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=-10.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=ham 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 C0A15C433E1 for ; Mon, 17 Aug 2020 12:58:12 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (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 8B67E207DA for ; Mon, 17 Aug 2020 12:58:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="AWRZRo+W"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="q5my1Mwo" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8B67E207DA Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Type: Content-Transfer-Encoding:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:Message-ID:References:In-Reply-To:Subject:To:From: Date:MIME-Version:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=7znz0zU5X0MwPpIuRAhRWc0gsNNLw1ERxEflg22p1wQ=; b=AWRZRo+WLuh62lngNJPgsPt1h E2Lsy0i38bXc2d3YVq7Mt/lqe6dmmWBY0CuDQtey8a3ylR5mgapZvJljqry3D7YSFZU6nDBII4tYS w6pGI98+0JTDoJ31nhiWM08rxD5lJADZW7ZcRPpGI/rqD1I3saVll4ukRDiQJLqyyednHuEzf4ygb 5xuLO9n+/xRnay9R4jU/Xijy1T6irzLr0P8yuRFjRC/HvqTGat9VxzYp8Cb+S5WxddYVWRcH6GvQl ygEgQSjyWEmfjngdOdkuA1TVnzUj/y22Z6m9lzRIU4eDuYPIQ2Lt2P/oIQ3b46rAeAvhhIAKybLeH ElGQWTm1Q==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1k7eh2-0001V7-R3; Mon, 17 Aug 2020 12:56:52 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1k7eh0-0001Ua-Mq for linux-arm-kernel@lists.infradead.org; Mon, 17 Aug 2020 12:56:51 +0000 Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id ADC552072E; Mon, 17 Aug 2020 12:56:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597669009; bh=ERpMAdayk233Labrw+Lu7muZTEwuPknh19NdvGNHSMI=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=q5my1Mwo8/rP50v751943fs0FGAFtFae1A+Dz+biD7l+GcRGAiMRNkn8qGgI7zspP cEpukEBSMsw3z7ejoG8++F6AGY8JyrdeuevwPlIHFlvr6yP17ft7SPLeS6htKMEAqd XXVaERjnM8M8XvIYIw2P3xjXzpyt9obh8PR2A21U= Received: from disco-boy.misterjones.org ([51.254.78.96] helo=www.loen.fr) by disco-boy.misterjones.org with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.92) (envelope-from ) id 1k7egy-003ZLe-9G; Mon, 17 Aug 2020 13:56:48 +0100 MIME-Version: 1.0 Date: Mon, 17 Aug 2020 13:56:48 +0100 From: Marc Zyngier To: Keqian Zhu Subject: Re: [PATCH 2/2] clocksource: arm_arch_timer: Correct fault programming of CNTKCTL_EL1.EVNTI In-Reply-To: <20200817122415.6568-3-zhukeqian1@huawei.com> References: <20200817122415.6568-1-zhukeqian1@huawei.com> <20200817122415.6568-3-zhukeqian1@huawei.com> User-Agent: Roundcube Webmail/1.4.7 Message-ID: X-Sender: maz@kernel.org X-SA-Exim-Connect-IP: 51.254.78.96 X-SA-Exim-Rcpt-To: zhukeqian1@huawei.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, steven.price@arm.com, drjones@redhat.com, catalin.marinas@arm.com, will@kernel.org, james.morse@arm.com, suzuki.poulose@arm.com, wanghaibin.wang@huawei.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200817_085650_893140_67CE5375 X-CRM114-Status: GOOD ( 20.01 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Andrew Jones , kvm@vger.kernel.org, Suzuki K Poulose , Catalin Marinas , linux-kernel@vger.kernel.org, Steven Price , James Morse , wanghaibin.wang@huawei.com, Will Deacon , kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 2020-08-17 13:24, Keqian Zhu wrote: > ARM virtual counter supports event stream, it can only trigger an event > when the trigger bit (the value of CNTKCTL_EL1.EVNTI) of CNTVCT_EL0 > changes, > so the actual period of event stream is 2^(cntkctl_evnti + 1). For > example, > when the trigger bit is 0, then virtual counter trigger an event for > every > two cycles. > > Signed-off-by: Marc Zyngier I have never given you this tag, you are making it up. Please read Documentation/process/submitting-patches.rst to understand what tag you can put by yourself. At best, put "Suggested-by" tag, as this is different from what I posted anyway. Thanks, M. > Signed-off-by: Keqian Zhu > --- > drivers/clocksource/arm_arch_timer.c | 10 +++++++--- > 1 file changed, 7 insertions(+), 3 deletions(-) > > diff --git a/drivers/clocksource/arm_arch_timer.c > b/drivers/clocksource/arm_arch_timer.c > index 6e11c60..4140a37 100644 > --- a/drivers/clocksource/arm_arch_timer.c > +++ b/drivers/clocksource/arm_arch_timer.c > @@ -794,10 +794,14 @@ static void arch_timer_configure_evtstream(void) > { > int evt_stream_div, pos; > > - /* Find the closest power of two to the divisor */ > - evt_stream_div = arch_timer_rate / ARCH_TIMER_EVT_STREAM_FREQ; > + /* > + * Find the closest power of two to the divisor. As the event > + * stream can at most be generated at half the frequency of the > + * counter, use half the frequency when computing the divider. > + */ > + evt_stream_div = arch_timer_rate / ARCH_TIMER_EVT_STREAM_FREQ / 2; > pos = fls(evt_stream_div); > - if (pos > 1 && !(evt_stream_div & (1 << (pos - 2)))) > + if ((pos == 1) || (pos > 1 && !(evt_stream_div & (1 << (pos - 2))))) > pos--; > /* enable event stream */ > arch_timer_evtstrm_enable(min(pos, 15)); -- Jazz is not dead. It just smells funny... _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel