According to an example aspect of the present invention, there is provided an apparatus comprising a first processing core configured to generate first control signals and to control a display by providing the first control signals to the display via a first display interface, a second processing core configured to generate second control signals and to control the display by providing the second control signals to the display via a second display interface, and the first processing core being further configured to cause the second processing core to enter and leave a hibernation state based at least partly on a determination, by the first processing core, concerning an instruction from outside the apparatus.

Examples described herein provide for a first core to map a measurement of packet processing activity and operating parameters so that a second core can access the measurement of packet processing activity and potentially modify an operating parameter of the first core. The second core can modify operating parameters of the first core based on the measurement of packet processing activity. The first and second cores can be provisioned on start-up with a common key. The first and second cores can use the common key to encrypt or decrypt measurement of packet processing activity and operating parameters that are shared between the first and second cores. Accordingly, operating parameters of the first core can be modified by a different core while providing for secure modification of operating parameters.

Examples described herein provide for a first core to map a measurement of packet processing activity and operating parameters so that a second core can access the measurement of packet processing activity and potentially modify an operating parameter of the first core. The second core can modify operating parameters of the first core based on the measurement of packet processing activity. The first and second cores can be provisioned on start-up with a common key. The first and second cores can use the common key to encrypt or decrypt measurement of packet processing activity and operating parameters that are shared between the first and second cores. Accordingly, operating parameters of the first core can be modified by a different core while providing for secure modification of operating parameters.

A performance management scheme for a processor based on leakage current measurement in field. The scheme performs the operations of detection and correction. The operation of detection measures per core leakage current in the field (e.g., using voltage regulator electrical current counters). The operation of correction changes the processor power management behavior. For example, processor cores showing high leakage degradation may be logically swapped with cores showing low leakage degradation.

A system includes a power profile engine, a power measurement engine, and a power throttling signal generator. The power profile engine receives a desired power profile, e.g., a first profile current average associated with a first time duration and a second profile current average associated with a second time duration. The power measurement engine measures current being drawn and generates a first running average for the measured currents for the first time duration and generates a second running average for the measured currents for the second time duration. The power throttling signal generator generates a first power throttling signal to throttle power in response to the first running average for the measured currents being greater than the first profile current average and generates a second power throttling signal to throttle power in response to the second running average for the measured currents being greater than the second profile current average.

A clock circuit constructed in a processor integrated circuit includes a phase lock loop PLL, a clock tree, and a clock grid. The clock tree includes a plurality of clock buffers in a layered structure, The clock tree is configured to receive a first clock signal clk_1 that is output by the phase lock loop PLL, and to output a second clock signal clk_2. A plurality of child node circuits (400) are disposed on some nodes of the clock grid, and are configured to generate a third clock signal clk_3 based on the second clock signal clk_2. The clock grid (330) and the clock tree (320) are distributed on multiple dies in a three-dimensional structure of the processor integrated circuit.

Systems and methods are disclosed for processor power management using instruction throttling. For example, an integrated circuit may include a processor core including a processor pipeline configured to execute instructions; a register configured to store a power dial value that indicates a portion of available clock cycles for throttling of instruction flow through the processor pipeline; and an instruction throttling circuit configured to periodically stall removal of instructions from a queue in the processor pipeline for a number of clock cycles that is determined based on the power dial value.

A network device can place some or all of the packet processing pipeline into a low-power state for detected idle intervals of sufficient duration. The network device detects idleness greater than a critical duration and automatically engages a low-power mode involving clock throttling and/or clock gating. The power savings in the packet processing pipeline in the network device is based on the average long-term residency in idleness. The idle power is reduced for the packet processing pipeline in the network device by detecting average long-term idleness as a function of the minimum latency of the packet processing pipeline, which is used to reduce the clock rate of the packet processing pipeline, thereby resulting in power savings for the network device.

A network device can place some or all of the packet processing pipeline into a low-power state for detected idle intervals of sufficient duration. The network device detects idleness greater than a critical duration and automatically engages a low-power mode involving clock throttling and/or clock gating. The power savings in the packet processing pipeline in the network device is based on the average long-term residency in idleness. The idle power is reduced for the packet processing pipeline in the network device by detecting average long-term idleness as a function of the minimum latency of the packet processing pipeline, which is used to reduce the clock rate of the packet processing pipeline, thereby resulting in power savings for the network device.

An apparatus can include processor cores and control circuitry coupled to the processor cores. The control circuitry can detect at least one of a power characteristic and a frequency characteristic of at least one of the processor cores. The control circuitry can determine that a frequency control opportunity is present on at least one of the processor cores based on at least one of the power characteristic and the frequency characteristic. The control circuitry can adjust a power parameter of at least one of the processor cores responsive to determining that the frequency control opportunity is present.