github/acrn-hypervisor
1
0
Fork 0
mirror of https://github.com/projectacrn/acrn-hypervisor.git synced 2025-09-06 03:10:13 +00:00
Code Issues Projects Releases Wiki Activity

doc: remove UEFI/de-privilege boot mode from docs

Browse Source 
Also clear Linux is no longer supported either as SOS or post-launched VM kernel.

- When it mentions clear Linux, mostly replaced by Ubuntu.
- remove all contents re/lated to "UEFI boot".
- remove the term de-privilege mode, and direct mode as well.

Tracked-On: #5197
Signed-off-by: Zide Chen <zide.chen@intel.com>
This commit is contained in:
Zide Chen
2020-08-21 10:45:07 -07:00
committed by David Kinder
parent 75ecc0e3b1
commit f945fe27ab
12 changed files with 24 additions and 127 deletions
Download Patch File Download Diff File Expand all files Collapse all files

60
doc/introduction/index.rst
View File

@@ -67,7 +67,7 @@ VM. The service VM can access hardware resources directly by running
native drivers and it provides device sharing services to the user VMs
through the Device Model. Currently, the service VM is based on Linux,
but it can also use other operating systems as long as the ACRN Device
Model is ported into it. A user VM can be Clear Linux*, Ubuntu*, Android*,
Model is ported into it. A user VM can be Ubuntu*, Android*,
Windows* or VxWorks*. There is one special user VM, called a
post-launched Real-Time VM (RTVM), designed to run a hard real-time OS,
such as Zephyr*, VxWorks*, or Xenomai*. Because of its real-time capability, RTVM
@@ -394,71 +394,21 @@ and many other features.
Boot Sequence
*************
.. _systemd-boot: https://www.freedesktop.org/software/systemd/man/systemd-boot.html
.. _grub: https://www.gnu.org/software/grub/manual/grub/
.. _Slim Bootloader: https://www.intel.com/content/www/us/en/design/products-and-solutions/technologies/slim-bootloader/overview.html
ACRN supports two kinds of boots: **De-privilege boot mode** and **Direct
boot mode**.
De-privilege boot mode
======================
**De-privilege boot mode** is loaded by ``acrn.efi`` under a UEFI
environment. The Service VM must be the first launched VM, (i.e. VM0).
In :numref:`boot-flow`, we show a verified Boot Sequence with UEFI
on an Intel Architecture platform NUC (see :ref:`hardware`).
.. graphviz:: images/boot-flow.dot
:name: boot-flow
:align: center
:caption: ACRN Hypervisor De-privilege boot mode Flow
The Boot process proceeds as follows:
#. UEFI verifies and boots the ACRN hypervisor and Service VM Bootloader.
#. UEFI (or Service VM Bootloader) verifies and boots the Service VM kernel.
#. The Service VM kernel verifies and loads the ACRN Device Model and the Virtual
bootloader through ``dm-verity``.
#. The virtual bootloader starts the User-side verified boot process.
.. note::
To avoid a hardware resources conflict with the ACRN hypervisor, UEFI
services shall not use IOMMU. In addition, we only currently support the
UEFI timer with the HPET MSI.
In this boot mode, both the Service and User VM boot options (e.g. Linux
command-line parameters) are configured following the instructions for the EFI
bootloader used by the Operating System (OS).
* In the case of Clear Linux, the EFI bootloader is `systemd-boot`_ and the Linux
kernel command-line parameters are defined in the ``.conf`` files.
.. note::
A virtual `Slim Bootloader`_ called ``vSBL``, can also be used to start User VMs. The
:ref:`acrn-dm_parameters` provides more information on how to boot a
User VM using ``vSBL``. Note that in this case, the kernel command-line
parameters are defined by the combination of the ``cmdline.txt`` passed
on to the ``iasimage`` script and in the launch script, via the ``-B``
option.
Direct boot mode
================
The ACRN hypervisor can be booted from a third-party bootloader
directly, called **Direct boot mode**. A popular bootloader is `grub`_ and is
directly. A popular bootloader is `grub`_ and is
also widely used by Linux distributions.
:ref:`using_grub` has a introduction on how to boot ACRN hypervisor with GRUB.
In :numref:`boot-flow-2`, we show the **Direct boot mode** sequence:
In :numref:`boot-flow-2`, we show the boot sequence:
.. graphviz:: images/boot-flow-2.dot
:name: boot-flow-2
:align: center
:caption: ACRN Hypervisor Direct boot mode Boot Flow
:caption: ACRN Hypervisor Boot Flow
The Boot process proceeds as follows:
@@ -482,7 +432,7 @@ launch scripts.
.. note::
`Slim Bootloader`_ is an alternative boot firmware that can be used to
boot ACRN in **Direct boot mode**. The `Boot ACRN Hypervisor
boot ACRN. The `Boot ACRN Hypervisor
<https://slimbootloader.github.io/how-tos/boot-acrn.html>`_ tutorial
provides more information on how to use SBL with ACRN.