公开(公告)号：US06397316B2

公开(公告)日：2002-05-28

申请号：US08899435

申请日：1997-07-24

申请人： Nestor A. Fesas, Jr.

发明人： Nestor A. Fesas, Jr.

IPC分类号： G06F1210

CPC分类号： H04L12/40032 ,  H04L12/40006

摘要： The present invention provides a method and an apparatus for transferring data between a computer system and a network interface card that avoids virtual-to-physical address translations. The computer system allocates blocks of memory during system initialization for storing data in transit between the computer system and the NIC, and the physical addresses of these blocks of memory are stored in a table on the NIC. Consequently, address conversion is performed only once, when the memory is allocated. When a request to transfer data to the NIC is received from the upper layers, the device driver copies the data from the upper layers into the next available memory block. The device driver then formats a command and passes it to the NIC for processing. Data transfer commands are communicated to the NIC through a packet descriptor command (PDC), which is a 32-bit value subdivided into fields that completely describe the data transfer operation. The PDC contains a small ordinal value that indexes a table in the NIC, which includes a set of physical addresses of buffers preallocated by the computer system in the computer system memory. These buffers are used for storing data in transit to the NIC. The PDC also contains the length of the buffer to be copied to or from the NIC. The present invention also allows for multiple packets to be formatted into buffers and then subsequently transferred to the NIC in a single I/O operation.

摘要翻译： 本发明提供一种用于在计算机系统和网络接口卡之间传送数据的方法和装置，其避免虚拟到物理地址转换。 计算机系统在系统初始化期间分配存储器块以存储计算机系统和NIC之间的传输数据，并且这些存储器块的物理地址存储在NIC的表中。 因此，当分配存储器时，地址转换只执行一次。 当从上层接收到向NIC传送数据的请求时，设备驱动程序将数据从上层复制到下一个可用的存储块中。 然后，设备驱动程序格式化命令并将其传递给NIC进行处理。 数据传输命令通过分组描述符命令（PDC）传送给网卡，分组描述符命令（PDC）是一个32位值，被细分为完全描述数据传输操作的字段。 PDC包含索引NIC中的表的小序数值，其中包括计算机系统内存中由计算机系统预分配的缓冲区的一组物理地址。 这些缓冲区用于存储传输到NIC的数据。 PDC还包含要从NIC复制的缓冲区的长度。 本发明还允许将多个分组格式化为缓冲器，然后在单个I / O操作中随后传送到NIC。

公开(公告)号：US06516352B1

公开(公告)日：2003-02-04

申请号：US09135074

申请日：1998-08-17

申请人： Bradley J. Booth ,  Nestor A. Fesas, Jr. ,  Robert O. Sharp ,  William Kass

发明人： Bradley J. Booth ,  Nestor A. Fesas, Jr. ,  Robert O. Sharp ,  William Kass

IPC分类号： G06F1516

CPC分类号： H04L12/403

摘要： A system and method for dynamically switching between different physical layer devices (PHYs) in a network interface. The system comprises a network interface in a network device, e.g., a network card in a computer system which includes a first PHY device and a second PHY device. The first PHY device is coupled to a first transmission medium (such as fiber-optic cable) which requires a continuous connection to the computer system when active. For a SERDES device, this continuous connection is required because the PHY needs constant access to its physical coding sublayer (PCS), which is located external to the PHY. The second PHY device is coupled to a second transmission medium (such as copper cable) which does not require this continuous connection. This second PHY may be, for example, a G/MII device, which includes the PCS internally. The network interface card further includes a link switching unit, a physical layer interface unit, and a control unit. The control unit generates a select signal indicating which physical layer device is currently selected. Accordingly, the link switching unit transfers data between the physical layer interface unit and the currently selected physical layer device. The physical layer interface unit receives incoming data from either the link switching unit or an external interface of the network interface card. The physical layer interface unit includes two sub-layers corresponding to each of the physical devices. These sub-layers each produce outgoing data in response to the incoming data, and the appropriate outgoing data is chosen based on the currently selected physical layer device.

摘要翻译： 一种用于在网络接口中动态切换不同物理层设备（PHY）的系统和方法。 该系统包括网络设备中的网络接口，例如包括第一PHY设备和第二PHY设备的计算机系统中的网卡。 第一PHY设备耦合到第一传输介质（例如光纤电缆），其在活动时需要连续连接到计算机系统。 对于SERDES设备，需要这种连续连接，因为PHY需要对其位于PHY外部的物理编码子层（PCS）的持续访问。 第二PHY设备耦合到不需要这种连续连接的第二传输介质（例如铜缆）。 该第二PHY可以是例如在内部包括PCS的G / MII设备。 网络接口卡还包括链路切换单元，物理层接口单元和控制单元。 控制单元产生指示当前选择哪个物理层设备的选择信号。 因此，链路切换单元在物理层接口单元和当前选择的物理层设备之间传送数据。 物理层接口单元从链路交换单元或网络接口卡的外部接口接收输入数据。 物理层接口单元包括与每个物理设备相对应的两个子层。 这些子层各自响应于输入数据产生输出数据，并且基于当前选择的物理层设备选择适当的输出数据。