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 phobos.denx.de (phobos.denx.de [85.214.62.61]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 3A9DEC433F5 for ; Wed, 6 Apr 2022 19:22:07 +0000 (UTC) Received: from h2850616.stratoserver.net (localhost [IPv6:::1]) by phobos.denx.de (Postfix) with ESMTP id 8B77D83D2F; Wed, 6 Apr 2022 21:22:04 +0200 (CEST) Authentication-Results: phobos.denx.de; dmarc=pass (p=quarantine dis=none) header.from=nic.cz Authentication-Results: phobos.denx.de; spf=pass smtp.mailfrom=u-boot-bounces@lists.denx.de Authentication-Results: phobos.denx.de; dkim=pass (1024-bit key; secure) header.d=nic.cz header.i=@nic.cz header.b="IF/ZrkQX"; dkim-atps=neutral Received: by phobos.denx.de (Postfix, from userid 109) id 0245F83D05; Wed, 6 Apr 2022 21:22:03 +0200 (CEST) Received: from mail.nic.cz (mail.nic.cz [217.31.204.67]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by phobos.denx.de (Postfix) with ESMTPS id 5869483D2F for ; Wed, 6 Apr 2022 21:22:00 +0200 (CEST) Authentication-Results: phobos.denx.de; dmarc=pass (p=quarantine dis=none) header.from=nic.cz Authentication-Results: phobos.denx.de; spf=pass smtp.mailfrom=marek.behun@nic.cz Received: from thinkpad (unknown [172.20.6.87]) by mail.nic.cz (Postfix) with ESMTPS id C720613F62D; Wed, 6 Apr 2022 21:21:59 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=nic.cz; s=default; t=1649272919; bh=E0cJ9oq75rFh2MpVV5iEOQkF8WaQyL0cNanOPVhfLxU=; h=Date:From:To:Cc:Subject:From; b=IF/ZrkQXDmfxcCsERit1qZ93PMOsCm0FJmkh4U3YRCbbWRS2Nto6skDiA3ZFr0IV0 0Ms0f3QugmIs2GCybXs4RHjPm5ikTNRi/vsKPeE2MNw1aIMl+O6AJJx+Jq3+dR+DY5 wM1XAbpECI1l96JMis6MSAbmCZVOHASHVXq1zpeM= Date: Wed, 6 Apr 2022 21:21:59 +0200 From: Marek =?UTF-8?B?QmVow7pu?= To: Pali =?UTF-8?B?Um9ow6Fy?= Cc: Stefan Roese , u-boot@lists.denx.de Subject: Re: [PATCH] arm: mvebu: Add support for reading LD0 and LD1 eFuse Message-ID: <20220406212159.6eefb7b1@thinkpad> In-Reply-To: <20220406121818.31078-1-pali@kernel.org> References: <20220406121818.31078-1-pali@kernel.org> X-Mailer: Claws Mail 3.18.0 (GTK+ 2.24.33; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-BeenThere: u-boot@lists.denx.de X-Mailman-Version: 2.1.39 Precedence: list List-Id: U-Boot discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: u-boot-bounces@lists.denx.de Sender: "U-Boot" X-Virus-Scanned: clamav-milter 0.103.5 at phobos.denx.de X-Virus-Status: Clean On Wed, 6 Apr 2022 14:18:18 +0200 Pali Roh=C3=A1r wrote: > Armada 385 contains 64 lines of HD eFuse and 2 lines of LD eFuse. HD eFuse > is used for secure boot and each line is 64 bits long + 1 lock bit. LD > eFuse lines are 256 bits long + 1 lock bit. LD 0 line is reserved for > Marvell Internal Use and LD 1 line is for General Purpose Data. U-Boot > already contains HD eFuse reading and programming support. >=20 > This patch implements LD eFuse reading support. LD 0 line is mapped to > U-Boot fuse bank 64 and LD 1 line to fuse bank 65. >=20 > LD 0 Marvell Internal Use line seems that was burned in factory with some > data and can be read by U-Boot fuse command: >=20 > =3D> fuse read 64 0 9 =20 >=20 > LD 1 General Purpose Data line is by default empty and can be read by > U-Boot fuse command: >=20 > =3D> fuse read 65 0 9 =20 >=20 > Signed-off-by: Pali Roh=C3=A1r I am not sure whether this can be used safely on Turris Omnia - there was some issue with voltage or something, I know for sure that burning does not work on Omnia, but I am not sure if the issue also prevents stable reading. Are the values you read always the same? Even across power cycles? Marek