| Patent application number | Description | Published |
|---|
| 20080222489 | APPARATUS FOR IMPLEMENTING PROCESSOR BUS SPECULATIVE DATA COMPLETION - A method, and apparatus are provided for implementing processor bus speculative data completion in a computer system. A memory controller in the computer system sends uncorrected data from a memory to a processor bus. The memory controller also applies the uncorrected data to error correcting code (ECC) checking and correcting circuit. When a single bit error (SBE) is detected, corrected data is sent to the processor bus a predefined number of cycles after the uncorrected data. | 09-11-2008 |
| 20080270870 | Memory Controller and Method for Implementing Minimized Latency and Maximized Reliability When Data Traverses Multiple Buses - A memory controller and methods implement minimized latency and maximized reliability when data traverses multiple buses. The memory controller includes a dynamic random access memory (DRAM) error correcting code (ECC) checking and correcting circuit and a high speed bus (HSB) ECC checking and correcting circuit. In a first mode for implementing minimized latency, read data is applied directly to the DRAM ECC checking and correcting circuit, bypassing the HSB ECC checking and correcting circuit. In a second mode for implementing maximized reliability, the read data is applied though the HSB ECC checking and correcting circuit to the DRAM ECC checking and correcting circuit. | 10-30-2008 |
| 20080271054 | Computer System, Computer Program Product, and Method for Implementing Dynamic Physical Memory Reallocation - A computer system, computer program product, and method implement dynamic physical memory reallocation. A system management interface (SMI) Handler and an Operating System (OS) are arranged for exchanging communications. Periodically the SMI Handler queries the operating system to identify a percentage of available memory currently being utilized. Responsive to the identified percentage of available memory currently being utilized, physical memory is dynamically reallocated. | 10-30-2008 |
| 20090019238 | Memory Controller Read Queue Dynamic Optimization of Command Selection - A memory controller receives read requests from a processor into a read queue. The memory controller dynamically modifies an order of servicing the requests based on how many pending requests are in the read queue. When the read queue is relatively empty, requests are serviced oldest first to minimize latency. When the read queue becomes fuller, requests are serviced in a manner that maximizes throughput on a memory bus to reduce the likelihood that the read queue will become full and further requests from the processor would have to be halted. | 01-15-2009 |
| 20090019239 | Memory Controller Granular Read Queue Dynamic Optimization of Command Selection - A memory controller receives read requests from a processor into a read queue. The memory controller dynamically modifies an order of servicing the requests based on how many pending requests are in the read queue. When the read queue is relatively empty, requests are serviced oldest first to minimize latency. When the read queue becomes progressively fuller, requests are progressively, using three or more memory access modes, serviced in a manner that increases throughput on a memory bus to reduce the likelihood that the read queue will become full and further requests from the processor would have to be halted. | 01-15-2009 |
| 20090024807 | MEMORY CONTROLLER AND METHOD FOR OPTIMIZED READ/MODIFY/WRITE PERFORMANCE - A memory controller optimizes execution of a read/modify/write command by breaking the RMW command into separate and unique read and write commands that do not need to be executed together, but just need to be executed in the proper sequence. The most preferred embodiments use a separate RMW queue in the controller in conjunction with the read queue and write queue. In other embodiments, the controller places the read and write portions of the RMW into the read and write queue, but where the write queue has a dependency indicator associated with the RMW write command in the write queue to insure the controller maintains the proper execution sequence. The embodiments allow the memory controller to translate RMW commands into read and write commands with the proper sequence of execution to preserve data coherency. | 01-22-2009 |
| 20090024808 | MEMORY CONTROLLER AND METHOD FOR OPTIMIZED READ/MODIFY/WRITE PERFORMANCE - A memory controller optimizes execution of a read/modify/write command by breaking the RMW command into separate and unique read and write commands that do not need to be executed together, but just need to be executed in the proper sequence. The most preferred embodiments use a separate RMW queue in the controller in conjunction with the read queue and write queue. In other embodiments, the controller places the read and write portions of the RMW into the read and write queue, but where the write queue has a dependency indicator associated with the RMW write command in the write queue to insure the controller maintains the proper execution sequence. The embodiments allow the memory controller to translate RMW commands into read and write commands with the proper sequence of execution to preserve data coherency. | 01-22-2009 |
| 20090070647 | Scheduling of Background Scrub Commands to Reduce High Workload Memory Request Latency - A method and apparatus to scrub a memory during a scrub period, of a computer system. The computer system has a memory controller that receives read requests and write requests from a processor. The memory controller provides a different priority for scrub requests versus read requests during a period of relatively light memory workload versus a period of relatively heavy workload. The memory controller provides a relatively higher priority for scrub requests near an end of a scrub period if scrub progress is behind an expected scrub progress. | 03-12-2009 |
| 20090070648 | Efficient Scheduling of Background Scrub Commands - A method and apparatus to efficiently scrub a memory, during a scrub period, of a computer system that has a memory comprising a number of memory elements. Examples of memory elements are memory ranks and banks. A memory rank may further comprise one or more banks. The computer system has a memory controller that receives read requests and write requests from a processor. The memory controller includes a scrub controller configured to output more than one scrub request during a particular request selector cycle. The memory controller includes a request selector that services a read request, a write request, or one of the scrub requests during a request selector cycle. | 03-12-2009 |
| 20090132876 | Maintaining Error Statistics Concurrently Across Multiple Memory Ranks - A method and apparatus to maintain memory read error information concurrently across multiple ranks in a computer memory. An error detection unit associates a read error with a particular rank and with a particular chip in the rank. The error detection unit reports the error and the associated rank ID and chip ID to an error logging unit. The error logging unit maintains, for each rank ID and chip ID for which an error has been detected, a total number of errors that occur. A memory controller uses a fault pattern in the error logging unit to replace failing memory chips or memory ranks with a spare memory chip or a spare memory rank. | 05-21-2009 |
| 20090177946 | Memory Initialization Time Reduction - A method and apparatus to improve memory initialization in a memory of a computer system. Memory units in the memory comprise a plurality of ranks, each rank having a unique rank select. A parity generator outputs a parity bit corresponding to whether an encoded rank select has an even or odd number of “1”s. The parity bit is used by an Error Checking and Correcting (ECC) unit that generates ECC bits that are stored in a rank having an active rank select. During a first interval in a memory initialization period, ranks having an even number of “1”s in their encoded rank select are initialized in parallel. During a second interval in the memory initialization period, ranks having an odd number of “1”s in their encoded rank select are initialized in parallel. | 07-09-2009 |
| 20090216959 | Multi Port Memory Controller Queuing - The present invention is generally directed to a method, system, and program product wherein at least one command in a first queue is transferred to a second queue. When the first queue can no longer accept command(s) and a second queue is able to accept command(s), the second queue accepts the command(s) that the first queue can not. When the first queue is able to accept command(s), and there are command(s) in the second memory port that should have been in the first queue, the command(s) in the second queue are transferred to the first queue. | 08-27-2009 |
| 20090216960 | Multi Port Memory Controller Queuing - The present invention is generally directed to a method, system, and program product wherein at least two memory ports associated within a memory controller are capable of transferring commands between one another in unbalanced memory configurations. When the first memory port can no longer accept commands and a second memory port is able to accept commands, the second memory port accepts the commands that the first memory port can not. When the first memory port is able to accept commands, and there are commands in the second memory port that should have been in the first memory port, the commands in the second memory port are transferred to the first memory port. | 08-27-2009 |
| 20090287900 | Reducing Power-On Time by Simulating Operating System Memory Hot Add - This invention generally provides a method for speeding up system boot time, by initializing a subset of memory during the system firmware test/initialization, and allowing the system to boot an operating system with this subset of installed memory. While the system is completing the operating system boot with the subset of installed memory, a remainder of the installed system memory is being initialized/tested. When the initialization the remainder of system memory is completed (and after the OS has booted), the SMI handler is invoked. The SMI handler then simulates a physical memory “Hot Add” event, and reports the event to the OS. This allows much of the memory initialization/test activity to occur in parallel with the firmware initialization/test and operating system startup processes. | 11-19-2009 |
| 20110119439 | Spacing Periodic Commands to a Volatile Memory for Increased Performance and Decreased Collision - A periodic command spacing mechanism is provided for spacing periodic commands (e.g., refresh commands, ZQ calibration, etc.) to a volatile memory (e.g., SDRAM, DRAM, EDRAM, etc.) for increased performance and decreased collision. In one embodiment, periodic command requests are monitored and if a collision is detected between two or more of the requests, the colliding requests are spaced with respect to one another by a timer offset applied on a chip select basis. The periodic command spacing mechanism may be used in conjunction with command arbitration to make sure the periodic commands are executed without significantly impacting performance (e.g., Reads and Writes are allowed to flow). Preferably, the periodic command requests are initialized by generating an initial sequence of individual requests, each successive request in the initial sequence being generated spaced apart with respect to the previous request by a timer offset applied on a chip select basis. | 05-19-2011 |
