From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: virtio-return-3425-cohuck=redhat.com@lists.oasis-open.org Sender: List-Post: List-Help: List-Unsubscribe: List-Subscribe: Date: Tue, 3 Dec 2019 05:39:23 -0500 From: "Michael S. Tsirkin" Message-ID: <20191203103646.490868-1-mst@redhat.com> MIME-Version: 1.0 Subject: [virtio] [PATCH v3] content: document speed, duplex Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable Content-Disposition: inline To: virtio-comment@lists.oasis-open.org, virtio-dev@lists.oasis-open.org Cc: virtio@lists.oasis-open.org, Cornelia Huck List-ID: Document as used by Linux. Fixes: https://github.com/oasis-tcs/virtio-spec/issues/59 Signed-off-by: Michael S. Tsirkin Reviewed-by: Cornelia Huck --- changes from v2: =09fix up units =09actually there's no way for driver to know that link up =09changed: it might have changed back. =09make the device requirement a weaker "SHOULD" and instead =09ask that driver re-read on each config change notification content.tex | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) diff --git a/content.tex b/content.tex index d68cfaf..f7a6971 100644 --- a/content.tex +++ b/content.tex @@ -2823,6 +2823,7 @@ \subsection{Feature bits}\label{sec:Device Types / Ne= twork Device / Feature bits =20 \item[VIRTIO_NET_F_STANDBY(62)] Device may act as a standby for a primary device with the same MAC address. +\item[VIRTIO_NET_F_SPEED_DUPLEX(63)] Device reports speed and duplex. \end{description} =20 \subsubsection{Feature bit requirements}\label{sec:Device Types / Network = Device / Feature bits / Feature bit requirements} @@ -2882,12 +2883,28 @@ \subsection{Device configuration layout}\label{sec:= Device Types / Network Device VIRTIO_NET_F_MTU is set. This field specifies the maximum MTU for the driv= er to use. =20 +The following two fields, \field{speed} and \field{duplex}, only +exist if VIRTIO_NET_F_SPEED_DUPLEX is set. + +\field{speed} contains the device speed, in units of 1 MBit per +second, 0 to 0x7ffffffff, or 0xfffffffff for unknown speed. + +\field{duplex} has the values of 0x00 for full duplex, 0x01 for +half duplex and 0xff for unknown duplex state. + +Both \field{speed} and \field{duplex} can change, thus the driver +is expected to re-read these values after receiving a +configuration change notification. + \begin{lstlisting} struct virtio_net_config { u8 mac[6]; le16 status; le16 max_virtqueue_pairs; le16 mtu; + le32 speed; + u8 duplex; + }; \end{lstlisting} =20 @@ -2916,6 +2933,19 @@ \subsection{Device configuration layout}\label{sec:D= evice Types / Network Device If the driver negotiates the VIRTIO_NET_F_STANDBY feature, the device MAY = act as a standby device for a primary device with the same MAC address. =20 +If VIRTIO_NET_F_SPEED_DUPLEX has been negotiated, \field{speed} +MUST contain the device speed, in units of 1 MBit per second, 0 to +0x7ffffffff, or 0xfffffffff for unknown. + +If VIRTIO_NET_F_SPEED_DUPLEX has been negotiated, \field{duplex} +MUST have the values of 0x00 for full duplex, 0x01 for half +duplex, or 0xff for unknown. + +If VIRTIO_NET_F_SPEED_DUPLEX and VIRTIO_NET_F_STATUS have both +been negotiated, the device SHOULD NOT change the \field{speed} and +\field{duplex} fields as long as VIRTIO_NET_S_LINK_UP is set in +the \field{status}. + \drivernormative{\subsubsection}{Device configuration layout}{Device Types= / Network Device / Device configuration layout} =20 A driver SHOULD negotiate VIRTIO_NET_F_MAC if the device offers it. @@ -2940,6 +2970,15 @@ \subsection{Device configuration layout}\label{sec:D= evice Types / Network Device =20 A driver SHOULD negotiate the VIRTIO_NET_F_STANDBY feature if the device o= ffers it. =20 +If VIRTIO_NET_F_SPEED_DUPLEX has been negotiated, +the driver MUST treat any value of \field{speed} above +0x7fffffff as well as any value of \field{duplex} not +matching 0x00 or 0x01 as an unknown value. + +If VIRTIO_NET_F_SPEED_DUPLEX has been negotiated, the driver +SHOULD re-read \field{speed} and \field{duplex} after a +configuration change notification. + \subsubsection{Legacy Interface: Device configuration layout}\label{sec:De= vice Types / Network Device / Device configuration layout / Legacy Interfac= e: Device configuration layout} \label{sec:Device Types / Block Device / Feature bits / Device configurati= on layout / Legacy Interface: Device configuration layout} When using the legacy interface, transitional devices and drivers --=20 MST --------------------------------------------------------------------- To unsubscribe from this mail list, you must leave the OASIS TC that=20 generates this mail. Follow this link to all your TCs in OASIS at: https://www.oasis-open.org/apps/org/workgroup/portal/my_workgroups.php=20