Search

Technical Discussion Group Forum

This forum is provided for user discussion. While Beacon EmbeddedWorks support staff and engineers participate, Beacon EmbeddedWorks does not guarantee the accuracy of all information within in the Technical Discussion Group (TDG).

The "Articles" forums provide brief Articles written by Beacon EmbeddedWorks engineers that address the most frequently asked technical questions.

To receive email notifications when updates are posted for a Beacon EmbeddedWorks product download, please subscribe to the TDG Forum of interest.

TDG Forum

PrevPrev Go to previous topic
NextNext Go to next topic
Last Post 21 Feb 2013 02:12 PM by  mike.arensdorf
On boot from SD card LoLo launches rather than uboot.
 3 Replies
Sort:
You are not authorized to post a reply.
Author Messages
mike.arensdorf
New Member
New Member
Posts:


--
06 Feb 2013 03:40 PM
    I have a 16GB SD card that I've been using with a DM3730 Torpedo SOM. After running makeyaffsboot from uboot I've been booting from NAND flash. Occasionally I stop uboot and re-run makeyaffsboot to install a new image. No problems. Just got a new DM3730 Torpedo + Wireless SOM, and thought I could pop this same SD card into it, power up, stop uboot, change uboot environment variables (if necessary), and run makeyaffsboot. But instead of uboot, LogicLoader runs (after several seconds of no response). So I inserted the Linux Demo SD card and cycled power - uboot came up as expected. Naturally I figured my original 16GB SD card must be missing something, so I copied the files (MLO first) from the Linux Demo SD card such that the original card had exactly the same files, no more, no less. Still no joy - LogicLoader runs instead of uboot. I'm thinking now that the CPU boot ROM can't read the 16GB SD card (MLO in particular) in order to run x-loader? I thought I had booted directly from the same 16GB SD card before ever running makeyaffsboot on the original wired SOM, but I may be mistaken. Wondering if I can boot the Linux Demo SD card, stop uboot, swap to the 16GB SD card and then run makeyaffsboot(?)
    richard.laborde@logicpd.com
    Basic Member
    Basic Member
    Posts:247


    --
    11 Feb 2013 08:56 AM
    Mike,

    I'm checking internally to see if there is a size limit that would prevent the 16GB card from working. I know the largest one I have used is 4 GB.

    Can you confirm that you properly formatted the 16 GB card to boot from SD before you copied the MLO file? The formatting process is described many places to successfully boot from SD.
    Thanks
    mike.arensdorf
    New Member
    New Member
    Posts:


    --
    12 Feb 2013 08:12 AM
    OK - I found that my 16GB SD card did NOT have a boot partition. So I used mkLogicFATcard.sh to reformat this card into a bootable card, and was able to bring up uboot. However, only ~90MB of the card is available. I then repartitioned/formatted the card using the Linux Disk Utility to get a 16GB bootable (supposedly) partition, and copied the files from the Linux Demo SD card (MLO first). This card would get further in the boot sequence but x-loader errored while finding/starting uboot. So I went back to using mkLogicFATcard.sh and was able to re-create a bootable card. I then used parted to add another FAT32 partition from 91MB to 16GB - and this card was able to boot and run the demo, and the larger partition/fs is available. So this card seems useable, but I'm wondering if the scripts (mkyaffsboot) will work if the rootfs.yaffs2 is on the second/larger partition(?)
    mike.arensdorf
    New Member
    New Member
    Posts:


    --
    21 Feb 2013 02:12 PM
    Additional notes:

    I was able to modify mkLogicFATcard.sh to get a 132MiB boot-able partition:

    Near line 26, change "echo ,11,0x0C,*" to "echo ,17,0x0C,*" to specify cylinder 17 (132MiB) as the end rather than cylinder 11 (90MiB).

    Specifying more than 17 will cause the SD card to be unboot-able.

    Fortunately 132MiB is enough for my YAFFS image, so I was able to run makeyaffsboot to install the YAFFS in NAND. Once installed, the system boots from NAND (of course) so I could reformat the SD card to 16GB (no longer boot-able) and used it to install larger YAFFS images.
    You are not authorized to post a reply.