From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: virtio-comment-return-609-cohuck=redhat.com@lists.oasis-open.org Sender: List-Post: List-Help: List-Unsubscribe: List-Subscribe: Received: from lists.oasis-open.org (oasis.ws5.connectedcommunity.org [10.110.1.242]) by lists.oasis-open.org (Postfix) with ESMTP id 1E41C985B66 for ; Wed, 13 Feb 2019 16:52:47 +0000 (UTC) Date: Wed, 13 Feb 2019 16:52:30 +0000 From: "Dr. David Alan Gilbert" Message-ID: <20190213165230.GE2601@work-vm> References: <20190111114200.10026-1-dgilbert@redhat.com> <20190111114200.10026-4-dgilbert@redhat.com> <20190213023352.GD14307@stefanha-x1.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190213023352.GD14307@stefanha-x1.localdomain> Subject: Re: [virtio-comment] Re: [PATCH 3/3] shared memory: Define mmio registers To: Stefan Hajnoczi Cc: virtio-comment@lists.oasis-open.org List-ID: * Stefan Hajnoczi (stefanha@redhat.com) wrote: > On Fri, Jan 11, 2019 at 11:42:00AM +0000, Dr. David Alan Gilbert (git) wrote: > > diff --git a/content.tex b/content.tex > > index 776162a..e2435ff 100644 > > --- a/content.tex > > +++ b/content.tex > > @@ -1641,6 +1641,33 @@ All register values are organized as Little Endian. > > selected by writing to \field{QueueSel}. > > } > > \hline > > + \mmioreg{SHMSel}{Shared memory region select}{0x0b0}{W}{% > > + Writing to this register selects the shared memory region \ref{sec:Basic Facilities of a Virtio Device / Shared Memory Regions} > > + following operations on \field{SHMId}, \field{SHMLenLow}, \field{SHMLenHigh}, > > + \field{SHMBaseLow} and \field{SHMBaseHigh} apply to. The index > > + number of the first region is zero (0x0); note that it is a > > + simple index that does not correspond to the \field{id}. > > Why use a separate virtio-mmio index instead of the shared memory ID? > The driver would map those IDs it knows about, so I'm not sure if > enumerating them via a separate index is useful. Plus using the ID lets > you drop one register from the interface. Yes, I think if we don't need enumeration that's right; we just shange SHMId to be the writeable register and drop the SHMSel register. Dave -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK This publicly archived list offers a means to provide input to the OASIS Virtual I/O Device (VIRTIO) TC. In order to verify user consent to the Feedback License terms and to minimize spam in the list archive, subscription is required before posting. Subscribe: virtio-comment-subscribe@lists.oasis-open.org Unsubscribe: virtio-comment-unsubscribe@lists.oasis-open.org List help: virtio-comment-help@lists.oasis-open.org List archive: https://lists.oasis-open.org/archives/virtio-comment/ Feedback License: https://www.oasis-open.org/who/ipr/feedback_license.pdf List Guidelines: https://www.oasis-open.org/policies-guidelines/mailing-lists Committee: https://www.oasis-open.org/committees/virtio/ Join OASIS: https://www.oasis-open.org/join/