From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lithops.sigma-star.at (lithops.sigma-star.at [195.201.40.130]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0C44D1B959; Sun, 25 Feb 2024 22:12:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=195.201.40.130 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708899181; cv=none; b=ZtkDHX+KVC4Gknr9sD5+V6nnk96c4/cmKtBXMZIynd8zBdVWdG0A9SLBgFINumBKK9JRiOHK/9v9y3+nVAyQkf/2IcRWhAB5/lW3448MNBGSMuvKb7NKgl2NPncgRCfDk2TCyGhhvzIXe52MeQhYGf+h/QPrKuHJZ3gNzBLOnwU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708899181; c=relaxed/simple; bh=R3PowNmV6z7V5+4rKOYfRZaysNd/F1B+PjegZMDewpo=; h=Date:From:To:Cc:Message-ID:In-Reply-To:References:Subject: MIME-Version:Content-Type; b=tRGSyCM0JSzhMpXG+o5D8ZAM0jbg5cXhmCH0mRCZErJAqLRGHf7rJLHSdfjhQTWB/+d9XvxqsECw9c9U1Wr7eDS7Ar0Wqbr0DL1WZDHIsN/kYyYVf2DgxJHdZYts2SW/MwAXZKjFk3++m2Ef3UQT0SsuEFcucrUoGIF6jGoTm+E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=nod.at; spf=fail smtp.mailfrom=nod.at; arc=none smtp.client-ip=195.201.40.130 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=nod.at Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=nod.at Received: from localhost (localhost [127.0.0.1]) by lithops.sigma-star.at (Postfix) with ESMTP id 7FFD36342D4C; Sun, 25 Feb 2024 23:12:55 +0100 (CET) Received: from lithops.sigma-star.at ([127.0.0.1]) by localhost (lithops.sigma-star.at [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id ZLfvZ-sQLlLK; Sun, 25 Feb 2024 23:12:54 +0100 (CET) Received: from localhost (localhost [127.0.0.1]) by lithops.sigma-star.at (Postfix) with ESMTP id A73D46340E18; Sun, 25 Feb 2024 23:12:54 +0100 (CET) Received: from lithops.sigma-star.at ([127.0.0.1]) by localhost (lithops.sigma-star.at [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id DkOwGdRYt7b1; Sun, 25 Feb 2024 23:12:54 +0100 (CET) Received: from lithops.sigma-star.at (lithops.sigma-star.at [195.201.40.130]) by lithops.sigma-star.at (Postfix) with ESMTP id 7DB686343B4B; Sun, 25 Feb 2024 23:12:54 +0100 (CET) Date: Sun, 25 Feb 2024 23:12:54 +0100 (CET) From: Richard Weinberger To: Miquel Raynal , Daniel Golle Cc: Vignesh Raghavendra , Rob Herring , Krzysztof Kozlowski , Conor Dooley , linux-mtd , devicetree , linux-kernel Message-ID: <1209094181.98490.1708899174329.JavaMail.zimbra@nod.at> In-Reply-To: <20240219120156.383a1427@xps-13> References: <82ceb13954f7e701bf47c112333e7b15a57fc360.1702952891.git.daniel@makrotopia.org> <20240219120156.383a1427@xps-13> Subject: Re: [PATCH v7 7/7] mtd: ubi: provide NVMEM layer over UBI volumes Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Mailer: Zimbra 8.8.12_GA_3807 (ZimbraWebClient - FF97 (Linux)/8.8.12_GA_3809) Thread-Topic: provide NVMEM layer over UBI volumes Thread-Index: LhVCT6G++U013VIiCZmvxnpZEu2GqQ== ----- Urspr=C3=BCngliche Mail ----- > Von: "Miquel Raynal" > An: "Daniel Golle" > CC: "richard" , "Vignesh Raghavendra" , = "Rob Herring" , "Krzysztof > Kozlowski" , "Conor Dooley" , "linux-mtd" > , "devicetree" , "linux-kernel" > > Gesendet: Montag, 19. Februar 2024 12:01:56 > Betreff: Re: [PATCH v7 7/7] mtd: ubi: provide NVMEM layer over UBI volume= s > Hi Daniel, >=20 > daniel@makrotopia.org wrote on Tue, 19 Dec 2023 02:33:48 +0000: >=20 >> In an ideal world we would like UBI to be used where ever possible on a >> NAND chip. And with UBI support in ARM Trusted Firmware and U-Boot it >> is possible to achieve an (almost-)all-UBI flash layout. Hence the need >> for a way to also use UBI volumes to store board-level constants, such >> as MAC addresses and calibration data of wireless interfaces. >>=20 >> Add UBI volume NVMEM driver module exposing UBI volumes as NVMEM >> providers. Allow UBI devices to have a "volumes" firmware subnode with >> volumes which may be compatible with "nvmem-cells". >> Access to UBI volumes via the NVMEM interface at this point is >> read-only, and it is slow, opening and closing the UBI volume for each >> access due to limitations of the NVMEM provider API. >=20 > I don't feel qualified enough to review the other patches, however this > one looks good to me. Finally(!), I had enough time to look. Thanks for addressing all my comments form the previous series. Patches applied. I have only one tiny request, can you share the lockdep spalt you encountered in ubi_notify_add() regarding mtd_table_mutex and ubi_devices_mutex? The solutions looks okay to me, but if you have more details that would be great. Thanks, //richard