Abstract: Flexible command addressing for memory. An embodiment of a memory device includes a dynamic random-access memory (DRAM); and a system element coupled with the DRAM, the system element including a memory controller for control of the DRAM. The DRAM includes a memory bank, a bus, the bus including a plurality of pins for the receipt of commands, and a logic, wherein the logic provides for shared operation of the bus for a first type of command and a second type of command received on a first set of pins.

Abstract: Embodiments are generally directed to validation of memory on-die error correction code. An embodiment of a memory device includes one or more memory arrays for the storage of data; control logic to control operation of the memory device; and ECC (error correction code) logic, including ECC correction logic to correct data and ECC generation logic to generate ECC code bits and store the ECC bits in the one or more memory arrays. In a validation mode to validate operation of the ECC logic, the control logic is to allow generation of ECC code bits for a first test value and disable generation of ECC code bits for a second test value.

Abstract: Techniques and mechanisms to facilitate an operational mode of a memory device to prepare for a targeted refresh of a row in memory. In an embodiment, the memory device performs one or more operations while in the mode to prepare for a future command from a memory controller, the command to implement, at least in part, a targeted refresh of a row in a first bank of the memory device. Prior to such a command, the memory device services another command from the memory controller. In another embodiment, servicing the other command includes the memory device accessing a second bank of the memory device while the memory device operates in the mode, and before completion of an expected future targeted row refresh.

Abstract: A memory controller issues a targeted refresh command. A specific row of a memory device can be the target of repeated accesses. When the row is accessed repeatedly within a time threshold (also referred to as “hammered” or a “row hammer event”), physically adjacent row (a “victim” row) may experience data corruption. The memory controller receives an indication of a row hammer event, identifies the row associated with the row hammer event, and sends one or more commands to the memory device to cause the memory device to perform a targeted refresh that will refresh the victim row.

Abstract: A memory subsystem enables managing error correction information. A memory device internally performs error detection for a range of memory locations, and increments an internal count for each error detected. The memory device includes ECC logic to generate an error result indicating a difference between the internal count and a baseline number of errors preset for the memory device. The memory device can provide the error result to an associated host of the system to expose only a number of errors accumulated without exposing internal errors from prior to incorporation into a system. The memory device can be made capable to generate internal addresses to execute commands received from the memory controller. The memory device can be made capable to reset the counter after a first pass through the memory area in which errors are counted.

Abstract: Memory subsystem refresh management enables commands to access one or more identified banks across different bank groups with a single command. Instead of sending commands identifying a bank or banks in separate bank groups by each bank group individually, the command can cause the memory device to access banks in different bank groups. The command can be a refresh command. The command can be a precharge command.

Abstract: Detection logic of a memory subsystem obtains a threshold for a memory device that indicates a number of accesses within a time window that causes risk of data corruption on a physically adjacent row. The detection logic obtains the threshold from a register that stores configuration information for the memory device, and can be a register on the memory device itself and/or can be an entry of a configuration storage device of a memory module to which the memory device belongs. The detection logic determines whether a number of accesses to a row of the memory device exceeds the threshold. In response to detecting the number of accesses exceeds the threshold, the detection logic can generate a trigger to cause the memory device to perform a refresh targeted to a physically adjacent victim row.

Abstract: Embodiments are generally directed to performance of additional refresh operations during self-refresh mode. An embodiment of a memory device includes one or more memory banks, a mode register set, the mode register set including a first set of mode register bits, and a control logic to provide control operations for the memory device, the operations including refresh operations for the one or more memory banks in a refresh credit mode. The control logic is to perform one or more extra refresh cycles in response to receipt of a self-refresh command, the self-refresh command to provide current refresh status information, and is to store information in the first set of mode register bits regarding a modified refresh status after the performance of the one or more extra refresh cycles.

Abstract: Techniques and mechanisms to provide write access to a memory device. In an embodiment, a memory controller sends commands to a memory device which comprises multiple memory banks. The memory controller further sends a signal specifying that the commands include back-to-back write commands each to access the same memory bank. In response to the signal, the memory device buffers first data of a first write command, wherein the first data is buffered at least until the memory device receives second data of a second write command. Error correction information is calculated for a combination of the first data and second data, and the combination is written to the memory bank. In another embodiment, buffering of the first data and combining of the first data with the second data is performed, based on the signal from the memory controller, in lieu of read-modify-write processing of the first data.

Abstract: Techniques and mechanisms for exchanging information between a memory controller and a memory device. In an embodiment, a memory controller receives information indicating for a memory device a threshold number of pending consolidated activation commands to access that memory device. The threshold number indicated by the information is less than a theoretical maximum number of pending consolidated activation commands, the theoretical maximum number defined based on timing parameters of the memory device. In another embodiment, the memory controller limits communication of consolidated activation commands to the memory device based on the information indicating the threshold number.

Abstract: Devices, systems, and methods include an active mode to accommodate read/write operations of a memory device and a self-refresh mode to accommodate recharging of voltage levels representing stored data when read/write operations are idle. At least one register source provides a first voltage level and a second voltage level that is less than the first voltage level. With such a configuration, during the active mode, the memory device operates at the first voltage level as provided by the at least one register source, and during the self-refresh mode, the memory device operates at the second voltage level as provided by the at least one register source.

Abstract: Embodiments are generally directed to performance of additional refresh operations during self-refresh mode. An embodiment of a memory device includes one or more memory banks, a mode register set, the mode register set including a first set of mode register bits, and a control logic to provide control operations for the memory device, the operations including refresh operations for the one or more memory banks in a refresh credit mode. The control logic is to perform one or more extra refresh cycles in response to receipt of a self-refresh command, the self-refresh command to provide current refresh status information, and is to store information in the first set of mode register bits regarding a modified refresh status after the performance of the one or more extra refresh cycles.

Abstract: Embodiments are generally directed to memory refresh operation with page open. An embodiment of a memory device includes a memory array including a plurality of memory banks; and a control logic to provide control operations for the memory device including a page open refresh mode, wherein the control logic is to perform a refresh cycle in response to a refresh command with a memory page of the memory array open, the refresh operation including precharge of one or more memory banks of the plurality of memory banks, refresh of the one or more memory banks, and activation of the memory page.

Abstract: Techniques and mechanisms for exchanging information between a memory controller and a memory device. In an embodiment, a memory controller receives information indicating for a memory device a threshold number of pending consolidated activation commands to access that memory device. The threshold number indicated by the information is less than a theoretical maximum number of pending consolidated activation commands, the theoretical maximum number defined based on timing parameters of the memory device. In another embodiment, the memory controller limits communication of consolidated activation commands to the memory device based on the information indicating the threshold number.

Abstract: Techniques and mechanisms to facilitate an operational mode of a memory device to prepare for a targeted refresh of a row in memory. In an embodiment, the memory device performs one or more operations while in the mode to prepare for a future command from a memory controller, the command to implement, at least in part, a targeted refresh of a row in a first bank of the memory device. Prior to such a command, the memory device services another command from the memory controller. In another embodiment, servicing the other command includes the memory device accessing a second bank of the memory device while the memory device operates in the mode, and before completion of an expected future targeted row refresh.

Abstract: A memory controller issues a targeted refresh command. A specific row of a memory device can be the target of repeated accesses. When the row is accessed repeatedly within a time threshold (also referred to as “hammered” or a “row hammer event”), physically adjacent row (a “victim” row) may experience data corruption. The memory controller receives an indication of a row hammer event, identifies the row associated with the row hammer event, and sends one or more commands to the memory device to cause the memory device to perform a targeted refresh that will refresh the victim row.

Abstract: A check bit read mode enables a memory device to provide internal check bits to an associated host. A memory controller of a memory subsystem can generate one or more read commands for memory devices of the memory subsystem. The read command can include address location information. The memory devices include memory arrays with memory locations addressable with the address location information. The memory locations have associated data and internal check bits, where the check bits are generated internally by the memory for error correction. If the memory device is configured for check bit read mode, in response to the read command, it sends the internal check bits associated with the identified address location. If the memory device is not configured check bit read mode, it returns the data in response to the read command without exposing the internal check bits.

Abstract: An error check and scrub (ECS) mode enables a memory device to perform error checking and correction (ECC) and count errors. An associated memory controller triggers the ECS mode with a trigger sent to the memory device. The memory device includes multiple addressable memory locations, which can be organized in segments such as wordlines. The memory locations store data and have associated ECC information. In the ECS mode, the memory device reads one or more memory locations and performs ECC for the one or more memory locations based on the ECC information. The memory device counts error information including a segment count indicating a number of segments having at least a threshold number of errors, and a maximum count indicating a maximum number of errors in any segment.

Abstract: In a system where a memory device performs on-die ECC, the ECC operates on N-bit data words as two (N/2)-bit segments, with a code matrix having a corresponding N codes that can be operated on as a first portion of (N/2) codes and a second portion of (N/2) codes to compute first and second error checks for first and second (N/2)-bit segments of the data word, respectively. In the code matrix, a bitwise XOR of any two codes in the first portion of the code matrix or any two codes in the second portion of the code matrix results in a code that is either not in the code matrix or is in the other portion of the code matrix. Thus, a miscorrected double bit error in one portion causes a bit to be toggled in the other portion instead of creating a triple bit error.

Abstract: Techniques and mechanisms to facilitate an operational mode of a memory device to prepare for a targeted refresh of a row in memory. In an embodiment, the memory device performs one or more operations while in the mode to prepare for a future command from a memory controller, the command to implement, at least in part, a targeted refresh of a row in a first bank of the memory device. Prior to such a command, the memory device services another command from the memory controller. In another embodiment, servicing the other command includes the memory device accessing a second bank of the memory device while the memory device operates in the mode, and before completion of an expected future targeted row refresh.