Abstract: Methods for reducing boot time of a system-on-a-chip (SOC) by reducing double data rate (DDR) memory training and memory context restore. Dynamic random access memory (DRAM) controller and DDR physical interface (PHY) settings are stored into a non-volatile memory and the DRAM controller and DDR PHY are powered down. On system resume, a basic input/output system restores the DRAM controller and DDR PHY settings from non-volatile memory, and finalizes the DRAM controller and DDR PHY settings for operation with the SOC. Reducing the boot time of the SOC by reducing DDR training includes setting DRAMs into self-refresh mode, and programing a self-refresh state machine memory operation (MOP) array to exit self-refresh mode and update any DRAM device state for the target power management state. The DRAM device is reset, and the self-refresh state machine MOP array reinitializes the DRAM device state for the target power management state.

Abstract: Methods for reducing boot time of a system-on-a-chip (SOC) by reducing double data rate (DDR) memory training and memory context restore. Dynamic random access memory (DRAM) controller and DDR physical interface (PHY) settings are stored into a non-volatile memory and the DRAM controller and DDR PHY are powered down. On system resume, a basic input/output system restores the DRAM controller and DDR PHY settings from non-volatile memory, and finalizes the DRAM controller and DDR PHY settings for operation with the SOC. Reducing the boot time of the SOC by reducing DDR training includes setting DRAMs into self-refresh mode, and programing a self-refresh state machine memory operation (MOP) array to exit self-refresh mode and update any DRAM device state for the target power management state. The DRAM device is reset, and the self-refresh state machine MOP array reinitializes the DRAM device state for the target power management state.

Abstract: A memory controller includes a host interface for receiving memory access requests including access addresses, a memory interface for providing memory accesses to a memory system, and an address decoder coupled to the host interface for programmably mapping the access addresses to selected ones of a plurality of regions. The address decoder is programmable to map the access addresses to a first region having a non-power-of-two size using a primary decoder and a secondary decoder each having power-of-two sizes, and providing a first region mapping signal in response. A command queue stores the memory access requests and region mapping signals. An arbiter picks the memory access requests from the command queue based on a plurality of criteria, which are evaluated based in part on the region mapping signals, and provides corresponding memory accesses to the memory interface in response.

Abstract: Systems, apparatuses, and methods for performing efficient memory accesses for a computing system are disclosed. When a memory controller in a computing system determines a threshold number of memory read requests have been sent to a memory device in a read mode of a data bus, the memory controller determines a threshold number of memory write requests to send to the memory device in an upcoming write mode is a number of outstanding memory write requests. Alternatively, the memory controller determines the threshold number of memory write requests to send to the memory device in an upcoming write mode is a maximum value of the number of outstanding memory write requests and a programmable value of the write burst length stored in a control register. Therefore, the write burst length is determined dynamically. Similarly, the read burst length is determined dynamically when the write mode ends.

Abstract: Systems, apparatuses, and methods for performing efficient memory accesses for a computing system are disclosed. In various embodiments, a computing system includes one or more computing resources and a memory controller coupled to a memory device. The memory controller determines a memory access request targets a given bank of multiple banks. An access history is updated for the given bank based on whether the memory access request hits on an open page within the given bank and a page hit rate for the given bank is determined. The memory controller sets an idle cycle limit based on the page hit rate. The idle cycle limit is a maximum amount of time the given bank will be held open before closing the given bank while the bank is idle. The idle cycle limit is based at least in part on a page hit rate for the bank.

Abstract: A system includes a memory system comprising a memory module and a processor adapted to access the memory module using a memory controller that includes a controller having an input for receiving a power state change request signal and an output for providing memory operations, and a memory operation array comprising a plurality of entries. Each entry includes a plurality of encoded fields. The memory operation array is programmable to store different sequences of commands for particular types of memory of a plurality of types of memory in the plurality of entries that initiate entry into and exit from supported low power modes for the particular types of memory. The controller is responsive to an activation of the power state change request signal to access the memory operation array to fetch at least one entry, and to issue at least one memory operation indicated by the at least one entry.

Abstract: In one form, a data processing system includes a memory channel having a plurality of ranks, and a data processor. The data processor is coupled to the memory channel and is adapted to access each of the plurality of ranks. In response to detecting a predetermined event, the data processor selects an active rank of the plurality of ranks and places other ranks besides the active rank in a low power state, wherein the other ranks include at least one rank with a pending request at a time of detection of the predetermined event. The data processor subsequently processes a memory access request to the active rank.

Abstract: In one form, a memory controller includes a controller and a memory operation array. The controller has an input for receiving a power state change request signal and an output for providing memory operations. The memory operation array comprises a plurality of entries, each entry comprising a plurality of encoded fields. The controller is responsive to an activation of the power state change request signal to access the memory operation array to fetch at least one entry, and to issue at least one memory operation indicated by the entry. In another form, a system comprises a memory system and a processor coupled to the memory system. The processor is adapted to access the memory module using such a memory controller.

Abstract: Dynamic random access memory (DRAM) chips in memory modules include multi-purpose registers (MPRs) having pre-defined data patterns which, when selected, are accessed with read commands and output on data lines for performing read training. The MPRs are accessed by issuing read commands to specific register addresses to request reads from specific MPR locations. In some embodiments, read training for memory modules includes addressing, for a first half of a memory module, a read command to a first register address and performing read training using a first set of bit values received in response to addressing using the first register address. For a second half of the memory module, the same read command is used, but read training is performed using a second set of bit values received in response to addressing using the first register address.

Abstract: A post-package repair system includes a memory channel controller, a first error counter, a scrubber, and a data processor. The memory channel controller converts data access requests to corresponding memory accesses, and provides returned data to the host interface in response to responses received from a memory interface, wherein the responses comprise returned data and a plurality of error correcting code (ECC) bits. The first error counter counts errors in the returned data, and provides a control signal in response to reaching a predetermined state. The scrubber controls the memory channel controller to read data sequentially and periodically from a plurality of addresses of a memory system, and in response to detecting a correctable error, to rewrite corrected data. The data processor is responsive to the control signal to perform a post package repair operation with the memory system in response to the control signal.

Abstract: A data processing system includes a memory channel and a data processor coupled to the memory channel. The data processor includes a memory controller coupled to the memory channel and is adapted to access at least one rank of double data rate memory. The memory controller includes a command queue for storing received memory access requests, and an arbiter for picking memory access requests from the command queue, and then providing the memory access requests to the memory channel. The memory access requests are selected based on predetermined criteria, and in response to a mode register access request to quiesce pending operations. Additionally, the memory controller includes a mode register access controller that in response to the mode register access request, generates at least one corresponding mode register set command to a memory bus. The memory controller then relinquishes control of the memory bus to the arbiter thereafter.

Abstract: A data processing system includes a memory channel and a data processor coupled to the memory channel. The data processor includes a memory controller coupled to the memory channel and is adapted to access at least one rank of double data rate memory. The memory controller includes a command queue for storing received memory access requests, and an arbiter for picking memory access requests from the command queue, and then providing the memory access requests to the memory channel. The memory access requests are selected based on predetermined criteria, and in response to a mode register access request to quiesce pending operations. Additionally, the memory controller includes a mode register access controller that in response to the mode register access request, generates at least one corresponding mode register set command to a memory bus. The memory controller then relinquishes control of the memory bus to the arbiter thereafter.

Abstract: Dynamic random access memory (DRAM) chips in memory modules include multi-purpose registers (MPRs) having pre-defined data patterns which, when selected, are accessed with read commands and output on data lines for performing read training. The MPRs are accessed by issuing read commands to specific register addresses to request reads from specific MPR locations. In some embodiments, read training for memory modules includes addressing, for a first half of a memory module, a read command to a first register address and performing read training using a first set of bit values received in response to addressing using the first register address. For a second half of the memory module, the same read command is used, but read training is performed using a second set of bit values received in response to addressing using the first register address.

Abstract: A memory controller includes a host interface for receiving memory access requests including access addresses, a memory interface for providing memory accesses to a memory system, and an address decoder coupled to the host interface for programmably mapping the access addresses to selected ones of a plurality of regions. The address decoder is programmable to map the access addresses to a first region having a non-power-of-two size using a primary decoder and a secondary decoder each having power-of-two sizes, and providing a first region mapping signal in response. A command queue stores the memory access requests and region mapping signals. An arbiter picks the memory access requests from the command queue based on a plurality of criteria, which are evaluated based in part on the region mapping signals, and provides corresponding memory accesses to the memory interface in response.

Abstract: In one form, a memory controller includes a controller and a memory operation array. The controller has an input for receiving a power state change request signal and an output for providing memory operations. The memory operation array comprises a plurality of entries, each entry comprising a plurality of encoded fields. The controller is responsive to an activation of the power state change request signal to access the memory operation array to fetch at least one entry, and to issue at least one memory operation indicated by the entry. In another form, a system comprises a memory system and a processor coupled to the memory system. The processor is adapted to access the memory module using such a memory controller.

Abstract: A post-package repair system includes a memory channel controller, a first error counter, a scrubber, and a data processor. The memory channel controller converts data access requests to corresponding memory accesses, and provides returned data to the host interface in response to responses received from a memory interface, wherein the responses comprise returned data and a plurality of error correcting code (ECC) bits. The first error counter counts errors in the returned data, and provides a control signal in response to reaching a predetermined state. The scrubber controls the memory channel controller to read data sequentially and periodically from a plurality of addresses of a memory system, and in response to detecting a correctable error, to rewrite corrected data. The data processor is responsive to the control signal to perform a post package repair operation with the memory system in response to the control signal.

Abstract: In one form, a data processing system includes a memory channel having a plurality of ranks, and a data processor. The data processor is coupled to the memory channel and is adapted to access each of the plurality of ranks. In response to detecting a predetermined event, the data processor selects an active rank of the plurality of ranks and places other ranks besides the active rank in a low power state, wherein the other ranks include at least one rank with a pending request at a time of detection of the predetermined event. The data processor subsequently processes a memory access request to the active rank.

Abstract: In one form, a memory includes a memory bank, a page buffer, and an access circuit. The memory bank has a plurality of rows and a plurality of columns with volatile memory cells at intersections of the plurality of row and the plurality of columns. The page buffer is coupled to the plurality of columns and stores contents of a selected one of the plurality of rows. The access circuit is responsive to an adjacent command and a row address to perform a predetermined operation on the row address, and to refresh first and second addresses adjacent to the row address. In another form, a memory controller is adapted to interface with such a memory to select either a normal command or an adjacent command based on a number of activate commands sent to the row in a predetermined time window.

Abstract: A data processor includes a memory accessing agent and a memory controller. The memory accessing agent generates a plurality of accesses to a memory. The memory controller is coupled to the memory accessing agent and schedules the plurality of memory accesses in an order based on characteristics of the memory. The characteristics of the memory include a row cycle page time (tRCPAGE) indicative of an acceptable number of activate commands to a row in the memory within a predetermined time window.

Abstract: A method is provided for performing memory operations in response to instructions to perform a double data rate (DDR) memory reference voltage training in the voltage domain by a processing device and determining a DDR memory reference voltage and a DDR memory delay time based upon the memory operation. Computer readable storage media are also provided. A circuit is provided that includes a communication interface portion coupled to a memory and to a processing device. The circuit also includes a circuit portion, coupled to the communication interface portion that has a hardware state machine or an algorithm. The state machine or algorithm provides instructions to the processing device to perform a double data rate (DDR) reference voltage training in the voltage domain.