Hello Quentin,
On 2024-11-06 10:32, Quentin Schulz wrote:
On 11/6/24 9:33 AM, Dragan Simic wrote:
Add support for voltage ranges to the CPU, GPU and DMC OPPs defined in
the
SoC dtsi for Rockchip OP1, as a variant of the Rockchip RK3399. This
may be
useful if there are any OP1-based boards whose associated voltage
regulators
are unable to deliver the exact voltages; otherwise, it causes no
functional
changes to the resulting OPP voltages at runtime.
These changes cannot cause stability issues or any kind of damage,
because
it's perfectly safe to use the highest voltage from an OPP group for
each OPP
in the same group. The only possible negative effect of using higher
voltages
is wasted energy in form of some additionally generated heat.
Reported-by: Quentin Schulz <quentin.schulz@xxxxxxxxx>
Well, I merely highlighted that the voltage was different on OP1
compared to RK3399 for the 600MHz OPP :)
I just wanted to somehow acknowledge that you made me work on
this patch, so to speak. :)
So... If there's ONE SoC I'm pretty sure is working as expected it's
the OP1 fitted on the Gru Chromebooks with the ChromiumOS kernel fork
(though yes, I believe all Gru CB are EoL since August 2023). In the
6.1 kernel fork, there's also no range:
https://chromium.googlesource.com/chromiumos/third_party/kernel/+/refs/heads/chromeos-6.1/arch/arm64/boot/dts/rockchip/rk3399-op1-opp.dtsi
So not sure we need to handle theoretical cases here. Will let
maintainers decide on that one. FWIW, there are two other OP1 devices,
the RockPi4A+ and RockPi4B+ which do not change the OPP either.
The thing is that adding the voltage ranges won't change anything
for the devices whose voltage regulators are capable of providing
the exact OPP voltages. They'll still be set to the exact values
as before these changes, so there's no worry about breaking anything,
while we make the things a bit more consistent this way.
I also plan to implement and upstream the DT for TinkerBoard 2S,
which is based on the OP1, and its voltage regulator setup may
actually need these voltage ranges.
