Patents by Inventor Bharat Kumar Rangarajan

Bharat Kumar Rangarajan 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: 11880454
    Abstract: A method to prevent a malicious attack on CPU subsystem (CPUSS) hardware is described. The method includes auto-calibrating tunable delay elements of a dynamic variation monitor (DVM) using an auto-calibration value computed in response to each detected change of a clock frequency (Fclk)/supply voltage (Vdd) of the CPUSS hardware. The method also includes comparing the auto-calibration value with a threshold reference calibration value to determine whether the malicious attack is detected. The method further includes forcing a safe clock frequency (Fclk)/safe supply voltage (Vdd) to the CPUSS hardware when the malicious attack is detected.
    Type: Grant
    Filed: May 14, 2020
    Date of Patent: January 23, 2024
    Assignee: QUALCOMM Incorporated
    Inventors: Bharat Kumar Rangarajan, Dipti Ranjan Pal, Keith Alan Bowman, Srinivas Turaga, Ateesh Deepankar De, Shih-Hsin Jason Hu, Chandan Agarwalla
  • Patent number: 11630694
    Abstract: Task scheduling in a computing device may be based in part on voltage regulator efficiency. For an additional task to be scheduled, multiple task scheduling cases may be determined that represent execution of the additional task on each of a number of processors concurrently with one or more other tasks executing among the processors. For each task scheduling case, a regulator input power level for a voltage regulator may be determined based on a performance level indication associated with the additional task, the one or more other tasks executing on the processors, and the efficiency level of each voltage regulator. For each task scheduling case, a total regulator input power level may be determined by summing the regulator input power levels for all voltage regulators. The additional task may be executed on a processor associated with a task scheduling case for which total regulator input power is lowest.
    Type: Grant
    Filed: January 13, 2021
    Date of Patent: April 18, 2023
    Assignee: QUALCOMM Incorporated
    Inventors: Vijayakumar Ashok Dibbad, Bharat Kumar Rangarajan, Prashanth Kumar Kakkireni, Srinivas Turaga
  • Patent number: 11604505
    Abstract: Various embodiments include methods and devices for system on chip infrastructure of system on chip infrastructure secure memory access and power management. Some embodiments, include determining whether a processor is performing a secure memory access transaction, and gating a clock signal from being transmitted to a secure portion of a memory in response to determining that the processor is not performing a secure memory access transaction. Some embodiments include determining whether any processor is operating in a secure mode, and transmitting a retention signal to the secure portion of the memory in response to determining that no processor is operating in a secure mode. The retention signal may be configured to set a retention state for the secure portion of the memory.
    Type: Grant
    Filed: December 29, 2020
    Date of Patent: March 14, 2023
    Assignee: QUALCOMM Incorporated
    Inventors: Bharat Kumar Rangarajan, Rajesh Arimilli, Rengarajan Ragavan
  • Patent number: 11507174
    Abstract: In certain aspects, a tag memory comprises a plurality of non-configurable tag columns configured to be powered on during a normal operation; and a plurality of configurable tag columns, wherein a first portion of the plurality of configurable tag columns is configured to be powered off during the normal operation and a second portion of the plurality of configurable tag columns is configured to be powered on during the normal operation.
    Type: Grant
    Filed: February 25, 2020
    Date of Patent: November 22, 2022
    Assignee: QUALCOMM Incorporated
    Inventors: Bharat Kumar Rangarajan, Srinivas Turaga
  • Publication number: 20220365580
    Abstract: In controlling power in a portable computing device (“PCD”), a power supply input to a PCD subsystem may be modulated with a modulation signal when an over-current condition is detected. Detection of the modulation signal may indicate to a processing core of the subsystem to reduce its processing load. Compensation for the modulation signal in the power supply input may be applied so that the processing core is essentially unaffected by the modulation signal.
    Type: Application
    Filed: May 17, 2021
    Publication date: November 17, 2022
    Inventors: VIJAYAKUMAR ASHOK DIBBAD, Bharat Kumar RANGARAJAN, Dipti Ranjan PAL, Keith Alan BOWMAN, Matthew SEVERSON, Gordon LEE
  • Patent number: 11493980
    Abstract: In controlling power in a portable computing device (“PCD”), a power supply input to a PCD subsystem may be modulated with a modulation signal when an over-current condition is detected. Detection of the modulation signal may indicate to a processing core of the subsystem to reduce its processing load. Compensation for the modulation signal in the power supply input may be applied so that the processing core is essentially unaffected by the modulation signal.
    Type: Grant
    Filed: May 17, 2021
    Date of Patent: November 8, 2022
    Assignee: QUALCOMM Incorporated
    Inventors: Vijayakumar Ashok Dibbad, Bharat Kumar Rangarajan, Dipti Ranjan Pal, Keith Alan Bowman, Matthew Severson, Gordon Lee
  • Patent number: 11493986
    Abstract: Various embodiments include methods and devices for cache memory power control. Some embodiments may include determining whether a processor is entering a lowest power mode of the processor, and switching a lowest power mode switch control signal to indicate to a cache power switch of the processor switching an electrical connection of a cache memory from a memory power rail to a processor power rail in response to determining that the processor is entering a lowest power mode.
    Type: Grant
    Filed: December 22, 2019
    Date of Patent: November 8, 2022
    Assignee: QUALCOMM Incorporated
    Inventors: Bharat Kumar Rangarajan, Rajesh Arimilli, Srinivas Turaga
  • Publication number: 20220222112
    Abstract: Task scheduling in a computing device may be based in part on voltage regulator efficiency. For an additional task to be scheduled, multiple task scheduling cases may be determined that represent execution of the additional task on each of a number of processors concurrently with one or more other tasks executing among the processors. For each task scheduling case, a regulator input power level for a voltage regulator may be determined based on a performance level indication associated with the additional task, the one or more other tasks executing on the processors, and the efficiency level of each voltage regulator. For each task scheduling case, a total regulator input power level may be determined by summing the regulator input power levels for all voltage regulators. The additional task may be executed on a processor associated with a task scheduling case for which total regulator input power is lowest.
    Type: Application
    Filed: January 13, 2021
    Publication date: July 14, 2022
    Inventors: Vijayakumar Ashok DIBBAD, Bharat Kumar RANGARAJAN, Prashanth Kumar KAKKIRENI, Srinivas TURAGA
  • Publication number: 20220206559
    Abstract: Various embodiments include methods and devices for system on chip infrastructure of system on chip infrastructure secure memory access and power management. Some embodiments, include determining whether a processor is performing a secure memory access transaction, and gating a clock signal from being transmitted to a secure portion of a memory in response to determining that the processor is not performing a secure memory access transaction. Some embodiments include determining whether any processor is operating in a secure mode, and transmitting a retention signal to the secure portion of the memory in response to determining that no processor is operating in a secure mode. The retention signal may be configured to set a retention state for the secure portion of the memory.
    Type: Application
    Filed: December 29, 2020
    Publication date: June 30, 2022
    Inventors: Bharat Kumar RANGARAJAN, Rajesh ARIMILLI, Rengarajan RAGAVAN
  • Publication number: 20210357502
    Abstract: A method to prevent a malicious attack on CPU subsystem (CPUSS) hardware is described. The method includes auto-calibrating tunable delay elements of a dynamic variation monitor (DVM) using an auto-calibration value computed in response to each detected change of a clock frequency (Fclk)/supply voltage (Vdd) of the CPUSS hardware. The method also includes comparing the auto-calibration value with a threshold reference calibration value to determine whether the malicious attack is detected. The method further includes forcing a safe clock frequency (Fclk)/safe supply voltage (Vdd) to the CPUSS hardware when the malicious attack is detected.
    Type: Application
    Filed: May 14, 2020
    Publication date: November 18, 2021
    Inventors: Bharat Kumar RANGARAJAN, Dipti Ranjan PAL, Keith Alan BOWMAN, Srinivas TURAGA, Ateesh Deepankar DE, Shih-Hsin Jason HU, Chandan AGARWALLA
  • Patent number: 11169593
    Abstract: Various aspects are described herein. In some aspects, the disclosure provides selective coupling of portions of a memory structure to voltage supplies. Certain aspects provide a computing device. The computing device includes a memory comprising a plurality of portions that are individually power collapsible. The computing device further includes a first voltage rail supplying a first voltage. The computing device further includes a second voltage rail supplying a second voltage. The computing device further includes a plurality of switching circuits, each switching circuit configured to selectively couple a corresponding one of the plurality of portions with the first voltage rail or the second voltage rail. The computing device further includes a controller configured to control each of the plurality of switching circuits based on a current active mode of the memory, and a current operating mode of each of the plurality of portions.
    Type: Grant
    Filed: May 19, 2020
    Date of Patent: November 9, 2021
    Assignee: QUALCOMM Incorporated
    Inventors: Raghavendra Srinivas, Bharat Kumar Rangarajan, Rajesh Arimilli
  • Publication number: 20210263581
    Abstract: In certain aspects, a tag memory comprises a plurality of non-configurable tag columns configured to be powered on during a normal operation; and a plurality of configurable tag columns, wherein a first portion of the plurality of configurable tag columns is configured to be powered off during the normal operation and a second portion of the plurality of configurable tag columns is configured to be powered on during the normal operation.
    Type: Application
    Filed: February 25, 2020
    Publication date: August 26, 2021
    Inventors: Bharat Kumar RANGARAJAN, Srinivas TURAGA
  • Publication number: 20210191500
    Abstract: Various embodiments include methods and devices for cache memory power control. Some embodiments may include determining whether a processor is entering a lowest power mode of the processor, and switching a lowest power mode switch control signal to indicate to a cache power switch of the processor switching an electrical connection of a cache memory from a memory power rail to a processor power rail in response to determining that the processor is entering a lowest power mode.
    Type: Application
    Filed: December 22, 2019
    Publication date: June 24, 2021
    Inventors: Bharat Kumar RANGARAJAN, Rajesh ARIMILLI, Srinivas TURAGA
  • Publication number: 20210157382
    Abstract: A CPU core may be woken up from a power-saving mode in a portable computing device in a manner that depends upon whether the wake-up event source is a snoop request or an interrupt. A core power controller may monitor for and detect snoop requests and interrupts directed to the CPU core while the CPU core is in the power-saving mode. In response to detecting a snoop request, the core power controller may wake up snoop-related components of the CPU core while refraining from waking up non-snoop-related components of the CPU core. In response to detecting an interrupt, the core power controller may wake up both the snoop-related components and the non-snoop-related components of the CPU core.
    Type: Application
    Filed: November 27, 2019
    Publication date: May 27, 2021
    Inventors: Bharat Kumar Rangarajan, Rajesh Arimilli
  • Patent number: 10831667
    Abstract: Various aspects are described herein. In some aspects, the disclosure provides techniques for accessing tag information in a memory line. The techniques include determining an operation to perform on at least one memory line of a memory. The techniques further include performing the operation by accessing only a portion of the at least one memory line, wherein the only the portion of the at least one memory line comprises one or more flag bits that are independently accessible from remaining bits of the at least one memory line.
    Type: Grant
    Filed: October 29, 2018
    Date of Patent: November 10, 2020
    Assignee: Qualcomm Incorporated
    Inventors: Bharat Kumar Rangarajan, Chulmin Jung, Rakesh Misra
  • Publication number: 20200278739
    Abstract: Various aspects are described herein. In some aspects, the disclosure provides selective coupling of portions of a memory structure to voltage supplies. Certain aspects provide a computing device. The computing device includes a memory comprising a plurality of portions that are individually power collapsible. The computing device further includes a first voltage rail supplying a first voltage. The computing device further includes a second voltage rail supplying a second voltage. The computing device further includes a plurality of switching circuits, each switching circuit configured to selectively couple a corresponding one of the plurality of portions with the first voltage rail or the second voltage rail. The computing device further includes a controller configured to control each of the plurality of switching circuits based on a current active mode of the memory, and a current operating mode of each of the plurality of portions.
    Type: Application
    Filed: May 19, 2020
    Publication date: September 3, 2020
    Inventors: Raghavendra SRINIVAS, Bharat Kumar RANGARAJAN, Rajesh ARIMILLI
  • Patent number: 10691195
    Abstract: Various aspects are described herein. In some aspects, the disclosure provides selective coupling of portions of a memory structure to voltage supplies. Certain aspects provide a computing device. The computing device includes a memory comprising a plurality of portions that are individually power collapsible. The computing device further includes a first voltage rail supplying a first voltage. The computing device further includes a second voltage rail supplying a second voltage. The computing device further includes a plurality of switching circuits, each switching circuit configured to selectively couple a corresponding one of the plurality of portions with the first voltage rail or the second voltage rail. The computing device further includes a controller configured to control each of the plurality of switching circuits based on a current active mode of the memory, and a current operating mode of each of the plurality of portions.
    Type: Grant
    Filed: February 28, 2018
    Date of Patent: June 23, 2020
    Assignee: QUALCOMM Incorporated
    Inventors: Raghavendra Srinivas, Bharat Kumar Rangarajan, Rajesh Arimilli
  • Patent number: 10664006
    Abstract: Method and Apparatus for automatically switching to a low power retention mode based on architectural clock gating is disclosed. In some implementations, a system includes a central processing unit (CPU), comprising a clock gating cell configured to receive a clock enable signal. The system further includes a switching module configured to monitor the clock enable signal and to cause a power manager to switch the CPU from a first power supply output to a second power supply output in response to the clock enable signal changing from a first state to a second state.
    Type: Grant
    Filed: January 11, 2018
    Date of Patent: May 26, 2020
    Assignee: QUALCOMM Incorporated
    Inventors: Bharat Kumar Rangarajan, Rakesh Misra, Rajesh Arimilli
  • Publication number: 20200133862
    Abstract: Various aspects are described herein. In some aspects, the disclosure provides techniques for accessing tag information in a memory line. The techniques include determining an operation to perform on at least one memory line of a memory. The techniques further include performing the operation by accessing only a portion of the at least one memory line, wherein the only the portion of the at least one memory line comprises one or more flag bits that are independently accessible from remaining bits of the at least one memory line.
    Type: Application
    Filed: October 29, 2018
    Publication date: April 30, 2020
    Inventors: Bharat Kumar RANGARAJAN, Chulmin JUNG, Rakesh MISRA
  • Patent number: 10466766
    Abstract: Systems, methods, and apparatus for operating a central processing unit (CPU) are provided. The CPU includes a plurality of memories including a first group of memories and a second group of memories. The plurality of memories are grouped based on a timing criticality of each memory. The CPU further includes a memory core (MX) voltage supply configured to provide the plurality of memories with an MX voltage, an application processor core (APC) voltage supply configured to provide the plurality of memories with an APC voltage, and a voltage switching circuit. The voltage switching circuit detects an operating mode of the CPU and switches a voltage provided to at least one of the first group of memories or the second group of memories between the MX voltage and the APC voltage based on a type of the operating mode detected.
    Type: Grant
    Filed: November 9, 2017
    Date of Patent: November 5, 2019
    Assignee: Qualcomm Incorporated
    Inventors: Rajesh Arimilli, Bharat Kumar Rangarajan, Rakesh Misra