch of instructions. More particularly, the method includes building an address composed of an instruction fetch address and bits in a history register. The method accesses a bunch of instructions using the fetch address and accesses a prediction bits set from a branch history table using the composed address. The accessed bunch of instructions are processed. Further, the history register and the branch history table are updated to correlate a first group of a branch instructions in the accessed bunch of instructions to a second group of branch instructions in a next group of branch instructions in the bunch of instructions.
    Type: Grant
    Filed: January 19, 1999
    Date of Patent: April 25, 2000
    Assignee: Fujitsu, Ltd.
    Inventors: Paritosh M. Kulkarni, Richard Reeve, Nirmal R. Saxena
  • Patent number: 5896529
    Abstract: A method for a prediction correlation between a first group of branch instructions in a bunch of instructions and a second group of branch instructions in a bunch of instructions is disclosed. The method includes indicating a direction of a plurality of branch instructions in a bunch of instructions. More particularly, the method includes building an address composed of an instruction fetch address and bits in a history register. The method accesses a bunch of instructions using the fetch address and accesses a prediction bits set from a branch history table using the composed address. The accessed bunch of instructions are processed. Further, the history register and the branch history table are updated to correlate a first group of a branch instructions in the accessed bunch of instructions to a second group of branch instructions in a next group of branch instructions in the bunch of instructions.
    Type: Grant
    Filed: December 24, 1997
    Date of Patent: April 20, 1999
    Assignee: Fujitsu Ltd.
    Inventors: Paritosh M. Kulkarni, Richard Reeve, Nirmal R. Saxena
  • Patent number: 5781562
    Abstract: An apparatus generates patterns useful for testing storage devices using a modified form of a shift register. A control input and two bits are added and the least significant bit of the result is substituted in place of one of the bits which are rotatably shifted to generate subsequent patterns. The patterns generated may be used to test storage devices by writing the pattern to the storage device, reading the device and comparing the pattern read with the pattern written. A difference indicates a storage device error.
    Type: Grant
    Filed: September 30, 1997
    Date of Patent: July 14, 1998
    Assignee: Fujitsu Limited
    Inventor: Nirmal R. Saxena
  • Patent number: 5777590
    Abstract: An LCD controller for use e.g. in a portable computer provides gray scale shading for both monochromatic and color displays using frame rate control modulation for intensity shading for each pixel. The gray scale shading process and circuit do not require any memory for storing phase tiling matrices or frame modulation pattern sequences; both of these instead are generated in real time using a linear matrix logic structure. Use of linear matrix operations also allows generation of various phase shifts of frame modulation pattern sequences to provide a better image on the display. In addition to providing programmable 4, 8, or 16 intensity levels, the present method and apparatus provide that vertically, horizontally or diagonally adjacent pixels on the display never have the same phase in the same frame, and in addition that the pixel display drivers are uniformly loaded.
    Type: Grant
    Filed: August 25, 1995
    Date of Patent: July 7, 1998
    Assignee: S3, Incorporated
    Inventors: Nirmal R. Saxena, Sridhar Manthani
  • Patent number: 5742805
    Abstract: Methods and apparati predict whether conditional branch computer instructions should be taken or not taken. A history register is maintained to record the history of groups of instructions, updated only once for each group. The history register and an address of one of the bytes of one of the instructions in each group are appended or otherwise combined to create an address to a table of two-bit saturating counters. The value of one of the bits of the counter at the address created is used for predicting all the conditional branch instructions for each branch in the group.
    Type: Grant
    Filed: February 15, 1996
    Date of Patent: April 21, 1998
    Assignee: Fujitsu Ltd.
    Inventors: Paritosh M. Kulkarni, Richard Reeve, Nirmal R. Saxena
  • Patent number: 5734664
    Abstract: Methods and apparati allow a more compact error correction code which corrects and detects one or more bit errors and detects a memory chip failure to be used for the detection and correction of errors. Rather than store data in groups of bits equal to the width of the memory chip, data is stored in groups of bits smaller than the width of a chip. An error correction code is used that detects the failure of a chip having the width of the group. Because the group is smaller than the width of the chip, a smaller error code may be used.
    Type: Grant
    Filed: June 23, 1995
    Date of Patent: March 31, 1998
    Assignee: Fujitsu Limited
    Inventor: Nirmal R. Saxena
  • Patent number: 5652580
    Abstract: A method and apparatus detects whether more than one object has been selected from a set of objects. A unique code and an error code is coupled to objects in the set. At least one object is selected and the unique codes from the selected object are logically summed, as are the error codes from the selected objects. A test code is generated from the logically summed unique code and tested for equality with the logically summed error code to determine if more than one object was selected.
    Type: Grant
    Filed: June 9, 1995
    Date of Patent: July 29, 1997
    Assignee: HaL Computer Systems, Inc.
    Inventor: Nirmal R. Saxena