commit | 676be6a6f6c606be142c73e8527128f12b3f5a83 | [log] [tgz] |
---|---|---|
author | Hung-Te Lin <hungte@chromium.org> | Tue Apr 16 14:53:02 2019 |
committer | chrome-bot <chrome-bot@chromium.org> | Fri Apr 19 12:53:04 2019 |
tree | bd12410f6c2b222ece8590b865fdfb0185ae86a1 | |
parent | 3bda5d5bf5adbc1a7e368d6679c92752847d4cfd [diff] |
pack: sfx2: Support -V using native updater When running on Chrome OS normal images, or a test image with corrupted stateful partition, the system may not have 'unzip' in rootfs. Developers may still want to check the contents inside firmware updater, and we can use --unpack and some tiny scripting to simulate (not necessarily to be 100% the same) -V output. BUG=chromium:953275 TEST=chromeos-firmwareupdate -V Change-Id: I72610a6ea636a88fad4fb200e79dfdad6e3fd082 Reviewed-on: https://chromium-review.googlesource.com/1568914 Commit-Ready: Hung-Te Lin <hungte@chromium.org> Tested-by: Hung-Te Lin <hungte@chromium.org> Reviewed-by: Wei-Han Chen <stimim@chromium.org>
This repository contains the firmware updater (chromeos-firmwareupdate
) that will update firmware images related to verified boot, usually host (also known as AP, BIOS or MAIN) and EC (Embedded Controller).
Auto update is one of the most important feature in Chrome OS. Updating firmware is one of the most complicated process, since all Chromebooks come with firmware that implemented verified boot and must be able to update in background silently.
The firmware updater was made as an self-extracting archive with firmware images, updating logic, even utility programs.
In all modes, updater will try to preserve a list of known firmware data, for example the VPD sections (
RO_VPD
,RW_VPD
), and components inGBB
section likeHWID
.
Usually you can find the updater in /usr/sbin/chromeos-firmwareupdate
on a Chrome OS device (or the rootfs partition of a disk image).
To look at its contents (firmware images and versions) in machine friendly way:
chromeos-firmwareupdate --manifest
Currently we also support a human readable form:
chromeos-firmwareupdate -V
Usually for people who wants to “update all my firmware to right states”, do:
chromeos-firmwareupdate --mode=recovery
The
recovery
mode will try to update RO+RW if your write protection is not enabled, otherwise only RW.
If your are not sure about write protection status but you only want RW to be updated, run:
chromeos-firmwareupdate --mode=recovery --wp=1
The
--wp
argument will override you real write protection status.
If your want everything (RO and RW) to be updated and would like the updater to check WP state for you:
chromeos-firmwareupdate --mode=factory
The ChromeOS Auto Update (update_engine
) runs updater in a different way - a two-step trial process.
If you want to simulate and test that, do:
chromeos-firmwareupdate --mode=autoupdate --wp=1
The updater is provided by the virtual/chromeos-firmware
package in Chromium OS source tree, which will be replaced and includes the chromeos-base/chromeos-firmware-${BOARD}
package in private board overlays.
To build an updater locally, in chroot run:
emerge-${BOARD} chromeos-firmware-${BOARD}
If your board overlay has defined USE flags bootimage
or cros_ec
, chromeos-firwmare-${BOARD}
package will add dependency to firmware and EC source packages (chromeos-bootimage
and chromeos-ec
), and have the firmware images in /build/${BOARD}/firmware/{image,ec}.bin
.
In other words, you can remove
bootimage
andcros_ec
in branches that you don't need firmware from source, for example the factory branches or ToT, especially if there are external partners who only has access to particular board private overlays. To do that, find themake.conf
in board overlay and addUSE="-bootimage -cros_ec"
.
The firmware updater packages lives in private board overlays: src/private-overlays/overlay-${BOARD}-private/chromeos-base/chromeos-firmware-${BOARD}/chromeos-firmware-${BOARD}-9999.ebuild
. Find a template here in chromiumos-base/chromeos-firmware-null.
Usually there are few fields you have to fill:
A reference to the Main (AP) firmware image, which usually comes from emerge-${BOARD} chromeos-booimage
then /build/${BOARD}/firmware/image.bin
.
Usually this implies both RO and RW. See CROS_FIRMWARE_MAIN_RW_IMAGE
below for more information.
You have to run
ebuild-${BOARD} chromeos-firmware-${BOARD}.ebuild manifest
whenever you've changed the image files (CROS_FIRMWARE_*_IMAGE
).
A reference to the Main (AP) firmware image and only used for RW sections.
If this value is set, CROS_FIRMWARE_MAIN_IMAGE
will be used for RO and this will be used for RW.
A reference to the Embedded Controller (EC) firmware image, which usually comes from emerge-${BOARD} chromeos-ec
then /build/${BOARD}/firmware/ec.bin
.
The firmware updater is built by running pack_firmware.py
, which collects firmware image files, and then archived by running shar
, with a special bootstrap SFX script pack/sfx.sh
.
Since the verified boot has been evolved with so much differences, we put the updating logic in different files according to the generation of firmware: pack/dist/updater*.sh
. Most Chromebooks today should use updater5.sh
.
Usually we will increase a “logic version” when the verified boot has been changed so much that the updater code for previous versions would almost won't work. Currently we have defined these versions (Use Developer Info page to find the mapping from board names to product names):
Starting from M70, we will migrate all projects to a newly native code based updater as “updater v5”. After that there won't be any versions. See go/updater5 for more details.
This will be mapped to what you should set in the CROS_FIRMWARE_SCRIPT
value in ebuild files.
For details about package format, check pack/README.md.
Here's a detailed list of how each updater mode works:
--mode=autoupdate
: Invoked by update_engine
when a payload is installed.
update_engine
will invoke chromeos-setgoodfirmware
after 60 secs, which will update or mark booted RW firmware to active.CROS_FIRMWARE_MAIN_IMAGE
. If yes, go 2. Otherwise, do --mode=recovery
.--mode=recovery
: Invoked by recovery shim after installed.
Note in
recovery
mode, theHWID
and flags inGBB
are both preserved.
--mode=factory
: A special recovery mode for factory initial imaging that always runs as wp=0
and NOT preserving GBB flags.Note in
factory
mode, onlyHWID
inGBB
is preserved. The GBB flags will be changed because in factory process we need to overwrite the flags so we can ensure developer mode or other factory friendly settings were turned on in first boot.
--mode=legacy
: A special mode that only updates RW_LEGACY
.
--mode=output
: A special mode for updater with multiple sets of images.
--output_dir
).