TMS320C6678: 关于SRIO中断设置的问题

下面是SRIO例程中设置中断的部分代码：

     /* SRIO DIO Interrupts need to be routed from the CPINTC0 to GEM Event.
     *  - We have configured DIO Interrupts to get routed to Interrupt Destination 0
     *    (Refer to the CSL_SRIO_RouteLSUInterrupts API configuration in the SRIO Initialization)
     *  - We want this System Interrupt to mapped to Host Interrupt 8 */

    /* Disable Interrupt Pacing for INTDST0 */
    CSL_SRIO_DisableInterruptPacing (hSrioCSL, 0);

    /* Route LSU0 ICR0 to INTDST0 */
    CSL_SRIO_RouteLSUInterrupts (hSrioCSL, 0, 0);

    /* Route LSU0 ICR1 to INTDST0 */
    CSL_SRIO_RouteLSUInterrupts (hSrioCSL, 1, 0);

    /* Route LSU0 ICR2 to INTDST0 */
    CSL_SRIO_RouteLSUInterrupts (hSrioCSL, 2, 0);

    /* Map the System Interrupt i.e. the Interrupt Destination 0 interrupt to the DIO ISR Handler. */
    CpIntc_dispatchPlug(CSL_INTC0_INTDST0, (CpIntc_FuncPtr)myDioTxCompletionIsr, (UArg)hSrioDrv, TRUE);

    /* The configuration is for CPINTC0. We map system interrupt 112 to Host Interrupt 8. */
    CpIntc_mapSysIntToHostInt(0, CSL_INTC0_INTDST0, 8);

    /* Enable the Host Interrupt. */
    CpIntc_enableHostInt(0, 8);

    /* Enable the System Interrupt */
    CpIntc_enableSysInt(0, CSL_INTC0_INTDST0);

    /* Get the event id associated with the host interrupt. */
    eventId = CpIntc_getEventId(8);

    /* Plug the CPINTC Dispatcher. */
    EventCombiner_dispatchPlug (eventId, CpIntc_dispatch, 8, TRUE);

然后我在sysbios中也看到一个示例代码如下：

  Int i;
  Int eventId;
  Hwi_Params hwiParams;
  Int hostInt, sysInt;
  Error_Block eb;

  // Initialize the error block
  Error_init(&eb);

  // Map 3 System interrupts (33-35) to a single Host interrupt (1).
  sysInt = 33;
  hostInt = 1;
  for (i = 0; i < 3; i++) {
       // Map System interrupts to the Host interrupt on Intc 0
       CpIntc_mapSysIntToHostInt(0, sysInt + i, hostInt);

       // Plug and enable the function and argument for System interrupts
       CpIntc_dispatchPlug(sysInt + i, myIsr, sysInt + i, TRUE);
  }

  // Enable the Host interrupt on Intc 0
  CpIntc_enableHostInt(0, hostInt);

  // Get the eventId associated with the Host interrupt
  eventId = CpIntc_getEventId(hostInt);

  // Plug the event associated with Host Interrupt.
  // The function must be 'CpIntc_dispatch' and argument 'hostInt'.
  EventCombiner_dispatchPlug(eventId, &CpIntc_dispatch, hostInt, TRUE);

  // Initialize the Hwi parameters
  Hwi_Params_init(&hwiParams);

  // The eventId must be set to the combined event
  hwiParams.eventId = (eventId / 32);

  // The arg must be set to hwiParams.eventId
  hwiParams.arg = hwiParams.eventId;

  // Enable the interrupt.
  hwiParams.enableInt = TRUE;

  // Create the Hwi on interrupt 9 then specify 'EventCombiner_dispatch'
  // as the function.
  Hwi_create(9, &EventCombiner_dispatch, &hwiParams, NULL);

针对以上代码，我有几点不明白的地方：

1、SRIO例程中的CSL_SRIO_DisableInterruptPacing (hSrioCSL, 0)这个函数的作用不太理解；

2、SRIO例程中EventCombiner_dispatchPlug (eventId, CpIntc_dispatch, 8, TRUE)这个函数的第二个参数是CpIntc_dispatch，而sysbios示例代码中这个函数的第二个参数是&CpIntc_dispatch，这是为什么呢？

3、SRIO例程中没有调用Hwi_create来映射event id到可屏蔽中断号，而sysbios示例代码中是有的，这是为什么呢？
希望专家或前辈能够解答一下，谢谢！