Hi Marek,
On Thu, 16 Oct 2025 at 16:13, Marek Vasut <[email protected]> wrote:
> On 10/16/25 12:14 PM, Geert Uytterhoeven wrote:
> >> which are also never disabled, do we want to disable the GPU by default
> >> and enable per-board ?
> >
> > Yes please. We do the same with renesas,*-mali GPU nodes.
> > The board may not even have graphical output.
> > Or do you envision using the GPU for more general and headless operation?
>
> The GPU does have GP-GPU compute shader, so even headless system can do
> compute on the GPU.
How is this handled on other SoCs?
> >> I would argue the GPU should be enabled by default, so the GPU driver
> >> can do a proper power management of the GPU. If firmware is missing, at
> >> least power it off on failed probe, if nothing else.
> >
> > The *_PD_3DG_* domains are powered down anyway when unused.
>
> If the driver was bound to the GPU node, then the domain would be surely
> powered down in control of the Linux kernel driver, without depending on
> the prior stage to leave it powered down.
>
> I think it is in fact better to bind the GPU driver to the GPU IP and
> let the GPU driver power manage the GPU in a well defined manner,
> instead of depending on the prior stage to leave the GPU in some
> specific state ?
The domains are powered down by the rcar-sysc PM Domain driver,
hence the system does not rely on any prior stage taking care of that.
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
