dm9000驱动代码流程分析

下面详细看下这个入口函数&＃xff08;在driver.cpp中实现&＃xff09;&＃xff1a;在这个函数中主要有一个NdisMInitializeWrapper()&＃xff0c;这个函数的作用就是notifies NDIS that a new miniport is initializing。此函数在ndis.dll中提供&＃xff0c;直接调用就可以。接下来就是给NDIS40_MINIPORT_CHARACTERISTICS这个结构体变量初始化&＃xff0c;主要是设置一些回调函数&＃xff08;MiniportInitialize&＃xff0c;MiniportReset&＃xff0c;MiniportInterruptHandler&＃xff0c;MiniportISRHandler&＃xff0c;MiniportQueryInformation&＃xff0c;MiniportSetInformation&＃xff0c;MiniportSend&＃xff09;&＃xff0c;很明显这些函数有些要自己实现的。再下来就是NdisMRegisterMiniport()了&＃xff0c;This function registers an NIC or intermediate driver&＃39;s Miniport_* entry points and name with the NDIS library when the driver initializes。就是用刚才初始化的那个结构体注册。在public/common/oak/drivers/netsamp/passthru/miniport.c中微软提供了一系列Miniportxxxx函数的实现范例。help中对MiniportInitialize的解释是&＃xff1a;This function is a required function that sets up a network adapter, or virtual network adapter, for network I/O operations, claims all hardware resources necessary to the network adapter in the registry, and allocates resources the driver needs to carry out network I/O operations.

不用问&＃xff0c;接下来就是MiniportInitialize了。在其中有NIC_DRIVER_OBJECT类的初始化&＃xff0c;以及该类的EDriverInitialize函数调用&＃xff0c;在此函数中全面展开了dm9000的所有初始化操作。主要是通过DeviceEntry()这个函数来实现&＃xff08;这个函数实现在dm9000.cpp文件中&＃xff09;&＃xff0c;在DeviceEntry这个函数中只做了一件事&＃xff1a;new了一个C_DM9000类的实例并return。接下来就该C_DM9000的实例表演了&＃xff08;表演场地为上文提到的EDriverInitialize函数中&＃xff09;&＃xff1a;DeviceSetDefaultSettings();DeviceSetEepromFormat();DeviceRetriveConfigurations(hconfig);EDeviceValidateConfigurations()等等&＃xff0c;一套非常漂亮的动作耍完之后又轮到NIC_DRIVER_OBJECT了&＃xff0c;它只是个主持人&＃xff0c;宣布下一个节目是DriverStart()&＃xff08;舞台在MiniportInitialize中&＃xff09;&＃xff0c;实际上表演人还是C_DM9000。其实C_DM9000的表演也很简单但是比较重要&＃xff0c;它在此DeviceEnableInterrupt()启动了中断&＃xff0c;接下来就是无休止的等待&＃xff0c;接收&＃xff0c;发送了。从此踏上了不归路.....