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=-5.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_MUTT 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 3E0D7C43381 for ; Mon, 4 Mar 2019 07:08:05 +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 D5E4021019 for ; Mon, 4 Mar 2019 07:08:04 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="L1wRvU+b"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="wnq/dC1u" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D5E4021019 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+infradead-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=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=5Cq0F/OcS+S+yTDEy7UhENqmHXgdpl/zIcQ6QL/ZVQM=; b=L1wRvU+bHUAQCY mnbZEJR/clkuLvV2APRwzih08Kk3xEpq2b1Gh1PiIBkOvHeiiF3Um8rXcQLku24kKDRRUBVRrqc8f /Xw7hDN5rUw/NwIrevRPqtUm4LWILyxkd3llYpWXPmWPUn/smISC8HUx8kWPUNEYj5GqImPWIzcbw f+JA1/eSrS20vXN4wQbrTELL3X/CjvL9bGmGt3YwK35nck/X2p/reJ2S8NYLCGeRPxmhetVRmScJz 1OYCf/pviBGDoY36E8KACjjV7tGolhn2FkJ1sMZqZbLkTz6XAg/Qc4JKUzPK+8zFxPhRHO3ZoPFvQ Cmy9BdoilunS/Y5Zf8BA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1h0hhj-0006If-GZ; Mon, 04 Mar 2019 07:08:03 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1h0hhg-0006IM-15 for linux-arm-kernel@lists.infradead.org; Mon, 04 Mar 2019 07:08:01 +0000 Received: from dragon (61-216-91-114.HINET-IP.hinet.net [61.216.91.114]) (using TLSv1.2 with cipher DHE-RSA-AES128-SHA (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 9131E20836; Mon, 4 Mar 2019 07:07:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1551683279; bh=p/j28TwQWOWVjQgNJ7cyFkh77czB4ul3jSIbWF43Dr4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=wnq/dC1uXX8bZRb71xeOW2PWtstTXjuJ6nWZLLaps2qZG/i9qtzfhHlKbpnNpcr9f 7aZKIapmXMoDpEn1UpLnDwWfAytA2b4h28t93wfQgb5P/UoXkCYCK9HOitG72Y0ZhX ewpE79Yt8pnu5jM+u+x8L8wNC3D9v8bVLTBpsCVE= Date: Mon, 4 Mar 2019 15:06:58 +0800 From: Shawn Guo To: Kohji Okuno Subject: Re: [PATCH v3] ARM: imx6q: cpuidle: fix bug that CPU might not wake up at expected time Message-ID: <20190304070656.GF26041@dragon> References: <20190222.174953.431124434951497467.okuno.kohji@jp.panasonic.com> <20190226023413.19531-1-okuno.kohji@jp.panasonic.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20190226023413.19531-1-okuno.kohji@jp.panasonic.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190303_230800_090505_7CC093F0 X-CRM114-Status: GOOD ( 12.93 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Fabio Estevam , Sascha Hauer , Pengutronix Kernel Team , linux-arm-kernel@lists.infradead.org, NXP Linux Team Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, Feb 26, 2019 at 11:34:13AM +0900, Kohji Okuno wrote: > In the current cpuidle implementation for i.MX6q, the CPU that sets > 'WAIT_UNCLOCKED' and the CPU that returns to 'WAIT_CLOCKED' are always > the same. While the CPU that sets 'WAIT_UNCLOCKED' is in IDLE state of > "WAIT", if the other CPU wakes up and enters IDLE state of "WFI" > istead of "WAIT", this CPU can not wake up at expired time. > Because, in the case of "WFI", the CPU must be waked up by the local > timer interrupt. But, while 'WAIT_UNCLOCKED' is set, the local timer > is stopped, when all CPUs execute "wfi" instruction. As a result, the > local timer interrupt is not fired. > In this situation, this CPU will wake up by IRQ different from local > timer. (e.g. broacast tiemr) s/tiemr/timer > > So, this fix changes CPU to return to 'WAIT_CLOCKED'. > > Signed-off-by: Kohji Okuno Applied the patch with following Fixes tag. Fixes: e5f9dec8ff5f ("ARM: imx6q: support WAIT mode using cpuidle") Thanks for the fixing. Shawn _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel