Abstract: Systems, apparatuses and methods may provide for technology that conducts a comparison between an identified capability of a memory device and memory usage rules associated with a processor. The memory usage rules are to identify allowed memory accesses by the processor. The technology further limits access by the processor to the memory device based upon the comparison.

Abstract: A system provides a mailbox communication register for communication between a host and a mode register. The mode register is to store configuration information, and write of configuration information to the mode register by the host takes less time than a read of the configuration information from the mode register by the host. The communication register is separate from the mode register and provides a location to store the configuration information for a read by the host. In response to a read request by the host, the mode register can copy the configuration information to the communication register and allow the host to read the register based on different timing rules than those that apply to the mode register. Instead of reading directly from a register that has timing variance between read and write, the host can read from a communication register.

Abstract: A semiconductor chip comprising memory controller circuitry having interface circuitry to couple to a memory channel. The memory controller includes first logic circuitry to implement a first memory channel protocol on the memory channel. The first memory channel protocol is specific to a first volatile system memory technology. The interface also includes second logic circuitry to implement a second memory channel protocol on the memory channel. The second memory channel protocol is specific to a second non volatile system memory technology.

Abstract: A memory device with internal row hammer mitigation includes randomization for selection of victim rows to refresh for row hammer mitigation. When memory devices connected in groups all use the same probabilistic determination of which row to select for row hammer mitigation, all memory devices could miss refreshing the same victim row, resulting in data loss. With randomization of the selection, the memory devices are more likely to select different potential victim rows for refresh, reducing the risk of data loss. The memory device performs row hammer mitigation during a refresh operation on a row selected based on a recent activate command. Selection of the victim row can be performed with a pseudo-random computation based on a value unique to the memory device in the group.

Abstract: A computing system is described. The computing system includes a memory controller having a double data rate memory interface. The double data rate memory interface has a first memory channel interface and a second memory channel interface. The computing system also includes a first DIMM slot and a second DIMM slot. The computing system also includes a first memory channel coupled to the first memory channel interface and the first DIMM slot, wherein the first memory channel's CA and DQ wires are not coupled to the second DIMM slot. The computing system also includes a second memory channel coupled to the second memory channel interface and the second DIMM slot, wherein the second memory channel's CA and DQ wires are not coupled to the first DIMM slot. The computing system also includes a back end memory channel that is coupled to the first and second DIMM slots.

Abstract: A DIMM is described. The DIMM includes circuitry to simultaneously transfer data of different ranks of memory chips on the DIMM over a same data bus during a same burst write sequence.

Abstract: A memory subsystem enables per device addressability (PDA) to target configuration commands to one of multiple memory devices that share a select line or buffer devices that share an enable line. The system includes a host and multiple memory devices that can be coupled over a command bus and a data bus. The devices include a configuration or mode register to store a value to indicate whether PDA enumeration is enabled. When enabled, the host can provide an enumeration identifier (ID) command via the command bus with a signal via the data bus to assign an enumeration ID. After assignment of the enumeration ID, the host can send PDA commands via the command bus with the enumeration ID, without a signal on the data bus. Devices only process PDA commands that match their assigned enumeration ID, enabling the setting of device-specific configuration settings without needing to use the data bus on every PDA command.

Abstract: A DIMM is described. The DIMM includes circuitry to multiplex write data to different groups of memory chips on the DIMM during a same burst write sequence.

Abstract: A memory device is described. The memory device includes logic circuitry to perform calibrations of resistive network terminations and data drivers of the memory device while the memory device is within a self refresh mode.

Abstract: An apparatus is described. The apparatus includes a memory controller having register space to inform the memory controller that the memory controller is coupled to a memory module that conforms to a first memory chip industry standard specification but is composed of memory chips that conform to a second, different memory chip industry standard specification.

Abstract: Provided are a method and apparatus for a memory module to accept a command in multiple parts. A first half of a command is placed on a bus for a memory module in a first clock cycle. A chip select signal is placed on the bus for the memory module for the first half of the command. A second half of the command is placed on the bus in a second clock cycle following the first clock cycle, wherein the memory module accepts the second half of the command a delay interval from accepting the first half of the command.

Abstract: A sequence of read returns are to be sent to a host device over a transactional buffered memory interface, where the sequence includes at least a first read return to a first read request and a second read return to a second read request. A tracker identifier of the second read return is encoded in the first read return and the first read return is sent with the tracker identifier of the second read return to the host device. The second read return is sent to the host device after the first read return is sent.

Abstract: Examples may include techniques to use chip select signals for a dual in-line memory module (DIMM). In some examples, the chip select signals are used with either a first encoding scheme for clock enable (CKE) functionality or a second encoding scheme for on-die termination (ODT) functionality to enable memory devices on the DIMM to be accessed or controlled according to commands received with the chip select signals.

Abstract: Provided are a method and apparatus for selecting one of a plurality of bus interface configurations to use. Selection is made of a first bus interface configuration having a first bus width to send data over the bus in response to an interface parameter indicating a first interface parameter. Selection is made of a second bus interface configuration having a second bus width to send data over the bus in response to the interface parameter indicating a second interface parameter, wherein the first bus width has fewer bits than the second bus width.

Abstract: A semiconductor chip comprising memory controller circuitry having interface circuitry to couple to a memory channel. The memory controller includes first logic circuitry to implement a first memory channel protocol on the memory channel. The first memory channel protocol is specific to a first volatile system memory technology. The interface also includes second logic circuitry to implement a second memory channel protocol on the memory channel. The second memory channel protocol is specific to a second non volatile system memory technology.

Abstract: Provided are a method and apparatus for determining a timing adjustment of output to a host memory controller in a first memory module coupled to a host memory controller and a second memory module over a bus. A determination is made of a timing adjustment based on at least one component in at least one of the first memory module and the second memory module. A timing of output to the host memory controller is adjusted based on the determined timing adjustment to match a timing of output at the second memory module.

Abstract: Examples include techniques to access or operate a dual in-line memory module (DIMM) via one or multiple data channels. In some examples, memory devices at or on the DIMM may be accessed via one or more data channels. The one or more data channels arranged such that the DIMM is configured to operate in a dual channel mode that includes two data channels or to operate in a single channel mode that includes a single data channel.

Abstract: A plurality of completed writes to memory are identified corresponding to a plurality of write requests from a host device received over a buffered memory interface. A completion packet is sent to the host device that includes a plurality of write completions to correspond to the plurality of completed writes.

Abstract: A memory subsystem includes a data bus to couple a memory controller to one or more memory devices. The memory controller and one or more memory devices transfer data for memory access operations. The data transfer includes the transfer of data bits and associated check bits over a transfer cycle burst. The memory devices include internal error checking and correction (ECC) separate from the system ECC managed by the memory controller. With a 2N transfer cycle for 2?N data bits for a memory device, the memory devices can provide up to 2N memory locations for N+1 internal check bits, which can leave up to (2N minus (N+1)) extra bits to be used by the system for more robust ECC.

Abstract: A semiconductor chip comprising memory controller circuitry having interface circuitry to couple to a memory channel. The memory controller includes first logic circuitry to implement a first memory channel protocol on the memory channel. The first memory channel protocol is specific to a first volatile system memory technology. The interface also includes second logic circuitry to implement a second memory channel protocol on the memory channel. The second memory channel protocol is specific to a second non volatile system memory technology.