On Fri, Mar 31, 2023 at 01:58:33AM +0300, Parav Pandit wrote: > PCI devices support memory BAR regions for performant driver > notifications using the notification capability. > Enable transitional MMR devices to use it in simpler manner. > > Co-developed-by: Satananda Burla <[email protected]> > Signed-off-by: Parav Pandit <[email protected]> > --- > transport-pci.tex | 28 ++++++++++++++++++++++++++++ > 1 file changed, 28 insertions(+) > > diff --git a/transport-pci.tex b/transport-pci.tex > index 55a6aa0..4fd9898 100644 > --- a/transport-pci.tex > +++ b/transport-pci.tex > @@ -763,6 +763,34 @@ \subsubsection{Notification structure > layout}\label{sec:Virtio Transport Options > cap.length >= queue_notify_off * notify_off_multiplier + 4 > \end{lstlisting} > > +\paragraph{Transitional MMR Interface: A note on Notification Capability} > +\label{sec:Virtio Transport Options / Virtio Over PCI Bus / Virtio Structure > PCI Capabilities / Notification capability / Transitional MMR Interface} > + > +The transitional MMR device benefits from receiving driver > +notifications at the Queue Notification address offered using > +the notification capability, rather than via the memory mapped > +legacy QueueNotify configuration register. > + > +Transitional MMR device uses same Queue Notification address > +within a BAR for all virtqueues: > +\begin{lstlisting} > +cap.offset > +\end{lstlisting} > + > +The transitional MMR device MUST support Queue Notification > +address within a BAR for all virtqueues at: > +\begin{lstlisting} > +cap.offset > +\end{lstlisting} > + > +The transitional MMR driver that wants to use driver > +notifications offered using notification capability MUST use > +same Queue Notification address within a BAR for all virtqueues at: > + > +\begin{lstlisting} > +cap.offset > +\end{lstlisting} > + > \subsubsection{ISR status capability}\label{sec:Virtio Transport Options / > Virtio Over PCI Bus / PCI Device Layout / ISR status capability} > > The VIRTIO_PCI_CAP_ISR_CFG capability
Why? What exactly is going on here? legacy drivers will not do this. > -- > 2.26.2 --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
