diff options
| author | Anton Ivanov | 2022-01-04 10:44:57 +0000 |
|---|---|---|
| committer | Richard Weinberger | 2022-03-11 10:43:32 +0100 |
| commit | 6427c165275fe11634862149002c7867f25d02f6 (patch) | |
| tree | 286675d491639345f0a08f9f79d617dc3c054cb1 /Documentation/virt | |
| parent | 2a6852cb8ff0c8c1363cac648d68489343813212 (diff) | |
um: Document dtb command line option
Add documentation for the dtb command line option and the
ability to load/parse device trees.
Signed-off-by: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Reviewed-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Diffstat (limited to 'Documentation/virt')
| -rw-r--r-- | Documentation/virt/uml/user_mode_linux_howto_v2.rst | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/Documentation/virt/uml/user_mode_linux_howto_v2.rst b/Documentation/virt/uml/user_mode_linux_howto_v2.rst index 2cafd3c3c6cb..81986fe014d4 100644 --- a/Documentation/virt/uml/user_mode_linux_howto_v2.rst +++ b/Documentation/virt/uml/user_mode_linux_howto_v2.rst @@ -1189,6 +1189,26 @@ E.g. ``os_close_file()`` is just a wrapper around ``close()`` which ensures that the userspace function close does not clash with similarly named function(s) in the kernel part. +Using UML as a Test Platform +============================ + +UML is an excellent test platform for device driver development. As +with most things UML, "some user assembly may be required". It is +up to the user to build their emulation environment. UML at present +provides only the kernel infrastructure. + +Part of this infrastructure is the ability to load and parse fdt +device tree blobs as used in Arm or Open Firmware platforms. These +are supplied as an optional extra argument to the kernel command +line:: + + dtb=filename + +The device tree is loaded and parsed at boottime and is accessible by +drivers which query it. At this moment in time this facility is +intended solely for development purposes. UML's own devices do not +query the device tree. + Security Considerations ----------------------- |