[PATCH] cpufreq: rockchip: add driver
Feng Xiao
xf at rock-chips.com
Mon Mar 21 18:28:00 PDT 2016
I get it, thanks.
在 2016/3/21 23:52, Heiko Stübner 写道:
> Am Montag, 21. März 2016, 16:13:40 schrieb Heiko Stübner:
>> Hi,
>>
>> Am Montag, 21. März 2016, 21:24:32 schrieb Feng Xiao:
>>> 在 2016/3/21 17:58, Viresh Kumar 写道:
>>>> On 21-03-16, 10:54, Heiko Stübner wrote:
>>>>> I hadn't seen that yet ... nice that cpufreq-dt now also supports
>>>>> clusters :-)
>>>>>
>>>>> The other part still stands though, as we probably should register the
>>>>> platform-device somewhere else and not in some new special module.
>>>>>
>>>>> When everything is using cpufreq-dt now, I guess we could just add it
>>>>> to
>>>>> the core rockchip clk-code. Or was there some agreement where this
>>>>> should be done (obviously not the devicetree itself)?
>>> Of_clk_init is called early, and platform_device_register_simple should
>>> be called after devices_init, it will be failed to do it from clk-code.
>>> So we need add a new file or add module_init to each clock controller
>>> driver(like clk-rk3368.c, clk-rk3399.c) ?
>> as Viresh said, it should be ok to do it like your approach creating a
>> module in drivers/cpufreq. But the compatible check is necessary.
>>
>> Doing it this way also makes it easier to have
> Seem like I forgot the complete my sentence here. This should've been
>
> Doing it this way also makes it easier to have everything go into cpufreq-dt
> once that whitelist appears that Viresh wrote about. So this might be better
> than to distribute this stuff around other subsystems, as I originally
> suggested.
>
>>>> Yeah, there was a discussion around creating a white or black list of
>>>> platforms that want to create a platform device for cpufreq-dt. That can
>>>> be done in cpufreq-dt.c or a new file, but I haven't worked out on that
>>>> yet.
>>>>
>>>> You can do it from clk-code or from the driver that was added in this
>>>> thread. Just that you need to match your platform's compatible string
>>>> before doing that.
>>> Rockchip-cpufreq.c depends on ARM_ROCKCHIP_CPUFREQ, it will not be
>>> compiled on non-Rockchip platforms.
>>> The driver can support all Rockchip SoCs up to now, add
>>> of_machine_is_compatible may be redundant ?
>> Please always keep multiplatform in mind. These days the kernel can be
>> compiled for multiple architectures at the same time, so you can have
>> support for Rockchip, Exynos, Qualcom and whatever in the same kernel
>> image.
>>
>> Therefore a compile-time check is not enough and you need to check the
>> actually running machine as well.
>>
>>
>> Heiko
>
>
>
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