DM6446 Rev. G. DDR2 part number

You may have to run this past the Spectrum Digital folks through their help desk, I am not sure what particular part they are replacing the old Micron DDR with. I can say that in general any JEDEC compliant DDR2 device should do fine, you do not necessarily need to use the same DDR chips.

Thank you for the answer,

Actually we choose a DDR2 device with a clock rate of 333MHz (not 267MHz) and would like to learn whether we have to patch any source or not and what they are. (Ubl, Uboot, Uimage etc.)

Regards,

Ferhat

Keep in mind that just because you are using a higher grade DDR2 device does not mean that the DDR2 interface on the DM6446 can handle the additional speed, the DDR2 interface on the DM6446 can only operate up to a maximum of 166MHz (i.e. 6ns) clock as per the datasheet, so your DDR2 bus frequency will likely not be changing.

However if your new DDR2 device does require some different settings aside from clock than you would need to modify some sources, though if it is the same size and same manufacturer than chances are the configuration you have will work (DDR2 is generally backwards compatible from a timing perspective). If you do need to change things the two main places would be UBL and U-Boot, at a minimum UBL configures the DDR2 controller so U-Boot can run, and I believe U-Boot will also be configuring the DDR2 again as it has the capability to run directly from NOR. I do not believe you need to modify the kernel itself (uImage) with the DDR2 configuration changes as I believe it is all handled in the boot loaders.

Thanks Bernie,

I found two tools to flash the TMS320DM6446 using serial port.

First is DVFlasher_1_10.exe which has been depracated. (includes sources for ubl and binary file for u-boot)

Second is  sfh_DM644x.exe. (includes sources for ubl but no binary for u-boot)

I can flash the EVM from NAND using ubl_DM6446_NAND.bin and u-boot-567-nand.bin. Although the sources of ubl_DM6446_NAND.bin is included in the project, there is no source or binary for "U-BOOT" (I found it from Spectrum Digitals site).

How can I find the sources for "U-BOOT"? Or do I need it for NAND boot? We will end up with TMS320DM6441 so can we use same "U-BOOT" binary for TMS320DM6441?

Thanks and best regards,

Ferhat

Hi,

Thanks for your reply.

I found the u-boot-1.2.0.tgz  in  /home/ferhat_olgun/dvsdk_1_30_01_41/ PSP_01_20_00_014/board_utilities.  Then I could succesfully:

-compile it for NAND flash

-send both ubl_DM6446_NAND.bin and u-boot-1.2.0-davinci.bin to EVM

-set&save environment variables

-get uImage from TFTP and mount NFS filesys

However with the u-boot-1.2.0-davinci.bin  the environment variables always be cleared on each power on. Below is the initial log for each start:

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

DM6446 initialization passed!
Booting TI User Boot Loader
        UBL Version: 1.65
        UBL Flashtype: NAND
Starting NAND Copy...
Valid magicnum, 0x55424CBB, found in block 0x00000006.
   DONE
Jumping to entry point at 0x81080000.

U-Boot 1.2.0 (Mar 24 2010 - 20:03:33)

DRAM:  256 MB
unknown vendor=0 Flash:  0 kB
NAND:  NAND device: Manufacturer ID: 0xec, Chip ID: 0x36 (Samsung NAND 64MiB 1,8V 8-bit)
64 MiB
*** Warning - bad CRC or NAND, using default environment

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

How could I write env. variables to NAND permanently? What may be the problem?

Regards

Ferhat OLGUN said:

How could I write env. variables to NAND permanently? What may be the problem?

U-Boot should be writing the variables to NAND when you run saveenv, do you get any warnings or errors when you run the saveenv command?

Since you can get U-Boot and UBL to run out of NAND you must be able to write to it at some point, are you ever able to write anything to NAND from U-Boot (like writing a new U-Boot image from U-boot)?

My first guess would be that if you were using some different flash from the EVM that it requires some different write sequences or timing that may have to be adjusted in your U-Boot sources, however since you wrote to the NAND already somehow, I am not sure why that would happen.

Thanks Bernie,

First of all, I tried all in DM6446EVM and will try them on our custom design soon.

I could saveenv the variables and start kernel image with the "u-boot-567-nand.bin" which I have downloaded from Spectrum Digital's site.

With "u-boot-1.2.0-davinci.bin" , saveenv does not give any warnings and errors and can start kernel image without any problem. However in each startup variables change to default.

I have not tried writing anything to NAND from U-boot (like new U-boot) yet but I will try to see if I could write.

Thanks again,

Ferhat