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Date:   Wed, 13 Feb 2019 12:39:04 +0530
From:   Viresh Kumar <viresh.kumar@linaro.org>
To:     Anson Huang <anson.huang@nxp.com>
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Subject: Re: [PATCH 3/3] cpufreq: imx-sc: add i.mx system controller cpufreq
 support
Message-ID: <20190213070904.3oswrjafy6cqedsr@vireshk-i7>
References: <1550027011-7884-1-git-send-email-Anson.Huang@nxp.com>
 <1550027011-7884-3-git-send-email-Anson.Huang@nxp.com>
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On 13-02-19, 03:09, Anson Huang wrote:
> On NXP's i.MX SoCs with system controller inside, CPU frequency
> scaling can ONLY be done by system controller firmware, and it
> can ONLY be requested from secure mode, so Linux cpufreq driver has
> to call ARM SMC to trap to ARM-Trusted-Firmware to request system
> controller firmware to do CPU frequency scaling.
> 
> This patch adds i.MX system controller cpufreq driver support,
> when doing CPU frequency scaling, cpufreq driver will do ARM SMC
> call and trap to ARM-Trusted-Firmware, then SIP(silicon provider)
> service will communicate with system controller for CPU frequenct
> scaling.
> 
> Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
> ---
>  drivers/cpufreq/Kconfig.arm      |   9 ++
>  drivers/cpufreq/Makefile         |   1 +
>  drivers/cpufreq/imx-sc-cpufreq.c | 183 +++++++++++++++++++++++++++++++++++++++
>  3 files changed, 193 insertions(+)
>  create mode 100644 drivers/cpufreq/imx-sc-cpufreq.c

Why can't you use cpufreq-dt driver like everyone else ?

-- 
viresh