PROCESSOR-SDK-J721E: Example OMAP Mailbox client driver usage

Hi Kamel,

In the Linux repository: drivers/mailbox/omap-mailbox.c

The above is the driver for the hardware mailboxes on J7.

- Keerthy

Hi Kamel,

I am not sure what you are looking for or trying to do.

The above OMAP Mailbox driver is the TI Platform Mailbox Controller driver, that plugs into the Mailbox subsystem. The client users will use the generic Mailbox API.

The only client user for Mailboxes in Linux kernel are the corresponding TI remoteproc drivers and used to provide the virtio-rpmsg IPC transport.

regards

Suman

Hi Kamel,

Both the HwSpinlock and Mailbox IPs typically require you to run a firmware on a different processor, to really test the MultiCore Locks, or the IPC between Linux and another processor using Mailboxes.

The above referenced HwSpinLock test is a Unit-Test on the Linux side that performs API testing of acquiring and releasing locks from the Linux-side.

The standard Linux has a generic Mailbox test driver/code in drivers/mailbox/mailbox-test.c that requests two mailbox channels one for Rx and Tx, and presents a character device interface to userspace. You can try to adapt this to work with the OMAP Mailboxes.

I also managed to find a really old Linux-only loop-back test code during my Mailbox upstreaming days on a very old kernel. You can leverage that as well.

Please see the driver test code and dts node usage references in the following branch,

https://github.com/sumananna/mailbox/commits/mbox/test/5.3-rc1-k3

Here's the direct test driver code reference,

https://github.com/sumananna/mailbox/commit/d40f008bbbd5a999762971b5792049689da19cf7

regards

Suman