SRIO Doorbell info 发送失败

大家好，

我在C6670上面通过SRIO发送一个Doorbell包给FPGA（Xilinx V6）。

大致的代码如下：

Srio_DrvBuffer  DBLL_Info;

/* Open DIO SRIO Non-Blocking Socket */
srioSocket= Srio_sockOpen (hSrioDrv, Srio_SocketType_DIO, FALSE);
if (srioSocket== NULL)
{
      System_printf ("Error: Unable to open the DIO socket - %d\n", 0);
      return -1;
}
// DIO Binding Information: Use 16 bit identifiers
bindInfo.dio.doorbellValid  = 0;
bindInfo.dio.intrRequest    = 1;
bindInfo.dio.supInt         = 0;
bindInfo.dio.xambs          = 0;
bindInfo.dio.priority       = 0;
bindInfo.dio.outPortID      = 3;
bindInfo.dio.idSize         = 0;
bindInfo.dio.srcIDMap       = 0;
bindInfo.dio.hopCount       = 0;
bindInfo.dio.doorbellReg    = 0;
bindInfo.dio.doorbellBit    = 0;


/* Bind the SRIO socket: DIO sockets do not need any binding information. */ 
if (Srio_sockBind_DIO (srioSocket, &bindInfo) < 0)
{
    System_printf ("Error: Binding the SIO socket failed.\n");
    return -1;
}

//设置Doorbell Info的为Reg=1，Bit=3    
*DBLL_Info = (int32_t)SRIO_SET_DBELL_INFO(1,3);

/* Populate the DIO Address Information where the data is to be sent. */
to.dio.rapidIOMSB    = 0x0;
to.dio.rapidIOLSB    = (uint32_t)READ_BASE_ADDR;	
to.dio.dstID         = 0xAA;		//FPGA;
to.dio.ttype         = dio_ttype;
to.dio.ftype         = dio_ftype;//为0xA

//发送一次Doorbell包
if (Srio_sockSend_DIO (srioSocket,DBLL_Info, 1, (Srio_SockAddrInfo*)&to) < 0)
{
   System_printf ("Debug(Core %d): DIO Socket Example Failed\n", coreNum);
   return -1;
}

按照我的理解，

if (Srio_sockSend_DIO (srioSocket,DBLL_Info, 1, (Srio_SockAddrInfo*)&to) < 0)

这句代码实现的是DSP对外发送一个Doorbell包，我在这里设置断点，每执行一次，可以在FPGA端通过Chipscope抓取到包。
观察包的内容的确是Doorbell类型的，TargetID、SourceID都正确。
但是问题是：

FPGA抓取的来自DSP的Doorbell包的DoorbellInfo始终为0x0000。虽然我在DSP程序中设置DoorbellInfo为Reg=1，Bit=3发送的。

而且我通过Memory Browser观察0x02900D14即LSU0的Reg5，也是DoorbellInfo为0x0000.

感觉就是DoorbellInfo没有设置到LSU里面。

请问这个问题应该如何解决？
谢谢了～～