Zedboard: Enable PL Interrupt in FreeRTOS

Question

Hi,

I'm quite new to Application Development for Zynq Chips.

I successfully implemented a PL->PS interrupt in a baremetal environment using the tutorials. Now I thought porting it to FreeRTOS would be straight forward but once the task scheduler runs I can't get any interrupt fired.

I'm sure I'll just have to link my ISR to some FreeRTOS Task/function but can't find any hints on how to do so. I would really appreciate it if someone could point me in the right direction.

Edit: I'm using an AXI GPIO Core connected to the push buttons with F2PIRQ. The GPIO is initialized using the XGpio_* functions.

My initializing code is the following (called from main, as any call from a task will crash the system):

int SetupInterruptSystem()
{
   int Result;
   INTC *IntcInstancePtr = &Intc;

   XScuGic_Config *IntcConfig;

   /*
   * Initialize the interrupt controller driver so that it is ready to
   * use.
   */
   IntcConfig = XScuGic_LookupConfig(INTC_DEVICE_ID);
   if (NULL == IntcConfig) {
       return XST_FAILURE;
   }

   Result = XScuGic_CfgInitialize(IntcInstancePtr, IntcConfig,
                   IntcConfig->CpuBaseAddress);
   if (Result != XST_SUCCESS) {
       return XST_FAILURE;
   }

   Xil_ExceptionRegisterHandler(XIL_EXCEPTION_ID_INT,
           (Xil_ExceptionHandler)INTC_HANDLER, IntcInstancePtr);

   /* Enable non-critical exceptions */
   Xil_ExceptionEnable();

   /*
   * Connect the interrupt handler that will be called when an
   * interrupt occurs for the device.
   */
   Result = XScuGic_Connect(IntcInstancePtr, XPAR_FABRIC_AXI_BTN_IN_IP2INTC_IRPT_INTR,
               (Xil_ExceptionHandler)GpioIsr, (void *) &Gpio);
   if (Result != XST_SUCCESS) {
       return Result;
   }

   XGpio_InterruptEnable(&Gpio, 1);
   XGpio_InterruptGlobalEnable(&Gpio);

   XScuGic_Enable(IntcInstancePtr, XPAR_FABRIC_AXI_BTN_IN_IP2INTC_IRPT_INTR);

   /*
   * Initialize the exception table and register the interrupt
   * controller handler with the exception table
   */
   //Xil_ExceptionInit();

   return XST_SUCCESS;
}

ddervaric · Accepted Answer

For future Reference if anyone else stumbles upon the problem (and can't figure it out immediately from the link Josh provided):

You need to use the global xInterruptController Instance from PortZynq7000.c. Switching this ScuGic Instance alone and copy/pasting the rest of fshenmis post didn't work for me, as I (and I don't know why exactly) had to reconfigure the XScuGic instance. The full code should look like this:

******************************************************************************************

extern XScuGic xInterruptController;
XScuGic_Config *IntcConfig;

IntcConfig = XScuGic_LookupConfig(XPAR_SCUGIC_SINGLE_DEVICE_ID);
if (NULL == IntcConfig)
{
return XST_FAILURE;
}

int xResult = XScuGic_CfgInitialize(&xInterruptController, IntcConfig, IntcConfig->CpuBaseAddress);
if(xResult != XST_SUCCESS)
{
return XST_FAILURE;
}

//Connect to the hardware
Xil_ExceptionRegisterHandler(XIL_EXCEPTION_ID_INT,(Xil_ExceptionHandler)XScuGic_InterruptHandler,&xInterruptController);

//Trigger Rising Edge
XScuGic_SetPriorityTriggerType(&xInterruptController, [PARAMETER FOR YOUR INTERRUPT (taken from xparameters.h)], 4, 3);

XScuGic_Connect(&xInterruptController, [PARAMETER FOR YOUR INTERRUPT (taken from xparameters.h)], (Xil_ExceptionHandler) [YOUR_ISR_SERVICE_ROUTINE], (void *)&[INSTANCE OF YOUR DEVICE DRIVER (e.g. Gpio etc.)]);

//Enable PL-PS INTR Pin (which is the parameter you've connected before)
XScuGic_Enable(&xInterruptController, [PARAMETER FOR YOUR INTERRUPT (taken from xparameters.h)]);

******************************************************************************************