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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 417E2C43217 for ; Tue, 22 Nov 2022 17:55:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234075AbiKVRzI (ORCPT ); Tue, 22 Nov 2022 12:55:08 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39854 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234629AbiKVRyf (ORCPT ); Tue, 22 Nov 2022 12:54:35 -0500 Received: from relay5-d.mail.gandi.net (relay5-d.mail.gandi.net [217.70.183.197]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C8878DFE; Tue, 22 Nov 2022 09:52:36 -0800 (PST) Received: (Authenticated sender: miquel.raynal@bootlin.com) by mail.gandi.net (Postfix) with ESMTPSA id 9BF001C0004; Tue, 22 Nov 2022 17:52:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1669139555; 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=LlhTz4hZ6khVI5ivLTLmhvJIL86V0Pr/7JrsMu5aav0=; b=SMMCzrs0uEnKUmCsxVv/pVCvICUZCNmuXWZZXL23JO+6908+SKZxVrD1vJ5PGEahS1Ec7L 3jcXg8WpBne2CPMdi5l/I7JwAMrKwGpCzn2v9eeRDHPID4/v29t5XCNreDV8ZWFh55vtEa IeGzEEha0XsOXpZzsUf1PfaU6A8cM8SgQ2ca9Wl/epKakpeeGCOwMPFfcJtqn9ob3cg/Vd g3UwGMZYxk69xBvXoXb2vf4ObcCw9BK4hB0stTFZ8XkukCVFpyl3hoFeImcKW7Qj9wWeMc fVFn9KMrmkRJ7en2XXVf3rp9StoYggUdwYTrHHFOeVNIf2m7+JI9N0Q7vnzbUA== Date: Tue, 22 Nov 2022 18:52:31 +0100 From: Miquel Raynal To: Marcin Wojtas Cc: Rob Herring , Krzysztof Kozlowski , devicetree@vger.kernel.org, "David S. Miller" , Jakub Kicinski , Paolo Abeni , Eric Dumazet , netdev@vger.kernel.org, Russell King , Taras Chornyi , linux-kernel@vger.kernel.org, Robert Marko , Luka Perkov , Thomas Petazzoni , Michael Walle Subject: Re: [PATCH net-next 6/6] net: mvpp2: Consider NVMEM cells as possible MAC address source Message-ID: <20221122185231.6302874a@xps-13> In-Reply-To: References: <20221117215557.1277033-1-miquel.raynal@bootlin.com> <20221117215557.1277033-7-miquel.raynal@bootlin.com> <20221121102928.7b190296@xps-13> Organization: Bootlin X-Mailer: Claws Mail 4.0.0 (GTK+ 3.24.33; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Hi Marcin, mw@semihalf.com wrote on Mon, 21 Nov 2022 15:46:44 +0100: > pon., 21 lis 2022 o 10:29 Miquel Raynal napis= a=C5=82(a): > > > > Hi Marcin, > > > > mw@semihalf.com wrote on Sat, 19 Nov 2022 09:18:34 +0100: > > =20 > > > Hi Miquel, > > > > > > > > > czw., 17 lis 2022 o 22:56 Miquel Raynal n= apisa=C5=82(a): =20 > > > > > > > > The ONIE standard describes the organization of tlv (type-length-va= lue) > > > > arrays commonly stored within NVMEM devices on common networking > > > > hardware. > > > > > > > > Several drivers already make use of NVMEM cells for purposes like > > > > retrieving a default MAC address provided by the manufacturer. > > > > > > > > What made ONIE tables unusable so far was the fact that the informa= tion > > > > where "dynamically" located within the table depending on the > > > > manufacturer wishes, while Linux NVMEM support only allowed statica= lly > > > > defined NVMEM cells. Fortunately, this limitation was eventually ta= ckled > > > > with the introduction of discoverable cells through the use of NVMEM > > > > layouts, making it possible to extract and consistently use the con= tent > > > > of tables like ONIE's tlv arrays. > > > > > > > > Parsing this table at runtime in order to get various information i= s now > > > > possible. So, because many Marvell networking switches already foll= ow > > > > this standard, let's consider using NVMEM cells as a new valid sour= ce of > > > > information when looking for a base MAC address, which is one of the > > > > primary uses of these new fields. Indeed, manufacturers following t= he > > > > ONIE standard are encouraged to provide a default MAC address there= , so > > > > let's eventually use it if no other MAC address has been found usin= g the > > > > existing methods. > > > > > > > > Link: https://opencomputeproject.github.io/onie/design-spec/hw_requ= irements.html =20 > > > > > > Thanks for the patch. Did you manage to test in on a real HW? I am cu= rious about =20 > > > > Yes, I have a Replica switch on which the commercial ports use the > > replica PCI IP while the config "OOB" port is running with mvpp2: > > [ 16.737759] mvpp2 f2000000.ethernet eth52: Using nvmem cell mac addr= ess 18:be:92:13:9a:00 > > =20 >=20 > Nice. Do you have a DT snippet that can possibly be shared? I'd like > to recreate this locally and eventually leverage EDK2 firmware to > expose that. Yes of course, the DT is public on Sartura's Github, but here is the exact file I used showing the diff cleaning the Armada 7040 TN48M DT eeprom description and its use as an nvmem-cell provider): https://github.com/miquelraynal/linux/commit/230ee68728799454e2f07f61792e11= 724e731d6d >=20 > > > > Signed-off-by: Miquel Raynal > > > > --- > > > > drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c | 6 ++++++ > > > > 1 file changed, 6 insertions(+) > > > > > > > > diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c b/driv= ers/net/ethernet/marvell/mvpp2/mvpp2_main.c > > > > index eb0fb8128096..7c8c323f4411 100644 > > > > --- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c > > > > +++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c > > > > @@ -6104,6 +6104,12 @@ static void mvpp2_port_copy_mac_addr(struct = net_device *dev, struct mvpp2 *priv, > > > > } > > > > } > > > > > > > > + if (!of_get_mac_address(to_of_node(fwnode), hw_mac_addr)) {= =20 > > > > > > Unfortunately, nvmem cells seem to be not supported with ACPI yet, so > > > we cannot extend fwnode_get_mac_address - I think it should be, > > > however, an end solution. =20 > > > > Agreed. > > =20 > > > As of now, I'd prefer to use of_get_mac_addr_nvmem directly, to avoid > > > parsing the DT again (after fwnode_get_mac_address) and relying > > > implicitly on falling back to nvmem stuff (currently, without any > > > comment it is not obvious). =20 > > > > I did not do that in the first place because of_get_mac_addr_nvmem() > > was not exported, but I agree it would be the cleanest (and quickest) > > approach, so I'll attempt to export the function first, and then use it > > directly from the driver. > > =20 >=20 > That would be great, thank you. Please add one-comment in the > mvpp2_main.c, that this is valid for now only in DT world. Ack. Thanks, Miqu=C3=A8l