Re: [PATCH v2] mailbox: omap-mailbox: Check for pending msgs only when mbox is exclusive

From: Francesco Dolcini

Date: Wed Nov 26 2025 - 04:51:28 EST


Hello Jassi,

On Tue, Nov 04, 2025 at 01:41:11AM +0530, Beleswar Padhi wrote:
> On TI K3 devices, the mailbox resides in the Always-On power domain
> (LPSC_main_alwayson) and is shared among multiple processors. The
> mailbox is not solely exclusive to Linux.
>
> Currently, the suspend path checks all FIFO queues for pending messages
> and blocks suspend if any are present. This behavior is unnecessary for
> K3 devices, since some of the FIFOs are used for RTOS<->RTOS
> communication and are independent of Linux.
>
> For FIFOs used in Linux<->RTOS communication, any pending message would
> trigger an interrupt, which naturally prevents suspend from completing.
> Hence, there is no need for the mailbox driver to explicitly check for
> pending messages on K3 platforms.
>
> Introduce a device match flag to indicate whether the mailbox instance
> is exclusive to Linux, and skip the pending message check for
> non-exclusive instances (such as in K3).
>
> Fixes: a49f991e740f ("arm64: dts: ti: k3-am62-verdin: Add missing cfg for TI IPC Firmware")
> Closes: https://lore.kernel.org/all/sid7gtg5vay5qgicsl6smnzwg5mnneoa35cempt5ddwjvedaio@hzsgcx6oo74l/
> Signed-off-by: Beleswar Padhi <b-padhi@xxxxxx>

What's the status of this? It's fixing a real issue, and it has been
tested and reviewed. Any blocker to merge it?

Thanks
Francesco