This would also help, for example, to go back to the nonfree firmware when the
alternate firmware did not work as well as hoped. It would also allow flashing
the firmware using an SPI programmer if everything went very wrong indeed.
This allows a device to identify with different streams, for instance a Lenovo
laptop could have a coreboot firmware or a AMI firmware. The GUIDs would be the
same, but switching firmware would only be done rarely and very carefully.
Another example would be switching the Broadcom BCM57xx nework adaptors from the
vendor nonfree firmware with a signed PXE image, to the free software reverse
engineered driver with no PXE support (and thus no signed DXE) at all.
It is expected firmware would have additional metadata something like this:
...
<branch>sdcc</branch>
<description>
<p>
This is an alternate firmware built by the community using only free
software tools.
</p>
</description>
<requires>
<id compare="ge" version="1.5.0">org.freedesktop.fwupd</id>
<client>switch-branch</client>
</requires>
...
Additionally, alternate branch firmware will not be returned for clients not
setting the FWUPD_FEATURE_FLAG_SWITCH_BRANCH before the GetReleases request.
Conceptually we were trying to stuff subtly different actions into one vfunc:
* Read firmware from the device to update the verification checksums
* Read a firmware blob from the device for debugging
For the first action we might want to mask out the sections of the flash with
serial numbers (so the verification hashes match the ones published on the LVFS)
and for the second we want just a raw ROM file from the hardware with no
pre-processing that we can compare against an external SPI dumper.
Split out ->dump_firmware to get the raw blob, and allow plugins to also
implement ->read_firmware() if they have to mask out specific offsets or remove
specific images from the FuFirmware container.
In the common case when masking is not required, fall back to using a 'binary'
FuFirmware automatically to make most plugins simpler.
At the moment there are commands to convert one file format to another, but not
to 'merge' or alter them. Some firmware files are containers which can store
multiple images, each with optional id, idx and addresses.
This would allow us to, for instance, create a DfuSe file with two different
raw files that are flashed to different addresses on the SPI flash. It would
also allow us to create very small complicated container formats for fuzzing.
This can be used by writing a `firmware.builder.xml` file like:
<?xml version="1.0" encoding="UTF-8"?>
<firmware gtype="FuBcm57xxFirmware">
<version>1.2.3</version>
<image>
<version>4.5.6</version>
<id>header</id>
<idx>456</idx>
<addr>0x456</addr>
<filename>header.bin</filename>
</image>
<image>
<version>7.8.9</version>
<id>payload</id>
<idx>789</idx>
<addr>0x789</addr>
<data>aGVsbG8=</data>
</image>
</firmware>
...and then using something like:
# fwupdtool firmware-convert firmware.builder.xml firmware.dfu builder dfu
For containers with multiple images it is sometimes very helpful to know what
file they've been loaded from. This would also allow us to 'explode' the
firmware container into seporate image files on disk.
The function fu_firmware_add_image() has the comment text 'If an image with the
same ID is present it is replaced' which has not been true for some time.
This was removed, as the common case of adding two images with no ID would only
leave one. However, some plugins do actually want to dedupe on the ID or IDX,
so provide a flag they can set which enables this functionality without
introducing regressions into other plugins.
I2C doesn't have any specification for what is a probe and what is a more
destructive action. Sending tx_buf out on the i2c bus to a generic address
might not be safe in all cases.
To prevent this, use a HWID to check the machine DMI value during device
creation before ->probe() or ->setup() is called on the device.
If the device parent is added using fu_device_add_parent_guid() or ParentGuid
from a quirk file then the child is not returned in fu_device_get_children() by
design as the physical ID will be likely different.
This means we cannot reliably 'depsolve' the order in FuDevice as we need the
full list of devices that might be parents. The existing algorithm had several
logical problems when dealing with more than a single parent and child.
The FuDeviceList object is the right place to do this as it knows about all
added devices on the system.
This means the addition of a logical device causes the root logical device
(and all it's children, and grandchildren) to be re-ordered. This allows
firmware on deeply nested composite devices like hubs to be installed in the
correct order.
Print the sysfs path for devices deriving from FuUdevDevice, which also allows
us to use FU_UDEV_DEVICE_DEBUG without monkey-patching the plugins that also
define a device_class->to_string() vfunc.
If the device node actually provides a vendor string, always use that before
falling back. The flag was initially designed to fall back in the event the NVMe
device does not declare a valid sysfs vendor ID.
