CC3100 Fs Module causes DMA Error within TI-RTOS

Hi Glenn,

This error occurs when a DMA transfer is set to read/write flash memory on Tiva devices.  Unfortunately, the DMA cannot access flash and this error is received when we try to do so.  It is likely that the compiler is placing one of your function parameters in flash.  Can you verify that all parameters used in the sl_FsOpen call are either defined in the local scope of where the function is being called or as non-const global variables?

Thanks,

-- Emmanuel

Hi Emmanuel,

Yes, I made sure that all variables are in local scope, all except the Macro FS_MODE_OPEN_WRITE.

I have simplified the code, by just asking for a file to open, which should return a negative number if the file does not exist. I still get the same DMA error. See code below.

 retVal = sl_FsOpen(slfilename, FS_MODE_OPEN_WRITE, &Token, &fileHandle);

Thanks for your assistance.

Glenn.

Hi Glenn,

What version of TI-RTOS for TivaC are you using?

I was not able to reproduce the problem on TI-RTOS 2.0.2.36.  Can you add the function below to the beginning EK_TM4C123GXL_errorDMAHwi function?

       int i;

       for (i = 0; i < 32; i++) {
              if ((int)EK_TM4C123GXL_DMAControlTable[i].pvSrcEndAddr < 0x20000000) {
                     System_printf("DMA channel %d source address is 0x%x\n", i,
                           EK_TM4C123GXL_DMAControlTable[i].pvSrcEndAddr);
              }
              if ((int)EK_TM4C123GXL_DMAControlTable[i].pvDstEndAddr < 0x20000000) {
                     System_printf("DMA channel %d source address is 0x%x\n", i,
                           EK_TM4C123GXL_DMAControlTable[i].pvDstEndAddr);

              }
       }

This function will print the flash addresses that the DMA tried to access.  You can then use the Memory Browser to see the data.  

Finally, would it be possible to post your code.

-- Emmanuel

Hi Emmanuel,

Thanks for your assistance.

I am using the same version of TI-RTOS 2.0.2.36

This is the output from the code you provided...address is 0x0

0
DMA channel 25 source address is 0x0
DMA channel 26 source address is 0x0
DMA channel 26 source address is 0x0
DMA channel 27 source address is 0x0
DMA channel 27 source address is 0x0
DMA channel 28 source address is 0x0
DMA channel 28 source address is 0x0
DMA channel 29 source address is 0x0
DMA channel 29 source address is 0x0
DMA channel 30 source address is 0x0
DMA channel 30 source address is 0x0
DMA channel 31 source address is 0x0
DMA channel 31 source address is 0x0
DMA error code: 1
DMA error!!

__ASM__, addressClock, callbackHwi, colorsPtr, currButton, dataLength, g_ulTimerInts, prevButton, processedRawData, ti_sysbios_family_arm_m3_Hwi_resetVectors, xdc_runtime_Text_charTab__A
20004880 0000A119 0000BF89 0000BF89 0000BF89
0000BF89 0000BF89 0000BF89 0000BF89 0000BF89
0000BF89 0000BF89 0000BF89 0000BF89 0000BC39

Here is the code

// Globals
#define SL_FILE_NAME    "MacDonalds.txt"
#define BUF_SIZE        2048

#define SIZE_64K        65536

union
{
    UINT8 g_Buf[BUF_SIZE];
    UINT32 demobuf[BUF_SIZE/4];
} uNvmemBuf;

const UINT8    oldMacDonald[] = "Old MacDonald had a farm,E-I-E-I-O, \
        And on his farm he had a cow, \
        E-I-E-I-O, \
:
        E-I-E-I-O.";

// Function
int updateConfig()
{
    INT32         fileHandle = -1;

    UINT32        Token = 0;
    UINT16        loop = 0;
    INT32         retVal = 0;


    unsigned char * slfilename = "config.txt";

    /* open a user file for writing */
    //retVal = sl_FsOpen((unsigned char *)SL_FILE_NAME, FS_MODE_OPEN_WRITE, &Token, &fileHandle);
    retVal = sl_FsOpen(slfilename, FS_MODE_OPEN_WRITE, &Token, &fileHandle);  <-- CRASHES HERE

    if(retVal < 0)
    {
:
    return 0;
}


Void echoFxn(UArg arg0, UArg arg1)
{
    WiFi_Handle       handle;
    WiFi_Params       wifiParams;
    _NetCfgIpV4Args_t ipV4;
    uint8_t           len = sizeof(ipV4);
    uint8_t           dhcpIsOn;
    int               nbytes;
    int               status;
    int               selectRes;
    int               slSocket;
    fd_set            readSet;
    timeval           timeout;
    sockaddr_in       localAddr;
    sockaddr_in       client_addr;
    socklen_t         addrlen = sizeof(client_addr);
    int 		      processStatus;
    int				  configValue;

    ULong       currButton;
    ULong		deleteButton;
    ULong       prevButton = 0;

    /* Turn LED OFF. It will be used as a connection indicator */
    GPIO_write(Board_LED0, Board_LED_OFF); //Blue
    GPIO_write(Board_LED1, Board_LED_OFF); //Green
    GPIO_write(Board_LED2, Board_LED_OFF); //Red

    /* Open WiFi driver */
    WiFi_Params_init(&wifiParams);
    wifiParams.bitRate = SPI_BIT_RATE;
    handle = WiFi_open(Board_WIFI, Board_SPI_CC3100, NULL, &wifiParams);
    if (handle == NULL) {
        System_abort("WiFi driver failed to open.");
    }


    /*
     * Host driver starts the network processor.
     *
     * sl_Start returns the network processor operating mode:
     *      ROLE_STA (0x00): configured as a station
     *      ROLE_AP  (0x02): configured as an access point
     */

    configValue = sl_Start(NULL, NULL, NULL);
    if (configValue < 0) {
        System_abort("Could not initialize WiFi");
    }


    // Holding down button switches the connection mode
    deleteButton = GPIO_read(Board_BUTTON1);
    if(deleteButton == 0) //&& (prevButton != 0))
    {
    	    if (configValue == ROLE_STA) {

       	        /* Change mode to access point */
        	    configValue = sl_WlanSetMode(ROLE_AP);

    	        // Set SSID name for AP mode
    	        unsigned char  str[33] = "LightServerAP";
    	        unsigned short  length = strlen((const char *)str);
    	        sl_WlanSet(SL_WLAN_CFG_AP_ID, WLAN_AP_OPT_SSID, length, str);

    	        // Set security type for AP mode
    	        //Security options are:
    	        //Open security: SL_SEC_TYPE_OPEN
    	        //WEP security:  SL_SEC_TYPE_WEP
    	        //WPA security:  SL_SEC_TYPE_WPA
    	        unsigned char  val = SL_SEC_TYPE_OPEN;
    	        sl_WlanSet(SL_WLAN_CFG_AP_ID, WLAN_AP_OPT_SECURITY_TYPE, 1, (unsigned char *)&val);

    	        //Set Password for for AP mode (for WEP or for WPA) example:
    	        //Password - for WPA: 8 - 63 characters
    	        //           for WEP: 5 / 13 characters (ascii)
    	        //unsigned char  str[65];
    	        //unsigned short  len = strlen(password);
    	        //memset(str, 0, 65);
    	        //memcpy(str, password, len);
    	        //sl_WlanSet(SL_WLAN_CFG_AP_ID, WLAN_AP_OPT_PASSWORD, len, (unsigned char *)str);

    	        /* Restart the network processor */
    	        configValue = sl_Stop(0);
    	        configValue = sl_Start(NULL, NULL, NULL);
    	    }
    	    else if  (configValue == ROLE_AP) {
    	        /* Change mode to wireless station */
    	        configValue = sl_WlanSetMode(ROLE_STA);

    	        /* Restart the network processor */
    	        configValue = sl_Stop(0);
    	        configValue = sl_Start(NULL, NULL, NULL);
    	    }
    }


    // We are in Station Mode, so need to connect to Wifi Router/Access Point
    if (configValue == ROLE_STA)
    {
        // Turn LED to Red to indicate that device is attempting to connected to Wifi Router
        GPIO_write(Board_LED0, Board_LED_OFF); //Blue
        GPIO_write(Board_LED1, Board_LED_OFF); //Green
        GPIO_write(Board_LED2, Board_LED_ON); //Red

		/*
		 * Wait for the WiFi to connect to an AP. If a profile for the AP in
		 * use has not been stored yet, press Board_BUTTON0 to start SmartConfig.
		 */
		while ((deviceConnected != true) || (ipAcquired != true)) {
			/*
			 *  Start SmartConfig if a button is pressed. This could be done with
			 *  GPIO interrupts, but for simplicity polling is used to check the
			 *  button.
			 */

			currButton = GPIO_read(Board_BUTTON1);
			if((currButton == 0) && (prevButton != 0))
			{
				smartConfigFxn();
			}
			prevButton = currButton;
			Task_sleep(50);
		}
    }

    // Set the color of LED to indicate which mode we are in
    if (configValue == ROLE_STA)
    {
        // Turn LED to Blue to indicate that device is connected in Station Mode
        GPIO_write(Board_LED0, Board_LED_ON); //Blue
        GPIO_write(Board_LED1, Board_LED_OFF); //Green
        GPIO_write(Board_LED2, Board_LED_OFF); //Red
    }
    else
    {
        // Turn LED to Green to indicate that device is in AP mode
        GPIO_write(Board_LED0, Board_LED_OFF); //Blue
        GPIO_write(Board_LED1, Board_LED_ON); //Green
        GPIO_write(Board_LED2, Board_LED_OFF); //Red
    }

    /* Print IP address */
    sl_NetCfgGet(SL_IPV4_STA_P2P_CL_GET_INFO, &dhcpIsOn, &len,
                 (unsigned char *)&ipV4);
    System_printf("CC3100 has connected to an AP and acquired an IP address.\n");
    System_printf("IP Address: %d.", SL_IPV4_BYTE(ipV4.ipV4, 3));
    System_printf("%d.", SL_IPV4_BYTE(ipV4.ipV4, 2));
    System_printf("%d.", SL_IPV4_BYTE(ipV4.ipV4, 1));
    System_printf("%d", SL_IPV4_BYTE(ipV4.ipV4, 0));
    System_printf("\n");
    System_flush();

    /* Create a UDP socket */
    slSocket = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
    if (slSocket < 0) {
        System_printf("Error: socket not created.");
        WiFi_close(handle);
        Task_exit();
    }

    memset((char *)&localAddr, 0, sizeof(localAddr));
    localAddr.sin_family = AF_INET;
    localAddr.sin_addr.s_addr = htonl(0);
    localAddr.sin_port = htons(UDPPORT);
    status = bind(slSocket, (const sockaddr *)&localAddr, sizeof(localAddr));
    if (status < 0) {
        System_printf("Error: bind failed.");
        close(slSocket);
        WiFi_close(handle);
        Task_exit();
    }

    SysCtlClockSet(SYSCTL_SYSDIV_1 | SYSCTL_USE_OSC | SYSCTL_OSC_MAIN | SYSCTL_XTAL_16MHZ);
    SSIConfigSetExpClk(SSI0_BASE, SysCtlClockGet(), SSI_FRF_MOTO_MODE_1, SSI_MODE_MASTER, 1000000, 16);

    // Enable the SPI SSI0 module.
    SSIEnable(SSI0_BASE);

   //////////////////
   updateConfig();    <--CALLS THE FUNCTION
   /////////////////

Glenn

I just realised that it is not printing out all the DMA channels, and suspected this was due to the System_print buffer running out of space. Hence I added System_flush() so everything would print out.

Here is the updated debug code

	int i;

	for (i = 0; i < 32; i++) {
	       if ((int)EK_TM4C123GXL_DMAControlTable[i].pvSrcEndAddr < 0x20000000) {
	              System_printf("DMA channel %d source address is 0x%x\n", i,
	                    EK_TM4C123GXL_DMAControlTable[i].pvSrcEndAddr);
	              System_flush();
	       }
	       if ((int)EK_TM4C123GXL_DMAControlTable[i].pvDstEndAddr < 0x20000000) {
	              System_printf("DMA channel %d source address is 0x%x\n", i,
	                    EK_TM4C123GXL_DMAControlTable[i].pvDstEndAddr);
	              System_flush();
	       }
	}

Here is the output now - have a look at DMA channel 13 and DMA12 seems to be missing

DMA channel 0 source address is 0x0
DMA channel 0 source address is 0x0
DMA channel 1 source address is 0x0
DMA channel 1 source address is 0x0
DMA channel 2 source address is 0x0
DMA channel 2 source address is 0x0
DMA channel 3 source address is 0x0
DMA channel 3 source address is 0x0
DMA channel 4 source address is 0x0
DMA channel 4 source address is 0x0
DMA channel 5 source address is 0x0
DMA channel 5 source address is 0x0
DMA channel 6 source address is 0x0
DMA channel 6 source address is 0x0
DMA channel 7 source address is 0x0
DMA channel 7 source address is 0x0
DMA channel 8 source address is 0x0
DMA channel 8 source address is 0x0
DMA channel 9 source address is 0x0
DMA channel 9 source address is 0x0
DMA channel 10 source address is 0x0
DMA channel 10 source address is 0x0
DMA channel 11 source address is 0x0
DMA channel 11 source address is 0x0
DMA channel 13 source address is 0x3d87
DMA channel 14 source address is 0x0
DMA channel 14 source address is 0x0
DMA channel 15 source address is 0x0
DMA channel 15 source address is 0x0
DMA channel 16 source address is 0x0
DMA channel 16 source address is 0x0
DMA channel 17 source address is 0x0
DMA channel 17 source address is 0x0
DMA channel 18 source address is 0x0
DMA channel 18 source address is 0x0
DMA channel 19 source address is 0x0
DMA channel 19 source address is 0x0
DMA channel 20 source address is 0x0
DMA channel 20 source address is 0x0
DMA channel 21 source address is 0x0
DMA channel 21 source address is 0x0
DMA channel 22 source address is 0x0
DMA channel 22 source address is 0x0
DMA channel 23 source address is 0x0
DMA channel 23 source address is 0x0
DMA channel 24 source address is 0x0
DMA channel 24 source address is 0x0
DMA channel 25 source address is 0x0
DMA channel 25 source address is 0x0
DMA channel 26 source address is 0x0
DMA channel 26 source address is 0x0
DMA channel 27 source address is 0x0
DMA channel 27 source address is 0x0
DMA channel 28 source address is 0x0
DMA channel 28 source address is 0x0
DMA channel 29 source address is 0x0
DMA channel 29 source address is 0x0
DMA channel 30 source address is 0x0
DMA channel 30 source address is 0x0
DMA channel 31 source address is 0x0
DMA channel 31 source address is 0x0
DMA error code: 1
DMA error!!

This what is at DMA13 address

$C$SL13
666E6F63 742E6769
C0007478

Glenn.

Emmanuel,

Thank you very much, this resolved the issue!

Just a note to others, this is slightly different to the actual sample code provided with the CC3100 SDK. You need to specifically point to the location &fileName

Glenn.

Addressed to TI folks, I suppose:  The sample code in the CC3100/3200 .... User's Guide has this use of constant strings.  Cut and paste TI sample code, compile it, and run it, and the DMA blows a gasket on the flash.  The documents and any other sample code should be amended, and this issue highlighted.

I wasted some time on this problem; of course I don't mind the fact that the system works that way - it's normal - but I do mind that TI's samples blow up.