From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 1723B10706ED for ; Wed, 18 Mar 2026 16:01:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id: Content-Transfer-Encoding:Content-Type:In-Reply-To:From:References:To:Subject :MIME-Version:Date:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=f1zjxHeHTb4trDm2/L79bBPANq6xqVwqdU3EGuv0aGE=; b=D/Q3KkFsuqx4t6 ceXkBKnGogJ6rH1jWscRdPyWaFLk6CoETdgwNFFzvprkwdPHb7/EvwvB9c78tTbRks/TEUWDT744/ KTgNnppVfjEFXBFNEq91ElbaCqRjHt1h2oeMTnfv4PvYFaYcX2BR96rYRi2TdlNesgkYdc70pmq8/ ExLx5hSOfvdQpUFTzfknGNBUXQze7WwBd8Wjfyn2sdhHKz5iaXKXLUnKSKKJLlzIMzcKZMJbgXUnh zaZn/hr1knvbuQLg1oa7r0T3ttl/uuGQN7gkxfLE6YKZlea1/MsGwTmYVQVOSRp3zTfyZDWqbRf/N AcE6bH++i7U0K+21sQ/Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1w2tKZ-00000008sHC-25Dr; Wed, 18 Mar 2026 16:01:11 +0000 Received: from desiato.infradead.org ([2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1w2tKY-00000008sGW-06qV for linux-arm-kernel@bombadil.infradead.org; Wed, 18 Mar 2026 16:01:10 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=Content-Transfer-Encoding:Content-Type :In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date:Message-ID: Sender:Reply-To:Content-ID:Content-Description; bh=f1zjxHeHTb4trDm2/L79bBPANq6xqVwqdU3EGuv0aGE=; b=owtDRiptuugxeNZQNd/N6mebdF 1tbH2INKzbkzF3l+GWjfH3f5S+hc1S0LBCIriEzf5KUEXB5PMxgZhwd4dQLWIbLcI4ShY8vfSfcy6 5JB5zgN+HUkPesYfgHe7tbiCJbxjJl/UELYuddIGWH3b2fKUrSfs506Qy+NrM8kLhL4Vtsje2u1W9 MyvkJJ76XiKKrYfGcPN6URnYDUxcLWA2Nb31qhCpsKqL7zgE6iUrn09ugDfYbpp/3GgXrJ0gTrCgJ D6IUmCB29huPvVfYX+ytndHkpO6aXZeICqCrxtDuIMSAOIoTHGwAfD9z0mydp9dp91IHoQ23H0lgV 2DIOpwwQ==; Received: from foss.arm.com ([217.140.110.172]) by desiato.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1w2tKU-0000000Beps-1Ffj for linux-arm-kernel@lists.infradead.org; Wed, 18 Mar 2026 16:01:08 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 75B7D1A25; Wed, 18 Mar 2026 09:00:58 -0700 (PDT) Received: from [192.168.178.23] (usa-sjc-mx-foss1.foss.arm.com [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id F200B3F73B; Wed, 18 Mar 2026 09:01:00 -0700 (PDT) Message-ID: <73a2e7fa-ab30-4d81-a4ff-0292b6adf346@arm.com> Date: Wed, 18 Mar 2026 17:00:13 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 1/8] dt-bindings: arm: Add Live Firmware Activation binding To: Krzysztof Kozlowski References: <20260317103336.1273582-1-andre.przywara@arm.com> <20260317103336.1273582-2-andre.przywara@arm.com> <20260318-inventive-tortoise-of-romance-c7ceba@quoll> Content-Language: en-US From: Andre Przywara In-Reply-To: <20260318-inventive-tortoise-of-romance-c7ceba@quoll> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260318_160106_652881_C9C08DEE X-CRM114-Status: GOOD ( 25.24 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Rob Herring , Conor Dooley , devicetree@vger.kernel.org, Lorenzo Pieralisi , Trilok Soni , Salman Nabi , vwadekar@nvidia.com, linux-kernel@vger.kernel.org, Sudeep Holla , vsethi@nvidia.com, Krzysztof Kozlowski , Nirmoy Das , linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi, On 3/18/26 09:04, Krzysztof Kozlowski wrote: > 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 Sure, will fix. >> 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. Right, sorry, this slipped through. >> platform, to notify about any changes. >> >> [1] https://developer.arm.com/documentation/den0147/latest/ >> >> Signed-off-by: Andre Przywara >> --- >> .../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 >> + - Sudeep Holla >> + >> +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? Yes and yes. there is a mandatory LFA_GET_VERSION call, with major and minor version. And please note that the discovery of the firmware functionality doesn't rely on DT (or ACPI) at all - it uses discoverable SMCCC calls instead. We just need this DT node to convey the (optional) platform specific interrupt number. >> + >> + interrupts: >> + maxItems: 1 >> + description: notification interrupt for changed firmware image status >> + >> +required: >> + - compatible >> + - interrupts >> + >> +additionalProperties: false >> + >> +examples: >> + - | >> + #include >> + >> + 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" OK, will try to come up with a good name. Thanks for the review! Cheers, Andre > > Best regards, > Krzysztof >