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=-2.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, 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 96CF3C4338F for ; Tue, 27 Jul 2021 11:53:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6EFDB61A40 for ; Tue, 27 Jul 2021 11:53:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231845AbhG0Lxa (ORCPT ); Tue, 27 Jul 2021 07:53:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40366 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231802AbhG0Lxa (ORCPT ); Tue, 27 Jul 2021 07:53:30 -0400 Received: from mail-il1-x131.google.com (mail-il1-x131.google.com [IPv6:2607:f8b0:4864:20::131]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 683C4C061757 for ; Tue, 27 Jul 2021 04:53:29 -0700 (PDT) Received: by mail-il1-x131.google.com with SMTP id z3so11768599ile.12 for ; Tue, 27 Jul 2021 04:53:29 -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=ZFQVbsUF6EIimG2/4GNB3iVOoIHc4+Ng0KYWa/FzcS0=; b=dwUWGtiOyzDOkdzjfWTYlYt94g1W0F0ldaNoJzgPYe3XhYJXJjYE4nSCnRXF0SP3UZ xxrwhX0+/aV12saD8M3cWxPQfsShfcGxa9tIvpyCHHtmU3vHKdSX9iI/xSVMVqYQ36dy 3MF9d/IHyAmUsrY8tz6BIMeWJIPozWSSiE+Y7VLUSqA8faeqMAQzLXhI3rTfHZ0Nspik iJAK59WVQN2p55c9yRdnii1r9hGVqHf6bN/pKyMGABXKUXVtVDoohFJF+9ZmwY0X+YGn jszPuvQ31rE8Yhw2bitkigTnB+kqlHN3KYXOyIrbBtKBsv3WDMkMIETPRngAx/98YOnV e+lA== 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=ZFQVbsUF6EIimG2/4GNB3iVOoIHc4+Ng0KYWa/FzcS0=; b=eBSmFFIsOpc1txKUgOxeqkIQK23WqPOgzSrNwPWsgZgjlI1f4o+BAUNv+tnTkSnhEy YQu9gf0aiGdYTdxnLwAJgOhMORDOdBO6jHPOyZD7RsWh+aqXI4TDIxoHcIAIvO954J37 AuXcooAGg3T785HlrjaTh202iUcX1uNmV6nbvR/03A7x0gtUk8dIYgQEDTHVpRkN3aPK Hwi9t02lRON4DHR6vQKo/r8F9dIoP6sZ+We/XiLyXHAOfHhbkKM31Av0Qk+RkXbsVTQC DX3dUAjLy1bqBBHyiwb7aIXpRmHCJgzpa1NmQCpygDHkXeIVOqROoUdRWuHFIyWod22o Wu/Q== X-Gm-Message-State: AOAM530LL2KFCNFFvH8PzN3h+DOuXFUzwIol/2G17SvnPTHfSSqbwBAD PVWY+da2HdSOS2M1M7vbVPrw3L3P/cwzvm97rnOag7YC3aA= X-Google-Smtp-Source: ABdhPJxJIRI3aw5JcZptWoCuy1CX+LaEgN16X1OO5wnbec1ldO7h2aUMDDoguTeUeu3jVknCrcUtFUg6SzsFg8jYeXw= X-Received: by 2002:a05:6e02:1c2d:: with SMTP id m13mr16156623ilh.137.1627386808922; Tue, 27 Jul 2021 04:53:28 -0700 (PDT) MIME-Version: 1.0 References: <20210706041820.1536502-1-chenhuacai@loongson.cn> <20210706041820.1536502-6-chenhuacai@loongson.cn> In-Reply-To: From: Huacai Chen Date: Tue, 27 Jul 2021 19:53:18 +0800 Message-ID: Subject: Re: [PATCH 05/19] LoongArch: Add boot and setup routines To: Arnd Bergmann Cc: Huacai Chen , Andy Lutomirski , Thomas Gleixner , Peter Zijlstra , Andrew Morton , David Airlie , Linus Torvalds , linux-arch , Xuefeng Li , Jiaxun Yang Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-arch@vger.kernel.org Hi, Arnd, On Tue, Jul 6, 2021 at 6:16 PM Arnd Bergmann wrote: > > On Tue, Jul 6, 2021 at 6:18 AM Huacai Chen wrote: > > > + > > +#ifdef CONFIG_64BIT > > + /* Guess if the sign extension was forgotten by bootloader */ > > + if (start < CAC_BASE) > > + start = (int)start; > > +#endif > > + initrd_start = start; > > + initrd_end += start; > > + return 0; > > +} > > +early_param("rd_start", rd_start_early); > > + > > +static int __init rd_size_early(char *p) > > +{ > > + initrd_end += memparse(p, &p); > > + return 0; > > +} > > +early_param("rd_size", rd_size_early); > > The early parameters should not be used for this, I'm fairly sure the UEFI > boot protocol already has ways to communicate all necessary information. We use grub to boot the Linux kernel. We found X86 uses private data structures (seems not UEFI-specific) to pass initrd information from grub to kernel. Some archs use fdt, and other archs use cmdline with "initrd=start,size" (init/do_mounts_initrd.c). So, I think use cmdline is not unacceptable, but we do can remove the the rd_start/rd_size parsing code here. > > > + > > +#ifdef CONFIG_ACPI > > + init_initrd(); > > +#endif > > Why is the initrd support tied to ACPI? Can you actually boot without ACPI? > > > +#if defined(CONFIG_VT) > > +#if defined(CONFIG_VGA_CONSOLE) > > + conswitchp = &vga_con; > > +#elif defined(CONFIG_DUMMY_CONSOLE) > > + conswitchp = &dummy_con; > > +#endif > > +#endif > > The VGA console seems rather outdated. If you have UEFI, why not use > the provided framebuffer for the console? OK, we will remove this. > > > +u64 cpu_clock_freq; > > +EXPORT_SYMBOL(cpu_clock_freq); > > +u64 const_clock_freq; > > +EXPORT_SYMBOL(const_clock_freq); > > You should generally not rely on the CPU clock frequency being fixed > like this, as this breaks down as soon as you add a drivers/cpufreq/ driver. > > What code uses these? cpu_clock_freq is a const which records the "standard frequency", it is just used to display the frequency now. In future when cpufreq added, cpu_clock_freq will be used to calculate the target frequency. Huacai > > > +void __init time_init(void) > > +{ > > + if (!cpu_has_cpucfg) > > + const_clock_freq = cpu_clock_freq; > > + else > > + const_clock_freq = calc_const_freq(); > > + > > + init_timeval = drdtime() - csr_readq(LOONGARCH_CSR_CNTC); > > + > > + constant_clockevent_init(); > > + constant_clocksource_init(); > > +} > > Clocksource and clockevents drivers should be located in drivers/clocksource > and reviewed by its maintainers. > > Arnd