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 1E686C433E6 for ; Mon, 8 Feb 2021 23:12:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D426964E99 for ; Mon, 8 Feb 2021 23:12:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229623AbhBHXMe (ORCPT ); Mon, 8 Feb 2021 18:12:34 -0500 Received: from mail-wr1-f44.google.com ([209.85.221.44]:41681 "EHLO mail-wr1-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229615AbhBHXMc (ORCPT ); Mon, 8 Feb 2021 18:12:32 -0500 Received: by mail-wr1-f44.google.com with SMTP id n6so6380398wrv.8; Mon, 08 Feb 2021 15:12:16 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=bv0dTMtA9ppfQnSKtZdpg4E99WwWlpYYeDwveeo27y0=; b=LxDhnEcW8JWPlMYcFv7GH87onKgr1WqKMp5INUtY7U7zbwD1m09GasFSgnZIYbl8Vc yQ4QfJuI4+eznvMNeBlaLRMUTba8wOGkVd0GA28EyzssOTcy0dW7aA1/Wvbe8fvk+HBc 1orxsvh08OC1kRlR4EeRW8EHyS1xIPUPQJSbjKjkcIgYQ+DSTInl2d3k2mYwe4GDSdgH gl+BH12WeaZ4M51VF0ZLLI/6J52Sl+Ru/jLBk6TepgKrIU0cGWTrxHkFryLKXlHn5iGh wPjznBo8nuVxfREuUhOooeb3xRhqd1XLdXuW10dy7gynuFuamquH7NvCqryDAX1K0g7n ihPA== X-Gm-Message-State: AOAM533e22YuGfBJc/Vp7kzDgFH21OMHXfzNn2y/BmGTbBx4JgTSrEAa ybrebFDDn/yNfXA+PaQeGWgouJTjfsRCPJgi X-Google-Smtp-Source: ABdhPJw6d4JBqgH/iMVqIVlgRbPTrlG64dTk/g4NiWLR01STGosEAkq245Tx8wPcoH9hNahYyOke9w== X-Received: by 2002:a5d:544b:: with SMTP id w11mr22702202wrv.1.1612825910658; Mon, 08 Feb 2021 15:11:50 -0800 (PST) Received: from rocinante ([95.155.85.46]) by smtp.gmail.com with ESMTPSA id z63sm1255067wme.8.2021.02.08.15.11.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 08 Feb 2021 15:11:50 -0800 (PST) Date: Tue, 9 Feb 2021 00:11:48 +0100 From: Krzysztof =?utf-8?Q?Wilczy=C5=84ski?= To: Gustavo Pimentel Cc: "linux-doc@vger.kernel.org" , "linux-pci@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Derek Kiernan , Dragan Cvetic , Arnd Bergmann , Andrew Morton , Greg Kroah-Hartman , Jonathan Corbet Subject: Re: [RESEND v4 4/6] Documentation: misc-devices: Add Documentation for dw-xdata-pcie driver Message-ID: References: <2cc3a3a324d299a096f1d3e682b2039d3537b013.1612390291.git.gustavo.pimentel@synopsys.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Hi Gustavo, [...] > > When I do the following: > > > > # echo 1 > /sys/kernel/dw-xdata-pcie/write > > # echo 1 > /sys/kernel/dw-xdata-pcie/stop > > # cat /sys/kernel/dw-xdata-pcie/write > > > > Would output from cat above simply show "0 MB/s" then? I wonder how > > someone using this new driver could tell whether "write" or "read" > > traffic generation has been enabled aside of reading the sysfs files, > > would adding "/sys/kernel/dw-xdata-pcie/active" be an overkill here? > > > > What do you think? > > Yes, it would display 0 MB/s. This driver is to be used mainly by the > Synopsys DesignWare HW prototyping team. I don't think the general public > will be interested or can use this driver, because requires a special HW > block available only for this prototype. Got it. > I tried to reduce to the minimal the interfaces, to avoid possible > confusion. For instance, even the /sys/kernel/dw-xdata-pcie/stop > interface could be avoided, because on the driver unloading or changing > the between write or read it calls the stop procedure. Oh, OK. > Due to the nature of the HW block, it only can allow the write or the > read at some given moment, therefore based on the last command enable > write or read, we know which mode is this driving working. > This driver will be used by the testing team on their automation scripts, > thus they will know exactly the sequence input. > > Anyway, thanks for your feedback. Thank you for taking the time to add more details for me. Much appreciated. Krzysztof