From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.3ffe.de (0001.3ffe.de [159.69.201.130]) (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 EF4A21C84A5; Thu, 6 Mar 2025 07:41:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=159.69.201.130 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741246883; cv=none; b=eXW0/FqzT3oSFuzjkwWYB9bZ/8ZYQW/tNqtO9xssFiBFMHc3j5HTqz5kpmim9BI6/ObZBg4+H6HiFleyTwXteKg/r1ApxVHLg6rQmIyY8al7yUY/Ra5Wp7bL41uFl+4GUgKAPeFmyoI5v321yh/NkBxiD1VqPfu8CJ27Q6NLSjI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741246883; c=relaxed/simple; bh=tynbRCJNvJhi67ydy0W9gjWps9spqKy6/S2sdJUz3bA=; h=Mime-Version:Content-Type:Date:Message-Id:Cc:From:To:Subject: References:In-Reply-To; b=vB2Q4ibrCTlL+9vwjsYcyaILN4yPanGJai81zuGjKtQxRT2LOb5RkD8swOasD/Yjk9ysHjApdj2UvlZK+2E7I8FLmPjiD8HvXTl78539aYlDyRbFdEA+Co3ks8FRxs+EDXYYFnlijpDSxIH5M06xFqwwgkUBkYR+1R8Y5XbFKNw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=kernel.org; spf=pass smtp.mailfrom=walle.cc; arc=none smtp.client-ip=159.69.201.130 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=kernel.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=walle.cc Received: from localhost (unknown [IPv6:2a02:810b:4320:1000:4685:ff:fe12:5967]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mail.3ffe.de (Postfix) with ESMTPSA id A0115287; Thu, 6 Mar 2025 08:41:17 +0100 (CET) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=UTF-8 Date: Thu, 06 Mar 2025 08:41:17 +0100 Message-Id: Cc: , , , , , , , , , , , , , , From: "Michael Walle" To: , Subject: Re: [PATCH 1/2] mtd: spi-nor: sst: register SFDP region into NVMEM framework to read MAC Address X-Mailer: aerc 0.16.0 References: <20250305100134.1171124-1-manikandan.m@microchip.com> <87ikonydym.fsf@bootlin.com> <84b1def7-fba7-4f29-a49b-d117efe26d26@microchip.com> In-Reply-To: <84b1def7-fba7-4f29-a49b-d117efe26d26@microchip.com> Hi, > >> From: Varshini Rajendran > >> > >> EUI identifier and the MAC Address of the Ethernet Interface is stored > >> after the SFDP table of contents starting at address 0x260 in the > >> QSPI memory. > >> Register the entire SFDP region read by the spi-nor (nor->sfdp) into t= he > >> NVMEM framework and read the MAC Address when requested using the nvme= m > >> properties in the DT by the net drivers. > >> > >> In kernel the Ethernet MAC address relied on U-Boot env variables or > >> generated a random address, which posed challenges for boards without > >> on-board EEPROMs or with multiple Ethernet ports. > >> This change ensures consistent and reliable MAC address retrieval from= QSPI, > >> benefiting boards like the sama5d29 curiosity and sam9x75 curiosity. > >=20 > > Do you mean spi-nor have a programmable area in their SFDP table? Isn't > > this supposed to be a read-only area written once in factory? > >=20 > The SST26VF064BEUI serial quad flash memory is programmed at the factory= =20 > with a globally unique address stored in the SFDP vendor > parameter table and it is permanently write-protected. Why didn't you mention that this is a vendor table in the commit message? Anyway, please write proper support in the core for parsing vendor tables and exposing them as a nvmem device if needed (and asked to do so by the driver of course). -michael