Re: [PATCH v2 12/15] arm64: dts: rockchip: Enable dmc and dfi nodes on gru

From: Brian Norris
Date: Wed Apr 06 2022 - 04:27:37 EST


Hello again Peter,

On Fri, Mar 4, 2022 at 6:47 AM Peter Geis <pgwipeout@xxxxxxxxx> wrote:
> Transitions anywhere from the default 800mhz cause a lock.
>
> I'm digging deeper, but I'm hoping you can answer some questions in
> the meantime:
> 1. Does this require something from firmware that isn't available on
> Mainline ATF? (AKA special firmware to the Chromebook line)
> 2. If not, do you have any recommendations off the top of your head?

I may have a better answer for you now. In the intervening time
period, I've discovered a potentially-relevant bug, involving
interactions between the kernel power-domain driver and ATF. See this
series for my current fixes:

https://lore.kernel.org/linux-rockchip/20220406014842.2771799-1-briannorris@xxxxxxxxxxxx/
[RFC PATCH 0/2] rockchip / devfreq: Coordinate DRAM controller
resources between ATF and kernel

If that happens to help you (it may help, for instance, if your system
was toggling NPLL off/on like mine was; it also may help if you're
hitting a race on PMU_BUS_IDLE_REQ like noticed in patch 1), I'd love
your feedback there.

It's still possible your problems are completely unrelated though.

Regards,
Brian