System and method for DMA transfer of data in scatter/gather mode
    1.
    发明申请
    System and method for DMA transfer of data in scatter/gather mode 有权
    以分散/收集模式DMA传输数据的系统和方法

    公开(公告)号:US20050027901A1

    公开(公告)日:2005-02-03

    申请号:US10899196

    申请日:2004-07-26

    摘要: A method and system for DMA transfer of data in scatter/gather mode. A table of buffer descriptors may be used to determine the next buffer to be used when a current buffer storing data that has been transferred or will be transferred and may be used in automatic buffer switching, which does not require processor intervention. Entries in the table of buffer descriptors are entered programmatically. The method and system also provide for hardware writing to table of packet descriptors which describes location and size of incoming data and can indicate whether a packet of data straddles two or more buffers, thus decoupling packet sizes from buffer sizes.

    摘要翻译: 用于以分散/收集模式DMA传输数据的方法和系统。 可以使用缓冲器描述符表来确定当存储已被传送或将被传送的数据的当前缓冲器时使用的下一个缓冲器,并且可以用于不需要处理器干预的自动缓冲器切换。 缓冲区描述符表中的条目以编程方式输入。 该方法和系统还提供对描述入站数据的位置和大小的分组描述符的表的硬件写入,并且可以指示数据包是否跨越两个或更多个缓冲器,从而将分组大小与缓冲器大小分离。

    Method for performing single instruction multiple data operations on packed data
    2.
    发明申请
    Method for performing single instruction multiple data operations on packed data 审中-公开
    对打包数据执行单指令多数据操作的方法

    公开(公告)号:US20050027969A1

    公开(公告)日:2005-02-03

    申请号:US10899193

    申请日:2004-07-26

    摘要: Instructions for performing SIMD instructions, including parallel absolute value and parallel conditional move instructions, as well as a method and circuit for saturating results of operations. The parallel absolute value instruction determines the absolute value of operands based on the sign bit of the operands. When a parallel conditional move instruction is executed, status indicators corresponding to an operand are compared to a condition code in a register to determine whether the condition is true for any of the status indicators; if the condition is true, the corresponding operand is moved to a specified register. A method and circuit for handling saturation of a result of an operation are also provided. When two m-bit operands are added, as in an addition, average, or subtraction operation, if an average instruction is executed, the m most significant bits are output; otherwise, the m least significant bits are output and the result is saturated if there is overflow and saturation is enabled.

    摘要翻译: 执行SIMD指令的指令,包括并行绝对值和并行条件移动指令,以及用于饱和运算结果的方法和电路。 并行绝对值指令根据操作数的符号位决定操作数的绝对值。 当执行并行条件移动指令时,将对应于操作数的状态指示符与寄存器中的条件代码进行比较,以确定任何状态指示符的条件是否为真; 如果条件为真,则将相应的操作数移动到指定的寄存器。 还提供了一种用于处理操作结果的饱和度的方法和电路。 当添加两个m位操作数时,如在加法,平均或减法操作中,如果执行平均指令,则输出m个最高有效位; 否则,输出m个最低有效位,并且如果有溢出和饱和使能,结果将饱和。