From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: <dev-bounces@dpdk.org> Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id AB35DA052A; Tue, 26 Jan 2021 13:31:02 +0100 (CET) Received: from [217.70.189.124] (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 23914141481; Tue, 26 Jan 2021 13:31:02 +0100 (CET) Received: from out0-155.mail.aliyun.com (out0-155.mail.aliyun.com [140.205.0.155]) by mails.dpdk.org (Postfix) with ESMTP id 8637A14141D for <dev@dpdk.org>; Tue, 26 Jan 2021 13:31:00 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alibaba-inc.com; s=default; t=1611664258; h=Subject:From:To:Message-ID:Date:MIME-Version:Content-Type; bh=QC62UIMz+cQdvnzH8eAUYqZrcR/z1jcAs9pXJ0h7dRs=; b=GScd5DDoecAYpo/zP08tGtwK26p4YjsoDWPfQ+/fAeUzBBApNg0HHCrO+qmOYMzn4oph+np2xZpmX3mXP/R/6crgADU777STPXazdsxHow0Gl/a+63IRuFWG/MXoEx+gC7bcsFbEVrkALU3sbHqNYAF6bQqgGkv29opYQTazNaM= X-Alimail-AntiSpam: AC=PASS; BC=-1|-1; BR=01201311R151e4; CH=green; DM=||false|; DS=||; FP=0|-1|-1|-1|0|-1|-1|-1; HT=ay29a033018047190; MF=huawei.xhw@alibaba-inc.com; NM=1; PH=DS; RN=9; SR=0; TI=SMTPD_---.JQZFxRN_1611664257; Received: from 30.43.72.133(mailfrom:huawei.xhw@alibaba-inc.com fp:SMTPD_---.JQZFxRN_1611664257) by smtp.aliyun-inc.com(127.0.0.1); Tue, 26 Jan 2021 20:30:57 +0800 From: "=?UTF-8?B?6LCi5Y2O5LyfKOatpOaXtuatpOWIu++8iQ==?=" <huawei.xhw@alibaba-inc.com> To: Maxime Coquelin <maxime.coquelin@redhat.com>, 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, "Xueming(Steven) Li" <xuemingl@nvidia.com> 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> <fb903a81-a032-3300-29f9-218164fe8e56@redhat.com> <e5d7e73e-58c8-4820-85f4-ee9a8e90064f@redhat.com> <18871462-4d25-302a-2716-99ebec65c3ac@alibaba-inc.com> <e24f7bfd-e071-0b51-bbc9-21e0b61a69cf@redhat.com> <40e0702d-7847-9dc3-1904-03a7b8e92c2e@alibaba-inc.com> <3c83a06d-c757-e470-441b-a8b7f496a953@redhat.com> <9b614cce-8e41-9ed6-a648-fbbe3fc14807@alibaba-inc.com> Message-ID: <2d3d225c-0645-7a8b-9f26-e8e9d91cea9a@alibaba-inc.com> Date: Tue, 26 Jan 2021 20:30:52 +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: <9b614cce-8e41-9ed6-a648-fbbe3fc14807@alibaba-inc.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 <dev.dpdk.org> List-Unsubscribe: <https://mails.dpdk.org/options/dev>, <mailto:dev-request@dpdk.org?subject=unsubscribe> List-Archive: <http://mails.dpdk.org/archives/dev/> List-Post: <mailto:dev@dpdk.org> List-Help: <mailto:dev-request@dpdk.org?subject=help> List-Subscribe: <https://mails.dpdk.org/listinfo/dev>, <mailto:dev-request@dpdk.org?subject=subscribe> Errors-To: dev-bounces@dpdk.org Sender: "dev" <dev-bounces@dpdk.org> On 2021/1/22 15:25, chris wrote: > > 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 >> Hi Maxime: Decision on patch 2? I still think current patch 2 is cleaner. Thanks, huawei >> Maxime >>