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 5469AC433EF for ; Thu, 7 Apr 2022 11:58:06 +0000 (UTC) Received: from h2850616.stratoserver.net (localhost [IPv6:::1]) by phobos.denx.de (Postfix) with ESMTP id 5E73583D90; Thu, 7 Apr 2022 13:58:04 +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="iRTwxmFh"; dkim-atps=neutral Received: by phobos.denx.de (Postfix, from userid 109) id CE1C883D9F; Thu, 7 Apr 2022 13:58:01 +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 E127383D90 for ; Thu, 7 Apr 2022 13:57:58 +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 54ABA13FCA1; Thu, 7 Apr 2022 13:57:58 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=nic.cz; s=default; t=1649332678; bh=AFd8wRpfwnI5OeNlcUfon0pVeTRuzEEU+0eWMNVl15E=; h=Date:From:To:Cc:Subject:From; b=iRTwxmFhNOBtyDlCQ4JW0SRr49xHl8KI1X98E5pjCPpODvQLy7WtkB661IcOIh4yr Jz5qfYDaAgssGbUoJPg12F7JVGIRSY1GCFJOgJjQhoCGxVQE2Ez8W5qdjZW8BR41QW bC7SyDzy4MwpWJlQYqCprSgOAF+FajOdWHGNjVMs= Date: Thu, 7 Apr 2022 13:57:57 +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: <20220407135757.6e6c9544@thinkpad> In-Reply-To: <20220407115323.kfolfrjv3czdd2jg@pali> References: <20220406121818.31078-1-pali@kernel.org> <20220406212159.6eefb7b1@thinkpad> <20220407115323.kfolfrjv3czdd2jg@pali> 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 Thu, 7 Apr 2022 13:53:23 +0200 Pali Roh=C3=A1r wrote: > On Wednesday 06 April 2022 21:21:59 Marek Beh=C3=BAn wrote: > > On Wed, 6 Apr 2022 14:18:18 +0200 > > Pali Roh=C3=A1r wrote: > > =20 > > > 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 =20 > >=20 > > 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. =20 >=20 > On A385 there is errata only for programming OTP bits. >=20 > > Are the values you read always the same? Even across power cycles? > >=20 > > Marek =20 >=20 > Reading is working fine and is stable also after power cycles. Marvell > Internal Use contains data which are same after more reads. In that case Reviewed-by: Marek Beh=C3=BAn