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=-6.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS 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 69114C43331 for ; Thu, 26 Mar 2020 06:22:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3889720772 for ; Thu, 26 Mar 2020 06:22:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=brainfault-org.20150623.gappssmtp.com header.i=@brainfault-org.20150623.gappssmtp.com header.b="cp6ZDCxa" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726354AbgCZGW6 (ORCPT ); Thu, 26 Mar 2020 02:22:58 -0400 Received: from mail-wm1-f65.google.com ([209.85.128.65]:51276 "EHLO mail-wm1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726210AbgCZGW5 (ORCPT ); Thu, 26 Mar 2020 02:22:57 -0400 Received: by mail-wm1-f65.google.com with SMTP id c187so5249703wme.1 for ; Wed, 25 Mar 2020 23:22:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=brainfault-org.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=mkmDzl8QbMEyVDVqrUppr7SgDLQJmLXWVe0+y40YkLQ=; b=cp6ZDCxaq81LNJbQvsBg96fKgf6ZLLSfrJC1gse9F0mRsZJ/E/CfeduBoijTSjEgI8 92mrlCu/QRyMwysaKbf3S10EvHDt3xUM1gltecPNi0NPXd1h9VYfQZXJv+14KaPehTfF XFK3y4zipTKxlxIC8qG+sIOvEhT843CIBDBrW5aDC3F7hOdzIeOrz9ZzqC452DR7QWml xaPM4bebCKBc7/yoCH1wWbDjIkZAK/JhY777wvCgQVvRpjtgWoNCP6i5HPlaC/1PiMM7 utICdp6oJidA6sGO2ZBX0TwlySPeDBunBWrHQv719z6srOljbJY9NYkH6esvzH2qhB1C dY4A== 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=mkmDzl8QbMEyVDVqrUppr7SgDLQJmLXWVe0+y40YkLQ=; b=XecHdhyXQBj92xWBGrfjUcJiFOCNj7tV2vAEgohYcmkWhBxjH/RqTF9wTQg5fNLoh4 IH9qftFE2Lb6znlj7GTaSx3w3etfk9U2yitQx43lqkJGuqXecmyBzz3Eo+UhT3XRmyuM 7pEuqHOYusaOkdYKjDzl9DgvGAdM8ten8WZNyiBdZdL1uCIEafdmhUAwNbjvPHuyeC1u XszmKiMcDWEk2QV6tu39Us25qs80Mf+cBFFikNdg7EFmqLpi5ZeM8VJ+sRUOxAWjX9Tv SLitDyXeCfBd/GfSoQOI6UxQi0256eSB6fZtri9eqfqLf/m+OqxtONwMeLWN0pjLfYoI lGmQ== X-Gm-Message-State: ANhLgQ3XyuYBuvKg2k1xuBNi+ySs6YCvPJt7L2VIDjF8rs9rCDAk/enW 67iHbbyJtge/lh5dGSKvOWATq7E33xFAu+8x/wkfJQ== X-Google-Smtp-Source: ADFU+vtinS1iUyTOVFsP36QDgeheDLi0Xo5es3e+rBfKshHjs5MZosDzi+17UBS5VghfWVwjpwhb64xgNFDR5B/lhSY= X-Received: by 2002:a1c:5452:: with SMTP id p18mr1458497wmi.102.1585203774917; Wed, 25 Mar 2020 23:22:54 -0700 (PDT) MIME-Version: 1.0 References: <20200322110028.18279-1-alex@ghiti.fr> <20200322110028.18279-4-alex@ghiti.fr> In-Reply-To: <20200322110028.18279-4-alex@ghiti.fr> From: Anup Patel Date: Thu, 26 Mar 2020 11:52:43 +0530 Message-ID: Subject: Re: [RFC PATCH 3/7] riscv: Simplify MAXPHYSMEM config To: Alexandre Ghiti Cc: Paul Walmsley , Palmer Dabbelt , Zong Li , Christoph Hellwig , linux-riscv , "linux-kernel@vger.kernel.org List" Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Mar 22, 2020 at 4:33 PM Alexandre Ghiti wrote: > > Either the user specifies maximum physical memory size of 2GB or the > user lives with the system constraint which is 128GB in 64BIT for now. > > Signed-off-by: Alexandre Ghiti > --- > arch/riscv/Kconfig | 20 ++++++-------------- > 1 file changed, 6 insertions(+), 14 deletions(-) > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > index 8e4b1cbcf2c2..a475c78e66bc 100644 > --- a/arch/riscv/Kconfig > +++ b/arch/riscv/Kconfig > @@ -104,7 +104,7 @@ config PAGE_OFFSET > default 0xC0000000 if 32BIT && MAXPHYSMEM_2GB > default 0x80000000 if 64BIT && !MMU > default 0xffffffff80000000 if 64BIT && MAXPHYSMEM_2GB > - default 0xffffffe000000000 if 64BIT && MAXPHYSMEM_128GB > + default 0xffffffe000000000 if 64BIT && !MAXPHYSMEM_2GB > > config ARCH_FLATMEM_ENABLE > def_bool y > @@ -216,19 +216,11 @@ config MODULE_SECTIONS > bool > select HAVE_MOD_ARCH_SPECIFIC > > -choice > - prompt "Maximum Physical Memory" > - default MAXPHYSMEM_2GB if 32BIT > - default MAXPHYSMEM_2GB if 64BIT && CMODEL_MEDLOW > - default MAXPHYSMEM_128GB if 64BIT && CMODEL_MEDANY > - > - config MAXPHYSMEM_2GB > - bool "2GiB" > - config MAXPHYSMEM_128GB > - depends on 64BIT && CMODEL_MEDANY > - bool "128GiB" > -endchoice > - > +config MAXPHYSMEM_2GB > + bool "Maximum Physical Memory 2GiB" > + default y if 32BIT > + default y if 64BIT && CMODEL_MEDLOW > + default n > > config SMP > bool "Symmetric Multi-Processing" > -- > 2.20.1 > Currently, we don't have systems with 256 GB or more memory but I am sure quite a few organizations are working on server class RISC-V. Let's not force RV64 physical memory limit to 128GB by removing MAXPHYSMEM_128GB. On the contrary, I suggest to have more options such as MAXPHYSMEM_256GB, MAXPHYSMEM_512GB, and MAXPHYSMEM_1TB. Regards, Anup