This repo creates the Linux firmware images for the Open Trickler project.
The following files and directories are the most relevant for Open Trickler:
configs/opentrickler_dev_defconfigconfigs/opentrickler_prod_defconfigpackage/python-opentrickler/board/ammolytics/opentrickler/
make opentrickler_dev_defconfig
make
The resulting firmware images will be in output/images/.
Always keep commits to the opentrickler-2022.05.x on top of the latest upstream 2022.05.x branch.
git checkout 2022.05.x
git pull
git checkout opentrickler-2022.05.x
git merge 2022.05.x
git push origin opentrickler-2022.05.x
First, use fdisk to list the partitions and block positions.
fdisk -l output/images/sdcard.img
Example output
Disk output/images/sdcard.img: 596 MiB, 624951808 bytes, 1220609 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x00000000
Device Boot Start End Sectors Size Id Type
output/images/sdcard.img1 * 1 65536 65536 32M c W95 FAT32 (LBA)
output/images/sdcard.img2 65537 1089536 1024000 500M 83 Linux
output/images/sdcard.img3 1089537 1220608 131072 64M c W95 FAT32 (LBA)
The math that determines the block offset needed to mount a parition
start * sector size = offset # equation
1 * 512 = 512 # BOOT parition
65537 * 512 = 33554944 # Linux root partition
1089537 * 512 = 557842944 # CODE parition
Mounting the paritions (read-only)
sudo mkdir /mnt/ot-img/boot /mnt/ot-img/rootfs /mnt/ot-img/code
sudo mount -o loop,ro,sync,offset=512 output/images/sdcard.img /mnt/ot-img/boot
sudo mount -o loop,ro,offset=33554944 -t ext4 output/images/sdcard.img /mnt/ot-img/rootfs
sudo mount -o loop,ro,sync,offset=557842944 output/images/sdcard.img /mnt/ot-img/code
Unmount the paritions
sudo umount /mnt/ot-img/boot
sudo umount /mnt/ot-img/rootfs
sudo umount /mnt/ot-img/code