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 E3362C4167B for ; Tue, 5 Dec 2023 08:37:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344835AbjLEIhM (ORCPT ); Tue, 5 Dec 2023 03:37:12 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52874 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229712AbjLEIhH (ORCPT ); Tue, 5 Dec 2023 03:37:07 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3A59EFA for ; Tue, 5 Dec 2023 00:37:13 -0800 (PST) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 99884C433C7; Tue, 5 Dec 2023 08:37:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1701765432; bh=QaChC19t84tPQ3fhVSi46FxHN4jYeXoCcq8WNBAg/w0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=hKYRHMfb4IUzwQjLfdVCGGS+Ub/LwL1X5Dsl2HE+MPu9zUDyU5PW2pIGAuj9h09iu l3eMzoX0vg8AM/J//Yh/TQ32PbbSsUyLg317MQgKOMIpsffKyUCYoUI+t5AymiXu9M 9XVNYP7IH0dVjd8Me6etnFB02TVFw1J/T2OnMe7k/l2xHokBi2otAi/zsfZvYOLAVj B00ovEuBy8I/voMgE+j3CfcU9pkHG8r52DoiimTcj/3r+uXxa8HN61iRcK2zEileQp P8sA4OqJOlVrrQzUP8QCQMukW08r6W0LMENkQ/ThbbicdZn4QtH7MOaI9ayDtpdWFW fOHTpbeV/1VGA== Date: Tue, 5 Dec 2023 16:37:06 +0800 From: Shawn Guo To: Nathan Rossi Cc: devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Nathan Rossi , Fabio Estevam , Li Jun , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Sascha Hauer , Pengutronix Kernel Team , NXP Linux Team Subject: Re: [PATCH v2] arm64: dts: imx8mp: imx8mq: Add parkmode-disable-ss-quirk on DWC3 Message-ID: <20231205083706.GC236001@dragon> References: <20231106021436.1917894-1-nathan@nathanrossi.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20231106021436.1917894-1-nathan@nathanrossi.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Nov 06, 2023 at 02:14:36AM +0000, Nathan Rossi wrote: > From: Nathan Rossi > > The i.MX8MP and i.MX8MQ devices both use the same DWC3 controller and > are both affected by a known issue with the controller due to specific > behaviour when park mode is enabled in SuperSpeed host mode operation. > > Under heavy USB traffic from multiple endpoints the controller will > sometimes incorrectly process transactions such that some transactions > are lost, or the controller may hang when processing transactions. When > the controller hangs it does not recover. > > This issue is documented partially within the linux-imx vendor kernel > which references a Synopsys STAR number 9001415732 in commits [1] and > additional details in [2]. Those commits provide some additional > controller internal implementation specifics around the incorrect > behaviour of the SuperSpeed host controller operation when park mode is > enabled. > > The summary of this issue is that the host controller can incorrectly > enter/exit park mode such that part of the controller is in a state > which behaves as if in park mode even though it is not. In this state > the controller incorrectly calculates the number of TRBs available which > results in incorrect access of the internal caches causing the overwrite > of pending requests in the cache which should have been processed but > are ignored. This can cause the controller to drop the requests or hang > waiting for the pending state of the dropped requests. > > The workaround for this issue is to disable park mode for SuperSpeed > operation of the controller through the GUCTL1[17] bit. This is already > available as a quirk for the DWC3 controller and can be enabled via the > 'snps,parkmode-disable-ss-quirk' device tree property. > > It is possible to replicate this failure on an i.MX8MP EVK with a USB > Hub connecting 4 SuperSpeed USB flash drives. Performing continuous > small read operations (dd if=/dev/sd... of=/dev/null bs=16) on the block > devices will result in device errors initially and will eventually > result in the controller hanging. > > [13240.896936] xhci-hcd xhci-hcd.0.auto: WARN Event TRB for slot 4 ep 2 with no TDs queued? > [13240.990708] usb 2-1.3: reset SuperSpeed USB device number 5 using xhci-hcd > [13241.015582] sd 2:0:0:0: [sdc] tag#0 UNKNOWN(0x2003) Result: hostbyte=0x07 driverbyte=DRIVER_OK cmd_age=0s > [13241.025198] sd 2:0:0:0: [sdc] tag#0 CDB: opcode=0x28 28 00 00 00 03 e0 00 01 00 00 > [13241.032949] I/O error, dev sdc, sector 992 op 0x0:(READ) flags 0x80700 phys_seg 25 prio class 2 > [13272.150710] usb 2-1.2: reset SuperSpeed USB device number 4 using xhci-hcd > [13272.175469] sd 1:0:0:0: [sdb] tag#0 UNKNOWN(0x2003) Result: hostbyte=0x03 driverbyte=DRIVER_OK cmd_age=31s > [13272.185365] sd 1:0:0:0: [sdb] tag#0 CDB: opcode=0x28 28 00 00 00 03 e0 00 01 00 00 > [13272.193385] I/O error, dev sdb, sector 992 op 0x0:(READ) flags 0x80700 phys_seg 18 prio class 2 > [13434.846556] xhci-hcd xhci-hcd.0.auto: xHCI host not responding to stop endpoint command > [13434.854592] xhci-hcd xhci-hcd.0.auto: xHCI host controller not responding, assume dead > [13434.862553] xhci-hcd xhci-hcd.0.auto: HC died; cleaning up > > [1] https://github.com/nxp-imx/linux-imx/commit/97a5349d936b08cf301730b59e4e8855283f815c > [2] https://github.com/nxp-imx/linux-imx/commit/b4b5cbc5a12d7c3b920d1d7cba0ada3379e4e42b > > Fixes: fb8587a2c165 ("arm64: dtsi: imx8mp: add usb nodes") > Fixes: ad37549cb5dc ("arm64: dts: imx8mq: add USB nodes") > Signed-off-by: Nathan Rossi > Reviewed-by: Fabio Estevam Applied, thanks!