From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id E6D87A0A0A; Fri, 22 Jan 2021 08:25:22 +0100 (CET) Received: from [217.70.189.124] (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 7F693140CF8; Fri, 22 Jan 2021 08:25:22 +0100 (CET) Received: from out0-154.mail.aliyun.com (out0-154.mail.aliyun.com [140.205.0.154]) by mails.dpdk.org (Postfix) with ESMTP id 5FB86140CF7 for ; Fri, 22 Jan 2021 08:25:20 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alibaba-inc.com; s=default; t=1611300315; h=Subject:To:From:Message-ID:Date:MIME-Version:Content-Type; bh=F/qGIPyz0Ocv2fCPDiLGABXYdu4pYqVRMzm1yC4wLNM=; b=SDzbOVeBQZW+KO7Y4d1gSzDPc4VfnUpG9TSitEF26ge1R6Z9pEBWrIKJARWNvs15XL24JgwNPyr3DYWIwbgng//WEqCEgxCIYviYKb97FhtnuAK6kLEGawIj+Hvx3+czH35XCYcX4bsChzs61f7W6Xx08wabUQGVnUwTZaSMP/0= X-Alimail-AntiSpam: AC=PASS; BC=-1|-1; BR=01201311R801e4; CH=green; DM=||false|; DS=||; FP=0|-1|-1|-1|0|-1|-1|-1; HT=ay29a033018047212; MF=huawei.xhw@alibaba-inc.com; NM=1; PH=DS; RN=8; SR=0; TI=SMTPD_---.JOGuDUZ_1611300313; Received: from 30.43.73.156(mailfrom:huawei.xhw@alibaba-inc.com fp:SMTPD_---.JOGuDUZ_1611300313) by smtp.aliyun-inc.com(127.0.0.1); Fri, 22 Jan 2021 15:25:13 +0800 To: Maxime Coquelin , ferruh.yigit@intel.com Cc: dev@dpdk.org, anatoly.burakov@intel.com, david.marchand@redhat.com, zhihong.wang@intel.com, chenbo.xia@intel.com, grive@u256.net References: <68ecd941-9c56-4de7-fae2-2ad15bdfd81a@alibaba-inc.com> <1603381885-88819-1-git-send-email-huawei.xhw@alibaba-inc.com> <1603381885-88819-4-git-send-email-huawei.xhw@alibaba-inc.com> <18871462-4d25-302a-2716-99ebec65c3ac@alibaba-inc.com> <40e0702d-7847-9dc3-1904-03a7b8e92c2e@alibaba-inc.com> <3c83a06d-c757-e470-441b-a8b7f496a953@redhat.com> From: "=?UTF-8?B?6LCi5Y2O5LyfKOatpOaXtuatpOWIu++8iQ==?=" Message-ID: <9b614cce-8e41-9ed6-a648-fbbe3fc14807@alibaba-inc.com> Date: Fri, 22 Jan 2021 15:25:08 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.6.1 MIME-Version: 1.0 In-Reply-To: <3c83a06d-c757-e470-441b-a8b7f496a953@redhat.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US Subject: Re: [dpdk-dev] [PATCH v5 3/3] PCI: don't use vfio ioctl call to access PIO resource X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" On 2021/1/21 23:38, Maxime Coquelin wrote: >> Do you mean we apply or abandon patch 3? I am both OK. The first >> priority to me is to enable MMIO bar support. > OK, so yes, I think we should abandon patch 2 and patch 3. > For patch 1, it looks valid to me, but I'll let Ferruh decide. > > For your device, if my understanding is correct, what we need to do is > to support MMIO for legacy devices. Correct? yes. > If so, the change should be in virtio_pci.c. In vtpci_init(), after > modern detection has failed, we should check the the BAR is PIO or MMIO > based on the flag. the result can be saved in struct virtio_pci_dev. > > > We would introduce new wrappers like vtpci_legacy_read, > vtpci_legacy_write that would either call rte_pci_ioport_read, > rte_pci_ioport_read in case of PIO, or rte_read32, rte_write32 in case > of MMIO. There are two choices. 1, apply patch 2.     IO/MMIO port are mapped and accessed using the same API. Kernel is doing in the same way like the following.             io_addr = pci_iomap                 get PIO directly or ioremap             iowrite16/32(val, io_addr + offset) I think applying patch 2 is a correct choice. It is a fix. Driver had better not know if bar is PIO or MMIO.  ioport in ioport_xx API means IO, not PIO. Btw, it only affects virtio PMD,  not that intrusive.  2, virtio specific change to enable MMIO support. Comparing with choice 1, i feels it is not that clean and pretty. > > It is not too late for this release, as the change will not be that > intrusive. But if you prepare such patch, please base it on top of my > virtio rework series; To make it easier to you, I added it to the dpdk- > next-virtio tree: > https://git.dpdk.org/next/dpdk-next-virtio/log/?h=virtio_pmd_rework_v2 > > Thanks, > Maxime >