Abstract: A system and method for performing functional verification of a device, and in particular a technique for performing phase-locked loop (PLL) functional verification by the device which contains the PLL circuitry. A relatively slow-speed external clock is provided to the device, and is used to generate control signals to a counter. PLL circuitry within the device generates a relatively high-speed master clock signal for use by the device. This master clock signal is coupled to a clock input of the counter, the counter having various control inputs that are used to selectively count clock pulses of the master clock. As the frequency of the external clock signal is known, and the master clock signal is generated from known PLL circuitry, it is possible to analyze the count value from the counter to determine whether the PLL circuitry used to generate the master clock is operating properly.

Abstract: In-band firmware executes instructions which cause commands to be sent on a coherency fabric. Fabric snoop logic monitors the coherency fabric for command packets that target a resource in one of the support chips attached via an FSI link. Conversion logic converts the information from the fabric packet into an FSI protocol. An FSI command is transmitted via the FSI transmit link to an FSI slave of the intended support chip. An FSI receive link receives response data from the FSI slave of the intended support chip. Conversion logic converts the information from the support chip received via the FSI receive link into the fabric protocol. Response packet generation logic generates the fabric response packet and returns it on the coherency fabric. An identical FSI link between a support processor and support chips allows direct access to the same resources on the support chips by out-of-band firmware.

Abstract: A method and apparatus are provided for a support interface for memory-mapped resources. A support processor sends a sequence of commands over and FSI interface to a memory-mapped support interface on a processor chip. The memory-mapped support interface updates memory, memory-mapped registers or memory-mapped resources. The interface uses fabric packet generation logic to generate a single command packet in a protocol for the coherency fabric which consists of an address, command and/or data. Fabric commands are converted to FSI protocol and forwarded to attached support chips to access the memory-mapped resource, and responses from the support chips are converted back to fabric response packets. Fabric snoop logic monitors the coherency fabric and decodes responses for packets previously sent by fabric packet generation logic. The fabric snoop logic updates status register and/or writes response data to a read data register. The system also reports any errors that are encountered.

Abstract: A method and system for dynamic characterization observability using functional clocks for system or run-time process characterization. Silicon characterization circuitry may be read after silicon chips have been assembled in a package and installed in a system. A characterization circuit comprising one or more oscillators generates signal pulses, wherein the signal pulses represent a frequency of a circuit in the processor chip. A sampler circuit is connected to the characterization circuit, wherein the sampler circuit counts the number of the signal pulses from the characterization circuit within a predetermined time period. A control unit is connected to the sampler circuit, wherein the control unit comprises macros for collecting count data from the one or more oscillators to determine the silicon characterization. Based on the silicon characterization, the optimal operating frequency of the processor chip may be identified, as well as possible lifetime degradation of circuits on the chip.