Abstract: A method and apparatus for managing write-to-read turnarounds in an early read after write memory system are presented. Memory controller logic identifies a write operation's bank set, allows a different bank set read operation to issue prior to the write operation's completion, and allows a same bank set read operation to issue once the write operation completes. The memory controller includes operation counter logic, operation selection logic, operation acceptance logic, command formatting logic, and memory interface logic. The operation counter logic receives new-operation-related signals from the operation acceptance logic and, in turn, provides signals to the operation selection logic and the operation acceptance logic as to when to issue a read operation that corresponds to either an even DRAM bank or an odd DRAM bank.

Abstract: A method, an apparatus, and a computer program are provided to reuse functional data buffers. With Extreme Data Rate (XDR™) Dynamic Random Access Memory (DRAM), test patterns are employed to dynamically calibrate data with the clock. To perform this task, data buffers are employed to store data and commands for the calibration patterns. However, there are different procedures and requirements for transmission and reception calibrations. Hence, to reduce the amount of hardware needed to perform transmission and reception calibrations, the data buffers employ additional front end circuitry to reuse the buffers for both tasks.

Abstract: In a first aspect, a method of testing or analyzing an integrated circuit (IC) is provided. The method includes the steps of (1) generating information about a dependency between components of the IC based on a netlist describing the IC; and (2) reducing the generated information by at least one of (a) combining portions of the information about components with a common dependency; and (b) eliminating a portion of the information about at least a first component that does not depend on another component of the IC. Numerous other aspects are provided.

Abstract: A method, an apparatus, and a computer program product are provided for the handling of write mask operations in an XDR DRAM memory system. This invention eliminates the need for a two-port array because the mask generation is done as the data is received. Less logic is needed for the mask calculation because only 144 of the 256 possible byte values are decoded. The mask value is generated and stored in a mask array. Independently, the write data is stored in a write buffer. The mask value is utilized to generate a write mask command. Once the write mask command is issued, the write data and the mask value are transmitted to a multiplexer. The multiplexer masks the write data using the mask value, so that the masked data can be stored in the XDR DRAMS.

Abstract: A method and apparatus for managing write-to-read turnarounds in an early read after write memory system are presented. Memory controller logic identifies a write operation's bank set, allows a different bank set read operation to issue prior to the write operation's completion, and allows a same bank set read operation to issue once the write operation completes. The memory controller includes operation counter logic, operation selection logic, operation acceptance logic, command formatting logic, and memory interface logic. The operation counter logic receives new-operation-related signals from the operation acceptance logic and, in turn, provides signals to the operation selection logic and the operation acceptance logic as to when to issue a read operation that corresponds to either an even DRAM bank or an odd DRAM bank.

Abstract: A method, an apparatus, and a computer program are provided to reuse functional data buffers. With Extreme Data Rate (XDR™) Dynamic Random Access Memory (DRAM), test patterns are employed to dynamically calibrate data with the clock. To perform this task, data buffers are employed to store data and commands for the calibration patterns. However, there are different procedures and requirements for transmission and reception calibrations. Hence, to reduce the amount of hardware needed to perform transmission and reception calibrations, the data buffers employ additional front end circuitry to reuse the buffers for both tasks.

Abstract: A method, an apparatus, and a computer program are provided to account for data stored in Dynamic Random Access Memory (DRAM) write buffers. There is difficulty in tracking the data stored in DRAM write buffers. To alleviate the difficulty, a cache line list is employed. The cache line list is maintained in a memory controller, which is updated with data movement. This list allows for ease of maintenance of data without loss of consistency.

Abstract: An arbitration structure, a method, and a computer program are provided for an arbitration scheme that can handle a plurality of memory commands in an operating system. Typically, in a memory system there are three types of memory commands: periodic, read, and write. An arbitration scheme determines the order of priority in which these commands are executed. This arbitration scheme is flexible because it contains a read/write priority module, which can be programmed to execute any order of priority combination of read and write commands. This enables an arbitration scheme for any memory system to be easily programmed for maximum efficiency.

Abstract: In a first aspect, a first method is provided for self-adjusting allocation of memory bandwidth in a network processor system. The first method includes the steps of (1) determining an amount of memory bandwidth of a network processor used by each of a plurality of data types; and (2) dynamically adjusting the amount of memory bandwidth allocated to at least one of the plurality of data types based on the determination. Numerous other aspects are provided.

Abstract: A method, apparatus and computer program product are provided for implementing virtual packet storage via packet work area (PWA) in a network processor system. A mapping area including a packet work area and a corresponding set of packet segment registers (PSRs) are provided. A PSR is loaded with a Packet ID (PID) and a packet translation unit maps the packet data into the corresponding PWA. The PWA address defining an offset into the packet is translated into a physical address. The packet translation unit redirects loads and stores of the PWA into the correct data buffer or buffers in system memory. Packets include one or more data buffers that are chained together, using a buffer descriptor providing the packet physical address. The buffer descriptor points to a data buffer for the packet and to a next buffer descriptor.