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=-3.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 4C969C4363A for ; Wed, 28 Oct 2020 22:19:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 003DC206D9 for ; Wed, 28 Oct 2020 22:19:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603923588; bh=RJ9ykVp5/VBMVYU2UaC4tSf7S71M609QGWBo1zd6fvU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=o9sKH5c7KxdDWXeOLYrAjBf9KhpZWCSWcxTggbkFd8QLZg9NfBpf7nPHr911xQz4b J07a3P+J/YeYLUnar5DIZnLdC0zwMeFZZhGDd9fa2my6Kb1gfDtKJp5cIC1XWWW6/F NS5Aaid+GN0ZIh9ra0pCYHcNDRNRPhlfcQgIhsGc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732026AbgJ1WTq (ORCPT ); Wed, 28 Oct 2020 18:19:46 -0400 Received: from mail.kernel.org ([198.145.29.99]:60510 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731783AbgJ1WRp (ORCPT ); Wed, 28 Oct 2020 18:17:45 -0400 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E4ABF246B1; Wed, 28 Oct 2020 11:12:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603883579; bh=RJ9ykVp5/VBMVYU2UaC4tSf7S71M609QGWBo1zd6fvU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=fJtEWKRDcVR3PZzvaXM6+dpyvhhGPlwT5TeHV8luPiDQWAA3aI6KJ21c1c4U4wSRu NjJNY5iYrVHN0iOpdRtyRyvQtkpDyovYKl4TVqWJmC/9be1nLEmgZ0mp7PpDpO3xe5 1WFpwyaAZ7KgaLhktVRT9qtImxzQIEEcLs92iTQs= Date: Wed, 28 Oct 2020 12:13:51 +0100 From: Greg KH To: Andy Duan Cc: Sherry Sun , "hch@infradead.org" , "vincent.whitchurch@axis.com" , "sudeep.dutt@intel.com" , "ashutosh.dixit@intel.com" , "arnd@arndb.de" , "kishon@ti.com" , "lorenzo.pieralisi@arm.com" , "linux-kernel@vger.kernel.org" , "linux-pci@vger.kernel.org" , dl-linux-imx Subject: Re: [EXT] Re: [PATCH V5 0/2] Change vring space from nomal memory to dma coherent memory Message-ID: <20201028111351.GA1964851@kroah.com> References: <20201028020305.10593-1-sherry.sun@nxp.com> <20201028055836.GA244690@kroah.com> <20201028070712.GA1649838@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Oct 28, 2020 at 10:17:39AM +0000, Andy Duan wrote: > From: Greg KH Sent: Wednesday, October 28, 2020 3:07 PM > > On Wed, Oct 28, 2020 at 06:05:28AM +0000, Sherry Sun wrote: > > > Hi Greg, > > > > > > > Subject: Re: [PATCH V5 0/2] Change vring space from nomal memory to > > > > dma coherent memory > > > > > > > > On Wed, Oct 28, 2020 at 10:03:03AM +0800, Sherry Sun wrote: > > > > > Changes in V5: > > > > > 1. Reorganize the vop_mmap function code in patch 1, which is done > > > > > by > > > > Christoph. > > > > > 2. Completely remove the unnecessary code related to reassign the > > > > > used ring for card in patch 2. > > > > > > > > > > The original vop driver only supports dma coherent device, as it > > > > > allocates and maps vring by _get_free_pages and dma_map_single, > > > > > but not use dma_sync_single_for_cpu/device to sync the updates of > > > > > device_page/vring between EP and RC, which will cause memory > > > > > synchronization problem for device don't support hardware dma coherent. > > > > > > > > > > And allocate vrings use dma_alloc_coherent is a common way in > > > > > kernel, as the memory interacted between two systems should use > > > > > consistent memory to avoid caching effects. So here add > > > > > noncoherent platform > > > > support for vop driver. > > > > > Also add some related dma changes to make sure noncoherent > > > > > platform works well. > > > > > > > > > > Sherry Sun (2): > > > > > misc: vop: change the way of allocating vrings and device page > > > > > misc: vop: do not allocate and reassign the used ring > > > > > > > > > > drivers/misc/mic/bus/vop_bus.h | 2 + > > > > > drivers/misc/mic/host/mic_boot.c | 9 ++ > > > > > drivers/misc/mic/host/mic_main.c | 43 ++------ > > > > > drivers/misc/mic/vop/vop_debugfs.c | 4 - > > > > > drivers/misc/mic/vop/vop_main.c | 70 +----------- > > > > > drivers/misc/mic/vop/vop_vringh.c | 166 ++++++++++------------------- > > > > > include/uapi/linux/mic_common.h | 9 +- > > > > > 7 files changed, 85 insertions(+), 218 deletions(-) > > > > > > > > Have you all seen: > > > > > > > > https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%25 > > > > > > 2Flore.kernel.org%2Fr%2F8c1443136563de34699d2c084df478181c205db4.16 > > > > > > 03854416.git.sudeep.dutt%40intel.com&data=04%7C01%7Csherry.sun% > > > > > > 40nxp.com%7Cc19c987667434969847e08d87b0685e8%7C686ea1d3bc2b4c6f > > > > > > a92cd99c5c301635%7C0%7C0%7C637394615238940323%7CUnknown%7CTW > > > > > > FpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJX > > > > > > VCI6Mn0%3D%7C1000&sdata=Zq%2FtHWTq%2BuIVBYXFGoeBmq0JJzYd > > > > 9zDyv4NVN4TpC%2FU%3D&reserved=0 > > > > > > > > Looks like this code is asking to just be deleted, is that ok with you? > > > > > > Yes, I saw that patch. I'm ok with it. > > > > Great, can you please provide a "Reviewed-by:" or "Acked-by:" for it? > > > > thanks, > > > > greg k-h > > Sherry took much effort on the features support on i.MX series like i.MX8QM/i.MX8QXP/i.MX8MM. > > Now it is a pity to delete the vop code. > > One question, > can we resubmit vop code by clean up, now only for i.MX series as Dutt's suggestion ? > Or we have to drop the design and switch to select other solutions ? If this whole subsystem is being deleted because it is not used and never shipped, yes, please use a different solution. I don't understand why you were trying to piggy-back on this codebase if the hardware was totally different, for some reason I thought this was the same hardware. What exactly is this? thanks, greg k-h