Re: [PATCH v2 1/8] dt-bindings: arm: Add Live Firmware Activation binding

[Krzysztof Kozlowski]

On Tue, Mar 17, 2026 at 11:33:27AM +0100, Andre Przywara wrote:
> The Arm Live Firmware Activation spec [1] describes updating firmware

A nit, subject: drop second/last, redundant "binding". The
"dt-bindings" prefix is already stating that these are bindings.
See also:
https://elixir.bootlin.com/linux/v6.17-rc3/source/Documentation/devicetree/bindings/submitting-patches.rst#L18

> images during runtime, without requiring a reboot. Update images might
> be deployed out-of-band, for instance via a BMC, in this case the OS
> needs to be notified about the availability of a new image.
> 
> This binding describes an interrupt that could be triggered by the

Describe hardware/firmware, not the binding.

> platform, to notify about any changes.
> 
> [1] https://developer.arm.com/documentation/den0147/latest/
> 
> Signed-off-by: Andre Przywara <andre.przywara@xxxxxxx>
> ---
>  .../devicetree/bindings/arm/arm,lfa.yaml      | 45 +++++++++++++++++++
>  1 file changed, 45 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/arm/arm,lfa.yaml
> 
> diff --git a/Documentation/devicetree/bindings/arm/arm,lfa.yaml b/Documentation/devicetree/bindings/arm/arm,lfa.yaml
> new file mode 100644
> index 000000000000..92f0564fd672
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/arm/arm,lfa.yaml
> @@ -0,0 +1,45 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/arm/arm,lfa.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Arm Live Firmware Activation (LFA)
> +
> +maintainers:
> +  - Andre Przywara <andre.przywara@xxxxxxx>
> +  - Sudeep Holla <sudeep.holla@xxxxxxx>
> +
> +description:
> +  The Arm Live Firmware Activation (LFA) specification [1] describes a
> +  firmware interface to activate an updated firmware at runtime, without
> +  requiring a reboot. Updates might be supplied out-of-band, for instance
> +  via a BMC, in which case the platform needs to notify an OS about pending
> +  image updates.
> +  [1] https://developer.arm.com/documentation/den0147/latest/
> +
> +properties:
> +  compatible:
> +    const: arm,lfa

Does specification has a version? Does it support version discovery?

> +
> +  interrupts:
> +    maxItems: 1
> +    description: notification interrupt for changed firmware image status
> +
> +required:
> +  - compatible
> +  - interrupts
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/interrupt-controller/arm-gic.h>
> +
> +    firmware {
> +        arm-lfa {

Node names should be generic. See also an explanation and list of
examples (not exhaustive) in DT specification:
https://devicetree-specification.readthedocs.io/en/latest/chapter2-devicetree-basics.html#generic-names-recommendation
If you cannot find a name matching your device, please check in kernel
sources for similar cases or you can grow the spec (via pull request to
DT spec repo).

arm-lfa is specific, so this could be as "fota" or "firmware-update"

Best regards,
Krzysztof