[REGRESSION] Suspend to RAM does not work anymore with k3-am62-ti-ipc-firmware.dtsi

[Beleswar Prasad Padhi]

On 21/10/25 14:33, Beleswar Prasad Padhi wrote:
> Hi Hiago,
>
> On 20/10/25 19:47, Hiago De Franco wrote:
>> Hello all,
>>
>> After commit 1d6161617c10 (“arm64: dts: ti: k3-am62-ti-ipc-firmware:
>> Refactor IPC cfg into new dtsi”), suspend-to-RAM stopped working on
>> AM62x.
>
> The above commit is only refactoring changes and should not
> cause any trouble. I think the commit you are interested in
> should be: a49f991e740f ("arm64: dts: ti: k3-am62-verdin:
> Add missing cfg for TI IPC Firmware").
>

<snip>

>
>> Do you have suggestions on how best to fix this in the driver, or should
>> we consider reverting the DTS change until suspend-to-RAM works again?
>
> List of suggestions/solutions in order of preference:
> 1. If no intention to enable IPC on rprocs:
>       Do _not_ include k3-am62-ti-ipc-firmware.dtsi
> 2. If intention is to enable IPC on rprocs:
>       Make sure rproc firmware is available in rootfs.
>       rproc would boot up and consume the mbox
>       msg, suspend would be successful. Tested this
>       on TI AM62x-sk with commit 1d6161617c, works
> 3. Add support in mbox driver to flush the pending
>     queues.


Posted a RFC version for #3:
https://lore.kernel.org/all/20251022102015.1345696-1-b-padhi@ti.com/

It still has open questions regarding scenarios with
FIFO firewalling and supporting existing OMAP SoCs
which could restore context upon resume.

Cc: Andrew, Hari

Thanks,
Beleswar