Difference between revisions of "WISE-PaaS/OTA Agent(risc linux)"
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The persistent data partition stores data that needs to be preserved through an update.For our rsb4220, the partition layout is as follow: | The persistent data partition stores data that needs to be preserved through an update.For our rsb4220, the partition layout is as follow: | ||
+ | |||
+ | */dev/mmcblk0p1 containing the u-boot | ||
+ | */dev/mmcblk0p2 containing the Current System, or named the active partition | ||
+ | */dev/mmcblk0p3 before update, it is blank, it will be used by the update mechanism to write the updated image | ||
+ | */dev/mmcblk0p4 persistent data | ||
[[File:Linux-ota.png|RTENOTITLE]] | [[File:Linux-ota.png|RTENOTITLE]] |
Revision as of 10:40, 4 November 2016
Contents
Introduction
This document demonstrates how to support our ota-agent solution under your risc arm linux.
Requirement
- The storage(sd card, Nand flash) capacity need greate than 4G. 8G is recommended
Note
We take our rsb4220 (TI am335x platform) for example. For other platform, it is similar
Architecture
In order to support rollback, we requires the device to have a certain partition layout. At least four different partitions are needed:
- one boot partition, containing the U-Boot bootloader and its environment
- two partitions for storing the root file system and kernel. The kernel image file, zImage, and any device tree binary should be stored in directory /boot
- one for persistent data
One of the rootfs and kernel partitions will be marked as the active partition, from which the kernel and rootfs will be booted. The other, called the inactive partition, will be used by the update mechanism to write the updated image. After an update their roles are swapped.
The persistent data partition stores data that needs to be preserved through an update.For our rsb4220, the partition layout is as follow:
- /dev/mmcblk0p1 containing the u-boot
- /dev/mmcblk0p2 containing the Current System, or named the active partition
- /dev/mmcblk0p3 before update, it is blank, it will be used by the update mechanism to write the updated image
- /dev/mmcblk0p4 persistent data