Abstract: An apparatus including a JTAG interface, synchronous bus optimizer, core clocks generator, synchronous strobe driver, and a DLL. The JTAG interface receives control information indicating a first amount to advance a synchronous data strobe associated with a first data group and a second amount to delay a data bit signal associated with a second data group. The synchronous bus optimizer receives the control information, and develops a first value on a first ratio bus that indicates the first amount and a second value on a second ratio bus that indicates the second amount. The core clocks generator advances a data strobe clock by the first amount. The synchronous strobe driver employs the data strobe clock to generate the synchronous data strobe, where the synchronous data strobe, when enabled, is advanced also by the first amount. The DLL generates a delayed data bit signal, delayed by the second amount.

Abstract: An apparatus is provided that compensates for misalignment on a synchronous data bus. The apparatus includes a resistor network, a core clocks generator, and a synchronous strobe driver. The resistor network is configured to provide a ratio signal that indicates an amount to advance a synchronous data strobe associated with a data group. The core clocks generator is coupled to the ratio signal, and is configured to advance a data strobe clock by the amount. The synchronous strobe driver is configured to receive the data strobe clock, and is configured to employ the data strobe clock to generate the synchronous data strobe, where the synchronous data strobe, when enabled, is advanced also by the amount.

Abstract: An apparatus that compensates for misalignment on a synchronous data bus. The apparatus includes a resistor network and a synchronous receiver disposed within a receiving device. The resistor network is configured to provide a ratio signal that indicates an amount to delay a data bit signal associated with a data group, where the data bit signal is transmitted by a transmitting device along with a data strobe signal. The synchronous receiver receives the data bit and the data strobe signals, and includes a delay-locked loop (DLL). The DLL is coupled to the ratio signal, and is configured generate a delayed data bit signal, where the DLL adds the amount of delay to the data bit signal to generate the delayed data bit signal, and where the delayed bit signal is delayed relative to the data strobe signal by the amount, thus allowing for proper reception of the data bit signal.

Abstract: A multi-core processor includes microcode distributed in each core enabling each core to participate in a de-centralized inter-core state discovery process. In a related microcode-implemented method, states of a multi-core processor are discovered by at least two cores participating in a de-centralized inter-core state discovery process. The inter-core state discovery process is carried out through a combination of microcode executing on each participating core and signals exchanged between the cores through sideband non-system-bus communication wires. The discovery process is unmediated by any centralized non-core logic. Applicable discoverable states include target and composite power states, whether and how many cores are enabled, the availability and distribution of various resources, and hierarchical structures and coordination systems for the cores.

Abstract: A method for debugging a multi-core microprocessor includes causing the microprocessor to perform an actual execution of instructions and obtaining from the microprocessor heartbeat information that specifies an actual execution sequence of the instructions by the plurality of cores relative to one another, commanding a corresponding plurality of instances of a software functional model of the cores to execute the instructions according to the actual execution sequence specified by the heartbeat information to generate simulated results of the execution of the instructions, and comparing the simulated results with actual results of the execution of the instructions to determine whether they match. Each core outputs an instruction execution indicator indicating the number of instructions executed by the core each core clock. A heartbeat generator generates a heartbeat indicator for each core on an external bus that indicates the number of instructions executed by each core during each external bus clock cycle.

Abstract: A multi-core processor includes microcode distributed in each core enabling each core to participate in a de-centralized inter-core state discovery process. In a related microcode-implemented method, states of a multi-core processor are discovered by at least two cores participating in a de-centralized inter-core state discovery process. The inter-core state discovery process is carried out through a combination of microcode executing on each participating core and signals exchanged between the cores through sideband non-system-bus communication wires. The discovery process is unmediated by any centralized non-core logic. Applicable discoverable states include target and composite power states, whether and how many cores are enabled, the availability and distribution of various resources, and hierarchical structures and coordination systems for the cores.

Abstract: Microprocessors are provided with decentralized logic and associated methods for indicating power related operating states, such as desired voltages and frequency ratios, to shared microprocessor power resources such as a voltage regulator module (VRM) and phase locked loops (PLLs). Each core is configured to generate a value to indicate a desired operating state of the core. Each core is also configured to receive a corresponding value from each other core sharing the applicable resource, and to calculate a composite value compatible with the minimal needs of each core sharing the applicable resource. Each core is further configured to conditionally drive the composite value off core to the applicable resource based on whether the core is designated as a master core for purposes of controlling or coordinating the applicable resource. The composite value is supplied to the applicable shared resource without using any active logic outside the plurality of cores.

Abstract: An apparatus is provided that compensates for misalignment on a synchronous data bus. The apparatus includes a Joint Test Action Group (JTAG) interface, a synchronous bus optimizer, and a delay-locked loop (DLL). The JTAG interface is configured to receive control information over a standard JTAG bus, where the control information indicates an amount to delay a data bit signal associated with a data group. The synchronous bus optimizer is configured to receive the control information, and is configured to develop a value on a ratio bus that indicates the amount. The DLL is coupled to the ratio bus, and is configured generate a delayed data bit signal, where the DLL adds the amount of delay to the data bit signal to generate the delayed data bit signal.

Abstract: An apparatus is provided that compensates for misalignment on a synchronous data bus. The apparatus includes a resistor network, a composite delay element, and delay-locked loops (DLLs). The resistor network is configured to provide a ratio signal that indicates an amount to delay data bit signals associated with a data group. The composite delay element is configured to equalize delay paths within a receiving device, where the delay paths correspond to a data strobe signal that is received from a transmitting device. The receiving device and resistor network are coupled to a motherboard. The ratio signal enters said receiving device through an external pin. The DLLs are coupled to the ratio signal and disposed within the receiving device, and are configured to generate delayed data bit signals, where the DLLs add the amount of delay to the data bit signals to generate the delayed data bit signals.

Abstract: An apparatus includes a Joint Test Action Group (JTAG) interface, a synchronous bus optimizer, a core clocks generator, and a synchronous strobe driver. The JTAG interface is configured to receive control information over a standard JTAG bus, where the control information indicates an amount to advance a synchronous data strobe associated with a data group. The synchronous bus optimizer is configured to receive the control information, and is configured to develop a value on a ratio bus that indicates the amount. The core clocks generator is coupled to the ratio bus and is configured to advance a data strobe clock by the amount. The synchronous strobe driver is configured to receive the data strobe clock, and is configured to employ the data strobe clock to generate the synchronous data strobe, where the synchronous data strobe, when enabled, is advanced also by the amount.

Abstract: A first reticle set designed for manufacturing dies with a limited number of cores is modified into a second reticle set suitable for manufacturing at least some dies with at least twice as many cores. The first reticle set defines scribe lines to separate the originally defined dies. At least one scribe line is removed from pairs of adjacent but originally distinctly defined dies. Inter-core communication wires are defined to connect the adjacent cores, which are configured to enable the adjacent cores to communicate during operation without connecting to any physical input/output landing pads of the resulting more numerously cored die, which will not carry signals through the inter-core communication wires off the P-core die. The inter-core communication wires may be used for power management coordination purposes or to bypass the external processor bus.

Abstract: An apparatus that compensates for misalignment on a synchronous data bus, including a resistor network, a transmitting device, and a receiving device. The resistor network indicates an amount to advance a synchronous data strobe associated with a data group. The transmitting device has a core clocks generator and a synchronous strobe driver. The core clocks generator advances a data strobe clock by the amount. The synchronous strobe driver employs the data strobe clock to generate the synchronous data strobe, where the synchronous data strobe is advanced also by the amount. The receiving device has a composite delay element and delay-locked loops (DLLs). The composite delay element equalizes delay paths within the receiving device, where the delay paths correspond to the synchronous data strobe that is received from the transmitting device.

Abstract: A first reticle set designed for manufacturing dies with a limited number of cores is modified into a second reticle set suitable for manufacturing at least some dies with at least twice as many cores. The first reticle set defines scribe lines to separate the originally defined dies. At least one scribe line is removed from pairs of adjacent but originally distinctly defined dies. Inter-core communication wires are defined to connect the adjacent cores, which are configured to enable the adjacent cores to communicate during operation without connecting to any physical input/output landing pads of the resulting more numerously cored die, which will not carry signals through the inter-core communication wires off the P-core die. The inter-core communication wires may be used for power management coordination purposes or to bypass the external processor bus.

Abstract: A multi-core processor provides a configurable resource shared by two or more cores, wherein configurations of the resource affect the power, speed, or efficiency with which the cores sharing the resource are able to operate. Internal core power state management logic configures each core to participate in a de-centralized inter-core power state discovery process to discover a composite target power state for the shared resource that is a most restrictive or power-conserving state that will not interfere with any of the corresponding target power states of each core sharing the resource. The internal core power state management logic determines whether the core is a master core authorized to configure the resource, and if so, configures that resource in the discovered composite power state. The de-centralized power state discovery process is carried out between the cores on sideband, non-system bus wires, without the assistance of centralized non-core logic.

Abstract: Microprocessors are provided with decentralized logic and associated methods for indicating power related operating states, such as desired voltages and frequency ratios, to shared microprocessor power resources such as a voltage regulator module (VRM) and phase locked loops (PLLs). Each core is configured to generate a value to indicate a desired operating state of the core. Each core is also configured to receive a corresponding value from each other core sharing the applicable resource, and to calculate a composite value compatible with the minimal needs of each core sharing the applicable resource. Each core is further configured to conditionally drive the composite value off core to the applicable resource based on whether the core is designated as a master core for purposes of controlling or coordinating the applicable resource. The composite value is supplied to the applicable shared resource without using any active logic outside the plurality of cores.

Abstract: A microprocessor includes two or more processing cores each configured to determine, at each of succeeding instances in time, an amount of energy consumed by the microprocessor during a period preceding the instance in time. The period is predetermined. Each core also operates at a frequency above a predetermined frequency in response to determining the amount of energy consumed is less than a predetermined amount of energy. All of the cores may operate above the predetermined frequency simultaneously until one of the cores determines the microprocessor has consumed more than the predetermined amount of energy during the period preceding the instance in time. The predetermined frequency may be: a frequency at which all the cores can operate over the predetermined period without the microprocessor consuming more than the predetermined amount of energy, or alternatively the maximum frequency at which system software may request the cores to operate.

Abstract: A microprocessor including a temperature sensor that monitors a temperature of core logic of the microprocessor during operation thereof, and operating point information from which may be determined N operating points at which the microprocessor core may reliably operate at a first temperature. Each of the N operating points has a different combination of operating frequency and voltage. The N operating points comprise a highest operating point, a lowest operating point, and a plurality of operating points intermediate the highest and lowest operating points. The microprocessor also includes a control circuit that transitions operation of the core logic among the N operating points to attempt to keep the operating temperature of the core logic provided by the temperature sensor within a temperature range whose upper bound is the first temperature.

Abstract: A microprocessor includes a bus interface unit that interfaces the microprocessor to a bus that includes a signal that, when asserted, instructs all bus agents to refrain from initiating bus transactions. Microcode causes the bus interface unit to assert the signal in response to detecting an event and resets the microprocessor, but does not reset a portion of the bus interface unit that asserts the signal on the bus. After the reset, the microcode causes the bus interface unit to deassert the signal on the bus. Additionally, the microcode sets a flag and saves the microprocessor state to memory before resetting itself, but does not reset the interrupt controller. After the reset, the microcode reloads the state of the microprocessor from the memory. However, if the microcode determines that the flag is set, it forgoes reloading the state of the interrupt controller.

Abstract: A microprocessor is configured to communicate with other agents on a system bus and includes a cache memory and a bus interface unit coupled to the cache memory and to the system bus. The bus interface unit receives from another agent coupled to the system bus a transaction to read data from a memory address, determines whether the cache memory is holding the data at the memory address in an exclusive state (or a shared state in certain configurations), and asserts a hit-modified signal on the system bus and provides the data on the system bus to the other agent when the cache memory is holding the data at the memory address in an exclusive state. Thus, the delay of an access to the system memory by the other agent is avoided.

Abstract: An apparatus is provided that compensates for misalignment on a synchronous data bus. The apparatus includes a resistor network, a core clocks generator, and a synchronous strobe driver. The resistor network is configured to provide a ratio signal that indicates an amount to advance a synchronous data strobe associated with a data group. The core clocks generator is coupled to the ratio signal, and is configured to advance a data strobe clock by the amount. The synchronous strobe driver is configured to receive the data strobe clock, and is configured to employ the data strobe clock to generate the synchronous data strobe, where the synchronous data strobe, when enabled, is advanced also by the amount.