Re: [PATCH v2 1/1] drm/tyr: make SRAM supply optional like panthor

[Boris Brezillon]

On Thu, 12 Feb 2026 15:16:44 +0300
Onur Özkan <work@xxxxxxxxxxxxx> wrote:

> On Thu, 12 Feb 2026 11:34:41 +0000
> Mark Brown <broonie@xxxxxxxxxx> wrote:
> 
> > On Thu, Feb 12, 2026 at 01:05:38PM +0300, Onur Özkan wrote:  
> > > On rk3588s, `dmesg | grep 'tyr'` logs:
> > > 
> > >   tyr fb000000.gpu: supply SRAM not found, using dummy regulator
> > > 
> > > This happens because Tyr calls Regulator<Enabled>::get() for SRAM,
> > > which goes through the non-optional regulator_get() path. If the
> > > device tree doesn't provide sram-supply, regulator core falls back
> > > to a dummy regulator and writes that log.  
> >   
> > > Panthor handles SRAM as optional and tolerates missing sram-supply.  
> > 
> > Does the RAM really work without power?  
> 
> If the platform has no separate sram-supply (meaning that rail is
> coupled to mali), RAM should still be powered and work fine. Panthor
> already relies on this model by treating sram-supply as optional and
> as far as I can see there are no RAM issues on Panthor.

Yep, some SoC integration have just one power-rail for everything in
the GPU, others have two. The sram-supply is documented as optional in
the DT bindings, so I think that's the right thing to do.

Reviewed-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxx>

> 
> - Onur