From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received-SPF: Pass (sender SPF authorized) identity=mailfrom; client-ip=2607:f8b0:400d:c0d::230; helo=mail-qt0-x230.google.com; envelope-from=rafaelrodrigues.machado@gmail.com; receiver=edk2-devel@lists.01.org Received: from mail-qt0-x230.google.com (mail-qt0-x230.google.com [IPv6:2607:f8b0:400d:c0d::230]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id E9E85207E5401 for ; Tue, 8 May 2018 09:06:32 -0700 (PDT) Received: by mail-qt0-x230.google.com with SMTP id e8-v6so36821417qth.0 for ; Tue, 08 May 2018 09:06:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=MS0BXPBRZ5XNpXAQVDdmv3/zHAv4/CkzaCjh2rE98B4=; b=ldJPoWYqPiyhNtg0Z/KmWDHnoPj8m9+t90PRPB5XBvvYYBxp8FGgT8bYFPqxhdJNRf VXUGQaivRMKhqz7Q5/zzRWWAgCMlgoIgy81QblSfwsUFU31fajru+SVbUqJYLp/BqdmM PWAeEWeTMF6dyiXLswdoX/cC2bdU+txZDG67nYxlwc3nh5CgBwM/S4G05yUBbNYrAfNF qM8qCnPDVzDx+j9fRJnegvEJUinhl4RCpMaYn4iKWYk7cgbcS4Z28wUL4Sg9AiMqR3nn dtN6oU+EX8ju46zpidw4vaTrb0tpVLAvcYw29kf12DS4gWnxcat7o3G+vntZh6+Z9FIm FvLg== 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=MS0BXPBRZ5XNpXAQVDdmv3/zHAv4/CkzaCjh2rE98B4=; b=pzKltDMLR3GcRwV9PSIo0E+CROJOXb4HkzXH7c72qplZXyB8SnFltmMwYM4/cl/YGi lEEZsAo48/khn+F+eoN9xekjrbnDRt7/8EDs9/pCjcAGDc6hNbE13rDwTfZft7RqF1O+ pORfliVy+SazgsLpVe+a9vtFKQROvtlfDMedEp58MwFeU6brV8nVXz8DIw/I7MHeBzr1 715ocfWFMu+2yU0HKFFYgn/ZFhOvRYF9LjeV5yPHat9F1y5twZi4RDinuqAfgxIvOvVa wN1xGA1nYcD6LAPXc1NK5DiUFaomYNcORvnomlqJWAVuExFu7zm4f4BGqLfogQem5Tqy +ATw== X-Gm-Message-State: ALQs6tDottd3zDRs7yd0hcUaYaOixnQagGuzuVRQmKxcz40GEH8ZrKYd isotTIL98GsCeZO/YNxby+XT0Yzs7+y6CeroOYI= X-Google-Smtp-Source: AB8JxZrDsKLy/qJzjaATL0HagqIMPjtvSBWV7JGehC4oFb8zKzlbLwPzprxViqZxLFqDdW5pj+R2/7sRq8UascEtA5o= X-Received: by 2002:aed:2374:: with SMTP id i49-v6mr33035833qtc.412.1525795591727; Tue, 08 May 2018 09:06:31 -0700 (PDT) MIME-Version: 1.0 References: <220B682A-EFD1-4989-A9BD-6D3DEB2E3EB4@apple.com> In-Reply-To: <220B682A-EFD1-4989-A9BD-6D3DEB2E3EB4@apple.com> From: Rafael Machado Date: Tue, 08 May 2018 16:06:21 +0000 Message-ID: To: Andrew Fish Cc: "edk2-devel@lists.01.org" X-Content-Filtered-By: Mailman/MimeDel 2.1.26 Subject: Re: Empty function at BaseCacheMaintenanceLib X-BeenThere: edk2-devel@lists.01.org X-Mailman-Version: 2.1.26 Precedence: list List-Id: EDK II Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 08 May 2018 16:06:33 -0000 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Got it! Thanks for the answer Andrew. Rafael Machado Em ter, 8 de mai de 2018 =C3=A0s 12:55, Andrew Fish escre= veu: > Rafael, > > I seem to remember those functions are used to manage the cache on a > Harvard architecture caches [1]. > > If you look at InvalidateInstructionCacheRange() you will notice it is > used when code gets loaded into memory to keep the data and instruction > caches coherent. If the instruction cache maintains coherency in hardware > then there is no need for this functions to do anything. > > If you notice the IPF version actually does something, and that is why > these functions exists. > > [1] https://en.wikipedia.org/wiki/Harvard_architecture > > Thanks, > > Andrew Fish > > On May 8, 2018, at 6:46 AM, Rafael Machado < > rafaelrodrigues.machado@gmail.com> wrote: > > Hi everyone > > I have a question. During a research I got to the BaseCacheMaintenanceLib= , > and noticed that there is a function that is not implemented. > > The function InvalidateInstructionCache does not have a body, but as far = as > I > could check it's used in some places. > > Is it ok to have this function empty? > > Thanks and Regards > Rafael R. Machado > > _______________________________________________ > edk2-devel mailing list > edk2-devel@lists.01.org > https://lists.01.org/mailman/listinfo/edk2-devel > > >