[PATCH 3/3] imx: power-domain: Get rid of SMCCC dependency

[Marek Vasut]

On 4/17/22 20:24, Adam Ford wrote:

Hi,

>>> When I just reverted all three of those, it still hangs.  However,
>>> when I removed CONFIG_CLK, it recovered.  I'll examine which clocks
>>> may be missing or if there is some other clock dependency.
>>
>> Hum, clock sounds indeed more plausible cause of the hang because the
>> SMC calls (or the power domain driver) does not come up so early in the
>> process. (the other possibility is that you're running of MALLOC_F space
>> due to the extra clock).
>>
>> The obvious other question I have would be -- does it hang if you only
>> enable CONFIG_CLK=y without these patches here ?
> 
> It appears that I just needed to enable the CCF, CCF composite, and
> the IMX8MQ clock driver which were previously disabled by default.
> With those enabled, it booted just fine.
> Once it booted, I was able to start the USB system and it detected a
> USB thumb drive.
> 
> I did not enable them in SPL, but I can try it if you want.

Oh, right, now you actually can bring up USB in SPL, that's a nice bonus.

> Should we expand the power domain dependency to include these clocks,
> or should these clocks just turn on by default if/when the 8MQ is the
> target SOC?

Probably add something like this into the Kconfig file:

select CLK_IMX8MQ if IMX8MQ

for all four MX8M variants and for all SPL variants (so 8 entries total) 
and that should fix the clock dependency in general.

> At this point, I don't think it's a MALLOC_F issue, but I considered that.
> 
> I can mark your patch with a t-b, but I am not sure if you want to do
> a V2 with these clocks enabled or do something different.

Maybe just send a subsequent patch. That's likely easier on Stefano, 
since this series is already buries deep in his master-next branch.