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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 78C60C433F5 for ; Fri, 11 Feb 2022 01:11:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346696AbiBKBLm (ORCPT ); Thu, 10 Feb 2022 20:11:42 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:50720 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241756AbiBKBLk (ORCPT ); Thu, 10 Feb 2022 20:11:40 -0500 Received: from gloria.sntech.de (gloria.sntech.de [185.11.138.130]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 446A4B4B; Thu, 10 Feb 2022 17:11:37 -0800 (PST) Received: from ip5b412258.dynamic.kabel-deutschland.de ([91.65.34.88] helo=diego.localnet) by gloria.sntech.de with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1nIKT8-0004UP-7v; Fri, 11 Feb 2022 02:11:26 +0100 From: Heiko =?ISO-8859-1?Q?St=FCbner?= To: Atish Patra Cc: Palmer Dabbelt , Paul Walmsley , Albert Ou , linux-riscv , devicetree , "linux-kernel@vger.kernel.org List" , Rob Herring , Wei Fu , liush , Guo Ren , Anup Patel , Drew Fustini , Christoph Hellwig , Arnd Bergmann , Chen-Yu Tsai , Maxime Ripard , Greg Favor , Andrea Mondelli , Jonathan Behrens , Xinhaoqu , Bill Huffman , Nick Kossifidis , Allen Baum , Josh Scheid , Richard Trauben , Samuel Holland , Christoph Muellner , Philipp Tomsich Subject: Re: [PATCH v6 08/14] riscv: move boot alternatives to a slightly earlier position Date: Fri, 11 Feb 2022 02:11:24 +0100 Message-ID: <2532021.2vfPgEiFAl@diego> In-Reply-To: References: <20220209123800.269774-1-heiko@sntech.de> <20220209123800.269774-9-heiko@sntech.de> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Atish, Am Donnerstag, 10. Februar 2022, 23:42:35 CET schrieb Atish Patra: > On Wed, Feb 9, 2022 at 4:39 AM Heiko Stuebner wrote: > > > > Move the application of boot alternatives to soc_early_init(). > > This allows to catch more generic cases of code needing patches > > than doing it in smp_prepare_boot_cpu() and also makes it actually > > work if CONFIG_SMP is disabled for whatever reason. > > > > The position is chosen mainly as it is before the actual soc early > > init runs but also already allows accessing the devicetree > > via fdt_* functions. > > > > Signed-off-by: Heiko Stuebner > > --- > > arch/riscv/kernel/head.S | 2 ++ > > arch/riscv/kernel/smpboot.c | 2 -- > > 2 files changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S > > index 2363b43312fc..0e1bb97f9749 100644 > > --- a/arch/riscv/kernel/head.S > > +++ b/arch/riscv/kernel/head.S > > @@ -10,6 +10,7 @@ > > #include > > #include > > #include > > +#include > > #include > > #include > > #include > > @@ -341,6 +342,7 @@ clear_bss_done: > > call kasan_early_init > > #endif > > /* Start the kernel */ > > + call apply_boot_alternatives > > Do you really need this early ? > if non-smp configuration is the only option, Can you do it in > setup_arch() after riscv_fill_hwcap() is called ? The issue I see is, we we have the soc_early_init [0] running directly after this and the one user I see [1] already wants to ioremap io-memory at this stage. So judging by the fact that more early-inits will get added in the future I do guess we should've set up the io-memory page-type by this point? Heiko [0] https://elixir.bootlin.com/linux/latest/source/arch/riscv/kernel/soc.c#L14 [1] https://elixir.bootlin.com/linux/latest/source/drivers/soc/canaan/k210-sysctl.c#L66 > By doing that, we can unify the cpu feature probing and you don't need > a separate DT parsing just for svpbmt. > > > call soc_early_init > > tail start_kernel > > > > diff --git a/arch/riscv/kernel/smpboot.c b/arch/riscv/kernel/smpboot.c > > index a6d13dca1403..f1e4948a4b52 100644 > > --- a/arch/riscv/kernel/smpboot.c > > +++ b/arch/riscv/kernel/smpboot.c > > @@ -32,7 +32,6 @@ > > #include > > #include > > #include > > -#include > > > > #include "head.h" > > > > @@ -41,7 +40,6 @@ static DECLARE_COMPLETION(cpu_running); > > void __init smp_prepare_boot_cpu(void) > > { > > init_cpu_topology(); > > - apply_boot_alternatives(); > > } > > > > void __init smp_prepare_cpus(unsigned int max_cpus) > > -- > > 2.30.2 > > > > > > _______________________________________________ > > linux-riscv mailing list > > linux-riscv@lists.infradead.org > > http://lists.infradead.org/mailman/listinfo/linux-riscv > > > >