acrn-hypervisor/doc/tutorials/enable_s5.rst

131 lines
4.7 KiB
ReStructuredText

.. _enable-s5:
Enable S5
#########
About System S5 Support
***********************
S5 refers to the ACPI “soft off” system state. ACRN system S5 support enables
you to gracefully shut down or reset the whole system when multiple VMs are
running. This is done by requesting and waiting for all pre-launched and
post-launched VMs to gracefully shut themselves down before the Service VM
triggers a system-wide shutdown or reset.
We recommend using ACRN system S5 support to shut down or reset a system unless
you have other mechanisms in place to protect external storage from being
corrupted by a mechanical off.
Dependencies and Constraints
****************************
Consider the following dependencies and constraints:
* ACRN system S5 support is hardware neutral but requires the deployment of a
daemon (named Lifecycle Manager) in all VMs. The Lifecycle Manager manages
power state transitions.
* The COM2 port is reserved for the Lifecycle Manager to communicate requests
and responses. Console vUARTs and inter-VM UART connections should avoid using
COM2 as an interface.
* The S5 feature needs a communication vUART to control a User VM. However, you
don't need to configure a vUART connection for S5 via the ACRN Configurator,
because ACRN code already has a vUART connection between the Service VM and
User VMs by default.
Example Configuration
*********************
The following steps show how to enable S5 by extending the information provided
in the :ref:`gsg`. The scenario has a Service VM and one Ubuntu post-launched
User VM.
#. On the development computer, build the Lifecycle Manager daemon::
cd acrn-hypervisor
make life_mngr
The build generates files in the ``build/misc/services/life_mngr`` directory.
#. Copy ``life_mngr.conf``, ``s5_trigger_linux.py``, ``life_mngr``, and
``life_mngr.service`` into the Service VM and User VM.
These commands assume you have a network connection between the development
computer and target system. You can also use a USB stick to transfer files.
.. code-block:: bash
scp build/misc/services/s5_trigger_linux.py acrn@<target board address>:~/
scp build/misc/services/life_mngr acrn@<target board address>:~/
scp build/misc/services/life_mngr.service acrn@<target board address>:~/
scp build/misc/services/life_mngr.conf acrn@<target board address>:~/
Log in to the target system and run the following commands::
sudo mkdir /etc/life_mngr
sudo mv ~/life_mngr.conf /etc/life_mngr/
sudo mv ~/life_mngr.service /lib/systemd/system/
sudo mv ~/life_mngr /usr/bin/
#. Copy ``user_vm_shutdown.py`` from the development computer into the Service
VM::
scp misc/services/life_mngr/user_vm_shutdown.py acrn@<target board address>:~/
#. ACRN code sets the COM2 (``/dev/ttyS1``) as the default communication port of
the User VM, so we need only check the S5 vUART of the Service VM. Use the
following steps to get the Service VM S5 connection information.
Log in to the Service VM and run the command ``cat /etc/serial.conf`` to get
the connection information between the Service VM and User VM. Output
example:
.. code-block:: console
# User_VM_id: 1
/dev/ttyS8 port 0X9008 irq 0 uart 16550A baud_base 115200
This example means the Service VM uses the ``/dev/ttyS8`` connection to the
User VM's ``/dev/ttyS1``.
#. Configure the S5 feature:
a. In the Service VM, edit the following options in
``/etc/life_mngr/life_mngr.conf``. Make sure ``VM_NAME`` is the Service VM
name specified in the ACRN Configurator. Replace ``/dev/ttyS8`` with your
Service VM's S5 vUART, if it was different from the example in the
previous step.
.. code-block:: bash
VM_TYPE=service_vm
VM_NAME= ACRN_Service_VM
DEV_NAME=tty:/dev/ttyS8
ALLOW_TRIGGER_S5=/dev/ttySn
#. In the User VM, edit the following options in
``/etc/life_mngr/life_mngr.conf``. Replace ``<User VM name>`` with the
VM name specified in the ACRN Configurator.
.. code-block:: bash
VM_TYPE=user_vm
VM_NAME=<User VM name>
DEV_NAME=tty:/dev/ttyS1
ALLOW_TRIGGER_S5=/dev/ttySn
#. Enable ``life_mngr.service`` and restart the Service VM and User VM::
sudo chmod +x /usr/bin/life_mngr
sudo systemctl enable life_mngr.service
sudo reboot
#. To trigger a system S5, run ``s5_trigger_linux.py`` in the Service VM.
The Service VM shuts down (transitioning to the S5 state) and sends a
poweroff request to shut down the User VM.
.. note::
The S5 state is not automatically triggered by a Service VM shutdown; you
need to run ``s5_trigger_linux.py`` in the Service VM.