From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 395EC606A31D for ; Sat, 31 Oct 2026 12:01:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=RrZySRLr; dkim=pass (2048-bit key, unprotected) header.d=posteo.net header.i=@posteo.net header.a=rsa-sha256 header.s=1984.8680eb header.b=SViwAUTN DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:Message-ID:References:In-Reply-To:Subject:Cc:To:From:Date: MIME-Version:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Unsubscribe-Post: List-Owner; bh=Z8M3dkO8VWTPT7niqbjTbaNM/dFwMeWR+hAhAlcZSaE=; b=RrZySRLrhSyhHv ZbnoBWz8vxeh1HwPLlUeCvcVLwv8pKJFVz4V8D1aCHUhhpxTXsSotsdXMJFIgcnsWp2hB7BghVOXG LNPLebdIrWQ1xsbJZlLyz1bG81RBL8mlOkjTIZ1v8ieKIlvk4xbZg6q5qungRqm+iucOtLI/CiYvM VY28vKKEADjcgDW/wMkd1pL98PlZxFiCdqP2vOHqt3cO2ynLBXQZn/ZJsX+dwLflc8Kv8lHOGR4/o xcjToqI/sUyihK+p/lRPgXXGkJX+gwuLzeU99hZt2N/0onTPnK3eA2oEvaX5Mnv5CG80noI76wSNL ZwkyFuk0jFncIovfCJGQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xN7la-0000000DHOE-0yQd; Sat, 31 Oct 2026 12:00:58 +0000 Received: from mout02.posteo.de ([185.67.36.66]) by bombadil.infradead.org with esmtps (Exim 4.100.1 #2 (Red Hat Linux)) id 1xN7lW-0000000DHNc-43jM for linux-arm-kernel@lists.infradead.org; Sat, 31 Oct 2026 12:00:56 +0000 Received: from submission (posteo.de [185.67.36.169]) by mout02.posteo.de (Postfix) with ESMTPS id 42E4824013B for ; Sat, 31 Oct 2026 13:00:28 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=posteo.net; s=1984.8680eb; t=1793448028; bh=Z8M3dkO8VWTPT7niqbjTbaNM/dFwMeWR+hAhAlcZSaE=; h=MIME-Version:Date:From:To:Cc:Subject:Message-ID:Content-Type: Content-Transfer-Encoding:From; b=SViwAUTNyMNFROcqxCKLRZ0BtFCXJiGPVADeeukqK0di9ogIQr6ItJKkAOtqMinfj kJOPr+SRIoX84L4pjzNcpN88oRx7Zbku6KEYRxIJp3LaxArjBSeLIR26098z+ag9Qg ik5LPtm8qBGDMTNnvEttlTzHKIGUQf/Xo8Gvr0EK5xLCs6P5XRb8xifbAWBx5fPGda Z/ZZS8/yDZkp1uf2LWL65M6lPPjZa5wHk/QhkeB3MqfVBdxuuykARKqwvd4bKpjnjb hg7od82KozrRp63nx/D/aREhvwT0zhUe8KmxWzIHLQPErC9HCCVgzKnUk2ffxELqVM +oQad9jwQoRqQ== Received: from customer (localhost [127.0.0.1]) by submission (posteo.de) with ESMTPSA id 4jGxP55GZcz6tsb; Sat, 31 Oct 2026 13:00:25 +0100 (CET) X-Archived-By: MIME-Version: 1.0 Date: Sat, 31 Oct 2026 12:00:27 +0000 From: mateusz.nowicki@posteo.net To: Arnd Bergmann Cc: Marek Vasut , Alexandre Torgue , Maxime Coquelin , Thomas BOURGOIN , Rob Herring , krzk+dt@kernel.org, Conor Dooley , Lionel DEBIEVE , Amelie DELAUNAY , Patrice Chotard , devicetree@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, kernel , Geert Uytterhoeven , "laurent.pinchart" , Fabrice GASNIER , Stefano Babic , Etienne Carriere Subject: Re: [PATCH] arm64: dts: st: fix arm,smc-id of the SMC watchdog on stm32mp2 In-Reply-To: References: <20260907091400.55954-1-mateusz.nowicki@posteo.net> <7ee09655-2fef-4334-b0aa-b56f7ae03f74@foss.st.com> <1b14e1e4-962f-4391-91fd-b09143641643@nabladev.com> Message-ID: Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20261031_050055_314107_6F825F17 X-CRM114-Status: GOOD ( 19.92 ) X-Spam-Score: -4.4 (----) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" X-Spam-Status: No, score=-5.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 Hi Arnd, Marek, On Sat, Oct 31, 2026, Arnd Bergmann wrote: > I think for the kernel it's pretty clear, we have to revert it > to avoid the regression on old firmware, at least for boards > that have ever shipped with that version. I count eight boards > for stm32mp2 in upstream Linux, do we know how many of them > are affected by the ABI break? As the author of the patch, I looked at where both IDs come from. 0xb200005a only ever matched ST's *downstream* OP-TEE 3.19.0-stm32mp, the base of the first OpenSTLinux releases for stm32mp25 (last update 2024-11-25). No *upstream* OP-TEE release ever used it on stm32mp2. 0xbc000000 is used by: - ST's downstream OP-TEE since 4.0.0-stm32mp-r1 (2024-11-04), the base of the current OpenSTLinux releases, up to 4.8.0-stm32mp-r1 (2026-10-27) - upstream OP-TEE since 4.8.0 (2025-10-24), commit 11d68b6754 ("plat-stm32mp2: enable watchdog SMC service"). Before 4.8.0 upstream OP-TEE has no watchdog SMC service on stm32mp2 at all. On the Linux side: - 89fca38168c9 (v6.7, 2023-09) added the node with 0xb200005a, which matched the 3.19 based firmware of that time. - 7a57b1bb1afb and e9b03ef21386 (v6.15, 2025-03) added stm32mp21 with 0xbc000000 and stm32mp23 with 0xb200005a on the same day. - ae4d08bbe3f4 (v7.4 merge window) moved stm32mp23 and stm32mp25 to 0xbc000000. So from v6.7 to v7.3 the watchdog never worked with upstream OP-TEE, nor with ST's own firmware since November 2024: arm_smc_wdt fails to probe with -EIO and an IWDG started by the boot loader is never refreshed. That is how I found it on a STM32MP257F-DK with upstream OP-TEE 4.10. A revert would move the breakage to everybody running current firmware. For stm32mp23 there is nothing to restore: ST's OP-TEE supports stm32mp21 and stm32mp23 only since 4.0.0-stm32mp, so 0xb200005a never matched any stm32mp23 firmware. About the boards: arm_wdt is enabled on all eight. - stm32mp215f-dk is not affected, stm32mp211.dtsi always had 0xbc000000. - stm32mp235f-dk and stm32mp23xx-dhcos-bb can only run firmware with 0xbc000000. - That leaves the stm32mp25 boards: stm32mp257f-dk, stm32mp257f-ev1, stm32mp257d-engicam-microgea-rmm, stm32mp255c-dhcos-dhsbc and stm32mp25xx-dhcos-bb. Only those still shipping a 3.19 based OP-TEE need the old ID. So I would suggest the opposite direction: keep 0xbc000000 in the SoC dtsi, which matches upstream OP-TEE and current ST firmware, and let the boards that shipped with the old firmware override it in their board dts: &arm_wdt { arm,smc-id = <0xb200005a>; }; Marek, would that work for the DHCOS boards? I can send the patch if you tell me which of them ship the old OP-TEE. Your OP-TEE change to accept both IDs is a good mitigation on top of it for anybody who updates the firmware. Best regards, Mateusz