SYS/BIOS, OMAP-L138 experimenter kit, ARM9, UART2 interrupt isn't triggering

Damian Gowor

Other Parts Discussed in Thread: SYSBIOS

Hello,

I am trying to trigger UART2 interrupt in SYS/BIOS. I see in debug mode that when it receives data the IPEND bit is set to 0 and RBR/THR register receives proper data but the registered interrupt doesn't want to trigger. Do I need anything more than this code for configuring interrupt?

#include <ti/sysbios/family/arm/da830/Hwi.h>

xdc_Void myIsr(xdc_UArg arg)
{
	Hwi_beginIRQ();
	System_printf("\r\nInterrupt");
	Hwi_endIRQ();
}

int main()
{ 
	Hwi_Params hwiParams;
	Hwi_Handle myHwi;
	Error_Block eb;
	Error_init(&eb);
	Hwi_Params_init(&hwiParams);
	hwiParams.eventId = 61;

 hwiParams.enableInt = true;

	myHwi = Hwi_create(2, (ti_sysbios_interfaces_IHwi_FuncPtr)myIsr, &hwiParams, &eb);
	if (myHwi == NULL)
		System_abort("Hwi create failed");
	Hwi_enableIRQ();
 (...) //some task creation with System_flush() and task_sleep

 BIOS_start();

Of course UART2 is configured as well for triggering interrupts.

over 13 years ago

0 Sandeep Krishnaswamy over 13 years ago

TI__Expert 7290 points

Hi,

Are you using any of the BIOSPSP?

If not, please visit the link http://software-dl.ti.com/dsps/dsps_public_sw/psp/BIOSPSP/index.html to download the BIOSPSP. You can refer the UART drivers available in the PSP to get more insight on the implementation

Thanks and Regards,

Sandeep K

0 Damian Gowor over 13 years ago in reply to Sandeep Krishnaswamy

Expert 1110 points

Hello Sandeep,

I have checked those drivers and I have found following function:

static Void uartRegisterInterrupt(Ptr                   inDevp,
                                  Uint32                hwiNumber,
                                  Uint16                evt,
                                  Uart_pspUartIsr       intIsr)
{
    static Uint32       key         = 0;
    Uart_Object        *instHandle  = NULL ;
    ECM_Attrs           ecmattrs    = ECM_ATTRS;

    assert((NULL != intIsr) && (NULL != inDevp));

    instHandle = (Uart_Object *)inDevp;

    assert(NULL != instHandle);

    key = (Uint32)_disable_interrupts();

    /*Enable the interrupt later                                              */
    ecmattrs.unmask = 0u;

    /*setup arg such that isr will get 'chan' as arg                          */
    ecmattrs.arg    = (Arg)instHandle;

    /* Plug the ISR with interrupt (event) number                             */
    ECM_dispatchPlug(evt, (ECM_Fxn)intIsr, &ecmattrs);

    /* Enabling the event                                                     */
    ECM_enableEvent(evt);

    /* Enabling the HWI_ID where corresponding ECM group is configured        */
    C64_enableIER(1 << hwiNumber);

    /* Enabling the interrupts                                                */
    _restore_interrupts(key);
}

I didn't found any information about API that it's using.

Is it compatible with SYS/BIOS as well or only with older version?

added later:

OK I have found some information about this API in

TMS320C6000 DSP/BIOS 5.x Application Programming Interface (API)

Reference Guide but I using SYS/BIOS and ARM core.

So am I doing something wrong when I am registering the

UART2 interrupt in SYS/BIOS or this is not the way? And can

I use this API to SYS/BIOS on ARM core?

0 Damian Gowor over 13 years ago in reply to Damian Gowor

Expert 1110 points

Hello,

Today I have figured out why the interrupt doesn't want to trigger.

I should pass the the interrupt number which comes from the hardware

specification to function Hwi_create instead of hwiParams.eventId.

0 Alan DeMars over 13 years ago in reply to Damian Gowor

TI__Mastermind 30830 points

You should NOT be using the Hwi_beginIRQ() and Hwi_endIRQ() APIs in your ISR handler!

These convenience APIs are provided for interrupts that do NOT use the SYS/BIOS interrupt dispatcher. All interrupts defined using Hwi.create() or Hwi_create() use the dispatcher.

Also, you should NOT invoke Hwi_enableIRQ() in main().

SYS/BIOS enables IRQs within the call to BIOS_start().

Enabling interrupts in main() prior to BIOS_start() can cause unpredictable behavior.

Alan

0 Damian Gowor over 13 years ago in reply to Alan DeMars

Expert 1110 points

Thank you for your information.

Can I ask you how is possible to create a interrupt function which doesn't use the dispatcher?

I was thinking that zero latency interrupts (with priority = 0) created by the Hwi_create aren't

using the dispatcher.

I am not using Hwi_enableIRQ() in main. This code snipped show all things that

[just-in-case] I tested for trying to make UART2 INT work.

0 Alan DeMars over 13 years ago in reply to Damian Gowor

TI__Mastermind 30830 points

Using a priority of ZERO when creating a Hwi object will map the interrupt to FIQ rather than IRQ.

FIQs are never disabled by SYS/BIOS. Consequently, these interrupts should have zero latency.

FIQs are never ENABLED by SYS/BIOS either, so that step must be performed by the user's application by invoking Hwi_enableFIQ().

Alan

0 Damian Gowor over 13 years ago in reply to Alan DeMars

Expert 1110 points

Alan,

Thanks for confirming my conjecture.

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SYS/BIOS, OMAP-L138 experimenter kit, ARM9, UART2 interrupt isn't triggering