Abstract: Systems and methods are provided to improve a communication channel dynamically and autonomously based on the status of the communication traffic on the communication channel between a first integrated circuit (IC) and a second IC. The communication traffic on the communication channel can be monitored, and latency, bandwidth, link quality, or power consumption associated with the communication channel for the monitored communication traffic can be determined dynamically. A modified protocol for the communication channel that can improve the communication channel as compared to an existing protocol can be determined based on the information related to the latency, bandwidth, link quality, or the power consumption. The existing protocol can be changed autonomously to the modified protocol as the communication traffic varies.

Abstract: An interposer circuit is used between an interrupt controller and a processor core to facilitate direct injection of a virtual interrupt into a guest executing on the processor core, even though the interrupt controller does not support the direct injection. The interposer circuit can convert a command received from the interrupt controller for a physical interrupt into another command for a virtual interrupt to make the processor core believe that the processor core has received a virtual interrupt even though the interrupt controller is not able to provide the virtual interrupt. The virtual interrupt can be directly injected into the processor core without the intervention of a hypervisor executing on the processor core.

Abstract: Systems and methods are disclosed to provide an autonomous management of communication links between dice on a multi-die assembly. Each die can include a detection unit and a controller to detect a failing communication link and perform link maintenance by directing the communication traffic on the failing link to an operational link before the link fails. Once the failing link has been repaired, the controller can re-direct the traffic back to the repaired link. The controllers on each die can negotiate through a handshake process to provide the continuous operation by switching the communication traffic from the failing link to the operational link, and then from the operational link to the repaired link.

Abstract: A memory controller can receive transactions from an interconnect to access the memory. The memory controller can use a credit-based scheme to request the interconnect to send specific memory transactions that can be scheduled in a desirable order using a credit type associated with each transaction. In some embodiments, the memory controller can keep track of the number of transactions directed to each bank of the memory based on a credit type, so that specific transactions directed towards the underutilized banks can be requested and scheduled in a manner to utilize all the banks more uniformly to improve the system performance.

Abstract: Techniques for encoding additional data in a memory without requiring an increase to the physical storage capacity of the memory device are described. Additional data can be encoded with error correction code symbols without having to physically store the additional data in memory, while retaining the number of error correction code bits used by the memory. When data is read from memory without the additional data, erasure decoding can be performed to recover the additional data. When errors are encountered in the data read from memory, the errors can be treated as erasures for different predictions of the error locations to determine if the errors can be corrected.

Abstract: Systems, apparatuses, and corresponding techniques are described for selective erasure decoding on memory devices. Erasure decoding is performed on error correction codes (ECCs) read from memory locations associated with errors that are correctable through erasure decoding, as indicated by erasure information available to a memory controller or other device configured to decode ECCs. The erasure information can indicate locations within individual memory devices and, optionally, at different memory hierarchy levels. When the erasure information indicates that a location being read from is not associated with an error that is correctable through erasure decoding, regular error decoding is performed on ECCs read from such locations. Selective erasure decoding can be performed in connection with separate read operations that access different memory devices or a single read operation that accesses multiple memory devices concurrently.

Abstract: A dedicated input/output (I/O) cache can be used for I/O-to-processor communications. Data received from an I/O device can be written to the I/O cache and also written to a device memory that is accessible to the processor. The processor can then access the data in the fast, dedicated I/O cache if available. Otherwise, the processor can read the data from the memory into a conventional processor cache for processing. Writes to the cache can be full or partial, with partial writes utilizing padding in some embodiments. The data can be written sequentially in a circular manner. Data processed by the processor can be invalidated, and invalidated data can be overwritten on a subsequent write. Phase bits can also be used to indicate the pass during which various writes were performed.

Abstract: An interposer circuit is used between an interrupt controller and a processor core to facilitate direct injection of a virtual interrupt into a guest executing on the processor core, even though the interrupt controller does not support the direct injection. The interposer circuit can convert a command received from the interrupt controller for a physical interrupt into another command for a virtual interrupt to make the processor core believe that the processor core has received a virtual interrupt even though the interrupt controller is not able to provide the virtual interrupt. The virtual interrupt can be directly injected into the processor core without the intervention of a hypervisor executing on the processor core.

Abstract: An integrated circuit includes first and second cores. Each core has a power-switchable portion in a first power domain in which an operating power is turned on or off in response to a power control signal. The first power domain includes a first scan chain, and the first power domain also includes a plurality of outputs. Each core also includes an always-on portion in a second power domain in which the operating power is maintained during testing of the integrated circuit. The second power domain also has a second scan chain. The second power domain further includes respective isolation gates coupled to the plurality of outputs of the first power domain, and the second scan chain includes a respective wrapper cell coupled to some isolation gates. The integrated circuit is configured to power off and isolate the power-switchable portion in the first power domain based on a scan test result.

Abstract: In a memory controller, a prefetch indication can be sent to memory to prepare the memory for a potential future read or write. Statistics can be used to select when such a prefetch should occur. The prefetch can occur without any read or write command being commenced. As a result, the memory controller predicts when to perform the prefetch. Some examples of when a prefetch can be sent include when there are other requests for the same memory page, or how often the page is requested. The page can remain open to prevent it from closing until the relevant read or write arrives. In the case that a read or write does not occur after a predetermined period of time, then a precharge can be performed to release the memory page.

Abstract: A method and circuit are disclosed to calculate an error correction code (ECC) and perform a decompression in parallel when reading memory data. There are multiple modes of operation. In a normal parallel mode of operation, the data passes through a decompression engine. Simultaneously, the same data passes through an ECC decode engine. However, if no error is detected, the output of the decode engine is discarded. If there is an ECC error, an error indication is made so that the corresponding data exiting the decompression engine is discarded. The circuit then switches to a serial mode of operation, wherein the ECC decode engine corrects the data and resends the corrected data again through the decompression engine. The circuit is maintained in the serial mode until a decision is made to switch back to the parallel mode, such as when a pipeline of the ECC engine becomes empty.

Abstract: A method and circuit are disclosed to calculate an error correction code (ECC) and perform a decryption in parallel when reading memory data. There are multiple modes of operation. In a normal parallel mode of operation, the data passes through a decryption engine. Simultaneously, the same data passes through an ECC decode engine. However, if no error is detected, the output of the decode engine is discarded. If there is an ECC error, an error indication is made so that the corresponding data exiting the decryption engine is discarded. The circuit then switches to a serial mode of operation, wherein the ECC decode engine corrects the data and resends the corrected data again through the decryption engine. The circuit is maintained in the serial mode until a decision is made to switch back to the parallel mode, such as when a pipeline of the ECC engine becomes empty.

Abstract: Disclosed herein is a distributed performance monitor circuit that includes a plurality of performance monitors connected to a cross-trigger network. Each performance monitor corresponds to a respective functional block of a system and includes a counter circuit. The counter circuit includes a programmable time window counter configured to determine an adjustable counting period, and an event counter configured to count a number of occurrences of an event occurring in the respective functional block during the counting period. The cross-trigger network is configured to receive an output trigger signal generated by a performance monitor when the number of occurrences of the event occurring in the corresponding functional block during the counting period is outside of a threshold band for the performance monitor, and send an input trigger signal to the plurality of performance monitors based on receiving the output trigger signal.

Abstract: Provided are methods and adapter devices for buffering write transactions directed to a large space. In various implementations, an adapter device may include a sequential address buffer and a memory. A region of the memory may be configured as a data block, which may be associated with an address range. The address range may correspond to a region of an address space of a target device. The adapter device may be configured to receive a write transaction, the write transaction having an address and data. The adapter device may further write the address to the sequential address buffer. The adapter device may further determine that the address is within the address range, and to write the data to the data block. The adapter device may further, upon the occurrence of an event, write the data from the data block to the region of the address space of the target device.

Abstract: Disclosed herein is a performance monitor for a functional block of a system, the performance monitor comprising a counter circuit, wherein the counter circuit includes a programmable time window counter configured to determine an adjustable counting period, and an event counter coupled to the time window counter. The event counter is configured to count a number of occurrences of an event occurring in the functional block during the counting period, and record the number of occurrences of the event during the counting period and generate an output trigger signal when the number of occurrences of the event during the counting period is outside of a programmable threshold band, or after receiving an input trigger signal from a cross trigger network triggered by other performance monitors in electrical communication with the cross trigger network.

Abstract: Provided are systems and methods for distributing ordering tasks in a computing system that includes master and target devices. In some implementations, a computing device is provided. The computing device may include a master device that is operable to initiate transactions. The computing device may further include a target device that is operable to receive transactions. In some implementations, the master device may be configured to transmit one or more transactions to the target device. The master device may further asynchronously indicate to the target device a number of transactions to execute. The master device may further asynchronously receive from the target device a number of transactions executed. The master device may then signal that at least one transaction from the one or more transactions it sent has completed.