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,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED 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 6631CC432BE for ; Wed, 28 Jul 2021 20:14:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 46DBA6054F for ; Wed, 28 Jul 2021 20:14:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231312AbhG1UO0 (ORCPT ); Wed, 28 Jul 2021 16:14:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34194 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230526AbhG1UOZ (ORCPT ); Wed, 28 Jul 2021 16:14:25 -0400 Received: from mail-io1-xd2d.google.com (mail-io1-xd2d.google.com [IPv6:2607:f8b0:4864:20::d2d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E865CC061757 for ; Wed, 28 Jul 2021 13:14:23 -0700 (PDT) Received: by mail-io1-xd2d.google.com with SMTP id y200so4283881iof.1 for ; Wed, 28 Jul 2021 13:14:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=engleder-embedded-com.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=ubJgrDNEMsCflqG4YOXZKMLlAzg0rRahHfeJ5NprhF4=; b=AUo6FFwz913kDcN1mpv6AVTcXif3PDz/6RQZXRMSov+XphL+u5wIBnKUG/Lg0GF14A LjWbd11MNhh3GEwvrf8gmBxImE+rzhg4WKpI+MQqE6Ccv/0jdOK5E7CDPeY3MQHFsBTv KQt7HGf8sQNcsOZcbXlXJ2ESxsxHdwzj5V6vqhmHdDGOOejzTSmh0Hgt94rqV6cB7vQM jBt6dkzL/xg0bk0MXWlfFSdiK6PotnaMpmZ6Dp0OEgHfxNOMEBCnJw9wIzfAkPaPFV0x WYu7PIdYykbV5F4IJfTeA3R0I0pTfUs0YZMCZOGOy8fGCBRV7YLTuJjZ3+K3VPRXkwVK r9Nw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=ubJgrDNEMsCflqG4YOXZKMLlAzg0rRahHfeJ5NprhF4=; b=gnlog459VgggXiXmc92R1imrM6Mlx60TmkeaXAFb+C0LNhVQUsHRVARmieMRzI1ZGN SikN5oTWdlf6KgSA092wDueyDy+6UpK4wj58kNtVMieeC4Q2LkvUlj7UFxG0xz5sNYXu bW2rJp/TCjPQusyseuCum0HYtT8dNzoMHqqJ6uFislpFI0QARbs32poAbnCUqE1CGfCo 13M/i0bRIuXPmKwKv4n3SZ1OavcTuBMfV/j29V6vM0Xd95TsNmao6WbnqFQVx200IaLs uB0JiJSCrWveq2cI2gVrp2lWFFSwWQybS9M6hhiwF5ffUVrMipaxFZxFLRJXfi0TLz7Q ND/A== X-Gm-Message-State: AOAM5302SkNwU43yj5/73R4GMs0pz0a1NW4fhuBkq5SJj46uAQpcJTUk XO6C9GwI6stCAcQ+dfKPpgfD1c0pHgUph5mw82SGrg== X-Google-Smtp-Source: ABdhPJxzqdXkxuX25EnHM978DCQhthOlj+NIH/N6KcP4+iZ2prrC914LGZnIHH2uvlZ2pl+4CvlQWWbP61r6zbicC4M= X-Received: by 2002:a05:6638:538:: with SMTP id j24mr1293839jar.59.1627503263335; Wed, 28 Jul 2021 13:14:23 -0700 (PDT) MIME-Version: 1.0 References: <20210726194603.14671-1-gerhard@engleder-embedded.com> <20210726194603.14671-3-gerhard@engleder-embedded.com> In-Reply-To: From: Gerhard Engleder Date: Wed, 28 Jul 2021 22:14:12 +0200 Message-ID: Subject: Re: [PATCH net-next 2/5] dt-bindings: net: Add tsnep Ethernet controller To: Michal Simek Cc: Rob Herring , David Miller , Jakub Kicinski , netdev , devicetree@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Wed, Jul 28, 2021 at 12:55 PM Michal Simek wrote: > >>>>>> + - enum: > >>>>>> + - engleder,tsnep > >>>>> > >>>>> tsnep is pretty generic. Only 1 version ever? Or differences are/will > >>>>> be discoverable by other means. > >>>> > >>>> Differences shall be detected by flags in the registers; e.g., a flag for > >>>> gate control support. Anyway a version may make sense. Can you > >>>> point to a good reference binding with versions? I did not find a > >>>> network controller binding with versions. > >>> > >>> Some of the SiFive IP blocks have versions. Version numbers are the > >>> exception though. Ideally they would correspond to some version of > >>> your FPGA image. I just don't want to see 'v1' because that sounds > >>> made up. The above string can mean 'v1' or whatever version you want. > >>> I'm fine if you just add some description here about feature flag > >>> registers. > >> > >> Don't Xilinx design tool (vivado) force you to use IP version? > >> Normally all Xilinx IPs have certain version because that's the only way > >> how to manage it. > > > > Yes I use an IP version in the Xilinx design tool. I use it as a version of the > > VHDL code itself. In my case this version is not related to the > > hardware software > > interface. The goal is to keep the hardware software interface compatible, so > > the IP version should not be relevant. > > I expect this is goal for everybody but it fails over time. We normally > compose compatible string for PL based IP with IP version which is used. > And it is quite common that couple of HW version are SW compatible to > each other. > It means use the same HW version as you use now. When you reach the > point when your HW IP needs to be upgraded and will require SW alignment > you have versions around which can be used directly. I would like to follow the argument from Rob: "The above string can mean 'v1' or whatever version you want." If there ever is an incompatible new IP version, then a new compatible string can be added which means 'v2'. E.g. for 128bit physical address support I would choose the compatible string 'engleder,tsnep128'. I don't see an advantage in adding a version number to the compatible string. This IP will be used in products where compatible hardware is a must. An IP upgrade which requires SW alignment will result in heavy complaints from the customers. Such an IP upgrade would result in a new IP. Like for shared libraries, an incompatible API change is similar to a new library. Gerhard