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=-0.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no 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 B364CC54FCC for ; Tue, 21 Apr 2020 15:20:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 66B382068F for ; Tue, 21 Apr 2020 15:20:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=walle.cc header.i=@walle.cc header.b="VEkFTSh0" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726753AbgDUPUZ (ORCPT ); Tue, 21 Apr 2020 11:20:25 -0400 Received: from ssl.serverraum.org ([176.9.125.105]:37199 "EHLO ssl.serverraum.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725613AbgDUPUY (ORCPT ); Tue, 21 Apr 2020 11:20:24 -0400 Received: from ssl.serverraum.org (web.serverraum.org [172.16.0.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ssl.serverraum.org (Postfix) with ESMTPSA id CF11923059; Tue, 21 Apr 2020 17:20:22 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=walle.cc; s=mail2016061301; t=1587482423; 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=11Is5HZRKmOiZumdMUwNkL7ciOuq8bgi7k2YfmGDNpI=; b=VEkFTSh0uY4eQcKr7G1Ri0EFROHJz5Dlss5bT0wVp6+UlpFMj7EfhrU/KNDBGe3jVnJrRW MB+6ApsUEiALMQDfLtFaAb93h7SVgbovYkwATRjaIdEkKGmwwxKb8Hv0+9ExkqzN+SyXQ9 TQ8FEQM7VI/6bcfrJfHCuY9g24a4JpI= MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Tue, 21 Apr 2020 17:20:22 +0200 From: Michael Walle To: Andrew Lunn Cc: Russell King - ARM Linux admin , linux-kernel@vger.kernel.org, netdev@vger.kernel.org, Florian Fainelli , Heiner Kallweit , "David S . Miller" , Vladimir Oltean Subject: Re: [RFC PATCH net-next 1/3] net: phy: add concept of shared storage for PHYs In-Reply-To: <20200421145214.GD933345@lunn.ch> References: <20200420232624.9127-1-michael@walle.cc> <20200421143455.GB933345@lunn.ch> <20200421144302.GD25745@shell.armlinux.org.uk> <20200421145214.GD933345@lunn.ch> Message-ID: X-Sender: michael@walle.cc User-Agent: Roundcube Webmail/1.3.10 X-Spamd-Bar: + X-Rspamd-Server: web X-Rspamd-Queue-Id: CF11923059 X-Spamd-Result: default: False [1.40 / 15.00]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; FREEMAIL_ENVRCPT(0.00)[gmail.com]; TO_MATCH_ENVRCPT_ALL(0.00)[]; TAGGED_RCPT(0.00)[]; MIME_GOOD(-0.10)[text/plain]; DKIM_SIGNED(0.00)[]; RCPT_COUNT_SEVEN(0.00)[8]; NEURAL_HAM(-0.00)[-0.975]; RCVD_COUNT_ZERO(0.00)[0]; FROM_EQ_ENVFROM(0.00)[]; MIME_TRACE(0.00)[0:+]; FREEMAIL_CC(0.00)[armlinux.org.uk,vger.kernel.org,gmail.com,davemloft.net,nxp.com]; MID_RHS_MATCH_FROM(0.00)[]; SUSPICIOUS_RECIPS(1.50)[] Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am 2020-04-21 16:52, schrieb Andrew Lunn: > On Tue, Apr 21, 2020 at 03:43:02PM +0100, Russell King - ARM Linux > admin wrote: >> On Tue, Apr 21, 2020 at 04:34:55PM +0200, Andrew Lunn wrote: >> > > +static inline bool phy_package_init_once(struct phy_device *phydev) >> > > +{ >> > > + struct phy_package_shared *shared = phydev->shared; >> > > + >> > > + if (!shared) >> > > + return false; >> > > + >> > > + return !test_and_set_bit(PHY_SHARED_F_INIT_DONE, &shared->flags); >> > > +} >> > >> > I need to look at how you actually use this, but i wonder if this is >> > sufficient. Can two PHYs probe at the same time? Could we have one PHY >> > be busy setting up the global init, and the other thinks the global >> > setup is complete? So with Russells answer below, this should be clarified and the test_and_set_bit() is enough correct? >> > Do we want a comment like: 'Returns true when the >> > global package initialization is either under way or complete'? I've forgot the whole annotation here. >> IIRC, probe locking in the driver model is by per-driver locks, so >> any particular driver won't probe more than one device at a time. -michael