From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Max Gurtovoy Subject: [PATCH v5 5/7] Add miscellaneous configuration structure for PCI Date: Wed, 27 Apr 2022 01:58:22 +0300 Message-ID: <20220426225824.5918-6-mgurtovoy@nvidia.com> In-Reply-To: <20220426225824.5918-1-mgurtovoy@nvidia.com> References: <20220426225824.5918-1-mgurtovoy@nvidia.com> MIME-Version: 1.0 Content-Type: text/plain To: jasowang@redhat.com, virtio-comment@lists.oasis-open.org, mst@redhat.com, cohuck@redhat.com, virtio-dev@lists.oasis-open.org Cc: oren@nvidia.com, parav@nvidia.com, shahafs@nvidia.com, aadam@redhat.com, virtio@lists.oasis-open.org, Max Gurtovoy List-ID: This new structure will be used for adding new miscellaneous registers for a virtio device configuration layout. For now, only admin_queue_index register is added. Admin virtqueue index does not depend on the device type. Hence, add a PCI capability to read the admin virtqueue index. Reviewed-by: Parav Pandit Signed-off-by: Max Gurtovoy --- conformance.tex | 2 ++ content.tex | 29 +++++++++++++++++++++++++++++ 2 files changed, 31 insertions(+) diff --git a/conformance.tex b/conformance.tex index 3c7b7bc..c183581 100644 --- a/conformance.tex +++ b/conformance.tex @@ -103,6 +103,7 @@ \section{Conformance Targets}\label{sec:Conformance / Conformance Targets} \item \ref{drivernormative:Virtio Transport Options / Virtio Over PCI Bus / PCI Device Layout / PCI configuration access capability} \item \ref{drivernormative:Virtio Transport Options / Virtio Over PCI Bus / PCI-specific Initialization And Device Operation / Device Initialization / MSI-X Vector Configuration} \item \ref{drivernormative:Virtio Transport Options / Virtio Over PCI Bus / PCI-specific Initialization And Device Operation / Notification of Device Configuration Changes} +\item \ref{drivernormative:Virtio Transport Options / Virtio Over PCI Bus / PCI Device Layout / Miscellaneous configuration structure layout} \end{itemize} \conformance{\subsection}{MMIO Driver Conformance}\label{sec:Conformance / Driver Conformance / MMIO Driver Conformance} @@ -364,6 +365,7 @@ \section{Conformance Targets}\label{sec:Conformance / Conformance Targets} \item \ref{devicenormative:Virtio Transport Options / Virtio Over PCI Bus / PCI-specific Initialization And Device Operation / Device Initialization / MSI-X Vector Configuration} \item \ref{devicenormative:Virtio Transport Options / Virtio Over PCI Bus / PCI-specific Initialization And Device Operation / Used Buffer Notifications} \item \ref{devicenormative:Virtio Transport Options / Virtio Over PCI Bus / PCI-specific Initialization And Device Operation / Notification of Device Configuration Changes} +\item \ref{devicenormative:Virtio Transport Options / Virtio Over PCI Bus / PCI Device Layout / Miscellaneous configuration structure layout} \end{itemize} \conformance{\subsection}{MMIO Device Conformance}\label{sec:Conformance / Device Conformance / MMIO Device Conformance} diff --git a/content.tex b/content.tex index 163cb34..0c1d44f 100644 --- a/content.tex +++ b/content.tex @@ -712,6 +712,7 @@ \subsection{Virtio Structure PCI Capabilities}\label{sec:Virtio Transport Option \item ISR Status \item Device-specific configuration (optional) \item PCI configuration access +\item Miscellaneous configuration \end{itemize} Each structure can be mapped by a Base Address register (BAR) belonging to @@ -771,6 +772,8 @@ \subsection{Virtio Structure PCI Capabilities}\label{sec:Virtio Transport Option #define VIRTIO_PCI_CAP_SHARED_MEMORY_CFG 8 /* Vendor-specific data */ #define VIRTIO_PCI_CAP_VENDOR_CFG 9 +/* Miscellaneous configuration */ +#define VIRTIO_PCI_CAP_MISC_CFG 10 \end{lstlisting} Any other value is reserved for future use. @@ -1352,6 +1355,32 @@ \subsubsection{PCI configuration access capability}\label{sec:Virtio Transport O specified by some other Virtio Structure PCI Capability of type other than \field{VIRTIO_PCI_CAP_PCI_CFG}. +\subsubsection{Miscellaneous configuration structure layout}\label{sec:Virtio Transport Options / Virtio Over PCI Bus / PCI Device Layout / Miscellaneous configuration structure layout} + +The miscellaneous configuration structure is found at the bar and offset within the VIRTIO_PCI_CAP_MISC_CFG capability. +Its layout is below. +\begin{lstlisting} +struct virtio_pci_misc_cfg { + le16 admin_queue_index; /* read-only for driver */ +}; +\end{lstlisting} + +\begin{description} +\item[\field{admin_queue_index}] + The device uses this to report the index of the admin virtqueue. + This field is valid only if VIRTIO_F_ADMIN_VQ is set. +\end{description} + +\devicenormative{\paragraph}{Miscellaneous configuration structure layout}{Virtio Transport Options / Virtio Over PCI Bus / PCI Device Layout / Miscellaneous configuration structure layout} +The device MUST present VIRTIO_PCI_CAP_MISC_CFG capability when VIRTIO_F_ADMIN_VQ is set. + +The device MUST present a valid \field{admin_queue_index} when VIRTIO_F_ADMIN_VQ is set. + +\drivernormative{\paragraph}{Miscellaneous configuration structure layout}{Virtio Transport Options / Virtio Over PCI Bus / PCI Device Layout / Miscellaneous configuration structure layout} +The driver MUST NOT proceed with configuring the admin virtqueue in case VIRTIO_F_ADMIN_VQ is set and VIRTIO_PCI_CAP_MISC_CFG capability is not present. + +The driver MUST use the value of \field{admin_queue_index} to configure the admin virtqueue. For more details on virtqueue configuration see section \ref{sec:Virtio Transport Options / Virtio Over PCI Bus / PCI-specific Initialization And Device Operation / Device Initialization / Virtqueue Configuration}. + \subsubsection{Legacy Interfaces: A Note on PCI Device Layout}\label{sec:Virtio Transport Options / Virtio Over PCI Bus / PCI Device Layout / Legacy Interfaces: A Note on PCI Device Layout} Transitional devices MUST present part of configuration -- 2.21.0