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=-9.0 required=3.0 tests=BAYES_00,INCLUDES_CR_TRAILER, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 07122C11F66 for ; Wed, 14 Jul 2021 13:51:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CEE8E613C5 for ; Wed, 14 Jul 2021 13:51:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231543AbhGNNx6 (ORCPT ); Wed, 14 Jul 2021 09:53:58 -0400 Received: from mail-io1-f42.google.com ([209.85.166.42]:36748 "EHLO mail-io1-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231478AbhGNNx6 (ORCPT ); Wed, 14 Jul 2021 09:53:58 -0400 Received: by mail-io1-f42.google.com with SMTP id u7so2157452ion.3; Wed, 14 Jul 2021 06:51:06 -0700 (PDT) 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=50++kkpNpej8/NTD9q8DshcKL4G56n58bwfZ59/K0OU=; b=GX3mMdEKxQV1DYNgjzcnv9mWui8dFHR6+5ZKd0ZfPz8RSjmWnWhw+cI3Gue3hoTgYS 13sZA7QAWbx819BCMBFonHvTW85FZb1YX+lk7lczQvYQ7egEe6ry5VVUYhGPjMVdGApu vD94vFMCv4iw5Pb9EqdZvFkdTnEsJpQQ24z0rn76SLk1qSZf0MDfZavPZxjD8g36a6Mf OnkaVUL2AfN80o/FmySEVgoJ4ZL99CdrMG8zvlJhAtBG4bUT6DVJmYQwzgxlS3k9zLyG xhfGQYwj0KDWsKg5SorLVdfkmwPJqto0LCLdKRP1JtcMBEg9FYowmJrfBgh6OSyQAvQr tI2w== X-Gm-Message-State: AOAM530CEAeT6v7HfV0AJ+rSvUO9imIR9KYEeKy1MczsVD5hv409g/RK 7Rz1K1KxzAJETGNT92iwjw== X-Google-Smtp-Source: ABdhPJz5/RWe5S4IxADEtcsCGrwyKwDJjXmmQQVnQ78apEZMiVvJE4pVvZlqoWl7Or2AdYCn9IOTUQ== X-Received: by 2002:a02:7093:: with SMTP id f141mr8988326jac.24.1626270666077; Wed, 14 Jul 2021 06:51:06 -0700 (PDT) Received: from robh.at.kernel.org ([64.188.179.248]) by smtp.gmail.com with ESMTPSA id s2sm1323967ilq.45.2021.07.14.06.51.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 14 Jul 2021 06:51:05 -0700 (PDT) Received: (nullmailer pid 2459772 invoked by uid 1000); Wed, 14 Jul 2021 13:51:01 -0000 Date: Wed, 14 Jul 2021 07:51:01 -0600 From: Rob Herring To: Geert Uytterhoeven Cc: Russell King , Nicolas Pitre , Ard Biesheuvel , Linus Walleij , Catalin Marinas , Will Deacon , Nick Kossifidis , Paul Walmsley , Palmer Dabbelt , Albert Ou , Frank Rowand , Dave Young , Mike Rapoport , Baoquan He , Vivek Goyal , Andrew Morton , devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-riscv@lists.infradead.org, kexec@lists.infradead.org, linux-mm@kvack.org, linux-renesas-soc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v4 02/10] memblock: Add variables for usable memory limitation Message-ID: <20210714135101.GB2441138@robh.at.kernel.org> References: <04c4d231fb03a3810d72a45c8a5bc2272c5975f3.1626266516.git.geert+renesas@glider.be> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <04c4d231fb03a3810d72a45c8a5bc2272c5975f3.1626266516.git.geert+renesas@glider.be> Precedence: bulk List-ID: X-Mailing-List: linux-renesas-soc@vger.kernel.org On Wed, Jul 14, 2021 at 02:50:12PM +0200, Geert Uytterhoeven wrote: > Add two global variables (cap_mem_addr and cap_mem_size) for storing a > base address and size, describing a limited region in which memory may > be considered available for use by the kernel. If enabled, memory > outside of this range is not available for use. > > These variables can by filled by firmware-specific code, and used in > calls to memblock_cap_memory_range() by architecture-specific code. > An example user is the parser of the "linux,usable-memory-range" > property in the DT "/chosen" node. > > Signed-off-by: Geert Uytterhoeven > --- > This is similar to how the initial ramdisk (phys_initrd_{start,size}) > and ELF core headers (elfcorehdr_{addr,size})) are handled. > > Does there exist a suitable place in the common memblock code to call > "memblock_cap_memory_range(cap_mem_addr, cap_mem_size)", or does this > have to be done in architecture-specific code? Can't you just call it from early_init_dt_scan_usablemem? If the property is present, you want to call it. If the property is not present, nothing happens. Rob