Re: [PATCH 6/8] PM / OPP: Support adjusting OPP voltages at runtime

From: Viresh Kumar
Date: Mon May 20 2019 - 00:49:27 EST


On 16-05-19, 17:08, Andrew-sh.Cheng wrote:
> From: Stephen Boyd <sboyd@xxxxxxxxxxxxxx>
>
> On some SoCs the Adaptive Voltage Scaling (AVS) technique is
> employed to optimize the operating voltage of a device. At a
> given frequency, the hardware monitors dynamic factors and either
> makes a suggestion for how much to adjust a voltage for the
> current frequency, or it automatically adjusts the voltage
> without software intervention. Add an API to the OPP library for
> the former case, so that AVS type devices can update the voltages
> for an OPP when the hardware determines the voltage should
> change. The assumption is that drivers like CPUfreq or devfreq
> will register for the OPP notifiers and adjust the voltage
> according to suggestions that AVS makes.
>
> This patch is devired from [1] submitted by Stephen.
> [1] https://lore.kernel.org/patchwork/patch/599279/
>
> Signed-off-by: Stephen Boyd <sboyd@xxxxxxxxxxxxxx>
> Signed-off-by: Roger Lu <roger.lu@xxxxxxxxxxxx>
> ---
> drivers/opp/core.c | 78 ++++++++++++++++++++++++++++++++++++++++++++++++++
> include/linux/pm_opp.h | 11 +++++++
> 2 files changed, 89 insertions(+)

This is an rcu implementation which got removed long back from OPP core. Please
align this with the latest changes.

--
viresh