Abstract: This document generally describes systems, devices, methods, and techniques for obtaining debug information from a memory device. Debug information can include a variety of information associated with a memory device that can be used for debugging the device, such as a sequence of operations performed by the memory device and information regarding errors that have occurred (e.g., type of error, component of memory device associated with error). A memory device can be instructed by a host to obtain and provide debug information to the host. A memory device can be configured to obtain particular debug information using a variety of features, such as triggers. For instance, a memory device can use a trigger to collect debug information related to failed erase operations.

Abstract: In a managed memory subsystem, information associated with the memory subsystem is copied from volatile memory in the memory subsystem to host system memory. The copying can be over a standard interface. Responsive to memory subsystem power up from a powered down state or power loss, the information is copied from the host system memory back to the volatile memory in the memory subsystem, where the information can be used by the memory subsystem to perform memory operations. Transferring information from host system memory to volatile memory in a memory subsystem is faster and more power efficient than transferring the same information from non-volatile memory to volatile memory in the memory subsystem.

Abstract: In one implementation, a memory subsystem includes non-volatile memory, a memory controller that is communicatively connected to the non-volatile memory over a first bus, a host interface through which the memory controller communicates with a host controller over a second bus, and a joint test action group (JTAG) interface that provides the host controller with access to state information associated with the memory controller. The memory subsystem can be configured to be coupled to a board-level memory device that includes the host controller.

Abstract: The disclosed architecture uses address mapping to map a block address on a host interface to an internal block address of a non-volatile memory (NVM) device. The block address is mapped to an internal chip select for selecting a Concurrently Addressable Unit (CAU) identified by the block address. The disclosed architecture supports generic NVM commands for read, write, erase and get status operations. The architecture also supports an extended command set for supporting read and write operations that leverage a multiple CAU architecture.

Abstract: Systems and methods are disclosed for mount-time reconciliation of data availability. During system boot-up, a non-volatile memory (“NVM”) driver can be enumerated, and an NVM driver mapping can be obtained. The NVM driver mapping can include the actual availability of LBAs in the NVM. A file system can then be mounted, and a file system allocation state can be generated. The file system allocation state can indicate the file system's view of the availability of LBAs. Subsequently, data availability reconciliation can be performed. That is, the file system allocation state and the NVM driver mapping can be overlaid and compared with one another in order to expose any discrepancies.

Abstract: Systems and methods for writing to high-capacity memory are disclosed. In high-capacity memory systems in which the capacity of the characteristic portion of the memory (e.g., a page of NAND flash memory) exceeds the capacity of a buffer used to write to the memory, underutilization issues are prevalent. Data organized in the buffer can be combined with additional data to improve utilization of the characteristic portion. According to various embodiments, the additional data can include duplicate copies of the data, whitened data, or any other suitable type of data.

Abstract: Systems and processes may be used to retrieve metadata from a nonvolatile memory of a portable device and transmit the retrieved metadata to an external host. Metadata may be analyzed using the external host and/or at least a portion of the metadata may be modified based on the analysis. Modified metadata may be transmitted from the external host to a memory controller of the host.

Abstract: Systems and methods are disclosed for generating efficient reads for a system having non-volatile memory (“NVM”). A read command can be separated by a host processor of the system into two phases: a) transmitting a command to a storage processor of the system, where the command is associated with one or more logical addresses, and b) generating data transfer information. The host processor can generate the data transfer information while the storage processor is processing the command from the host processor. Once the data transfer information has been generated and data has been read from the NVM, the data can be transferred.

Abstract: A file system programs metadata on a non-volatile memory device. The metadata can include data associating files with ranges of logical block addresses. During a garbage collection process, the data can be used to determine portions of physical blocks of the non-volatile memory device that are associated with files that have been deleted. Using the programmed metadata during garbage collection results in erasure of larger portions of blocks and improved wear leveling.

Abstract: Multipage preparation commands for non-volatile memory systems are disclosed. The multipage preparation commands supply data that can be used to prepare a non-volatile memory device for forthcoming multipage program operations. A host controller can use the commands ahead of a multipage program operation to optimize usage of a multipage program command. The non-volatile memory device can use the commands to configure the non-volatile memory in preparation for a subsequent operation, such as changing a command order or using the most optimized command set for the subsequent operation.

Abstract: Systems and methods are disclosed for mount-time reconciliation of data availability. During system boot-up, a non-volatile memory (“NVM”) driver can be enumerated, and an NVM driver mapping can be obtained. The NVM driver mapping can include the actual availability of LBAs in the NVM. A file system can then be mounted, and a file system allocation state can be generated. The file system allocation state can indicate the file system's view of the availability of LBAs. Subsequently, data availability reconciliation can be performed. That is, the file system allocation state and the NVM driver mapping can be overlaid and compared with one another in order to expose any discrepancies.

Abstract: Systems and methods are provided for improved communications in a nonvolatile memory (“NVM”) system. The system can toggle between multiple communications channels to provide point-to-point communications between a host device and NVM dies included in the system. The host device can toggle between multiple communications channels that extend to one or more memory controllers of the system, and the memory controllers can toggle between multiple communications channels that extend to the NVM dies. Power islands may be incorporated into the system to electrically isolate system components associated with inactive communications channels.

Abstract: Systems and processes may be used to retrieve metadata from a nonvolatile memory of a portable device and transmit the retrieved metadata to an external host. Metadata may be analyzed using the external host and/or at least a portion of the metadata may be modified based on the analysis. Modified metadata may be transmitted from the external host to a memory controller of the host.

Abstract: Systems and processes may use a host and an external host. The host may be a portable device that includes a memory, a memory controller, and a communication interface for communication with the external host. The portable device may receive a command signal from the external host and initiate a predetermined amount of wear leveling in response to the command signal.

Abstract: In one implementation, a memory device includes non-volatile memory, a memory controller communicatively coupled to the non-volatile memory over a first bus, and a host interface through which the memory controller communicates with a host device over a second bus. The memory device can also include a signal conditioner of the host interface adapted to condition signals to adjust a signal level of signals received over the second bus based on signal level data received from the host device, wherein the signal level data relates to a voltage level of signals generated by the host device to encode data transmitted across the second bus.

Abstract: In one implementation, a method includes receiving, at a memory device, an instruction to boot the memory device, wherein the memory device includes non-volatile memory accessible by a controller of the memory device; and, in response to receiving the instruction to boot the memory device, obtaining, by the memory device, firmware from a host device, wherein the host device is separate from and communicatively coupled to the memory device. The method can also include booting the memory device using the firmware from the host device, wherein the memory device boots separately from the host device, and the host device performs operations using data or instructions stored in the non-volatile memory and obtained through communication with the memory controller of the memory device.

Abstract: Systems and processes may use a host and an external host. The host may be a portable device that includes a memory, a memory controller, and a communication interface for communication with the external host. The portable device may receive a command signal from the external host and initiate a predetermined amount of wear leveling in response to the command signal.

Abstract: Systems and methods are provided for improved communications in a nonvolatile memory (“NVM”) system. The system can toggle between multiple communications channels to provide point-to-point communications between a host device and NVM dies included in the system. The host device can toggle between multiple communications channels that extend to one or more memory controllers of the system, and the memory controllers can toggle between multiple communications channels that extend to the NVM dies. Power islands may be incorporated into the system to electrically isolate system components associated with inactive communications channels.

Abstract: In a non-volatile memory system, physically separate power rails are provided from a host system to a NVM device for independently power cycling a controller and memory array in the NVM device. The controller of the NVM device can send a power cycle request signal to the host system over a host channel, or updates a status register in the NVM device. The host system receives and decodes the power cycle request signal, or reads the status register, and performs the power cycle request, which can include power cycling the controller or the memory array in the NVM device, or both. The power cycle request can be based on a power state of the non-volatile memory system, which can be managed by the controller or the host system, or both.

Abstract: Systems and methods are disclosed for usage of a flag bit to suppress data transfer in a mass storage system having non-volatile memory (“NVM”). In some embodiments, a host of the system can issue queue-able trim commands by dispatching non-data transfer write commands to the NVM. In some embodiments, the host can track the read behavior of a particular application over a period of time. As a result, the host can maintain heuristics of logical sectors that are most frequently read together. The host can then notify the NVM to pre-fetch data that the application will most likely request at some point in the future. These notifications can take the form of non-data transfer read commands. Each non-data transfer read commands can include a flag bit that is set to indicate that no data transfer is desired.