Re: [PATCH] PM / devfreq: rk3399_dmc: Fix kernel oops when rockchip,pmu is absent

From: Marc Zyngier
Date: Tue Jun 23 2020 - 06:33:15 EST


On 2020-06-23 09:55, Heiko StÃbner wrote:
Am Montag, 22. Juni 2020, 17:07:52 CEST schrieb Marc Zyngier:

[...]

maz@fine-girl:~$ sudo dtc -I dtb /sys/firmware/fdt 2>/dev/null | grep -A
5 dmc
dmc {
u-boot,dm-pre-reloc;
compatible = "rockchip,rk3399-dmc";
devfreq-events = <0xc8>;

[followed by a ton of timings...]

It is definitely coming from u-boot (I don't provide any DTB otherwise,
and you can find the corresponding node and timings in the u-boot tree).

which is probably the source of the problem :-) .

I'm pretty sure the "reviewed" binding in the kernel doesn't match the
dt-nodes used in uboot.

and the driver doesn't match the binding either. Frankly, this is badly
messed up.

While u-boot these days syncs the main devicetrees from Linux, the memory
setup stuff is pretty specific to uboot (and lives in separate dtsi files).

And I guess you're the only one feeding uboot's dtb to Linux directly, hence
nobody else did encounter this before ;-) .

I'm not "feeding" it directly. I'm using the expected DT distribution
mechanism, which is the boot firmware. Nobody should ever have to provide
their own DT to the kernel.

Thanks,

M. (starting to like ACPI more and more every day)
--
Jazz is not dead. It just smells funny...