[PATCH v2 2/2] cpufreq: ti: Add cpufreq driver to determine available OPPs at runtime

Viresh Kumar viresh.kumar at linaro.org
Thu Sep 22 22:19:47 PDT 2016


On 21-09-16, 14:34, Dave Gerlach wrote:
> Viresh,
> On 09/07/2016 10:39 PM, Viresh Kumar wrote:
> >On 07-09-16, 10:04, Dave Gerlach wrote:
> >>>>+static const struct of_device_id ti_cpufreq_of_match[] = {
> >>>>+	{ .compatible = "operating-points-v2-ti-am3352-cpu",
> >>>>+	  .data = &am3x_soc_data, },
> >>>>+	{ .compatible = "operating-points-v2-ti-am4372-cpu",
> >>>>+	  .data = &am4x_soc_data, },
> >>>>+	{ .compatible = "operating-points-v2-ti-dra7-cpu",
> >>>>+	  .data = &dra7_soc_data },
> >>>
> >>>You should be using your SoC compatible strings here. OPP compatible
> >>>property isn't supposed to be (mis)used for this purpose.
> >>>
> >>
> >>Referring to my comments in patch 1, what if we end up changing the bindings
> >>based on DT maintainer comments? We will have these compatible strings, and
> >>at that point is it acceptable to match against them? Or is it still better
> >>to match to SoC compatibles? I think it makes sense to just probe against
> >>these.
> >
> >But even then I think these are not correct. You should have added a
> >single compatible string: operating-points-v2-ti-cpu.
> >
> >As the properties will stay the same across machines. And then you
> >need to use SoC strings here.
> >
> 
> Are you opposed to moving _of_get_opp_desc_node from
> drivers/base/power/opp/opp.h to include/linux/pm_opp.h and renaming it
> appropriately?

I am not opposed to that, but ...

> If I move the ti properties out of the cpu node, as discussed in patch 1 of
> this series, and into the operating-points-v2 table, I need a way to get the
> operating-points-v2 device node and I think it makes sense to reuse this as
> it is what the opp framework uses internally to parse the phandle to the opp
> table.

I am not sure if those registers belong to the OPP bindings. What are those
registers really? What all can be read from them? Why shouldn't they be present
as a separate node in DT on the respective bus? Look at how it is done for
sti-cpufreq driver.

-- 
viresh



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