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=-2.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,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 3D544C3A59F for ; Mon, 26 Aug 2019 11:30:45 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 11D75217F5 for ; Mon, 26 Aug 2019 11:30:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="n8XrNElC" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 11D75217F5 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-riscv-bounces+infradead-linux-riscv=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=AISu0ZbmtUk7qv/uEHIOZCYY4OfF31dz+lnSsc4LX9o=; b=n8XrNElCwGIC7k tuGPTNMfOOSyCq3+DcxvMkuP+zGErw2gKbLcfzd1bOw259DnJmJJ4BDgabMstgczR7SzEq447P9PK AqVX0B4+QTkB/0XOIXWwYRs0dZ6ChU3mNGBwFfGKIt0BPD2heOHogF0xM29M4s9JrkF3TqH0UMtfR 53KDpSt+Nkszd6ha+KRup4IllJA7M9HnmA7aBsNrCMrpBXzwTRKDXCxPJ4fJg0rNeVPXyhkbs/HGU elGjbspAdBQzHFT3XBbugZbZEDMoHqKG40ypAtkE1EqrjS4pX4V90fGCnfO1e3Iz2z+d3jvDEpSu/ 1Pu6rcBh6rOO1wjnbXvw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92 #3 (Red Hat Linux)) id 1i2DCr-0008IT-NL; Mon, 26 Aug 2019 11:30:41 +0000 Received: from verein.lst.de ([213.95.11.211]) by bombadil.infradead.org with esmtps (Exim 4.92 #3 (Red Hat Linux)) id 1i2DCp-00087h-T0 for linux-riscv@lists.infradead.org; Mon, 26 Aug 2019 11:30:41 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id 293A568AFE; Mon, 26 Aug 2019 13:30:35 +0200 (CEST) Date: Mon, 26 Aug 2019 13:30:34 +0200 From: "hch@lst.de" To: Atish Patra Subject: Re: [PATCH 5/6] riscv: don't use the rdtime(h) pseudo-instructions Message-ID: <20190826113034.GC15002@lst.de> References: <20190821145837.3686-1-hch@lst.de> <20190821145837.3686-6-hch@lst.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190826_043040_087616_3C060023 X-CRM114-Status: UNSURE ( 7.90 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: "linux-riscv@lists.infradead.org" , "palmer@sifive.com" , "hch@lst.de" , "paul.walmsley@sifive.com" Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+infradead-linux-riscv=archiver.kernel.org@lists.infradead.org On Sat, Aug 24, 2019 at 12:37:02AM +0000, Atish Patra wrote: > > -static inline cycles_t get_cycles_inline(void) > > +static inline cycles_t get_cycles(void) > > { > > - cycles_t n; > > - > > - __asm__ __volatile__ ( > > - "rdtime %0" > > - : "=r" (n)); > > - return n; > > + return csr_read(CSR_TIME); > > Does this work correctly in QEMU ? I was looking at the qemu code and > it looks like it returns cpu_get_host_ticks which seems wrong to me. It better should. rdtime is just a pseudo-instruction that the assembler translates to a CSR read. (in other words something totally pointless, no idea why it even is in the spec). _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv