Gunyah message queues are a unidirectional inter-VM pipe for messages up
to 1024 bytes. This driver supports pairing a receiver message queue and
a transmitter message queue to expose a single mailbox channel.
Signed-off-by: Elliot Berman <quic_eberman@xxxxxxxxxxx>
---
Documentation/virt/gunyah/message-queue.rst | 8 +
drivers/mailbox/Makefile | 2 +
drivers/mailbox/gunyah-msgq.c | 212 ++++++++++++++++++++
include/linux/gunyah.h | 57 ++++++
4 files changed, 279 insertions(+)
create mode 100644 drivers/mailbox/gunyah-msgq.c
diff --git a/Documentation/virt/gunyah/message-queue.rst b/Documentation/virt/gunyah/message-queue.rst
index b352918ae54b..70d82a4ef32d 100644
--- a/Documentation/virt/gunyah/message-queue.rst
+++ b/Documentation/virt/gunyah/message-queue.rst
@@ -61,3 +61,11 @@ vIRQ: two TX message queues will have two vIRQs (and two capability IDs).With best wishes
| | | | | |
| | | | | |
+---------------+ +-----------------+ +---------------+
+
+Gunyah message queues are exposed as mailboxes. To create the mailbox, create
+a mbox_client and call `gh_msgq_init()`. On receipt of the RX_READY interrupt,
+all messages in the RX message queue are read and pushed via the `rx_callback`
+of the registered mbox_client.
+
+.. kernel-doc:: drivers/mailbox/gunyah-msgq.c
+ :identifiers: gh_msgq_init--