[PATCH 2/2] cpufreq: cpu0: Extend support beyond CPU0

Shawn Guo shawn.guo at linaro.org
Sat Jun 28 07:52:54 PDT 2014


On Wed, Jun 25, 2014 at 02:12:29PM +0530, Viresh Kumar wrote:
> cpufreq-cpu0 driver supports only platforms which have single clock line shared
> among all CPUs.
> 
> We already have platforms where this limitation doesn't hold true.For example on
> Qualcomm's KRAIT all CPUs have separate clock line and so have separate
> policies.
> 
> Instead of adding another driver for this (Stephen just tried that:
> https://lkml.org/lkml/2014/6/24/918), we must reuse cpufreq-cpu0 driver.
> 
> cpufreq-cpu0 must be updated to break the assumption on which it is based (all
> cores sharing clock line) and this patch tries to do exactly that.
> 
> As we don't have standard DT bindings to mention CPUs sharing clock-line, i.e.
> affected_cpus, this patch also have few limitations. Though easy to fix once we
> have proper bindings.
> 
> Limitation: We only supports two types of platforms:
> - All CPUs sharing same clock line, existing user platforms
> - All CPUs have separate clock lines, KRAIT
> 
> And so platforms which have multiple clusters with multiple CPUs per cluster
> aren't supported yet. We need proper bindings for that first.
> 
> Signed-off-by: Viresh Kumar <viresh.kumar at linaro.org>
> ---
>  .../devicetree/bindings/cpufreq/cpufreq-cpu0.txt   |   8 +-
>  drivers/cpufreq/Kconfig                            |   5 +-
>  drivers/cpufreq/cpufreq-cpu0.c                     | 280 +++++++++++++--------
>  3 files changed, 190 insertions(+), 103 deletions(-)

Hi Viresh,

Thanks for all the effort on maintaining and improving cpufreq-cpu0
driver.  Your patch rewrote the most part of the driver, so I'd like to
hand over the driver to you.  Please add yourself as the primary person
for MODULE_AUTHOR.

Shawn



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