How can I get the uboot off an SD card and then put it on another? dd is fine, but how much do I move?
The whole 4MB infront of the first partition? Or is there some way to determine the actual uboot size and grab just that?
thanks
Hi
Am 01.03.22 um 05:45 schrieb Robert Moskowitz:
How can I get the uboot off an SD card and then put it on another? dd is fine, but how much do I move?
everything between sector #0 and the first sector of the first partition (mostly something between 2048 and 8192 for non-android firmware, fdisk -l /dev/mmcblk[01] will tell you how much). Keep in mind that the MBR partition table resides at the end of the first sector, so you may want to skip this section when burning the firmware to a different card, see here: https://github.com/umiddelb/z2d/blob/master/odroid-c2/ubuntu-base-00.sh#L10-... .
The whole 4MB infront of the first partition? Or is there some way to determine the actual uboot size and grab just that?
In the past, there was no common / canonical way, see here: https://github.com/umiddelb/armhf/wiki/Get-more-out-of-%22Das-U-Boot%22#disk...
Cheers Uli
You can safely copy the U-Boot section from one SD card to another using the dd command. Typically, U-Boot is stored within the first few megabytes before the first partition, so cloning the first 4MB is usually enough. You can do this by running sudo dd if=/dev/sdX of=uboot.img bs=1M count=4 and then sudo dd if=uboot.img of=/dev/sdY bs=1M count=4, replacing sdX and sdY carparkingmultiiapk.com with your actual device names. This method ensures you capture the full bootloader region. If you want to be more precise, refer to your board’s documentation for the exact offset and size of the U-Boot image.