Received: by 2002:a25:8b12:0:0:0:0:0 with SMTP id i18csp3892919ybl; Mon, 12 Aug 2019 08:05:13 -0700 (PDT) X-Google-Smtp-Source: APXvYqysA+smHGcz7wF6VuEXsa8arRHtGCOgjX13/J1ZGxTdXVM70CcHXNKZeuZG4GSulmk1UbdN X-Received: by 2002:a17:90a:1ae1:: with SMTP id p88mr23011873pjp.26.1565622313560; Mon, 12 Aug 2019 08:05:13 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1565622313; cv=none; d=google.com; s=arc-20160816; b=1AMNU53raLkgLWD4dTc7YczcPVHJcXRrXRAfyCekogTMGj0+pPxDxl+tDWUJyua56V v/09208AfopvvKFwU5hiR43vNuu2sYjNPoEOIQvAoNOkWoiCVFjoD61SiWykTSZt+smR uCEs1iTjfxIyaMjGlZq6wTpU09rA9SsTZ8ZBg3R0YuV8yu5SCmYgWBQ6b+9dRaEfEsiA iJkBVEwIEek0LNF99xFmXeMDQ4Jw5j73wxKYM2wf/ns3PKXx/oTs9smf45DWk3k1oFqt ZlR+Xe2EkLoINkICBJnOy9tw4Am1WtF/xdxC4ikz+yitr09ygUGZVJk+1F/ALPqyU5Xa drcQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:user-agent:in-reply-to :content-disposition:mime-version:references:message-id:subject:cc :to:from:date:dkim-signature; bh=usnoDAbB2l1gvsnQq3fkxukL1V/wPhuDb8sH4VZSJCs=; b=sEps+1+P2v6eh/wQ5ysdJXQx5ldF+GAQkW0zdUO67oKKW5yPVzKI0+Raz5XsfknC+j 7CuzrBRbHqrF2mFqVW1DURJ5AXLJ5fGOE1ei4J4/LfmW0rNRyMJDvBWNhT+DHXpRgRAz VJveVEsj9si6mkqCUb1pLr0LWf3e65Z1a6xvQr9qA3eGYWGvDW7OgGIAG4JZF9lyMVCC Bun6HDrkkdyqoBAIQSmmOwGdFqgeejS3zamD28cTzM5WXBpNQnhUFP57Wm9qXDuiYH46 q1d/JBsoL8JGTaiYUj1ZShxzbTcVOmCKrWjncli/Q5OhlrJaU7qDj6pFK+b9Dx0Xl8De D/2w== ARC-Authentication-Results: i=1; mx.google.com; dkim=fail header.i=@infradead.org header.s=bombadil.20170209 header.b=GySprv52; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id x22si66108958pfo.255.2019.08.12.08.04.57; Mon, 12 Aug 2019 08:05:13 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=fail header.i=@infradead.org header.s=bombadil.20170209 header.b=GySprv52; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727277AbfHLPDu (ORCPT + 99 others); Mon, 12 Aug 2019 11:03:50 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:38150 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726325AbfHLPDu (ORCPT ); Mon, 12 Aug 2019 11:03:50 -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=usnoDAbB2l1gvsnQq3fkxukL1V/wPhuDb8sH4VZSJCs=; b=GySprv52XAvesIHBNMZG+h0Yv DFo8Rx3ZbE29nsAOZ4p9+M33MeqAp1KEKH3E1rsKRFTZwVIMjvNP58xthWpLKFyo7e/XOOKoB3+S5 8JHAqedNqYFiuCRnsUVMzr34ZGKvxrdJ0ycD5puduWfG/6BaaXJbf34mb7oCc4Gw78FaXr5kTdSVD BgIN7wIFpYOqsaOxo2rFT9Gc8LIDsKcgiGU1v2qnJvVjsKFlKlK0sWJRmL29E53dwcRsbiA+7iCjF /STIndZa1xgv7bfzPFwigIOW7qwIKKbIKdNmsv4S3hesMY4km8RkpKUQYhxIv8xSHjKMb/RhVNYvl I/oXOkGwA==; Received: from hch by bombadil.infradead.org with local (Exim 4.92 #3 (Red Hat Linux)) id 1hxBrQ-0006NF-Tz; Mon, 12 Aug 2019 15:03:48 +0000 Date: Mon, 12 Aug 2019 08:03:48 -0700 From: Christoph Hellwig To: Charles Papon Cc: Bin Meng , Atish Patra , linux-riscv , linux-kernel , Paul Walmsley Subject: Re: [PATCH] riscv: kbuild: drop CONFIG_RISCV_ISA_C Message-ID: <20190812150348.GH26897@infradead.org> References: 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 Thu, Aug 08, 2019 at 02:18:53PM +0200, Charles Papon wrote: > Please do not drop it. > > Compressed instruction extension has some specific overhead in small > RISC-V FPGA softcore, especialy in the ones which can't implement the > register file read in a asynchronous manner because of the FPGA > technology. > What are reasons to enforce RVC ? Because it it the unix platform baseline as stated in the patch.