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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4443DC433FE for ; Fri, 11 Feb 2022 07:43:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347789AbiBKHnm (ORCPT ); Fri, 11 Feb 2022 02:43:42 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:51484 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243198AbiBKHnk (ORCPT ); Fri, 11 Feb 2022 02:43:40 -0500 Received: from alexa-out.qualcomm.com (alexa-out.qualcomm.com [129.46.98.28]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E76AF250; Thu, 10 Feb 2022 23:43:39 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; i=@quicinc.com; q=dns/txt; s=qcdkim; t=1644565420; x=1676101420; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=DSnJteDARUlrsjbSpn5agFSV825dv8HSaJ68vz1hIpc=; b=H/kHE4NQ5ikn8hoUayiwE1jok+YDuiRe2eheyDvZcR4yN+/zmVjV/C1W aabWB1wGOnY7aSlbcpt7431TJ5ewYUMYO1BCayTi5N+qdzc2igKF2OV5z FRQMdN+30VsGAAwz+TF/I+JqaD7pbuoyhcxGcYE1BeSMxsrfl19w/Z1OB U=; Received: from ironmsg09-lv.qualcomm.com ([10.47.202.153]) by alexa-out.qualcomm.com with ESMTP; 10 Feb 2022 23:43:39 -0800 X-QCInternal: smtphost Received: from nalasex01a.na.qualcomm.com ([10.47.209.196]) by ironmsg09-lv.qualcomm.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Feb 2022 23:43:39 -0800 Received: from hu-pkondeti-hyd.qualcomm.com (10.80.80.8) by nalasex01a.na.qualcomm.com (10.47.209.196) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.922.19; Thu, 10 Feb 2022 23:43:35 -0800 Date: Fri, 11 Feb 2022 13:13:31 +0530 From: Pavan Kondeti To: Pavan Kondeti CC: Mathias Nyman , Jung Daehwan , Greg Kroah-Hartman , , , Subject: Re: usb: host: Reduce xhci_handshake timeout in xhci_reset Message-ID: <20220211074331.GA12625@hu-pkondeti-hyd.qualcomm.com> References: <1624361096-41282-1-git-send-email-dh10.jung@samsung.com> <20210628022548.GA69289@ubuntu> <20210628065553.GA83203@ubuntu> <496c9d86-70d7-1050-5bbb-9f841e4b464a@intel.com> <20220211064630.GA20567@hu-pkondeti-hyd.qualcomm.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20220211064630.GA20567@hu-pkondeti-hyd.qualcomm.com> User-Agent: Mutt/1.5.24 (2015-08-30) X-Originating-IP: [10.80.80.8] X-ClientProxiedBy: nasanex01a.na.qualcomm.com (10.52.223.231) To nalasex01a.na.qualcomm.com (10.47.209.196) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Sorry for the spam. I have added an incorrect email address in my previous email. On Fri, Feb 11, 2022 at 12:16:30PM +0530, Pavan Kondeti wrote: > On Mon, Jun 28, 2021 at 10:49:00AM +0300, Mathias Nyman wrote: > > On 28.6.2021 9.55, Jung Daehwan wrote: > > > On Mon, Jun 28, 2021 at 08:53:02AM +0200, Greg Kroah-Hartman wrote: > > >> On Mon, Jun 28, 2021 at 11:25:48AM +0900, Jung Daehwan wrote: > > >>> On Tue, Jun 22, 2021 at 09:56:20PM +0200, Greg Kroah-Hartman wrote: > > >>>> On Tue, Jun 22, 2021 at 08:24:56PM +0900, Daehwan Jung wrote: > > >>>>> It seems 10 secs timeout is too long in general case. A core would wait for > > >>>>> 10 secs without doing other task and it can be happended on every device. > > >>>> > > >>>> Only if the handshake does not come back sooner, right? > > >>> > > >>> Yes, right. > > >>> > > >>>> What is causing your device to timeout here? > > >>> > > >>> Host Controller doesn't respond handshake. I don't know why and I ask HW team > > >>> to debug it. > > >> > > >> Please work to fix your hardware, that feels like the root of the > > >> problem here. If you require the timeout for xhci_reset() to happen, > > >> then how do you know that the hardware really did reset properly in the > > >> reduced amount of time you just provided? > > >> > > > > > > I continue fixing this issue with hardware engineer, but currently just > > > host controller can crash whole system and that's why I want to fix it. > > > How about adding some error logs in this situation for recognizing this issue? > > > We can add error log in xhci_stop as xhci_reset can returns error like below. > > > > > > static void xhci_stop(struct usb_hcd *hcd) > > > { > > > u32 temp; > > > struct xhci_hcd *xhci = hcd_to_xhci(hcd); > > > + int ret; > > > > > > mutex_lock(&xhci->mutex); > > > > > > @@ -733,6 +734,9 @@ static void xhci_stop(struct usb_hcd *hcd) > > > xhci->cmd_ring_state = CMD_RING_STATE_STOPPED; > > > xhci_halt(xhci); > > > xhci_reset(xhci); > > > + if (ret) > > > + xhci_err(xhci, "%s: Error while reset xhci Host controller - ret = %d\n" > > > + , __func__, ret); > > > spin_unlock_irq(&xhci->lock); > > > > > > > We can check the xhci_reset() return value here and print a message, makes sense. > > > > The original reason for the 10 second timeout was because a host actually took 9 seconds: > > > > commit 22ceac191211cf6688b1bf6ecd93c8b6bf80ed9b > > > > xhci: Increase reset timeout for Renesas 720201 host. > > > > The NEC/Renesas 720201 xHCI host controller does not complete its reset > > within 250 milliseconds. In fact, it takes about 9 seconds to reset the > > host controller, and 1 second for the host to be ready for doorbell > > rings. Extend the reset and CNR polling timeout to 10 seconds each. > > > Agreed. > > We also run into the similar issue (very very rarely reproduced) on > our platforms like SM8450. The issue happens when host mode is de-activated > (type-c cable disconnected). Since xhci_reset() is called with interrupts > disabled, a timeout of 10 seconds is fatal to the system. > > Thanks, > Pavan