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=-13.2 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, 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 880D4C43387 for ; Mon, 7 Jan 2019 19:12:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4A97F206B7 for ; Mon, 7 Jan 2019 19:12:05 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ti.com header.i=@ti.com header.b="xiyAAcOF" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727410AbfAGTME (ORCPT ); Mon, 7 Jan 2019 14:12:04 -0500 Received: from fllv0015.ext.ti.com ([198.47.19.141]:51776 "EHLO fllv0015.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726821AbfAGTME (ORCPT ); Mon, 7 Jan 2019 14:12:04 -0500 Received: from fllv0034.itg.ti.com ([10.64.40.246]) by fllv0015.ext.ti.com (8.15.2/8.15.2) with ESMTP id x07JBwMZ010111; Mon, 7 Jan 2019 13:11:58 -0600 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1546888318; bh=63H/4aZfU8Hujhufwqdhr+dsCQQrHDmjLCPwcAgjN2Y=; h=Date:From:To:CC:Subject:References:In-Reply-To; b=xiyAAcOFy4a4PKKMO8o3zgMnev8iKeGRe6f82CoP4qeyz3ib3SJCdYov2q++mxpMA IZzBvsN1Cy+/GlkvQU2eIKs47b2R8rook5XTpySuQbFuuvF7iQ3jyc2FuQcvPP+l+Q mpy+kTm8cOtqVIgI0EqzbpRiFS83FAzme6DN4eiU= Received: from DFLE104.ent.ti.com (dfle104.ent.ti.com [10.64.6.25]) by fllv0034.itg.ti.com (8.15.2/8.15.2) with ESMTPS id x07JBwt2004478 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Mon, 7 Jan 2019 13:11:58 -0600 Received: from DFLE100.ent.ti.com (10.64.6.21) by DFLE104.ent.ti.com (10.64.6.25) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1591.10; Mon, 7 Jan 2019 13:11:57 -0600 Received: from dlep32.itg.ti.com (157.170.170.100) by DFLE100.ent.ti.com (10.64.6.21) with Microsoft SMTP Server (version=TLS1_0, cipher=TLS_RSA_WITH_AES_256_CBC_SHA) id 15.1.1591.10 via Frontend Transport; Mon, 7 Jan 2019 13:11:57 -0600 Received: from localhost (ileax41-snat.itg.ti.com [10.172.224.153]) by dlep32.itg.ti.com (8.14.3/8.13.8) with ESMTP id x07JBvTY031916; Mon, 7 Jan 2019 13:11:57 -0600 Date: Mon, 7 Jan 2019 13:11:57 -0600 From: Bin Liu To: Paul Elder CC: , , Nicolas Boichat , , , , Subject: Re: [PATCH] usb: gadget: musb: fix short isoc packets with inventra dma for pandaboard es Message-ID: <20190107191137.GA25910@uda0271908> Mail-Followup-To: Bin Liu , Paul Elder , laurent.pinchart@ideasonboard.com, kieran.bingham@ideasonboard.com, Nicolas Boichat , gregkh@linuxfoundation.org, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, balbi@kernel.org References: <20181009063220.13745-1-paul.elder@ideasonboard.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20181009063220.13745-1-paul.elder@ideasonboard.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Paul, Sorry for the delay on reviewing it. For the subject, can you please use usb: musb: gadget: fix short isoc packets with inventra dma On Tue, Oct 09, 2018 at 02:32:20AM -0400, Paul Elder wrote: > Handling short packets (length < max packet size) in the Inventra DMA > engine in the MUSB driver causes the MUSB DMA controller to hang. An > example of a problem that is caused by this problem is when streaming > video out of a UVC gadget, only the first video frame is transferred. > > For short packets (mode-0 or mode-1 DMA), MUSB_TXCSR_TXPKTRDY must be > set manually by the driver. This was previously done in musb_g_tx > (musb_gadget.c), but incorrectly (all csr flags were cleared, and only > MUSB_TXCSR_MODE and MUSB_TXCSR_TXPKTRDY). Fixing that problem allows > some requests to be transferred correctly, but multiple requests were > often put together in one USB packet, and caused problems if the packet > size was not a multiple of 4. > > Instead, MUSB_TXCSR_TXPKTRDY is set in dma_controller_irq (musbhsdma.c), > just like host mode transfers, then musb_g_tx forces the packet to be > flushed, by setting MUSB_TXCSR_FLUSHFIFO. > > This topic was originally tackled by Nicolas Boichat [0] [1] and is discussed this line is longer than 75 chars. > further at [2] as part of his GSoC project [3]. > > [0] https://groups.google.com/forum/?hl=en#!topic/beagleboard-gsoc/k8Azwfp75CU > [1] https://gitorious.org/beagleboard-usbsniffer/beagleboard-usbsniffer-kernel/commit/b0be3b6cc195ba732189b04f1d43ec843c3e54c9?p=beagleboard-usbsniffer:beagleboard-usbsniffer-kernel.git;a=patch;h=b0be3b6cc195ba732189b04f1d43ec843c3e54c9 > [2] http://beagleboard-usbsniffer.blogspot.com/2010/07/musb-isochronous-transfers-fixed.html > [3] http://elinux.org/BeagleBoard/GSoC/USBSniffer > > I have forward-ported this patch from 2.6.34 to 4.19-rc1. this line is irrelevant to the commit message, please move it down to under '---'. > > Signed-off-by: Paul Elder > --- > drivers/usb/musb/musb_gadget.c | 21 ++++++++++++++------- > drivers/usb/musb/musbhsdma.c | 21 +++++++++++---------- > 2 files changed, 25 insertions(+), 17 deletions(-) > > diff --git a/drivers/usb/musb/musb_gadget.c b/drivers/usb/musb/musb_gadget.c > index eae8b1b1b45b..d3f33f449445 100644 > --- a/drivers/usb/musb/musb_gadget.c > +++ b/drivers/usb/musb/musb_gadget.c > @@ -479,11 +479,16 @@ void musb_g_tx(struct musb *musb, u8 epnum) > && (request->actual == request->length)) > short_packet = true; > > - if ((musb_dma_inventra(musb) || musb_dma_ux500(musb)) && > - (is_dma && (!dma->desired_mode || > - (request->actual & > - (musb_ep->packet_sz - 1))))) > - short_packet = true; > + if (is_dma && (musb_dma_inventra(musb) || musb_dma_ux500(musb))) { more than 80 chars. > + if (!dma->desired_mode || I understand you forward-port Nicolas' patch, but do you have a specific readon to re-write this 'if' condition? I'd like to see minimum code change in bug fixes, > + request->actual % musb_ep->packet_sz) { but I like this version though, easier to read. > + musb_dbg(musb, "%s Flushing (FIFO) EP : KPB\n", what is 'KPB'? the message could be more meaningful? > + musb_ep->end_point.name); > + musb_writew(epio, MUSB_TXCSR, > + csr | MUSB_TXCSR_FLUSHFIFO); What if without this line? The short packet doesn't send out? setting TXSCR_TXPKTRDY in the dma driver is not sufficient? TXSCR_FLUSHFIFO is only used for aborting cases. > + return; > + } > + } > > if (short_packet) { > /* > @@ -493,8 +498,10 @@ void musb_g_tx(struct musb *musb, u8 epnum) > if (csr & MUSB_TXCSR_TXPKTRDY) > return; > > - musb_writew(epio, MUSB_TXCSR, MUSB_TXCSR_MODE > - | MUSB_TXCSR_TXPKTRDY); > + musb_dbg(musb, "sending zero pkt (zero=%d, length=%d, actual=%d, dma->desired_mode=%d)\n", > + request->zero, request->length, request->actual, more than 80 chars. > + dma->desired_mode); > + musb_writew(epio, MUSB_TXCSR, csr | MUSB_TXCSR_TXPKTRDY); more than 80 chars. > request->zero = 0; > } > > diff --git a/drivers/usb/musb/musbhsdma.c b/drivers/usb/musb/musbhsdma.c > index a688f7f87829..e514d4700a6b 100644 > --- a/drivers/usb/musb/musbhsdma.c > +++ b/drivers/usb/musb/musbhsdma.c > @@ -346,12 +346,10 @@ static irqreturn_t dma_controller_irq(int irq, void *private_data) > channel->status = MUSB_DMA_STATUS_FREE; > > /* completed */ > - if ((devctl & MUSB_DEVCTL_HM) > - && (musb_channel->transmit) > - && ((channel->desired_mode == 0) > - || (channel->actual_len & > - (musb_channel->max_packet_sz - 1))) > - ) { > + if (musb_channel->transmit && > + (!channel->desired_mode || > + (channel->actual_len % > + musb_channel->max_packet_sz))) { improper indentation. > u8 epnum = musb_channel->epnum; > int offset = musb->io.ep_offset(epnum, > MUSB_TXCSR); > @@ -363,11 +361,14 @@ static irqreturn_t dma_controller_irq(int irq, void *private_data) > */ > musb_ep_select(mbase, epnum); > txcsr = musb_readw(mbase, offset); > - txcsr &= ~(MUSB_TXCSR_DMAENAB > + if (channel->desired_mode == 1) { > + txcsr &= ~(MUSB_TXCSR_DMAENAB > | MUSB_TXCSR_AUTOSET); > - musb_writew(mbase, offset, txcsr); > - /* Send out the packet */ > - txcsr &= ~MUSB_TXCSR_DMAMODE; > + musb_writew(mbase, offset, txcsr); more than 80 chars. > + /* Send out the packet */ > + txcsr &= ~MUSB_TXCSR_DMAMODE; > + txcsr |= MUSB_TXCSR_DMAENAB; > + } > txcsr |= MUSB_TXCSR_TXPKTRDY; > musb_writew(mbase, offset, txcsr); > } Regards, -Bin.