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=-3.8 required=3.0 tests=BAYES_00, 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 76B16C433B4 for ; Tue, 13 Apr 2021 12:53:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4B97561369 for ; Tue, 13 Apr 2021 12:53:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345905AbhDMMxh (ORCPT ); Tue, 13 Apr 2021 08:53:37 -0400 Received: from vps0.lunn.ch ([185.16.172.187]:48200 "EHLO vps0.lunn.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240321AbhDMMxb (ORCPT ); Tue, 13 Apr 2021 08:53:31 -0400 Received: from andrew by vps0.lunn.ch with local (Exim 4.94) (envelope-from ) id 1lWIXL-00GTYv-RL; Tue, 13 Apr 2021 14:52:59 +0200 Date: Tue, 13 Apr 2021 14:52:59 +0200 From: Andrew Lunn To: Marc Zyngier Cc: DENG Qingfang , "David S. Miller" , Florian Fainelli , Heiner Kallweit , Jakub Kicinski , Landen Chao , Matthias Brugger , Russell King , Sean Wang , Vivien Didelot , Vladimir Oltean , Rob Herring , Linus Walleij , Greg Kroah-Hartman , Sergio Paracuellos , linux-kernel@vger.kernel.org, linux-mediatek@lists.infradead.org, linux-staging@lists.linux.dev, devicetree@vger.kernel.org, netdev@vger.kernel.org, Weijie Gao , Chuanhong Guo , =?iso-8859-1?Q?Ren=E9?= van Dorst , Frank Wunderlich , Thomas Gleixner , Greg Ungerer Subject: Re: [RFC v4 net-next 2/4] net: dsa: mt7530: add interrupt support Message-ID: References: <20210412034237.2473017-1-dqfext@gmail.com> <20210412034237.2473017-3-dqfext@gmail.com> <87fszvoqvb.wl-maz@kernel.org> <20210412152210.929733-1-dqfext@gmail.com> <8735vuobfo.wl-maz@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <8735vuobfo.wl-maz@kernel.org> Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org > I guess this is depends whether the most usual case is to have all > these interrupts being actively in use or not. Most interrupts only > use a limited portion of their interrupt space at any given time. > Allocating all interrupts and creating mappings upfront is a waste of > memory. > > If the use case here is that all these interrupts will be wired and > used in most cases, then upfront allocation is probably not a problem. Hi Marc The interrupts are generally used. Since this is an Ethernet switch, generally the port is administratively up, even if there is no cable plugged in. Once/if a cable is plugged in and there is a link peer, the PHY will interrupt to indicate this. The only real case i can think of when the interrupts are not used is when the switch has more ports than connected to the front panel. This can happen in industrial settings, but not SOHO. Those ports which don't go anywhere are never configured up and so the interrupt is never used. Andrew