[PATCH v3 0/2] bootstd: New bootmeth for RAUC A/B systems

[Neil Armstrong]

On 05/06/2025 22:02, Tom Rini wrote:
> On Thu, Jun 05, 2025 at 07:46:54PM +0200, neil.armstrong at linaro.org wrote:
>> Hi,
>>
>> On 04/06/2025 14:15, Martin Schwan wrote:
>>> This series implements a new bootmeth for RAUC A/B systems. RAUC (Robust
>>> Auto Update Controller) is a lightweight update client, providing "Safe
>>> and Secure OTA Updates for Embedded Linux". See the following links for
>>> more information about RAUC:
>>>
>>>     https://rauc.io/
>>>     https://rauc.readthedocs.io/en/latest/
>>>
>>> PHYTEC uses RAUC in its Yocto based distribution "Ampliphy" as the
>>> default way of updating embedded devices based on PHYTEC hardware. So
>>> far, the logic selecting the correct partitions and files to boot was
>>> being implemented in the U-Boot environment. While this is a
>>> straightforward way to do it, adding and supporting new platforms became
>>> somewhat tedious and is platform-specific. The introduction of U-Boot's
>>> "Standard Boot" provided a convincing alternative, promising a simpler
>>> and more portable way of booting, even for RAUC systems. This led me to
>>> implement a new bootmeth supporting RAUC A/B systems. Note, that this
>>> new bootmeth is not proprietary to PHYTEC products and is designed to
>>> work on other hardware with a RAUC A/B system, too.
>>>
>>> The bootmeth currently only supports symmetric A/B partitioning layouts.
>>> E.g. A/rescue is not (yet) supported. The partition indexes and default
>>> slot tries can be specified via configuration options.
>>>
>>> For now, the bootmeth_rauc uses a similar approach for loading the
>>> Kernel and device tree as the bootmeth_script, in that it requires a FIT
>>> containing a U-Boot script loading the desired distro. It could be
>>> possible to support booting without a script and load the Kernel and DT
>>> directly with this bootmeth, but I found the script method to be very
>>> flexible for now, in letting the distro decide what to load.
>>>
>>> The bootmeth_rauc was tested on a phyBOARD-Pollux i.MX8M Plus [1] with
>>> BSP-Yocto-Ampliphy-i.MX8MP-PD24.1.2 [2].
>>>
>>> Supported boot devices are currently only MMC devices, but it should be
>>> possible to add SPI flashes in the future.
>>
>> It's quite a late comment, but this implementation has really nothing
>> specific to do with MMC, you could just support any block device.
>>
>> So if you could just add a config selecting the block type, defaulting
>> to mmc, this could be used on any block like USB, UFS, NVMe, ... with
>> almost 0 changes.
> 
> I raised this with v1. The challenge is that RAUC itself doesn't yet
> support non-MMC options. If/when that changes it's easy to update here.
> 

Ack thx, indeed the code change would be minimal

Neil