RE: [PATCH 3/3] cpufreq: imx-sc: add i.mx system controller cpufreq support

[Anson Huang]

Best Regards!
Anson Huang

> -----Original Message-----
> From: Viresh Kumar [mailto:viresh.kumar@xxxxxxxxxx]
> Sent: 2019年2月13日 18:15
> To: Anson Huang <anson.huang@xxxxxxx>
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> Subject: Re: [PATCH 3/3] cpufreq: imx-sc: add i.mx system controller cpufreq
> support
> 
> On 13-02-19, 08:53, Anson Huang wrote:
> > Forgot to mention, i.MX system controller cpufreq actually can NOT do
> > any CPU clock/voltage scaling from Linux kernel, they are controlled
> > by system controller firmware and ONLY can be requested via RPC with
> > secure mode, so Linux kernel has to call SMC and trap to
> > ARM-Trusted-Firmware to do it, in this case, is cpufreq-dt still
> > suitable to support it? I saw cpufreq-dt driver will do CPU clock/voltage
> scaling directly.
> 
> What about moving those SMC calls to the clk-driver, then it wouldn't matter
> to the cpufreq driver on how the clock is getting changed.

OK, thanks, I will have a try and resend the patch.

Anson.

> 
> --
> viresh