OMAP-L138: EDMA Chaining issue in OMAP

Hi,

In OMAP, Now I have disabled the chaining processes.

Now there is only one EDMA event ( ping pong ) which is synchronous with a 256 kHz input clock to GPIO. (GPIO BANK 1 event).

In the GPIO event, the EDMA controller need to transmit a constant value through SPI.

Even now, alternate SPI transfers are not happening.

I have increased the synchronous signal clock frequency to 445 KHz, and now its working. Below that frequency, SPI transfers are missing in alternate events. But its working perfectly at frequencies above 445 kHz. What could be the issue.

I am attaching the parameter set below, The EDMA event is enabled on channel 7 (GPIO BANK1)

    EDMA3CCPaRAMEntry paramSet;
    p = (unsigned char *)&paramSet;
    i = 0;

    /* Clean-up the contents of structure variable. */
    for (i = 0; i < sizeof(paramSet); i++)
    {
        p[i] = 0;
    }
    paramSet.srcAddr = (unsigned int) &dummy_val11;


    paramSet.destAddr = (unsigned int) (SOC_SPI_1_REGS + SPI_SPIDAT1);;

    /* aCnt holds the number of bytes in an array. */
    paramSet.aCnt = (unsigned short) 1;

    /* bCnt holds the number of such arrays to be transferred. */
    paramSet.bCnt = (unsigned short) 1;

    /* cCnt holds the number of frames of aCnt*bBcnt bytes to be transferred. */
    paramSet.cCnt = (unsigned short) 1;

    /*
     ** The srcBidx should be incremented by aCnt number of bytes since the
     ** source used here is  memory.
     */
    paramSet.srcBIdx = (short) 0;

    paramSet.destBIdx =(short)0;

    /* A sync Transfer Mode is set in OPT.*/
    /* srCIdx and destCIdx set to zero since ASYNC Mode is used. */
    paramSet.srcCIdx = (short) 0;

    /* Linking transfers in EDMA3 are not used. */

    paramSet.linkAddr = (unsigned short)0x4100;
    paramSet.bCntReload = (unsigned short)0;

    paramSet.opt = 0x00000000;

    /* Set TCC field in OPT with the tccNum. */
    paramSet.opt |= ((22 << EDMA3CC_OPT_TCC_SHIFT) & EDMA3CC_OPT_TCC);


    paramSet.opt |= EDMA3CC_OPT_TCINTEN;

    EDMA3SetPaRAM(SOC_EDMA30CC_0_REGS, 9, &paramSet);


    EDMA3CCPaRAMEntry paramSet1;
    p = (unsigned char *)&paramSet1;


    /* Clean-up the contents of structure variable. */
    for (i = 0; i < sizeof(paramSet1); i++)
    {
        p[i] = 0;
    }
    paramSet1.srcAddr = (unsigned int) &dummy_val21;


    paramSet1.destAddr = (unsigned int) (SOC_SPI_1_REGS + SPI_SPIDAT1);;

    /* aCnt holds the number of bytes in an array. */
    paramSet1.aCnt = (unsigned short) 1;

    /* bCnt holds the number of such arrays to be transferred. */
    paramSet1.bCnt = (unsigned short) 1;

    /* cCnt holds the number of frames of aCnt*bBcnt bytes to be transferred. */
    paramSet1.cCnt = (unsigned short)1;

    /*
     ** The srcBidx should be incremented by aCnt number of bytes since the
     ** source used here is  memory.
     */
    paramSet1.srcBIdx = (short) 0;
    paramSet1.destBIdx =(short)0;

    /* A sync Transfer Mode is set in OPT.*/
    /* srCIdx and destCIdx set to zero since ASYNC Mode is used. */
    paramSet1.srcCIdx = (short) 0;

    /* Linking transfers in EDMA3 are not used. */

    paramSet1.linkAddr = (unsigned short)0x4120;

    paramSet1.bCntReload = (unsigned short)0;

    paramSet1.opt = 0x00000000;


    /* Set TCC field in OPT with the tccNum. */
    paramSet1.opt |= ((22 << EDMA3CC_OPT_TCC_SHIFT) & EDMA3CC_OPT_TCC);
    paramSet1.opt |= EDMA3CC_OPT_TCINTEN;

    EDMA3SetPaRAM(SOC_EDMA30CC_0_REGS, 8, &paramSet1);

    EDMA3SetPaRAM(SOC_EDMA30CC_0_REGS, 7, &paramSet1);
}

Thank you in advance for any help you can provide.

Thank You  Sahin Okur,

Thanks for the information.