Abstract: In a first aspect, a first method of interfacing a processor and memory is provided. The first method includes the steps of (1) providing a computer system including (a) a memory; (b) a processor adapted to issue a functional command to the memory; (c) a translation chip; (d) a first link adapted to couple the processor to the translation chip; and (e) a second link adapted to couple the translation chip to the memory; (2) calibrating the first link using the translation chip; and (3) while calibrating the first link, calibrating the second link using the translation chip. Numerous other aspects are provided.

Abstract: In a first aspect, a first method of interfacing a processor and memory is provided. The first method includes the steps of (1) providing a computer system including (a) a first memory; (b) a processor adapted to issue a functional command to the first memory; (c) a translation chip; (d) a cache memory coupled to the translation chip; (e) a first link adapted to couple the processor to the translation chip; and (f) a second link adapted to couple the translation chip to the first memory; and (2) calibrating the first link to transmit data between the processor and cache memory. Numerous other aspects are provided.

Abstract: In a first aspect, a first method of controlling a non-functional operation on a memory of a computer system using software is provided. The first method includes the steps of (1) employing a processor to write bits of data to at least one register external to the processor, wherein the bits of data serve as control bits for the memory; and (2) applying the bits of data to respective pins of the memory so as to cause the non-functional operation to be performed on the memory. Numerous other aspects are provided.

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, apparatus and computer program product are provided for implementing a pointer and stake model for frame alteration code in a network processor. A current pointer and a stake are provided for a packet selected for transmit. The current pointer is maintained for tracking a current position for frame alteration operations in the packet. The stake is maintained for tracking a start of a current header for frame alteration operations in the packet. The current pointer is used by frame alteration code instructions to specify a sequence of operations relative to the current pointer. The specified frame alteration sequence is compact in terms of code size to operate on data within a small window of bytes. Advance pointer instructions allow the current and stake pointers to be advanced an arbitrary number of bytes into the packet.

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, apparatus and computer program product are provided for implementing a pointer and stake model for frame alteration code in a network processor. A current pointer and a stake are provided for a packet selected for transmit. The current pointer is maintained for tracking a current position for frame alteration operations in the packet. The stake is maintained for tracking a start of a current header for frame alteration operations in the packet. The current pointer is used by frame alteration code instructions to specify a sequence of operations relative to the current pointer. The specified frame alteration sequence is compact in terms of code size to operate on data within a small window of bytes. Advance pointer instructions allow the current and stake pointers to be advanced an arbitrary number of bytes into the packet.

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: The present invention provides a way to offload trace data from a processor and store the trace data in external memory. By accumulating trace data in large buffers and sending them to a memory interface controller, the memory interface controller may write trace data to memory as the memory interface controller would execute a normal write to memory. In this manner, no additional I/O memory pins are required and processor memory storage for trace data is kept to a minimum. Furthermore, by using a special port to the memory interface controller the writing of trace data may be accomplished in a manner that does not affect the speed of the on-chip bus between the processor and the memory interface controller.

Abstract: Embodiments of the present invention optimize data bandwidth across an asynchronous buffer in a system with a variable clock domain. A move signal may be asserted to transfer data associated with a command into the asynchronous buffer. After the data has been moved into the buffer, an acknowledge signal may indicate that the transfer is complete. A launch signal may transfer the data in the asynchronous buffer to memory. Embodiments of the present invention allow the processing of a next command to begin at the earliest possible time while data associated with a previous command is being transferred into and out of the buffer, thereby increasing throughput and improving performance.

Abstract: The present invention generally relates to memory controllers operating in a system containing a variable system clock. The memory controller may exchange data with a processor operating at a variable processor clock frequency. However the memory controller may perform memory accesses at a constant memory clock frequency. Asynchronous buffers may be provided to transfer data across the variable and constant clock domains. To prevent read buffer overflow while switching to a lower processor clock frequency, the memory controller may quiesce the memory sequencers and pace read data from the sequencers at a slower rate. To prevent write data under runs, the memory controller's data flow logic may perform handshaking to ensure that write data is completely received in the buffer before performing a write access.

Abstract: A method and apparatus are provided for implementing frame header alterations on multiple concurrent frames. Each of a plurality of frame data alteration engines includes a pair of a command decoder and an associated data aligner. A command buffer arbiter sequentially receives frame alteration commands and sequentially selects one of the frame data alteration engines for the sequentially received frame alteration commands. Each command decoder receives and decodes frame alteration commands and provides frame alignment commands and alteration instructions and each associated data aligner receives frame data and selectively latches data bytes of the received frame data responsive to the frame alignment commands and sequentially provides an aligned frame data output of a predefined number of bytes.

Abstract: A method and apparatus are provided for implementing frame header alterations using byte-wise arithmetic logic units (ALUs). First and second stage alteration engines include a plurality of first stage byte-wise arithmetic logic units (ALUs). Each ALU includes inputs for receiving frame data, command data, register data, and commands, and register data and data outputs. The first and second stage byte-wise ALUs respectively perform the received first and second stage commands and the second stage ALUs provide altered frame data output. The commands enable operations such as load, add, and, or, move, and the like used by the two-stages of byte-wise ALUs forming the alteration engines to perform the alterations or combine new header data into a stream of frame data.

Abstract: In a first aspect, a first method is provided for adjusting memory system calibration. The first method includes the steps of (1) while in a first operating state, calibrating the memory system using a first amount of calibration data so that functional data may be read from and written to memory of the memory system; and (2) while in a second operating state, calibrating the memory system using a second amount of calibration data so that functional data may be read from and written to the memory, wherein the second amount of calibration data is smaller than the first amount of calibration data. Numerous other aspects are provided.

Abstract: A method and apparatus are provided for implementing frame header alterations in a network processor. A command decoder receives and decodes frame alteration commands and provides frame alignment commands and alteration instructions. A data aligner receives frame data and is coupled to the command decoder receiving the frame alignment commands. The data aligner includes an insert and delete unit that sequentially receives a predefined number of bytes of frame data, selectively latches data bytes of the received predefined number of bytes of frame data responsive to the frame alignment commands and sequentially provides an aligned frame data output of the predefined number of bytes. An alteration engine is coupled to the data aligner receiving the sequential aligned frame data output and is coupled to the command decoder receiving the alteration instructions. The alteration engine provides sequential altered frame data responsive to the received alteration instructions.

Abstract: In a first aspect, a first method is provided for adjusting memory system calibration. The first method includes the steps of (1) while in a first operating state, calibrating the memory system using a first amount of calibration data so that functional data may be read from and written to memory of the memory system; and (2) while in a second operating state, calibrating the memory system using a second amount of calibration data so that functional data may be read from and written to the memory, wherein the second amount of calibration data is smaller than the first amount of calibration data. Numerous other aspects are provided.

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.