EBLINUX-26196: Update initrd-generator docs

docs/images/params.md

@@ -86,10 +86,11 @@ a meta-package for the kernel binary and modules.
 
 - **packages** _(boot/initrd/root/config)_  \[default: None \]: A list of packages.
 For the _root generator_, these packages are installed in the base _deboostrap_ environment.
-For the _initrd generator_, these packages will be downloaded and extracted to get the kernel modules.
+For the _initrd generator_, these packages will be downloaded, extracted and integrated into the resutling _initrd.img_.
 For the _boot generator_, these packages will be downloaded and extracted to get the kernel binary.
 
 - **kernel** _(boot/initrd/root)_  \[default: None \]: Name of the kernel package.
+For the _initrd generator_, these packages will be downloaded and extracted to a temporary folder to get the required kernel modules.
 
 - **tar** _(boot)_  \[default: True \]: Flag for packing the boot artifacts as a tarball.
 If _embdgen_ is used to write the artifacts to an image, this will preserve the owner and mode of the artifacts.

docs/tools/initrd.md

@@ -15,11 +15,12 @@ The internal steps are:
 
  1. Read in YAML configuration file
  2. Add BusyBox binary
- 3. Add kernel modules, extracts the specified modules
- 4. Creates device nodes for initrd image based on the configuration.
- 5. Copy all specified files and directories into the initrd image
- 6. Generates init script
- 7. Generate initrd based on all the files with `cpio`
+ 3. Download and extract additional packages
+ 4. Add kernel modules, extracts the specified modules
+ 5. Creates device nodes for initrd image based on the configuration.
+ 6. Copy all specified files and directories into the initrd image
+ 7. Generate the init script
+ 8. Generate initrd based on all the files using `cpio`
 
 ## Configuration options
 
@@ -53,4 +54,8 @@ devices:
     major: <major_number>
     minor: <minor_number>
   - ...
+# Packages to add, e.g. e2fstools
+packages:
+  - <package name>
+  - ...
 ```