Methods, systems, and devices for post error correction code (ECC) registers for cache metadata are described. A device may read metadata from a memory array included in the device. The metadata may include information for operating a volatile memory as a cache for a non-volatile memory. The device may perform an ECC operation on the metadata based on reading the metadata from the memory array. After performing the ECC operation on the metadata, the device may write the metadata to a register that is coupled with the memory array. The device may then write the metadata from the register to the memory array.

Methods, apparatus, systems and articles of manufacture are disclosed for allocation in a victim cache system. An example apparatus includes a first cache storage, a second cache storage, a cache controller coupled to the first cache storage and the second cache storage and operable to receive a memory operation that specifies an address, determine, based on the address, that the memory operation evicts a first set of data from the first cache storage, determine that the first set of data is unmodified relative to an extended memory, and cause the first set of data to be stored in the second cache storage.

A method for storing data includes determining, using a first match line, that a match word satisfies a first content addressable memory (CAM) word stored in a CAM array, wherein the CAM array is configured to store a second CAM word that matches the first CAM word. The method further includes determining that a first parity bit associated with the first CAM word matches a first parity of the first CAM word. The method further includes, in response to determining that the first parity bit associated with the first CAM word matches the first parity determining, using the first match line, a first random access memory (RAM) word stored in a RAM array and outputting the first RAM word.

An apparatus and method are described for detecting and correcting data fetch errors within a processor core. For example, one embodiment of an instruction processing apparatus for detecting and recovering from data fetch errors comprises: at least one processor core having a plurality of instruction processing stages including a data fetch stage and a retirement stage; and error processing logic in communication with the processing stages to perform the operations of: detecting an error associated with data in response to a data fetch operation performed by the data fetch stage; and responsively performing one or more operations to ensure that the error does not corrupt an architectural state of the processor core within the retirement stage.

In described examples, a processor system includes a processor core that generates memory write requests, a cache memory, and a memory pipeline of the cache memory. The memory pipeline has a holding buffer, an anchor stage, and an RMW pipeline. The anchor stage determines whether a data payload of a write request corresponds to a partial write. If so, the data payload is written to the holding buffer and conforming data is read from a corresponding cache memory address to merge with the data payload. The RMW pipeline has a merge stage and a syndrome generation stage. The merge stage merges the data payload in the holding buffer with the conforming data to make merged data. The syndrome generation stage generates an ECC syndrome using the merged data. The memory pipeline writes the data payload and ECC syndrome to the cache memory.

The operational continuity of a programmable device, and a controller using the same is enhanced. A programmable device is configured with: an error check mechanism that detects, and notifies an error from redundantized user logic blocks; a previous value retaining section that is connected to an output terminal of a last user logic block, and takes in, and outputs an output value of the user logic blocks in each control period; a CRAM check section that receives a scan interrupt due to an error occurrence notification received from the error check mechanism, reads a scan region on the CRAM, implements error detection, and error correction, and notifies a success or failure of the error correction; and an error handling section that transmits an instruction for retaining a previous output of the user logic blocks to the previous value retaining section when the error occurrence notification is received, transmits an instruction for cancelling previous-value retention to the previous value retaining section, and also transmits a logical reset instruction to a user logic block relevant to an error when a notification of a success of the error correction is received from the CRAM check section.

Disclosed in the present invention are a method and a system for ensuring the failure atomicity in a non-volatile memory, which belong to the field of computer storage. The method comprises: executing transactions encapsulated by one or more operations that need to ensure the failure atomicity in accordance with the following steps: executing operations in a current transaction in sequence, for each write operation in the current transaction, determining whether the oldest value of its corresponding data is saved into a log of the non-volatile memory, if so, then creating an UndoRedo log entry for it, otherwise creating a Redo log entry for it; using corresponding log management strategies according to types of log entries; after all operations are executed, committing the current transaction; and completing the execution of the current transaction; wherein information recorded in the UndoRedo log entries comprises: transaction number, write operation address, and oldest value and new value of corresponding data; and information recorded in the Redo log entries comprises: transaction number, write operation address, and new value of corresponding data. The present invention can reduce the overhead caused by ensuring the failure atomicity in the NVMM.

A cache control apparatus includes a data unit configured to store data on an index-specific basis, a tag unit configured to store, on the index-specific basis, a tag and a flag indicating whether the data has an uncorrectable error, and a control unit configured to refer to the flag, upon detecting a tag hit by performing a read access to the tag unit, to determine whether an uncorrectable error exists in the data corresponding to the tag hit, wherein the control unit performs process scheduling such that the read access to the tag unit and another access to the tag unit are performed simultaneously.

Methods, apparatus, systems and articles of manufacture are disclosed facilitate read-modify-write support in a coherent victim cache with parallel data paths. An example apparatus includes a random-access memory configured to be coupled to a central processing unit via a first interface and a second interface, the random-access memory configured to obtain a read request indicating a first address to read via a snoop interface, an address encoder coupled to the random-access memory, the address encoder to, when the random-access memory indicates a hit of the read request, generate a second address corresponding to a victim cache based on the first address, and a multiplexer coupled to the victim cache to transmit a response including data obtained from the second address of the victim cache.

A system and method for caching memory request verification data comprising a memory request generator configured to generate a memory request designating requested data and memory request verification data. A bus is configured to carry the memory request from the memory request generator to a cache memory that stores verification data, and upon receiving the memory request is configured to: retrieve stored verification data from the cache memory, compare the stored verification data to the memory request verification data, and responsive to a match between the stored verification data to the memory request verification data, designate a memory request validation. Also part of the system is a memory controller configured to, responsive to a memory request validation, retrieve data specified in the memory request from a main memory and provide the data to the memory request generator over the bus. A main memory configured to store the requested data.