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=-11.5 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable 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 5DC79C433E7 for ; Tue, 1 Sep 2020 17:13:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4926A2087D for ; Tue, 1 Sep 2020 17:13:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732530AbgIARNO (ORCPT ); Tue, 1 Sep 2020 13:13:14 -0400 Received: from elvis.franken.de ([193.175.24.41]:46009 "EHLO elvis.franken.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729705AbgIARNL (ORCPT ); Tue, 1 Sep 2020 13:13:11 -0400 Received: from uucp (helo=alpha) by elvis.franken.de with local-bsmtp (Exim 3.36 #1) id 1kD9qC-0004aY-00; Tue, 01 Sep 2020 19:13:04 +0200 Received: by alpha.franken.de (Postfix, from userid 1000) id A3E0EC0E68; Tue, 1 Sep 2020 19:12:41 +0200 (CEST) Date: Tue, 1 Sep 2020 19:12:41 +0200 From: Thomas Bogendoerfer To: Christoph Hellwig Cc: alsa-devel@alsa-project.org, linux-ia64@vger.kernel.org, linux-doc@vger.kernel.org, nouveau@lists.freedesktop.org, linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org, "James E.J. Bottomley" , linux-mm@kvack.org, Marek Szyprowski , linux-samsung-soc@vger.kernel.org, Joonyoung Shim , linux-scsi@vger.kernel.org, Kyungmin Park , Ben Skeggs , Matt Porter , linux-media@vger.kernel.org, Tom Lendacky , Pawel Osciak , Mauro Carvalho Chehab , linux-arm-kernel@lists.infradead.org, linux-parisc@vger.kernel.org, netdev@vger.kernel.org, Seung-Woo Kim , linux-mips@vger.kernel.org, iommu@lists.linux-foundation.org Subject: Re: [PATCH 22/28] sgiseeq: convert from dma_cache_sync to dma_sync_single_for_device Message-ID: <20200901171241.GA20685@alpha.franken.de> References: <20200819065555.1802761-1-hch@lst.de> <20200819065555.1802761-23-hch@lst.de> <20200901152209.GA14288@alpha.franken.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200901152209.GA14288@alpha.franken.de> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-parisc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-parisc@vger.kernel.org On Tue, Sep 01, 2020 at 05:22:09PM +0200, Thomas Bogendoerfer wrote: > On Wed, Aug 19, 2020 at 08:55:49AM +0200, Christoph Hellwig wrote: > > Use the proper modern API to transfer cache ownership for incoherent DMA. > > > > Signed-off-by: Christoph Hellwig > > --- > > drivers/net/ethernet/seeq/sgiseeq.c | 12 ++++++++---- > > 1 file changed, 8 insertions(+), 4 deletions(-) > > > > diff --git a/drivers/net/ethernet/seeq/sgiseeq.c b/drivers/net/ethernet/seeq/sgiseeq.c > > index 39599bbb5d45b6..f91dae16d69a19 100644 > > --- a/drivers/net/ethernet/seeq/sgiseeq.c > > +++ b/drivers/net/ethernet/seeq/sgiseeq.c > > @@ -112,14 +112,18 @@ struct sgiseeq_private { > > > > static inline void dma_sync_desc_cpu(struct net_device *dev, void *addr) > > { > > - dma_cache_sync(dev->dev.parent, addr, sizeof(struct sgiseeq_rx_desc), > > - DMA_FROM_DEVICE); > > + struct sgiseeq_private *sp = netdev_priv(dev); > > + > > + dma_sync_single_for_cpu(dev->dev.parent, VIRT_TO_DMA(sp, addr), > > + sizeof(struct sgiseeq_rx_desc), DMA_BIDIRECTIONAL); > > } > > > > static inline void dma_sync_desc_dev(struct net_device *dev, void *addr) > > { > > - dma_cache_sync(dev->dev.parent, addr, sizeof(struct sgiseeq_rx_desc), > > - DMA_TO_DEVICE); > > + struct sgiseeq_private *sp = netdev_priv(dev); > > + > > + dma_sync_single_for_device(dev->dev.parent, VIRT_TO_DMA(sp, addr), > > + sizeof(struct sgiseeq_rx_desc), DMA_BIDIRECTIONAL); > > } > > this breaks ethernet on IP22 completely, but I haven't figured out why, yet. the problem is that dma_sync_single_for_cpu() doesn't flush anything for IP22, because it only flushes for CPUs which do speculation. So either MIPS arch_sync_dma_for_cpu() should always flush or sgiseeq needs to use a different sync funktion, when it wants to re-read descriptors from memory. Thomas. -- Crap can work. Given enough thrust pigs will fly, but it's not necessarily a good idea. [ RFC1925, 2.3 ] 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=-11.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=unavailable 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 C6EF7C433E7 for ; Tue, 1 Sep 2020 17:13:17 +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 9880C20767 for ; Tue, 1 Sep 2020 17:13:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="x/UE4B7H" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9880C20767 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=alpha.franken.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-nvme-bounces+linux-nvme=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-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=wWA/6mvorl3gaf3lsqJAVlOwXWVOVe4wQ2S7ZSkOJmc=; b=x/UE4B7HgnQczEF316H1yVXth YCULIwtAZ3u87BzHVWj55y5otGDyn4eQt+Y1AnEuM99mdHk6+gwwibe5j7LEGpks3fxnowQwFnirW 4yXEtnvHvfDxz4F2zNA9U517KavjvUtwaGLxGg/H9H8T8iqynqlL5TylcnsnbUBvxBvub3tTSoyCk yFDxgxk/WZvKM3cygQiqCkIo7RV9x5XcUo+JmO1aQiNcpGP+RxH030KrIwTGDpU6BIbHlaCyz5ItO YJq6bjgItzKHgbs+gNSwXJpJHP4ulC9PoA17Np75KPfKucqpABZBkEY+dCBJIfUqbQ2yIoQN3OBQ8 z8tjz1F8Q==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kD9qI-0002tW-II; Tue, 01 Sep 2020 17:13:10 +0000 Received: from elvis.franken.de ([193.175.24.41]) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kD9qF-0002sN-Ex; Tue, 01 Sep 2020 17:13:08 +0000 Received: from uucp (helo=alpha) by elvis.franken.de with local-bsmtp (Exim 3.36 #1) id 1kD9qC-0004aY-00; Tue, 01 Sep 2020 19:13:04 +0200 Received: by alpha.franken.de (Postfix, from userid 1000) id A3E0EC0E68; Tue, 1 Sep 2020 19:12:41 +0200 (CEST) Date: Tue, 1 Sep 2020 19:12:41 +0200 From: Thomas Bogendoerfer To: Christoph Hellwig Subject: Re: [PATCH 22/28] sgiseeq: convert from dma_cache_sync to dma_sync_single_for_device Message-ID: <20200901171241.GA20685@alpha.franken.de> References: <20200819065555.1802761-1-hch@lst.de> <20200819065555.1802761-23-hch@lst.de> <20200901152209.GA14288@alpha.franken.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200901152209.GA14288@alpha.franken.de> User-Agent: Mutt/1.5.23 (2014-03-12) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200901_131307_702418_C6F0BBF1 X-CRM114-Status: GOOD ( 21.57 ) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: alsa-devel@alsa-project.org, linux-ia64@vger.kernel.org, linux-doc@vger.kernel.org, nouveau@lists.freedesktop.org, linux-nvme@lists.infradead.org, linux-mips@vger.kernel.org, "James E.J. Bottomley" , linux-mm@kvack.org, Marek Szyprowski , linux-samsung-soc@vger.kernel.org, Joonyoung Shim , linux-scsi@vger.kernel.org, iommu@lists.linux-foundation.org, Ben Skeggs , Matt Porter , linux-media@vger.kernel.org, Tom Lendacky , Pawel Osciak , Mauro Carvalho Chehab , linux-arm-kernel@lists.infradead.org, linux-parisc@vger.kernel.org, netdev@vger.kernel.org, Seung-Woo Kim , linux-kernel@vger.kernel.org, Kyungmin Park Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On Tue, Sep 01, 2020 at 05:22:09PM +0200, Thomas Bogendoerfer wrote: > On Wed, Aug 19, 2020 at 08:55:49AM +0200, Christoph Hellwig wrote: > > Use the proper modern API to transfer cache ownership for incoherent DMA. > > > > Signed-off-by: Christoph Hellwig > > --- > > drivers/net/ethernet/seeq/sgiseeq.c | 12 ++++++++---- > > 1 file changed, 8 insertions(+), 4 deletions(-) > > > > diff --git a/drivers/net/ethernet/seeq/sgiseeq.c b/drivers/net/ethernet/seeq/sgiseeq.c > > index 39599bbb5d45b6..f91dae16d69a19 100644 > > --- a/drivers/net/ethernet/seeq/sgiseeq.c > > +++ b/drivers/net/ethernet/seeq/sgiseeq.c > > @@ -112,14 +112,18 @@ struct sgiseeq_private { > > > > static inline void dma_sync_desc_cpu(struct net_device *dev, void *addr) > > { > > - dma_cache_sync(dev->dev.parent, addr, sizeof(struct sgiseeq_rx_desc), > > - DMA_FROM_DEVICE); > > + struct sgiseeq_private *sp = netdev_priv(dev); > > + > > + dma_sync_single_for_cpu(dev->dev.parent, VIRT_TO_DMA(sp, addr), > > + sizeof(struct sgiseeq_rx_desc), DMA_BIDIRECTIONAL); > > } > > > > static inline void dma_sync_desc_dev(struct net_device *dev, void *addr) > > { > > - dma_cache_sync(dev->dev.parent, addr, sizeof(struct sgiseeq_rx_desc), > > - DMA_TO_DEVICE); > > + struct sgiseeq_private *sp = netdev_priv(dev); > > + > > + dma_sync_single_for_device(dev->dev.parent, VIRT_TO_DMA(sp, addr), > > + sizeof(struct sgiseeq_rx_desc), DMA_BIDIRECTIONAL); > > } > > this breaks ethernet on IP22 completely, but I haven't figured out why, yet. the problem is that dma_sync_single_for_cpu() doesn't flush anything for IP22, because it only flushes for CPUs which do speculation. So either MIPS arch_sync_dma_for_cpu() should always flush or sgiseeq needs to use a different sync funktion, when it wants to re-read descriptors from memory. Thomas. -- Crap can work. Given enough thrust pigs will fly, but it's not necessarily a good idea. [ RFC1925, 2.3 ] _______________________________________________ Linux-nvme mailing list Linux-nvme@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-nvme 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=-11.5 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable 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 B86BDC433E6 for ; Tue, 1 Sep 2020 17:14:15 +0000 (UTC) Received: from alsa0.perex.cz (alsa0.perex.cz [77.48.224.243]) (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 3ED102078B for ; Tue, 1 Sep 2020 17:14:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=alsa-project.org header.i=@alsa-project.org header.b="cKqKSUC6" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3ED102078B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=alpha.franken.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=alsa-devel-bounces@alsa-project.org Received: from alsa1.perex.cz (alsa1.perex.cz [207.180.221.201]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by alsa0.perex.cz (Postfix) with ESMTPS id B10C316BF; Tue, 1 Sep 2020 19:13:23 +0200 (CEST) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa0.perex.cz B10C316BF DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=alsa-project.org; s=default; t=1598980453; bh=3AgNuDAjlaZT+/Ucz1j7Yd10nfiLbsKScGKLsPKiJNw=; h=Date:From:To:Subject:References:In-Reply-To:Cc:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: From; b=cKqKSUC6JsJtGRrld16Ie22yyPtriJErvqACySim1T9R5ieRzlMfZ8sNvYSO/j4yX Y6H+/58NAp5kTUefXj4SB+QF0HH6yDADOhWazvWoS0wG2L9vH6YsoQnPxc0/Y5HpO8 w/y5cmrg72W7c55Ls8cr7FaV1chuS/xbhtI/r+Jk= Received: from alsa1.perex.cz (localhost.localdomain [127.0.0.1]) by alsa1.perex.cz (Postfix) with ESMTP id 48C6EF8020D; Tue, 1 Sep 2020 19:13:23 +0200 (CEST) Received: by alsa1.perex.cz (Postfix, from userid 50401) id AA6B4F80217; Tue, 1 Sep 2020 19:13:20 +0200 (CEST) Received: from elvis.franken.de (elvis.franken.de [193.175.24.41]) by alsa1.perex.cz (Postfix) with ESMTP id 89F77F800BA for ; Tue, 1 Sep 2020 19:13:09 +0200 (CEST) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa1.perex.cz 89F77F800BA Received: from uucp (helo=alpha) by elvis.franken.de with local-bsmtp (Exim 3.36 #1) id 1kD9qC-0004aY-00; Tue, 01 Sep 2020 19:13:04 +0200 Received: by alpha.franken.de (Postfix, from userid 1000) id A3E0EC0E68; Tue, 1 Sep 2020 19:12:41 +0200 (CEST) Date: Tue, 1 Sep 2020 19:12:41 +0200 From: Thomas Bogendoerfer To: Christoph Hellwig Subject: Re: [PATCH 22/28] sgiseeq: convert from dma_cache_sync to dma_sync_single_for_device Message-ID: <20200901171241.GA20685@alpha.franken.de> References: <20200819065555.1802761-1-hch@lst.de> <20200819065555.1802761-23-hch@lst.de> <20200901152209.GA14288@alpha.franken.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200901152209.GA14288@alpha.franken.de> User-Agent: Mutt/1.5.23 (2014-03-12) Cc: alsa-devel@alsa-project.org, linux-ia64@vger.kernel.org, linux-doc@vger.kernel.org, nouveau@lists.freedesktop.org, linux-nvme@lists.infradead.org, linux-mips@vger.kernel.org, "James E.J. Bottomley" , linux-mm@kvack.org, Marek Szyprowski , linux-samsung-soc@vger.kernel.org, Joonyoung Shim , linux-scsi@vger.kernel.org, iommu@lists.linux-foundation.org, Ben Skeggs , Matt Porter , linux-media@vger.kernel.org, Tom Lendacky , Pawel Osciak , Mauro Carvalho Chehab , linux-arm-kernel@lists.infradead.org, linux-parisc@vger.kernel.org, netdev@vger.kernel.org, Seung-Woo Kim , linux-kernel@vger.kernel.org, Kyungmin Park X-BeenThere: alsa-devel@alsa-project.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: "Alsa-devel mailing list for ALSA developers - http://www.alsa-project.org" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: "Alsa-devel" On Tue, Sep 01, 2020 at 05:22:09PM +0200, Thomas Bogendoerfer wrote: > On Wed, Aug 19, 2020 at 08:55:49AM +0200, Christoph Hellwig wrote: > > Use the proper modern API to transfer cache ownership for incoherent DMA. > > > > Signed-off-by: Christoph Hellwig > > --- > > drivers/net/ethernet/seeq/sgiseeq.c | 12 ++++++++---- > > 1 file changed, 8 insertions(+), 4 deletions(-) > > > > diff --git a/drivers/net/ethernet/seeq/sgiseeq.c b/drivers/net/ethernet/seeq/sgiseeq.c > > index 39599bbb5d45b6..f91dae16d69a19 100644 > > --- a/drivers/net/ethernet/seeq/sgiseeq.c > > +++ b/drivers/net/ethernet/seeq/sgiseeq.c > > @@ -112,14 +112,18 @@ struct sgiseeq_private { > > > > static inline void dma_sync_desc_cpu(struct net_device *dev, void *addr) > > { > > - dma_cache_sync(dev->dev.parent, addr, sizeof(struct sgiseeq_rx_desc), > > - DMA_FROM_DEVICE); > > + struct sgiseeq_private *sp = netdev_priv(dev); > > + > > + dma_sync_single_for_cpu(dev->dev.parent, VIRT_TO_DMA(sp, addr), > > + sizeof(struct sgiseeq_rx_desc), DMA_BIDIRECTIONAL); > > } > > > > static inline void dma_sync_desc_dev(struct net_device *dev, void *addr) > > { > > - dma_cache_sync(dev->dev.parent, addr, sizeof(struct sgiseeq_rx_desc), > > - DMA_TO_DEVICE); > > + struct sgiseeq_private *sp = netdev_priv(dev); > > + > > + dma_sync_single_for_device(dev->dev.parent, VIRT_TO_DMA(sp, addr), > > + sizeof(struct sgiseeq_rx_desc), DMA_BIDIRECTIONAL); > > } > > this breaks ethernet on IP22 completely, but I haven't figured out why, yet. the problem is that dma_sync_single_for_cpu() doesn't flush anything for IP22, because it only flushes for CPUs which do speculation. So either MIPS arch_sync_dma_for_cpu() should always flush or sgiseeq needs to use a different sync funktion, when it wants to re-read descriptors from memory. Thomas. -- Crap can work. Given enough thrust pigs will fly, but it's not necessarily a good idea. [ RFC1925, 2.3 ] From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Bogendoerfer Subject: Re: [PATCH 22/28] sgiseeq: convert from dma_cache_sync to dma_sync_single_for_device Date: Tue, 1 Sep 2020 19:12:41 +0200 Message-ID: <20200901171241.GA20685@alpha.franken.de> References: <20200819065555.1802761-1-hch@lst.de> <20200819065555.1802761-23-hch@lst.de> <20200901152209.GA14288@alpha.franken.de> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <20200901152209.GA14288-I1c7kopa9pxLokYuJOExCg@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Sender: "iommu" To: Christoph Hellwig Cc: alsa-devel-K7yf7f+aM1XWsZ/bQMPhNw@public.gmane.org, linux-ia64-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-doc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, nouveau-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org, linux-nvme-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-mips-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, "James E.J. Bottomley" , linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, linux-samsung-soc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Joonyoung Shim , linux-scsi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, Ben Skeggs , Matt Porter , linux-media-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Tom Lendacky , Pawel Osciak , Mauro Carvalho Chehab , linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-parisc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Seung-Woo Kim , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Kyungmin Park List-Id: nouveau.vger.kernel.org On Tue, Sep 01, 2020 at 05:22:09PM +0200, Thomas Bogendoerfer wrote: > On Wed, Aug 19, 2020 at 08:55:49AM +0200, Christoph Hellwig wrote: > > Use the proper modern API to transfer cache ownership for incoherent DMA. > > > > Signed-off-by: Christoph Hellwig > > --- > > drivers/net/ethernet/seeq/sgiseeq.c | 12 ++++++++---- > > 1 file changed, 8 insertions(+), 4 deletions(-) > > > > diff --git a/drivers/net/ethernet/seeq/sgiseeq.c b/drivers/net/ethernet/seeq/sgiseeq.c > > index 39599bbb5d45b6..f91dae16d69a19 100644 > > --- a/drivers/net/ethernet/seeq/sgiseeq.c > > +++ b/drivers/net/ethernet/seeq/sgiseeq.c > > @@ -112,14 +112,18 @@ struct sgiseeq_private { > > > > static inline void dma_sync_desc_cpu(struct net_device *dev, void *addr) > > { > > - dma_cache_sync(dev->dev.parent, addr, sizeof(struct sgiseeq_rx_desc), > > - DMA_FROM_DEVICE); > > + struct sgiseeq_private *sp = netdev_priv(dev); > > + > > + dma_sync_single_for_cpu(dev->dev.parent, VIRT_TO_DMA(sp, addr), > > + sizeof(struct sgiseeq_rx_desc), DMA_BIDIRECTIONAL); > > } > > > > static inline void dma_sync_desc_dev(struct net_device *dev, void *addr) > > { > > - dma_cache_sync(dev->dev.parent, addr, sizeof(struct sgiseeq_rx_desc), > > - DMA_TO_DEVICE); > > + struct sgiseeq_private *sp = netdev_priv(dev); > > + > > + dma_sync_single_for_device(dev->dev.parent, VIRT_TO_DMA(sp, addr), > > + sizeof(struct sgiseeq_rx_desc), DMA_BIDIRECTIONAL); > > } > > this breaks ethernet on IP22 completely, but I haven't figured out why, yet. the problem is that dma_sync_single_for_cpu() doesn't flush anything for IP22, because it only flushes for CPUs which do speculation. So either MIPS arch_sync_dma_for_cpu() should always flush or sgiseeq needs to use a different sync funktion, when it wants to re-read descriptors from memory. Thomas. -- Crap can work. Given enough thrust pigs will fly, but it's not necessarily a good idea. [ RFC1925, 2.3 ] 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=-11.5 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 4DA24C433E7 for ; Tue, 1 Sep 2020 17:13:11 +0000 (UTC) Received: from hemlock.osuosl.org (smtp2.osuosl.org [140.211.166.133]) (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 29EC320767 for ; Tue, 1 Sep 2020 17:13:10 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 29EC320767 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=alpha.franken.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by hemlock.osuosl.org (Postfix) with ESMTP id D95CB870C4; Tue, 1 Sep 2020 17:13:10 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from hemlock.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id d6Ab9POMJo-6; Tue, 1 Sep 2020 17:13:10 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by hemlock.osuosl.org (Postfix) with ESMTP id 3255A8708C; Tue, 1 Sep 2020 17:13:10 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 280FBC07FF; Tue, 1 Sep 2020 17:13:10 +0000 (UTC) Received: from fraxinus.osuosl.org (smtp4.osuosl.org [140.211.166.137]) by lists.linuxfoundation.org (Postfix) with ESMTP id 9BFABC0051 for ; Tue, 1 Sep 2020 17:13:08 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by fraxinus.osuosl.org (Postfix) with ESMTP id 983A086155 for ; Tue, 1 Sep 2020 17:13:08 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from fraxinus.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id EkraXY4yKSNG for ; Tue, 1 Sep 2020 17:13:07 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from elvis.franken.de (elvis.franken.de [193.175.24.41]) by fraxinus.osuosl.org (Postfix) with ESMTP id D664785082 for ; Tue, 1 Sep 2020 17:13:06 +0000 (UTC) Received: from uucp (helo=alpha) by elvis.franken.de with local-bsmtp (Exim 3.36 #1) id 1kD9qC-0004aY-00; Tue, 01 Sep 2020 19:13:04 +0200 Received: by alpha.franken.de (Postfix, from userid 1000) id A3E0EC0E68; Tue, 1 Sep 2020 19:12:41 +0200 (CEST) Date: Tue, 1 Sep 2020 19:12:41 +0200 From: Thomas Bogendoerfer To: Christoph Hellwig Subject: Re: [PATCH 22/28] sgiseeq: convert from dma_cache_sync to dma_sync_single_for_device Message-ID: <20200901171241.GA20685@alpha.franken.de> References: <20200819065555.1802761-1-hch@lst.de> <20200819065555.1802761-23-hch@lst.de> <20200901152209.GA14288@alpha.franken.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200901152209.GA14288@alpha.franken.de> User-Agent: Mutt/1.5.23 (2014-03-12) Cc: alsa-devel@alsa-project.org, linux-ia64@vger.kernel.org, linux-doc@vger.kernel.org, nouveau@lists.freedesktop.org, linux-nvme@lists.infradead.org, linux-mips@vger.kernel.org, "James E.J. Bottomley" , linux-mm@kvack.org, linux-samsung-soc@vger.kernel.org, Joonyoung Shim , linux-scsi@vger.kernel.org, iommu@lists.linux-foundation.org, Ben Skeggs , Matt Porter , linux-media@vger.kernel.org, Tom Lendacky , Pawel Osciak , Mauro Carvalho Chehab , linux-arm-kernel@lists.infradead.org, linux-parisc@vger.kernel.org, netdev@vger.kernel.org, Seung-Woo Kim , linux-kernel@vger.kernel.org, Kyungmin Park X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" On Tue, Sep 01, 2020 at 05:22:09PM +0200, Thomas Bogendoerfer wrote: > On Wed, Aug 19, 2020 at 08:55:49AM +0200, Christoph Hellwig wrote: > > Use the proper modern API to transfer cache ownership for incoherent DMA. > > > > Signed-off-by: Christoph Hellwig > > --- > > drivers/net/ethernet/seeq/sgiseeq.c | 12 ++++++++---- > > 1 file changed, 8 insertions(+), 4 deletions(-) > > > > diff --git a/drivers/net/ethernet/seeq/sgiseeq.c b/drivers/net/ethernet/seeq/sgiseeq.c > > index 39599bbb5d45b6..f91dae16d69a19 100644 > > --- a/drivers/net/ethernet/seeq/sgiseeq.c > > +++ b/drivers/net/ethernet/seeq/sgiseeq.c > > @@ -112,14 +112,18 @@ struct sgiseeq_private { > > > > static inline void dma_sync_desc_cpu(struct net_device *dev, void *addr) > > { > > - dma_cache_sync(dev->dev.parent, addr, sizeof(struct sgiseeq_rx_desc), > > - DMA_FROM_DEVICE); > > + struct sgiseeq_private *sp = netdev_priv(dev); > > + > > + dma_sync_single_for_cpu(dev->dev.parent, VIRT_TO_DMA(sp, addr), > > + sizeof(struct sgiseeq_rx_desc), DMA_BIDIRECTIONAL); > > } > > > > static inline void dma_sync_desc_dev(struct net_device *dev, void *addr) > > { > > - dma_cache_sync(dev->dev.parent, addr, sizeof(struct sgiseeq_rx_desc), > > - DMA_TO_DEVICE); > > + struct sgiseeq_private *sp = netdev_priv(dev); > > + > > + dma_sync_single_for_device(dev->dev.parent, VIRT_TO_DMA(sp, addr), > > + sizeof(struct sgiseeq_rx_desc), DMA_BIDIRECTIONAL); > > } > > this breaks ethernet on IP22 completely, but I haven't figured out why, yet. the problem is that dma_sync_single_for_cpu() doesn't flush anything for IP22, because it only flushes for CPUs which do speculation. So either MIPS arch_sync_dma_for_cpu() should always flush or sgiseeq needs to use a different sync funktion, when it wants to re-read descriptors from memory. Thomas. -- Crap can work. Given enough thrust pigs will fly, but it's not necessarily a good idea. [ RFC1925, 2.3 ] _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu 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=-11.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=unavailable 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 4FAAFC433E6 for ; Tue, 1 Sep 2020 17:14:38 +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 1CC6220767 for ; Tue, 1 Sep 2020 17:14:38 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="oM+dJYjP" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1CC6220767 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=alpha.franken.de 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-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=FG0y1XWFqFh9hVRwYD81K82k8KxcPLllN0EIBnmLTEM=; b=oM+dJYjPNvYc+wDpAv0hAkD8Z FaHusuXPOs95nWHkVw0hGW/t7i7jehKZNHZXG7+DN9mhMEQTANfSqwNtAk/gMo0eCGsnAXD3w0HMd HSD8/iDGA0Hx+vk92uat1PNGajmJBYuDaEqfuKA2NFeyu2+pn8ELVkIjQ+J6/pZSsqeaCuAgzsmhO naLn50lkQyJ0Y/eR6hchQZllLJgUGvcU1mDR+iX+KtBykZqwQZbhNvo7oSJRjUQJa40ExIvvKbY+3 rbqpXU+V64hn3c3b3F3XqtAki0ho64aGs0m0Bp8eG51/5t7U7KRxV4i/nt+qF0m7lO7ErNDOwTBrg f4StMAZ2Q==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kD9qJ-0002tw-NK; Tue, 01 Sep 2020 17:13:11 +0000 Received: from elvis.franken.de ([193.175.24.41]) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kD9qF-0002sN-Ex; Tue, 01 Sep 2020 17:13:08 +0000 Received: from uucp (helo=alpha) by elvis.franken.de with local-bsmtp (Exim 3.36 #1) id 1kD9qC-0004aY-00; Tue, 01 Sep 2020 19:13:04 +0200 Received: by alpha.franken.de (Postfix, from userid 1000) id A3E0EC0E68; Tue, 1 Sep 2020 19:12:41 +0200 (CEST) Date: Tue, 1 Sep 2020 19:12:41 +0200 From: Thomas Bogendoerfer To: Christoph Hellwig Subject: Re: [PATCH 22/28] sgiseeq: convert from dma_cache_sync to dma_sync_single_for_device Message-ID: <20200901171241.GA20685@alpha.franken.de> References: <20200819065555.1802761-1-hch@lst.de> <20200819065555.1802761-23-hch@lst.de> <20200901152209.GA14288@alpha.franken.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200901152209.GA14288@alpha.franken.de> User-Agent: Mutt/1.5.23 (2014-03-12) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200901_131307_702418_C6F0BBF1 X-CRM114-Status: GOOD ( 21.57 ) 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: alsa-devel@alsa-project.org, linux-ia64@vger.kernel.org, linux-doc@vger.kernel.org, nouveau@lists.freedesktop.org, linux-nvme@lists.infradead.org, linux-mips@vger.kernel.org, "James E.J. Bottomley" , linux-mm@kvack.org, Marek Szyprowski , linux-samsung-soc@vger.kernel.org, Joonyoung Shim , linux-scsi@vger.kernel.org, iommu@lists.linux-foundation.org, Ben Skeggs , Matt Porter , linux-media@vger.kernel.org, Tom Lendacky , Pawel Osciak , Mauro Carvalho Chehab , linux-arm-kernel@lists.infradead.org, linux-parisc@vger.kernel.org, netdev@vger.kernel.org, Seung-Woo Kim , linux-kernel@vger.kernel.org, Kyungmin Park Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, Sep 01, 2020 at 05:22:09PM +0200, Thomas Bogendoerfer wrote: > On Wed, Aug 19, 2020 at 08:55:49AM +0200, Christoph Hellwig wrote: > > Use the proper modern API to transfer cache ownership for incoherent DMA. > > > > Signed-off-by: Christoph Hellwig > > --- > > drivers/net/ethernet/seeq/sgiseeq.c | 12 ++++++++---- > > 1 file changed, 8 insertions(+), 4 deletions(-) > > > > diff --git a/drivers/net/ethernet/seeq/sgiseeq.c b/drivers/net/ethernet/seeq/sgiseeq.c > > index 39599bbb5d45b6..f91dae16d69a19 100644 > > --- a/drivers/net/ethernet/seeq/sgiseeq.c > > +++ b/drivers/net/ethernet/seeq/sgiseeq.c > > @@ -112,14 +112,18 @@ struct sgiseeq_private { > > > > static inline void dma_sync_desc_cpu(struct net_device *dev, void *addr) > > { > > - dma_cache_sync(dev->dev.parent, addr, sizeof(struct sgiseeq_rx_desc), > > - DMA_FROM_DEVICE); > > + struct sgiseeq_private *sp = netdev_priv(dev); > > + > > + dma_sync_single_for_cpu(dev->dev.parent, VIRT_TO_DMA(sp, addr), > > + sizeof(struct sgiseeq_rx_desc), DMA_BIDIRECTIONAL); > > } > > > > static inline void dma_sync_desc_dev(struct net_device *dev, void *addr) > > { > > - dma_cache_sync(dev->dev.parent, addr, sizeof(struct sgiseeq_rx_desc), > > - DMA_TO_DEVICE); > > + struct sgiseeq_private *sp = netdev_priv(dev); > > + > > + dma_sync_single_for_device(dev->dev.parent, VIRT_TO_DMA(sp, addr), > > + sizeof(struct sgiseeq_rx_desc), DMA_BIDIRECTIONAL); > > } > > this breaks ethernet on IP22 completely, but I haven't figured out why, yet. the problem is that dma_sync_single_for_cpu() doesn't flush anything for IP22, because it only flushes for CPUs which do speculation. So either MIPS arch_sync_dma_for_cpu() should always flush or sgiseeq needs to use a different sync funktion, when it wants to re-read descriptors from memory. Thomas. -- Crap can work. Given enough thrust pigs will fly, but it's not necessarily a good idea. [ RFC1925, 2.3 ] _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Bogendoerfer Date: Tue, 01 Sep 2020 17:12:41 +0000 Subject: Re: [PATCH 22/28] sgiseeq: convert from dma_cache_sync to dma_sync_single_for_device Message-Id: <20200901171241.GA20685@alpha.franken.de> List-Id: References: <20200819065555.1802761-1-hch@lst.de> <20200819065555.1802761-23-hch@lst.de> <20200901152209.GA14288@alpha.franken.de> In-Reply-To: <20200901152209.GA14288@alpha.franken.de> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Christoph Hellwig Cc: alsa-devel@alsa-project.org, linux-ia64@vger.kernel.org, linux-doc@vger.kernel.org, nouveau@lists.freedesktop.org, linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org, "James E.J. Bottomley" , linux-mm@kvack.org, Marek Szyprowski , linux-samsung-soc@vger.kernel.org, Joonyoung Shim , linux-scsi@vger.kernel.org, Kyungmin Park , Ben Skeggs , Matt Porter , linux-media@vger.kernel.org, Tom Lendacky , Pawel Osciak , Mauro Carvalho Chehab , linux-arm-kernel@lists.infradead.org, linux-parisc@vger.kernel.org, netdev@vger.kernel.org, Seung-Woo Kim , linux-mips@vger.kernel.org, iommu@lists.linux-foundation.org On Tue, Sep 01, 2020 at 05:22:09PM +0200, Thomas Bogendoerfer wrote: > On Wed, Aug 19, 2020 at 08:55:49AM +0200, Christoph Hellwig wrote: > > Use the proper modern API to transfer cache ownership for incoherent DMA. > > > > Signed-off-by: Christoph Hellwig > > --- > > drivers/net/ethernet/seeq/sgiseeq.c | 12 ++++++++---- > > 1 file changed, 8 insertions(+), 4 deletions(-) > > > > diff --git a/drivers/net/ethernet/seeq/sgiseeq.c b/drivers/net/ethernet/seeq/sgiseeq.c > > index 39599bbb5d45b6..f91dae16d69a19 100644 > > --- a/drivers/net/ethernet/seeq/sgiseeq.c > > +++ b/drivers/net/ethernet/seeq/sgiseeq.c > > @@ -112,14 +112,18 @@ struct sgiseeq_private { > > > > static inline void dma_sync_desc_cpu(struct net_device *dev, void *addr) > > { > > - dma_cache_sync(dev->dev.parent, addr, sizeof(struct sgiseeq_rx_desc), > > - DMA_FROM_DEVICE); > > + struct sgiseeq_private *sp = netdev_priv(dev); > > + > > + dma_sync_single_for_cpu(dev->dev.parent, VIRT_TO_DMA(sp, addr), > > + sizeof(struct sgiseeq_rx_desc), DMA_BIDIRECTIONAL); > > } > > > > static inline void dma_sync_desc_dev(struct net_device *dev, void *addr) > > { > > - dma_cache_sync(dev->dev.parent, addr, sizeof(struct sgiseeq_rx_desc), > > - DMA_TO_DEVICE); > > + struct sgiseeq_private *sp = netdev_priv(dev); > > + > > + dma_sync_single_for_device(dev->dev.parent, VIRT_TO_DMA(sp, addr), > > + sizeof(struct sgiseeq_rx_desc), DMA_BIDIRECTIONAL); > > } > > this breaks ethernet on IP22 completely, but I haven't figured out why, yet. the problem is that dma_sync_single_for_cpu() doesn't flush anything for IP22, because it only flushes for CPUs which do speculation. So either MIPS arch_sync_dma_for_cpu() should always flush or sgiseeq needs to use a different sync funktion, when it wants to re-read descriptors from memory. Thomas. -- Crap can work. Given enough thrust pigs will fly, but it's not necessarily a good idea. [ RFC1925, 2.3 ]