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 96994C982E6 for ; Mon, 21 Sep 2026 16:20:07 +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:In-Reply-To: Content-Type:MIME-Version:References:Message-ID:Subject:To:From:Date:Reply-To :Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=yUk6xrHyMi4gFz7Q2nWEkOHH5s2Hu2ne+l7Vi+ljp6Q=; b=pAYz+b5jq2dZJZQvX01Oxyt76g VdLF/E+KQXqwmmP5Rouvme0IJrNaHBO2S5F47d59YdTfoTS4NkS7sqSEB4RD8sr3i00KWdPNVVlHM MMuPK8QPZfzDPmiNf0WMFsqwg3gk6AzHLae1JTUESMAWEcfy5Xlw8/KC49UqrQNBdGQKqV6s4M7Iw UPIxnp7zVcn97Bi90gm6x1M5YF99ZTGKlwz99FmHbOi0x8T/yRorM29VQXlZXxAmzoLqXkqzNFq7L cRoOxPy2w6riKa+EV/CGoWLk7/gMZijDV1lQLq0Q1KX0MPH4ZzmI0cZWt7tkqHrjZIb47PryqRtjS A4yHUm7Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1x8gkK-00000002oH6-2aGD; Mon, 21 Sep 2026 16:20:00 +0000 Received: from sea.source.kernel.org ([172.234.252.31]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1x8gkJ-00000002oGv-0MSB for linux-arm-kernel@lists.infradead.org; Mon, 21 Sep 2026 16:19:59 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id D26DB429D6; Mon, 21 Sep 2026 16:19:58 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4FA1D1F00893; Mon, 21 Sep 2026 16:19:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790007598; bh=yUk6xrHyMi4gFz7Q2nWEkOHH5s2Hu2ne+l7Vi+ljp6Q=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=UbxK2uxURejDJlalyThSRTeTHPax9jSfShPdzCRZkP3u0RZSL8ufyoda7eOKicwe8 A6vKtma1Z4LdM6+QhHs2KhURVQw/tQweIBomV0Fs0bIxphqHuqdBdXTH6uj89tQocL QmEawNd3P4dx1hmF2HM1b2KwGFi7NihQpZZ4x/+VT8vNVTVnWrDKAKXogwLjhJV5pv XEV+9G4BACeyxqQh1+IIFCDVF8Cx/+xCnMajPrKrlZrazEdt3drIXiGv21VItc1Uek QjDuJj4USMvKbR2MO0l6ymVn/GNsoa5SsO39JaNz86/hs3yczaiN+IweshvtnjgRVU Ots9izkGZaPtw== Date: Mon, 21 Sep 2026 17:19:53 +0100 From: Sudeep Holla To: Andre Przywara Subject: Re: [PATCH v4 8/8] firmware: smccc: lfa: add sysfs ABI documentation Message-ID: <20260921-essential-inquisitive-spaniel-9801eb@sudeepholla> References: <20260918141112.2115555-1-andre.przywara@arm.com> <20260918141112.2115555-9-andre.przywara@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260918141112.2115555-9-andre.przywara@arm.com> 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 , vsethi@nvidia.com, Salman Nabi , Rob Herring , Lorenzo Pieralisi , linux-kernel@vger.kernel.org, Varun Wadekar , Trilok Soni , devicetree@vger.kernel.org, Conor Dooley , Nirmoy Das , Krzysztof Kozlowski , 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 On Fri, Sep 18, 2026 at 04:11:11PM +0200, Andre Przywara wrote: > Document the sysfs attribute files as exported by the LFA driver. > Looking at the sysfs output in 2/8 message log, activation_pending is missing from the documentation. > Signed-off-by: Andre Przywara > --- > Documentation/ABI/testing/sysfs-firmware-lfa | 106 +++++++++++++++++++ > 1 file changed, 106 insertions(+) > create mode 100644 Documentation/ABI/testing/sysfs-firmware-lfa > > diff --git a/Documentation/ABI/testing/sysfs-firmware-lfa b/Documentation/ABI/testing/sysfs-firmware-lfa > new file mode 100644 > index 0000000000000..afd349af9cf14 > --- /dev/null > +++ b/Documentation/ABI/testing/sysfs-firmware-lfa > @@ -0,0 +1,106 @@ > +What: /sys/firmware/lfa > +Date: May 2026 > +Contact: Andre Przywara > +Description: > + The Arm Live Firmware Activation (LFA) spec describes an > + interface between platform firmware (an agent) and any user > + on the non-secure side (like the Linux kernel) to activate > + pending firmware updates at runtime. The actual firmware > + update would be provided independently (out-of-band, or > + via any existing explicit firmware update mechanisms), then, > + if supported, can be activated immediately, without rebooting > + the system. > + This directory contains one directory for each of the LFA > + capable firmware images supported by the agent, identified by > + its GUID. Within each directory, the same set of sysfs files > + provides access to the properties and actions for this > + particular firmware image. > + > +What: /sys/firmware/lfa//activate > +Date: May 2026 > +Contact: Andre Przywara > +Description: > + (WO) Write a boolean 'true' value to trigger the > + activation of that firmware component. An update must be > + pending for this to be successful. > + > +What: /sys/firmware/lfa//activation_capable > +Date: May 2026 > +Contact: Andre Przywara > +Description: > + (RO) A boolean value to show whether this firmware image is > + capable of being activated. > + > +What: /sys/firmware/lfa//auto_activate > +Date: May 2026 > +Contact: Andre Przywara > +Description: > + (RW) Write a boolean 'true' value to allow a firmware image > + to be automatically activated once a new firmware update > + becomes available ("pending"). This depends on a working > + notification scheme, for instance via an ACPI notification > + or an interrupt to notify the kernel. > + > +What: /sys/firmware/lfa//cancel > +Date: May 2026 > +Contact: Andre Przywara > +Description: > + (WO) Write a boolean 'true' value to cancel a recently > + triggered activation, if that has not finished yet. > + > +What: /sys/firmware/lfa//cpu_rendezvous > +Date: May 2026 > +Contact: Andre Przywara > +Description: > + (RO) A boolean value to show whether this image requires > + a CPU rendezvous in firmware to be activated. If true, this > + means all CPUs will enter the firmware during the activation > + process, so will not be able to execute kernel code or > + handle interrupts for a brief moment. What use does the userspace have with this 'activation_pending' and 'may_reset_cpu' ? We should drop them unless you convince otherwise. -- Regards, Sudeep