Re: [PATCH V6 0/7] cpufreq: suspend early/resume late: dpm_{suspend|resume}()

Stephen Warren
2014-02-18T20:30:58Z

On 02/17/2014 02:25 AM, Viresh Kumar wrote:
> This patchset creates/calls cpufreq suspend/resume callbacks from dpm_{suspend|resume}()
> for handling suspend/resume of cpufreq governors and core.
>
> There are multiple problems that are fixed by this patch:
> - Nishanth Menon (TI) found an interesting problem on his platform, OMAP. His board
> wasn't working well with suspend/resume as calls for removing non-boot CPUs
> was turning out into a call to drivers ->target() which then tries to play
> with regulators. But regulators and their I2C bus were already suspended and
> this resulted in a failure. Many platforms have such problems, samsung, tegra,
> etc.. They solved it with driver specific PM notifiers where they used to
> disable their driver's ->target() routine.
> - Lan Tianyu (Intel) & Jinhyuk Choi (Broadcom) found an issue where tunables
> configuration for clusters/sockets with non-boot CPUs was getting lost after
> suspend/resume, as we were notifying governors with CPUFREQ_GOV_POLICY_EXIT on
> removal of the last cpu for that policy and so deallocating memory for
> tunables. This is fixed by this patch as we don't allow any operation on
> governors after device suspend and before device resume now.

The series,
Tested-by: Stephen Warren <swarren@nvidia.com>

Patch 7/7,
Acked-by: Stephen Warren <swarren@nvidia.com>