From patchwork Mon Oct 17 15:49:56 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Patrick Delaunay X-Patchwork-Id: 13008999 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 A633AC4332F for ; Mon, 17 Oct 2022 15:52:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:CC:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=9FwaQeF99G9j9zEOCCfpE6ilrGhmv8na1rL50LIsp9Y=; b=pmc77n21BJsPFB lCssNlD0sEi/89cmZj9nP6tKk+4PdlHkXwU9U6upIzPDJtcTUriMPXx+OqjQwg1yhFPgak3Cm3+/X gMMY959osYTvwXWUtEUc7Ay7b8T7iw2ZFoGSmYkJFR5vigqhzo0k2cMKyGmRcC72ODVkJrNTy76Vw mmfP1q2AAOPH+UcGczwPg3hoTOtHsK99NtomhN/x2Tn8Pibe88edyF3q0qjaxfwu96BK7AEkrSh5/ UdXxojlrSmXRpRFMgHMAC0U6EetmvcDSHmVpZo7jsYadiVi5pot/wGlnydiD60uInPW9jdW4Or4Lu CXE4nz3MpCsLGDGshoaw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1okSOW-00DTXa-KK; Mon, 17 Oct 2022 15:51:12 +0000 Received: from mx08-00178001.pphosted.com ([91.207.212.93] helo=mx07-00178001.pphosted.com) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1okSO6-00DSwW-Aj for linux-arm-kernel@lists.infradead.org; Mon, 17 Oct 2022 15:50:48 +0000 Received: from pps.filterd (m0046661.ppops.net [127.0.0.1]) by mx07-00178001.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 29HEnXPi031465; Mon, 17 Oct 2022 17:50:43 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=foss.st.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding : content-type; s=selector1; bh=phlzu4FsLYCgo+33k55masOClxFOICgga//eKhVT5DA=; b=m0kBsPwO7CE8y2TIS764D0+CDjpFLbruiUt5BdWM/Y+5Qa6z8so8W7gWR8xiunow8D/2 Ag3MKDsbAGZK/mY32jTN+NytkpII29vKQ6mQ5exp3vsgT/rkKIMLluW571BGiBb8N+cs 6jcYfXL3toxjYhrwSxp85jYYJQJPaggP2Y1OfdRpBNSDsPZ5n0grj9yNfgYzK96TeQ9Y AeMZ1BN0gLKokbG3J3Odh5dbCZTQy/ayv1Z/SkTNTRLZX2vhALBbS77hM9Y94gaDlw62 GMNuMEfZLEKwOJuaCg4Ndpi9p8IE5gl80CX3OLRPrsnMECb4LY8Qzh97z0r3H8hEbtop aQ== Received: from beta.dmz-eu.st.com (beta.dmz-eu.st.com [164.129.1.35]) by mx07-00178001.pphosted.com (PPS) with ESMTPS id 3k7krjnsh8-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 17 Oct 2022 17:50:43 +0200 Received: from euls16034.sgp.st.com (euls16034.sgp.st.com [10.75.44.20]) by beta.dmz-eu.st.com (STMicroelectronics) with ESMTP id F230210002A; Mon, 17 Oct 2022 17:50:38 +0200 (CEST) Received: from Webmail-eu.st.com (shfdag1node3.st.com [10.75.129.71]) by euls16034.sgp.st.com (STMicroelectronics) with ESMTP id ED63723C6A0; Mon, 17 Oct 2022 17:50:38 +0200 (CEST) Received: from localhost (10.75.127.120) by SHFDAG1NODE3.st.com (10.75.129.71) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256) id 15.1.2375.31; Mon, 17 Oct 2022 17:50:38 +0200 From: Patrick Delaunay To: Srinivas Kandagatla , Maxime Coquelin , Alexandre Torgue CC: Patrick Delaunay , , , Subject: [PATCH v2 2/3] nvmem: stm32: add warning when upper OTPs are updated Date: Mon, 17 Oct 2022 17:49:56 +0200 Message-ID: <20221017174953.v2.2.Ifa806ff30d7c669ba9a3df9c6b64698a2dcc073a@changeid> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20221017154957.277120-1-patrick.delaunay@foss.st.com> References: <20221017154957.277120-1-patrick.delaunay@foss.st.com> MIME-Version: 1.0 X-Originating-IP: [10.75.127.120] X-ClientProxiedBy: GPXDAG2NODE4.st.com (10.75.127.68) To SHFDAG1NODE3.st.com (10.75.129.71) X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.895,Hydra:6.0.545,FMLib:17.11.122.1 definitions=2022-10-17_13,2022-10-17_02,2022-06-22_01 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221017_085046_685351_289B3422 X-CRM114-Status: GOOD ( 15.80 ) 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: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org As the upper OTPs are ECC protected, they support only one 32 bits word programming. For a second modification of this word, these ECC become invalid and this OTP will be no more accessible, the shadowed value is invalid. This patch adds a warning to indicate an upper OTP update, because this operation is dangerous as OTP is not locked by the driver after the first update to avoid a second update. Signed-off-by: Patrick Delaunay --- (no changes since v1) drivers/nvmem/stm32-romem.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/nvmem/stm32-romem.c b/drivers/nvmem/stm32-romem.c index d93baee01d7b..bb8aa72ba2f9 100644 --- a/drivers/nvmem/stm32-romem.c +++ b/drivers/nvmem/stm32-romem.c @@ -132,6 +132,9 @@ static int stm32_bsec_write(void *context, unsigned int offset, void *buf, } } + if (offset + bytes >= priv->lower * 4) + dev_warn(dev, "Update of upper OTPs with ECC protection (word programming, only once)\n"); + return 0; }