From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from relay6-d.mail.gandi.net (relay6-d.mail.gandi.net [217.70.183.198]) (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 9584960881 for ; Tue, 20 Feb 2024 10:07:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.70.183.198 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708423626; cv=none; b=Sb+rlRuufDOOuQFe86uDMFiN2gLeaiDyDsxh5avvxfGEsfx9zGatsZd0sFFROsA1yDiLBMSM54kiHTSrU+a522lHGbPY25fOkEajqXHsGOqfHhTh+b98IZfnteLHJ5pK3cuRXVWkLQB4zngdtVeQvxwser1oCInHw9gllN+JmBI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708423626; c=relaxed/simple; bh=vfsBzlvDSKZlgnd0dC5lHTjvH7sh9tVzDUOPiFEh3K4=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=e3KkhfuhtHXDVfHTOPOa8K3swg8RGs9F1ZCdxE1g6gJDtLGc4dmUmglbZKAb4fMTNuJjxMlLZhvL1t+k4V935+mU0/W3axArOJO0zK83lnjIWS2daVU/9dWJqQ2QAfdEyx+TFSClfCIpozCy1jZfXxChwcmOdMjvWYWJ+dWXa8c= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com; spf=pass smtp.mailfrom=bootlin.com; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b=RJtwup74; arc=none smtp.client-ip=217.70.183.198 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="RJtwup74" Received: by mail.gandi.net (Postfix) with ESMTPSA id 7EACEC000D; Tue, 20 Feb 2024 10:07:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1708423622; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=vfsBzlvDSKZlgnd0dC5lHTjvH7sh9tVzDUOPiFEh3K4=; b=RJtwup7441NP8SZ24w+gxrC99nCEvg7FFQzXF8A2z2zUzN+evmbndKm73xMnqJpzucoaMh UzN3yjA/dL0nMh3Rw0+EIfmE85b5/5vzqJPBXVpPTXDbF4I2JTdEIYvBW4psJHh8yShPCg +FEeqwtCb8ZaTtjwzfZBm8l9ZHlLx0/1Q78nTvqcVmEPVnN0ef00u8Jv5JEVumzZERAqA1 OunMaR2AD+LpGZKRddLdN+4cYzJqpqGOaOpA5w8cnXm7feDEvApoo9mIsnBrpvASmdVA7N 3XMIlNqSeiYAhc2IT4zhIDzK4kJkpGyyFx6Ive9z+WZUjv4d0nBvsgnbuvbS6Q== Date: Tue, 20 Feb 2024 11:07:01 +0100 From: Miquel Raynal To: Marco Felsch Cc: Michael Walle , srinivas.kandagatla@linaro.org, gregkh@linuxfoundation.org, rafal@milecki.pl, linux-kernel@vger.kernel.org, kernel@pengutronix.de Subject: Re: [RFC PATCH] nvmem: core: add sysfs cell write support Message-ID: <20240220110701.5ac88fed@xps-13> In-Reply-To: <20240220095038.2betrguygehvwodz@pengutronix.de> References: <20240215211401.1201004-1-m.felsch@pengutronix.de> <20240216100750.zxl4wncbgpulr2cc@pengutronix.de> <20240219120414.32395299@xps-13> <20240219115358.xui5fpoisvsubdyb@pengutronix.de> <20240220101811.6ae23f2e@xps-13> <20240220095038.2betrguygehvwodz@pengutronix.de> Organization: Bootlin X-Mailer: Claws Mail 4.0.0 (GTK+ 3.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-kernel@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-GND-Sasl: miquel.raynal@bootlin.com Hi Marco, > > > > Regarding UBI(FS) I'm not sure if this is required at all since you= have > > > > an filesystem. IMHO nvmem-cells are very lowelevel and are not made= for > > > > filesystem backed backends. =20 > >=20 > > I'm really talking about UBI, not UBIFS. UBI is just like MTD but > > handles wear leveling. There is a pending series for enabling nvmem > > cells on top of UBI. =20 >=20 > Cells on-top of a wear leveling device? Interesting, the cell-api is > very lowlevel which means the specified cell will be at the exact same > place on the hardware device as specified in the dts. How do you know > that with wear leveling underneath the cell-api? https://lore.kernel.org/lkml/cover.1702952891.git.daniel@makrotopia.org/ I haven't tested it though. Thanks, Miqu=C3=A8l