Re: [PATCH v4 0/3] Introduce support for T-head TH1520 Mailbox

[Drew Fustini <dfustini@tenstorrent.com>]

On Mon, Oct 14, 2024 at 02:33:11PM +0200, Michal Wilczynski wrote:
> The T-head TH1520 SoC supports a hardware mailbox that enables two cores
> within the SoC to communicate and coordinate [1]. One example of such
> coordination would be cooperation with the T-Head E902 core, which is
> responsible for power, clock, and resource management. For example, in
> the specific case of the BXM-4-64 GPU, it needs to be powered on by the
> E902 core, and the kernel running on the E910 needs to 'ask' the
> firmware running on the E902 core to enable power to the GPU island.
> Given recent advancements in work on the upstream GPU driver [2], there
> is an emerging need to get this code in the mainline kernel.
> 
> Link: https://openbeagle.org/beaglev-ahead/beaglev-ahead/-/blob/main/docs/TH1520%20System%20User%20Manual.pdf [1]
> Link: https://gitlab.freedesktop.org/imagination/linux-firmware/-/issues/1 [2]
> 
> Thanks, Krzysztof and Rob, for your review! Since this series is gaining
> some interest, I've dropped the RFC prefix with the v3 update.

I've applied this series and booted okay. I see the driver loaded:

 /sys/devices/platform/soc/ffffc38000.mailbox/driver points to
 /sys/bus/platform/drivers/th1520-mbox

How do you test that the communication with the E902 is working
correctly?

Thanks,
Drew