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 X-Spam-Level: X-Spam-Status: No, score=-5.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8A168C35249 for ; Mon, 3 Feb 2020 18:36:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6B5B92082E for ; Mon, 3 Feb 2020 18:36:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729333AbgBCSgK (ORCPT ); Mon, 3 Feb 2020 13:36:10 -0500 Received: from mx2.suse.de ([195.135.220.15]:36022 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727491AbgBCSgK (ORCPT ); Mon, 3 Feb 2020 13:36:10 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 2B527ACB1; Mon, 3 Feb 2020 18:36:05 +0000 (UTC) Message-ID: <45e138de5ddd70e8033bdef6484703eed60a9cb7.camel@suse.de> Subject: Re: [PATCH 6/6] net: bcmgenet: reduce severity of missing clock warnings From: Nicolas Saenz Julienne To: Jeremy Linton , Stefan Wahren , netdev@vger.kernel.org Cc: opendmb@gmail.com, f.fainelli@gmail.com, davem@davemloft.net, bcm-kernel-feedback-list@broadcom.com, linux-kernel@vger.kernel.org, andrew@lunn.ch, hkallweit1@gmail.com Date: Mon, 03 Feb 2020 19:36:01 +0100 In-Reply-To: <34aba1d9-5cad-0fee-038d-c5f3bfc9ed30@arm.com> References: <20200201074625.8698-1-jeremy.linton@arm.com> <20200201074625.8698-7-jeremy.linton@arm.com> <2dfd6cd2-1dd0-c8ff-8d83-aed3b4ea7a79@gmx.net> <34aba1d9-5cad-0fee-038d-c5f3bfc9ed30@arm.com> Content-Type: multipart/signed; micalg="pgp-sha256"; protocol="application/pgp-signature"; boundary="=-2GtKugds89inu65PZmZ2" User-Agent: Evolution 3.34.3 MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --=-2GtKugds89inu65PZmZ2 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Hi, BTW the patch looks good to me too: Reviewed-by: Nicolas Saenz Julienne On Sat, 2020-02-01 at 13:27 -0600, Jeremy Linton wrote: > Hi, >=20 > First, thanks for looking at this! >=20 > On 2/1/20 10:44 AM, Stefan Wahren wrote: > > Hi Jeremy, > >=20 > > [add Nicolas as BCM2835 maintainer] > >=20 > > Am 01.02.20 um 08:46 schrieb Jeremy Linton: > > > If one types "failed to get enet clock" or similar into google > > > there are ~370k hits. The vast majority are people debugging > > > problems unrelated to this adapter, or bragging about their > > > rpi's. Given that its not a fatal situation with common DT based > > > systems, lets reduce the severity so people aren't seeing failure > > > messages in everyday operation. > > >=20 > > i'm fine with your patch, since the clocks are optional according to th= e > > binding. But instead of hiding of those warning, it would be better to > > fix the root cause (missing clocks). Unfortunately i don't have the > > necessary documentation, just some answers from the RPi guys. >=20 > The DT case just added to my ammunition here :) >=20 > But really, I'm fixing an ACPI problem because the ACPI power management= =20 > methods are also responsible for managing the clocks. Which means if I= =20 > don't lower the severity (or otherwise tweak the code path) these errors= =20 > are going to happen on every ACPI boot. >=20 > > This is what i got so far: Stefan, Apart from the lack of documentation (and maybe also time), is ther= e any specific reason you didn't sent the genet clock patch yet? It should be= OK functionally isn't it? > BTW: For DT, is part of the problem here that the videocore mailbox has= =20 > a clock management method? I don't think it'll be the case for these clocks. We try to only use the mailbox interface if access to the clock is shared with videocore's firmwar= e. The only example for now is 'pllb' which drives the CPU. See clk-raspberryp= i.c for the firmware part and clk-bcm2835.c for the rest. Note that the firmware interface has some shortcomings, it isn't fine grain= ed nor provides a full clock tree to work with, also some clock changes, from videocore's point of view, might change multiple plls behind your back. See= for example the ARM clock, at offset 0x3[1]: if you don't explicitly disable tu= rbo mode, it'll change both pllb and pllc. Affecting a whole lot of peripherals= . In an Ideal world I'd love to see them implement ARM's SCMI[2]. It would ma= ke our lives easier. > For ACPI one of the paths of investigation is to write AML which just > interfaces to that mailbox interface for clock control here. (there is al= so > SCMII to be considered). As we're on the topic of integrating the mailbox interfaces with ACPI, have= you looked at VCHIQ in the staging directory? It serves as an interface to videocore for the camera, HDMI audio and video codec drivers. It ultimately depends on the mailbox interface mentioned above. It might be interesting f= or you to look into it before writing the AML interface to the mailbox. Regards, Nicolas [1] https://github.com/raspberrypi/firmware/wiki/Mailbox-property-interface [2] https://github.com/raspberrypi/firmware/issues/1139 --=-2GtKugds89inu65PZmZ2 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- iQEzBAABCAAdFiEErOkkGDHCg2EbPcGjlfZmHno8x/4FAl44aBEACgkQlfZmHno8 x/45rwf/QSRRNbEoqiSj02LaAKe+BMz+rYKuYE771m2QJ4r9C25KpfQE9Od4qm4w PralyFBM1NpW2bq3LDuavLB/fq57dgYz7wCPPt8SqV8hLHapnwUXWCot14/6KwGN RNnxr1Wrxr4ruvnOnY2zzJbT9gf8ofxIrrnKpxoUPF5OFN8XB9il9dU7ctkhYeFP NjvEJg7t4+pfxUeZ6UA6o7EEZv0sV/IgFeC/T2lzNEH0JCbcLzdyVp/7loCZqOPC 3SGTrtrVgJbHTyIcUQUq76QUNmE671NDfvekz0r1JMEp9qYjPlOw4TS7YRYd73ki XYwwIsKd2sKs9Jp+DJBmh6LNNNEiGw== =tAsH -----END PGP SIGNATURE----- --=-2GtKugds89inu65PZmZ2--