README.md

@@ -152,6 +152,57 @@ When using Windows, run theses steps in MSYS2.
    cmake --build . -j
    ```
 
+## Preparing and executing an OBSW update
+
+A OBSW update consists of the following two files
+
+1. Stripped OBSW binary compressed with `xz` with the name `eive-obsw.tar.xz`
+2. OBSW version text file with the name `obsw_version.txt`
+
+These files can be created manually:
+
+1. Build the release image and then switch into the build directory
+2. Run the following command: `tar -cJvf eive-obsw.tar.xz eive-obsw-stripped`
+3. Run the following command to create the version file
+
+   ```sh
+   git describe --tags --always --exclude docker_* > obsw_version.txt
+   ```
+
+You can also use the helper script `prepare-obsw-update.sh` inside the build folder
+after sourcing the `q7s-env.sh` helper script to perform all three steps.
+
+After creating these files, they need to be transferred onto the Q7S
+to either the `/mnt/sd0/bin` or to the `/mnt/sd1/bin` folder depending on which
+SD card is used.
+
+After both files are in place (this is checked by the OBSW), the example command
+sequence is used by the OBSW to write the OBSW update to the QSPI chip 0 and
+slot 0 using SD card 0:
+
+```sh
+tar -xJvf eive-obsw.tar.xz
+cp-to-other-slots.sh 0 0 /mnt/sd0/bin/eive-obsw-stripped /usr/bin/eive-obsw --np
+cp-to-other-slots.sh 0 0 /mnt/sd0/bin/obsw_update.txt /usr/share/obsw_update.txt
+```
+
+The helper script `cp-to-other-slots.sh` performs the following steps:
+
+1. It mounts the target chip and copy combination into the `/tmp` folder
+   using the `xsc_mount_copy` utility. This also unlocks the
+   writeprotection for the chip. The mount point name inside `/tmp` depends
+   on which chip and copy is used
+
+   - Chip 0 Copy 0: `/tmp/mntupdate-xdi-qspi0-nom-rootfs`
+   - Chip 0 Copy 1: `/tmp/mntupdate-xdi-qspi0-gold-rootfs`
+   - Slot 0 Copy 0: `/tmp/mntupdate-xdi-qspi1-nom-rootfs`
+   - Slot 0 Copy 0: `/tmp/mntupdate-xdi-qspi1-gold-rootfs`
+2. It writes the file with a regular `cp <source> <target>` command
+3. It enables the writeprotection using the `writeprotect` utility.
+
+This script also has an additional `--np` arguments to disable the
+re-application of write-protection after the mount and copy operation.
+
 ## Build for the Q7S target root filesystem with `yocto`
 
 The EIVE root filesystem will contain the EIVE OBSW and the Watchdog component.

scripts/compress-obsw.sh

@@ -0,0 +1,9 @@
+#!/bin/bash
+
+if [ -d eive-obsw-stripped ]; then
+	echo "No file eive-obsw-stripped found. Please ensure you are in the build folder"
+fi
+
+cmd="tar -cJvf eive-obsw.tar.xz eive-obsw-stripped"
+echo "Running command ${cmd} to generate compressed OBSW"
+eval ${cmd}

scripts/prepare-obsw-update.sh

@@ -0,0 +1,3 @@
+#!/bin/bash
+source create-version-file.sh
+source compress-obsw.sh