[PATCH V2 1/4] cpufreq: add arm soc generic cpufreq driver
Richard Zhao
richard.zhao at linaro.org
Sat Dec 17 03:39:54 EST 2011
On Fri, Dec 16, 2011 at 11:59:02AM -0800, Bryan Huntsman wrote:
> On 12/16/2011 02:52 AM, Jamie Iles wrote:
> >
> >> +static DEFINE_PER_CPU(unsigned long, l_p_j_ref);
> >> +static unsigned long l_p_j_ref_freq;
> >> +
> >> +static struct clk *cpu_clk;
> >
> > This assumes that all CPU's share the same clk and run at the same rate.
> > Is that a fair/safe assumption? I honestly don't know the answer to
> > this so it's just a question!!!
>
> On MSM, cpus independently scale both frequency and voltage. Our clock
> driver isn't upstream yet. David Brown has a preliminary version here:
If
- cpu_clk are per_cpu, and get from cpu0 clk, cpu1 clk, etc.
The same to regulators.
- set CPUFREQ_SHARED_TYPE_NONE
- don't set affect cpus.
Does that help you?
Thanks
Richard
>
> https://www.codeaurora.org/gitweb/quic/kernel/?p=davidb/linux-msm.git;a=shortlog;h=refs/heads/msm-clock-rfc
>
> Once we get our driver upstream, MSM will be an exception and not select
> ARM_GENERIC_CPUFREQ. We'll probably have a separate msm-cpufreq.c
> driver under drivers/cpufreq/.
>
> - Bryan
>
> --
> Sent by an employee of the Qualcomm Innovation Center, Inc.
> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.
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