The present disclosure relates to methods and systems for implementing redundancy in memory controllers. The disclosed systems and methods utilize a row of memory blocks, such that each memory block in the row is associated with an independent media unit. Failures of the media units are not correlated, and therefore, a failure in one unit does not affect the data stored in the other units. Parity information associated with the data stored in the memory blocks is stored in a separate memory block. If the data in a single memory block has been corrupted, the data stored in the remaining memory blocks and the parity information is used to retrieve the corrupted data.

A storage system has a memory with a multi-level cell (MLC) block and a partially-bad single-level cell (SLC) block. The storage system repurposes the partially-bad SLC block as a non-volatile read cache for data stored in the MLC block (e.g., cold data that is read relatively frequently) to improve performance of host reads. Because the original version of the data is still stored in the MLC block, the original version of the data can be read if there is an error in the copy of the data stored in the partially-bad SLC block, thus avoiding the need for extensive error-correction handling to account for the poor reliability of the partially-bad SLC block.

A method of failure mapping is provided. The method includes determining that a non-volatile memory block in the memory has a defect and generating a mask that indicates the non-volatile memory block and the defect. The method includes reading from the non-volatile memory block with application of the mask, wherein the reading and the application of the mask are performed by the non-volatile solid-state storage.

A memory system and a data processing system including the memory system may manage a plurality of memory devices. For example, the data processing system may categorize and analyze error information from the memory devices, acquire characteristic data from the memory devices and set operation modes of the memory devices based on the characteristic data, allocate the memory devices to a host workload, detect a defective memory device among the memory devices and efficiently recover the defective memory device.

A memory controller includes a memory interface and a processor. The processor is coupled to the memory interface and controls access operation of a memory device via the memory interface. The processor maintains a predetermined table according to write operation of a first memory block of the memory device and performs data protection in response to the write operation. When performing the data protection, the processor determines whether memory space damage has occurred in the first memory block. When it is determined that memory space damage has occurred in the first memory block, the processor traces back one or more data sources of data written in the first memory block according to the predetermined table to obtain address information of one or more source memory blocks and performs a data recovery operation according to the address information of the one or more source memory blocks.

A scheme for handling program errors is provided for a memory system which includes a memory device and a controller including firmware and a memory interface. The firmware issues commands for program operations to the memory interface. After detecting a failed program operation in a particular memory block, the firmware reroutes that program operation to a different location in a different memory block and takes further action to reduce the likelihood of a subsequent error occurring in the same memory block in which the failed program operation occurred.

The present disclosure provides a content addressable memory (CAM) for repairing firmware of multi-plane read operations in a flash memory device. The CAM comprises a set of CAM registers configured to store a mapping table. The mapping table comprises a plurality of old addresses, each old address corresponding to a new address. The CAM also comprises N comparators coupling to the set of CAM registers, and configured to compare the old addresses with N input signals for performing the multi-plane read operations on N memory planes, wherein N is an integer greater than 1. The CAM further comprises N multiplexers coupling to the N comparators respectively and to the set of CAM registers, and configured to generate N output signals for the multi-plane read operations. At least one of the N output signals comprises the new address according to the mapping table and a comparison output by the comparators.

A data storage device includes a non-volatile memory (NVM) device and a controller coupled to the NVM device. The controller is configured to create a bad block table that tracks bad blocks of the NVM device, send the bad block table to a host memory location, and check the bad block table to determine whether a block to be read or written to is bad. The controller is further configured to request information on a bad block from the bad block table located in the host memory location, determine that the requested information is not available from the host memory location, and retrieve the requested information from a location separate from the host memory location. A sum of the times to generate a request to check the flat relink table, execute the request, and retrieve the requested information is less than a time to process a host command.

A non-volatile data storage device includes memory cells arranged in a plurality of blocks and a memory controller coupled to the memory cells for controlling operations of the memory cells. The memory controller is configured to determine if a given block is a bad m-bit multi-level block. In an m-bit multi-level block, each memory cell is an m-bit multi-level cell (MLC), m being an integer equal to or greater than 2. Upon determining that the given block is a good m-bit multi-level block, the memory controller assigns the given block to be an m-bit multi-level user block. Upon determining that the given block is a bad m-bit multi-level block, the memory controller determines if the given block is a good n-bit block. In an n-bit block, each memory cell is an n-bit cell, n being an integer less than m. Upon determining that the given block is a good n-bit block, the memory controller assigns the given block to be an n-bit user block or an n-bit write-buffer block.

An indirection mapping data structure can maintain a mapping between logical block addresses used by a host computer and physical data storage locations on a solid state drive. Changes to the indirection mapping data structure can be stored in journals. When a journal is full, the journal can be stored to a predetermined location on the cluster block determined based on the number of entries stored by the journal, leading to a number of journals scattered throughout the cluster block at predetermined locations. Each physical chunk of media, whether written with data or marked as defective is journaled. Such a journaling scheme, where the journal locations are predetermined and each physical chunk of media is journaled is referred to as physical media-aware spatially coupled journaling. During replay the spatially coupled journals can be retrieved from the predefined locations within cluster blocks and used to rebuild the indirection mapping data structure.