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 D3DEBA052A; Tue, 26 Jan 2021 11:45:04 +0100 (CET) Received: from [217.70.189.124] (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 8B0581413E5; Tue, 26 Jan 2021 11:45:04 +0100 (CET) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [63.128.21.124]) by mails.dpdk.org (Postfix) with ESMTP id 68B971413DF for ; Tue, 26 Jan 2021 11:45:01 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1611657900; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=UgAHoacoC0oBo9To2r3glGF3jUsf60ilQzh4bhEtmU0=; b=Ah2JS84bK/z6nprFDadPBpOraiJQFoId1Bu+0Pk/u2hz6eshOsh1/Gy6ZInW8jniciZgwr ACbkTSHz2QICzvTBIycRrmE9eqkv3kr2j2P6WvFIkwQX4IGbp+JP5GO3wod8bavqafTe/B E4kYo3qOj7Cko1ljeDFOOMhhAYaG0y8= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-502-m7NXhHwuOcigNiIGHFY1PA-1; Tue, 26 Jan 2021 05:44:56 -0500 X-MC-Unique: m7NXhHwuOcigNiIGHFY1PA-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 3355C1007394; Tue, 26 Jan 2021 10:44:55 +0000 (UTC) Received: from [10.36.110.31] (unknown [10.36.110.31]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 6AE5A1F466; Tue, 26 Jan 2021 10:44:23 +0000 (UTC) To: =?UTF-8?B?6LCi5Y2O5LyfKOatpOaXtuatpOWIu++8iQ==?= , 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> <9b614cce-8e41-9ed6-a648-fbbe3fc14807@alibaba-inc.com> From: Maxime Coquelin Message-ID: <71352868-a699-d876-25c3-b36df4f8649f@redhat.com> Date: Tue, 26 Jan 2021 11:44:21 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.6.0 MIME-Version: 1.0 In-Reply-To: <9b614cce-8e41-9ed6-a648-fbbe3fc14807@alibaba-inc.com> X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=maxime.coquelin@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit 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 1/22/21 8:25 AM, 谢华伟(此时此刻） 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. OK, that makes sense. I am OK with keeping patch 2, but would like Ferruh's ACK. Could you please post v6? Thanks, Maxime >> >> 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 >> >