代码收藏家技术教程 2024-09-03

Windows驱动PCIe DMA实例详解

以下是一个更详细的PCIe DMA驱动实现示例：

1. 首先，定义必要的结构和常量：

```c
#include <ntddk.h>
#include <wdf.h>

#define PCIE_DEVICE_ID 0x1234 // 替换为实际的设备ID
#define DMA_BUFFER_SIZE 0x1000 // 4KB

typedef struct _QUEUE_CONTEXT {
WDFQUEUE Queue;
WDFDMAENABLER DmaEnabler;
WDFDMATRANSACTION DmaTransaction;
} QUEUE_CONTEXT, *PQUEUE_CONTEXT;

WDF_DECLARE_CONTEXT_TYPE_WITH_NAME(QUEUE_CONTEXT, QueueGetContext)
```

2. 驱动入口点和设备添加函数：

```c
NTSTATUS DriverEntry(PDRIVER_OBJECT DriverObject, PUNICODE_STRING RegistryPath) {
NTSTATUS status;
WDF_DRIVER_CONFIG config;

WDF_DRIVER_CONFIG_INIT(&config, EvtDeviceAdd);
status = WdfDriverCreate(DriverObject, RegistryPath, WDF_NO_OBJECT_ATTRIBUTES, &config, WDF_NO_HANDLE);

return status;
}

NTSTATUS EvtDeviceAdd(WDFDRIVER Driver, PWDFDEVICE_INIT DeviceInit) {
NTSTATUS status;
WDFDEVICE device;
WDF_OBJECT_ATTRIBUTES deviceAttributes;
WDF_PNPPOWER_EVENT_CALLBACKS pnpPowerCallbacks;

UNREFERENCED_PARAMETER(Driver);

WDF_PNPPOWER_EVENT_CALLBACKS_INIT(&pnpPowerCallbacks);
pnpPowerCallbacks.EvtDevicePrepareHardware = EvtDevicePrepareHardware;
WdfDeviceInitSetPnpPowerEventCallbacks(DeviceInit, &pnpPowerCallbacks);

WDF_OBJECT_ATTRIBUTES_INIT(&deviceAttributes);
status = WdfDeviceCreate(&DeviceInit, &deviceAttributes, &device);
if (!NT_SUCCESS(status)) {
return status;
}

status = QueueInitialize(device);
return status;
}
```

3. 准备硬件和初始化DMA：

```c
NTSTATUS EvtDevicePrepareHardware(WDFDEVICE Device, WDFCMRESLIST ResourceList, WDFCMRESLIST ResourceListTranslated) {
NTSTATUS status;
PQUEUE_CONTEXT queueContext;
WDF_DMA_ENABLER_CONFIG dmaConfig;
WDFQUEUE queue;

UNREFERENCED_PARAMETER(ResourceList);
UNREFERENCED_PARAMETER(ResourceListTranslated);

queue = WdfDeviceGetIOQueue(Device);
queueContext = QueueGetContext(queue);

WDF_DMA_ENABLER_CONFIG_INIT(&dmaConfig, WdfDmaProfileScatterGather64, DMA_BUFFER_SIZE);
status = WdfDmaEnablerCreate(Device, &dmaConfig, WDF_NO_OBJECT_ATTRIBUTES, &queueContext->DmaEnabler);
if (!NT_SUCCESS(status)) {
return status;
}

return status;
}

NTSTATUS QueueInitialize(WDFDEVICE Device) {
NTSTATUS status;
WDFQUEUE queue;
WDF_IO_QUEUE_CONFIG queueConfig;
PQUEUE_CONTEXT queueContext;

WDF_IO_QUEUE_CONFIG_INIT_DEFAULT_QUEUE(&queueConfig, WdfIoQueueDispatchSequential);
queueConfig.EvtIoRead = EvtIoRead;

WDF_OBJECT_ATTRIBUTES attributes;
WDF_OBJECT_ATTRIBUTES_INIT_CONTEXT_TYPE(&attributes, QUEUE_CONTEXT);

status = WdfIoQueueCreate(Device, &queueConfig, &attributes, &queue);
if (!NT_SUCCESS(status)) {
return status;
}

queueContext = QueueGetContext(queue);
queueContext->Queue = queue;

return status;
}
```

4. 实现DMA读取操作：

```c
VOID EvtIoRead(WDFQUEUE Queue, WDFREQUEST Request, size_t Length) {
NTSTATUS status;
PQUEUE_CONTEXT queueContext;
WDFMEMORY memory;
PVOID buffer;

queueContext = QueueGetContext(Queue);

status = WdfRequestRetrieveOutputMemory(Request, &memory);
if (!NT_SUCCESS(status)) {
WdfRequestComplete(Request, status);
return;
}

buffer = WdfMemoryGetBuffer(memory, NULL);

status = WdfDmaTransactionCreate(queueContext->DmaEnabler, WDF_NO_OBJECT_ATTRIBUTES, &queueContext->DmaTransaction);
if (!NT_SUCCESS(status)) {
WdfRequestComplete(Request, status);
return;
}

status = WdfDmaTransactionInitialize(queueContext->DmaTransaction, EvtProgramDma, EvtDmaCompletionRoutine, EvtDmaCompletionRoutine, Queue);
if (!NT_SUCCESS(status)) {
WdfObjectDelete(queueContext->DmaTransaction);
WdfRequestComplete(Request, status);
return;
}

status = WdfDmaTransactionExecute(queueContext->DmaTransaction, Request);
if (!NT_SUCCESS(status)) {
WdfObjectDelete(queueContext->DmaTransaction);
WdfRequestComplete(Request, status);
}
}

BOOLEAN EvtProgramDma(WDFDMATRANSACTION Transaction, WDFDEVICE Device, WDFCONTEXT Context, WDF_DMA_DIRECTION Direction, PSCATTER_GATHER_LIST SgList) {
UNREFERENCED_PARAMETER(Transaction);
UNREFERENCED_PARAMETER(Device);
UNREFERENCED_PARAMETER(Context);
UNREFERENCED_PARAMETER(Direction);

// 这里应该包含实际的DMA编程代码
// 例如，设置DMA控制器寄存器，配置源和目标地址等
// 使用 SgList 来获取物理地址信息

// 启动DMA传输
// StartDMATransfer();

return TRUE;
}

VOID EvtDmaCompletionRoutine(WDFDMATRANSACTION Transaction, WDFDEVICE Device, PVOID Context, WDF_DMA_DIRECTION Direction, DMA_COMPLETION_STATUS Status) {
WDFREQUEST request;
NTSTATUS status;

UNREFERENCED_PARAMETER(Device);
UNREFERENCED_PARAMETER(Context);
UNREFERENCED_PARAMETER(Direction);

request = WdfDmaTransactionGetRequest(Transaction);

if (Status == DmaComplete) {
status = STATUS_SUCCESS;
} else {
status = STATUS_IO_DEVICE_ERROR;
}

WdfRequestCompleteWithInformation(request, status, WdfDmaTransactionGetBytesTransferred(Transaction));
WdfObjectDelete(Transaction);
}
```

这个示例提供了一个更具体的PCIe DMA驱动实现框架。它使用了Windows Driver Frameworks (WDF)，这简化了许多驱动程序开发任务。

关键点：

1. 使用WDF的DMA API来管理DMA操作。
2. 实现了基本的读取操作，使用DMA传输数据。
3. 提供了DMA编程和完成回调函数的框架。

请注意，这个示例仍然需要根据实际的PCIe设备进行定制。你需要：

1. 实现具体的DMA控制器编程逻辑。
2. 添加适当的错误处理和资源管理。
3. 可能需要实现中断处理。
4. 根据设备的具体要求调整DMA配置。

开发PCIe DMA驱动程序是一个复杂的任务，需要深入理解硬件规范和Windows驱动程序模型。建议在实际开发中参考Microsoft的文档和示例，并进行充分的测试。

作者：爱学习的大牛123

windows