Re: [PATCH v2 1/8] dt-bindings: arm: Add Live Firmware Activation binding
From: Krzysztof Kozlowski <krzk@kernel.org>
Date: 2026-03-18 08:04:49
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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.
quoted hunk ↗ jump to hunk
platform, to notify about any changes. [1] https://developer.arm.com/documentation/den0147/latest/ Signed-off-by: Andre Przywara <andre.przywara@arm.com> --- .../devicetree/bindings/arm/arm,lfa.yaml | 45 +++++++++++++++++++ 1 file changed, 45 insertions(+) create mode 100644 Documentation/devicetree/bindings/arm/arm,lfa.yamldiff --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@arm.com> + - Sudeep Holla <sudeep.holla@arm.com> + +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