[PATCH 1/1] ARM: dts: Use more descriptive names for Exynos5420 PDs
Sergei Shtylyov
sergei.shtylyov at cogentembedded.com
Tue Feb 10 03:55:16 PST 2015
Hello.
On 2/10/2015 2:46 PM, Krzysztof Kozlowski wrote:
>>>> All the device nodes for the Exynos5420 power-domains have a quite
>>>> generic "power-domain" name.
>>> And this is in conformance to the ePAPR standard.
>> True, I forgot that the ePAPR recommends that the node names should be
>> somewhat generic but OTOH this is the only Exynos DTSI file that follows
>> the standard for the power domain device nodes. All other Exynos DTSI
>> use a prefix to differentiate between each power domain.
>>>> So in case of an error, the Exynos PD
>>>> driver shows the following (not very useful) message:
>>>> "Power domain power-domain disable failed"
>>> Why not fix the message instead to use the full device name?
>> Well, the full node name is also not very useful IMHO since you have
>> to check the DTSI or SoC manual to map the device node unit-address to
>> the corresponding power domain.
>> I used $subject when debugging an HDMI issue and instead of dropping
>> it, I just posted it in case someone considered useful. I don't really
>> mind if the patch is nacked / not picked.
> Additionally (on Arndale Octa):
> $ cat /sys/kernel/debug/pm_genpd/pm_genpd_summary
> domain status slaves
> /device runtime status
> ----------------------------------------------------------------------
> power-domain on
> /devices/platform/amba/3880000.adma suspended
> power-domain off
> power-domain off
> power-domain off
> power-domain off
> power-domain off
> This really is not helpful. From the power domain debugfs code it is
> complicated to extract of_node of power domain.
You shouldn't need it.
> It is easier to print
> the name of power domain. But wait... all names are the same! :) So
> why do we have the name in the first place?
I'm not sure why the full platform device names aren't printed -- they
should all be different.
WBR, Sergei
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