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=-2.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 3A321C3A59E for ; Wed, 21 Aug 2019 07:19:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F026F2332A for ; Wed, 21 Aug 2019 07:19:02 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="XlfBb6l6" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727825AbfHUHTC (ORCPT ); Wed, 21 Aug 2019 03:19:02 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:56008 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727504AbfHUHTB (ORCPT ); Wed, 21 Aug 2019 03:19:01 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=Wg093CFP8rWbJ5T0bFIIG6yDkp8tCiGp/vtNNNDB0ho=; b=XlfBb6l6Fi1ORNmTRRnKPiEd3 K54YEt5Bi3CfgH02N8OJQvSGdsl5vjs0iwV/ROeu5NlnelDDjhOkziKIS6WSwlQQhS6UqubSEUfwI oisS1oibc0LvP3G5bwVOl1voNx0JB3Hn6UNq63jZflgO4n5WgbTuQzj5d48+07Mi8KAFECv1mtRlF yceioRfR9FjCoPkAe9qsB4qMyzZrCIWc4tTC+M6ZCYPI7yRdy8iSGPHs4Ds1vsfst7IMuQiWdt/Rq CkIwKgFHRCenCvDKg2STzvkOdgCL+f4ao095g9FvJA+9R3KzIBaEtCjaQ8usOh+L5xAg1yD1YODYv jQOC+l7Tw==; Received: from hch by bombadil.infradead.org with local (Exim 4.92 #3 (Red Hat Linux)) id 1i0KtT-0008Oa-8j; Wed, 21 Aug 2019 07:18:55 +0000 Date: Wed, 21 Aug 2019 00:18:55 -0700 From: "hch@infradead.org" To: Anup Patel Cc: "hch@infradead.org" , Alan Kao , Atish Patra , "aou@eecs.berkeley.edu" , "palmer@sifive.com" , "linux-kernel@vger.kernel.org" , "schwab@linux-m68k.org" , "paul.walmsley@sifive.com" , "linux-riscv@lists.infradead.org" , "allison@lohutok.net" Subject: Re: [v2 PATCH] RISC-V: Optimize tlb flush path. Message-ID: <20190821071855.GA32145@infradead.org> References: <20190820004735.18518-1-atish.patra@wdc.com> <20190820092207.GA26271@infradead.org> <76467815b464709f4c899444c957d921ebac87db.camel@wdc.com> <20190821012921.GA30187@andestech.com> <20190821014052.GA25550@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.11.4 (2019-03-13) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Aug 21, 2019 at 09:22:48AM +0530, Anup Patel wrote: > I agree that IPI mechanism should be standardized for RISC-V but I > don't support the idea of mandating CLINT as part of the UNIX > platform spec. For example, the AndesTech SOC does not use CLINT > instead they have PLMT for per-HART timer and PLICSW for per-HART > IPIs. The point is not really mandating a CLINT as know right now. The point is to mandate one way to issue IPIs from S-mode to S-mode, one way to read the time counter and one way to write the timer threshold.