NAND BOOT on DM6437

Q: I am unable to boot from Nand on DM6437. I have generated an AIS image and had flashed in Nand device using nand_writer utility (a CCS project provided in the same package as genAIS utility). When I reset the board, it failed to boot from Nand.

Answer:

First, make sure of the below settings:

Set JP2 jumper to NAND on the EVM, set the SW2 switches to 0011 (AEM[2..1]=001, AEAW2=1) and the SW1 switches to 11101XXX (BM[3..0]=0111, FASTBOOT=1)

Also, check the ROM code revision to ensure that the ROM is a PG1.3 device because, according to advisory 1.2.10, in the current silicon errata document, it is specified that PG1.2 does not support NAND boot.

Using PG1.3 device, which is a latest ROM version, I could boot successfully from the NAND device.

Q: The BOOTCMPLT register ERR field contents show "A" (1010). What is significance of "A" (1010)? Could not find why we are getting this error.

Answer:

The error conditions for the ROM boot loader are as follows:

typedef enum {

    ERR_UNKNOWN_COMMAND = 1,
    ERR_BAD_MAGIC_NUMBER,
    ERR_TRANSMIT_SYNC,
    ERR_BAD_CRC,
    ERR_INVALID_ADDRESS_SIZE,
    ERR_UNSUPPORTED_BOOTMODE,
    ERR_TIMEOUT_WAITING_FOR_HOST,
    ERR_TIMEOUT_I2C_BUS_BUSY,
    ERR_TIMEOUT_MCBSP_SPI_RECEIVE,
    ERR_NAND_ACCESS_TIMEOUT,
    ERR_RECEPTION_ERR,       
    ERR_BAD_FUNCTION_PTR,
    ERR_PLL_LOCKUP,
    ERR_CFG_FUNCTION_CALL

} TISTDBOOTErrCodes;

So the error indicates that the access to the NAND device is taking too long (i.e., the device is not indicating it's readiness in a timely manner, or maybe not at all).