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 Received: from ws5-mx01.kavi.com (ws5-mx01.kavi.com [34.193.7.191]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A54FEC77B72 for ; Tue, 18 Apr 2023 01:09:45 +0000 (UTC) Received: from lists.oasis-open.org (oasis.ws5.connectedcommunity.org [10.110.1.242]) by ws5-mx01.kavi.com (Postfix) with ESMTP id E26E3603F0 for ; Tue, 18 Apr 2023 01:09:43 +0000 (UTC) Received: from lists.oasis-open.org (oasis-open.org [10.110.1.242]) by lists.oasis-open.org (Postfix) with ESMTP id 98625986434 for ; Tue, 18 Apr 2023 01:09:43 +0000 (UTC) Received: from host09.ws5.connectedcommunity.org (host09.ws5.connectedcommunity.org [10.110.1.97]) by lists.oasis-open.org (Postfix) with QMQP id 87A6F9863D9; Tue, 18 Apr 2023 01:09:43 +0000 (UTC) Mailing-List: contact virtio-dev-help@lists.oasis-open.org; run by ezmlm List-ID: Sender: Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: Received: from lists.oasis-open.org (oasis-open.org [10.110.1.242]) by lists.oasis-open.org (Postfix) with ESMTP id 738C998669C for ; Tue, 18 Apr 2023 01:09:43 +0000 (UTC) X-Virus-Scanned: amavisd-new at kavi.com X-MC-Unique: R7mn5pSSO7aAEXG_52KaSA-1 X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1681780180; x=1684372180; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=RIjBmB22Id2Kqr5ZlkoNTbHFtOm6iFNBFqaO4ORYTV8=; b=OHDlgdpXInpTP41TGeMW4K3B77m5ozPzoeiP7iVPtSv5IeFba6Q3JBMm6BPMBnZD/f twSkZM3175ISBETUwBPCDDRoZATzYOifvn6E5TSqCrao6uDnOrbL4sVS2epZql4W8Gn5 98kjYbDfyvfJxxQhEotWf/F2z4WA5MZHh6LCkk67315jGfmL8hL6pCXJ4bqh2lrMNu55 r2BgWyOdXk769uO1QITHJi+w7+qi5zpIosgc05TSni42SIi3816w6A7UMUGLNVgPTCvD lOCGz/C9v56onDzlMI4qbXzZ7nRVzh6cvLvJTDJ2nt0ixLJXm+IuK4SgnsqK4QyjpuGE TzUw== X-Gm-Message-State: AAQBX9e4pEgUbTrf/5cFLz4/F1DSFv1VQOChTimU/DckIhFTk41/eR95 EAcTLuzr9SDT9ZoTaL1RD4qswVAZeW2pvIAc77NOJt/QR1PV2gAdFLqfl6/nfE+0R94CEWFWL3J CUJRkKzSybV1wimWYfGy/if1XEsQIgEL+GtkbIt6nF5M4 X-Received: by 2002:a05:6808:1820:b0:38e:8cf:b1d6 with SMTP id bh32-20020a056808182000b0038e08cfb1d6mr202186oib.3.1681780180382; Mon, 17 Apr 2023 18:09:40 -0700 (PDT) X-Google-Smtp-Source: AKy350Y5186As3adoBSjM0ODuGJUEPSe1JJAz+a+LKjsTn/gsnTFW/c+7xFrzRRPjk9hNCtXtzC8s3MNpswMVdn5jgg= X-Received: by 2002:a05:6808:1820:b0:38e:8cf:b1d6 with SMTP id bh32-20020a056808182000b0038e08cfb1d6mr202177oib.3.1681780180151; Mon, 17 Apr 2023 18:09:40 -0700 (PDT) MIME-Version: 1.0 References: <20230413163216-mutt-send-email-mst@kernel.org> <20230414025523-mutt-send-email-mst@kernel.org> <20230416163929-mutt-send-email-mst@kernel.org> In-Reply-To: From: Jason Wang Date: Tue, 18 Apr 2023 09:09:29 +0800 Message-ID: To: Parav Pandit Cc: "Michael S. Tsirkin" , "virtio-dev@lists.oasis-open.org" , "cohuck@redhat.com" , "virtio-comment@lists.oasis-open.org" , Shahaf Shuler , Satananda Burla , Maxime Coquelin , Yan Vugenfirer X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Subject: [virtio-dev] Re: [virtio-comment] Re: [PATCH 09/11] transport-pci: Describe PCI MMR dev config registers On Tue, Apr 18, 2023 at 12:59=E2=80=AFAM Parav Pandit wr= ote: > > > > From: Michael S. Tsirkin > > Sent: Sunday, April 16, 2023 4:44 PM > > > > On Sun, Apr 16, 2023 at 01:41:55PM +0000, Parav Pandit wrote: > > > > From: virtio-comment@lists.oasis-open.org > > > > On Behalf Of Michael S. > > > > Tsirkin > > > > Sent: Friday, April 14, 2023 2:57 AM > > > > > > > Do you refer to the trick Jason proposed where BAR0 is memory but > > > > otherwise matches legacy BAR0 exactly? Is this your preferred solut= ion at > > this point then? > > > > > > We look at it again. > > > Above solution can work reliably only for a very small number of PF a= nd that > > too with very special hardware circuitry due to the reset flow. > > > > > > Therefore, for virtualization below interface is preferred. > > > a. For transitional device legacy configuration register transport > > > over AQ, > > > > I don't get what this has to do with transitional ... > > > Typically, in current wordings, transitional is the device that supports = legacy interface. > So, it doesn't have to be for the transitional. > > I just wanted to highlight that a PCI VF device with its parent PCI PF de= vice can transport the legacy interface commands. > > > > Notification to utilize transitional device notification area of the = BAR. > > > > The vq transport does something like this, no? > > > Notifications over a queuing interface unlikely can be a performant inter= face because one is configuration task and other is data path task. Note that current transport virtqueue only allows the notification via MMIO. It introduces a command to get the address of the notification area. Thanks > > > > b. Non legacy interface of transitional and non-transitional PCI devi= ce to > > access direct PCI device without mediation. > > > > So VF can either be accessed through AQ of PF, or through direct mappin= g? > Right. VF to access legacy registers using AQ of PF and continue non-lega= cy registers using direct mapping as done today. > --------------------------------------------------------------------- To unsubscribe, e-mail: virtio-dev-unsubscribe@lists.oasis-open.org For additional commands, e-mail: virtio-dev-help@lists.oasis-open.org