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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 48101C433EF for ; Sat, 4 Dec 2021 00:40:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:From:References:Cc:To: Subject:MIME-Version:Date:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=SrN0tS7q83fSMWhBQBmxkz/s9RiqxZymk18ck28XqiE=; b=dchNKkx2B/r2hu /3nKDxLWKCjxSbAUEn+U8scnK9oM5tgje96KZMnlBWvTS6e3WkH5mXDSSYUKzh0eb9pldY0PPrcbo rRQMtwS370KgOw/CQ7dhhDSlrM8Ch47l6aysuzbdnQcuKzCHJnXEh+cuHEU8a6TOqlt3j/i7LIeJi OnU5OioxRKjkpJCE/Tk8Wv9aRwUvz/Pswlx9rJ6w1BJDV4sZ1kuQi/zKF59TdVgcuCOXp0iOXUWwK jKhHnYhWLgjFELFLF5uaaTSc0+WHw0qOUPpSOW3Qsb48mprFkU5tkNw3gsxJWrSMQYOtrgdJwYiBS d4hqaC4WjDCZ18Ba99+w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mtJ6V-00HL8q-T0; Sat, 04 Dec 2021 00:40:39 +0000 Received: from casper.infradead.org ([2001:8b0:10b:1236::1]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1mtJ6V-00HL8S-7x; Sat, 04 Dec 2021 00:40:39 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Transfer-Encoding:Content-Type: In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date:Message-ID:Sender :Reply-To:Content-ID:Content-Description; bh=RhO2eM2iBD51XAcs3FHaTn4vdZjIjPBsjygX6aDTNlY=; b=eSHMLB1xRxjDVw9DKqlPBAR9yp Yqrx75FNRoT77RKI0dF0PD6De0YW42GbJPUreFYgi2To8XprXRC6VqU9prtBhiwbiue1Iq5HBWr3t 3F8XNkmkECLouyBz8C3AnNxX2RC8v7QBycpZ0UFBsUVcGQBX5+YzFQ+I5xtAsdQlEPtjxB53RU4dU oqe2CCJyKi7VD/1ofD6evkbAvF4xqc/ebajcsWIBImVoKPtSPK5dAb6mI2L3MyjWN0QeZulNIE/zs SV0YEODhajuqd16opZXTesJp2A3+eC4goG2qt1FKMtwBOrm66MR8/8ctxm8K6qdvc2lSXJjOhFRP/ F8O11i8Q==; Received: from [2601:1c0:6280:3f0::aa0b] by casper.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1mtJ6O-00Awrp-Kc; Sat, 04 Dec 2021 00:40:33 +0000 Message-ID: Date: Fri, 3 Dec 2021 16:40:26 -0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.3.2 Subject: Re: [RFC 5/6] RISC-V: Move spinwait booting method to its own config Content-Language: en-US To: Atish Patra , linux-kernel@vger.kernel.org Cc: Atish Patra , Alexandre Ghiti , Anup Patel , Greentime Hu , Guo Ren , Heinrich Schuchardt , Ingo Molnar , Jisheng Zhang , kvm-riscv@lists.infradead.org, kvm@vger.kernel.org, linux-riscv@lists.infradead.org, Marc Zyngier , Nanyong Sun , Nick Kossifidis , Palmer Dabbelt , Paul Walmsley , Pekka Enberg , Vincent Chen , Vitaly Wool References: <20211204002038.113653-1-atishp@atishpatra.org> <20211204002038.113653-6-atishp@atishpatra.org> From: Randy Dunlap In-Reply-To: <20211204002038.113653-6-atishp@atishpatra.org> X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org Hi-- On 12/3/21 16:20, Atish Patra wrote: > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > index 821252b65f89..4afb42d5707d 100644 > --- a/arch/riscv/Kconfig > +++ b/arch/riscv/Kconfig > @@ -403,6 +403,20 @@ config RISCV_SBI_V01 > This config allows kernel to use SBI v0.1 APIs. This will be > deprecated in future once legacy M-mode software are no longer in use. > > +config RISCV_BOOT_SPINWAIT > + bool "Spinwait booting method" > + depends on SMP > + default y > + help > + This enables support for booting Linux via spinwait method. In the > + spinwait method, all cores randomly jump to Linux. One of the core cores > + gets chosen via lottery and all other keeps spinning on a percpu others keep > + variable. This method can not support cpu hotplug and sparse hartid cannot support CPU hotplug and sparse hartid > + scheme. It should be only enabled for M-mode Linux or platforms relying > + on older firmware without SBI HSM extension. All other platform should platforms > + rely on ordered booing via SBI HSM extension which gets chosen booting > + dynamically at runtime if the firmware supports it. dynamically at runtime if the firmware supports it. (Last line should be indented with tab + 2 spaces, not 10 spaces.) -- ~Randy _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv