Re: [PATCHv2 9/9] ARM: dts: omap4: convert to use the new clkctrl clocks for the drivers

[Tero Kristo <t-kristo@ti.com>]

On 28/03/17 03:18, Tony Lindgren wrote:
> * Tero Kristo <t-kristo@ti.com> [170317 02:12]:
>> Convert the drivers to use the new clkctrl clocks.
>>
>> Signed-off-by: Tero Kristo <t-kristo@ti.com>
>> ---
>>  arch/arm/boot/dts/omap4.dtsi | 164 ++++++++++++++++++++++++++++++++++++++-----
>>  1 file changed, 146 insertions(+), 18 deletions(-)
>>
>> diff --git a/arch/arm/boot/dts/omap4.dtsi b/arch/arm/boot/dts/omap4.dtsi
>> index 3ecf616..c39304a 100644
>> --- a/arch/arm/boot/dts/omap4.dtsi
>> +++ b/arch/arm/boot/dts/omap4.dtsi
>> @@ -94,16 +94,22 @@
>>  			compatible = "ti,omap4-mpu";
>>  			ti,hwmods = "mpu";
>>  			sram = <&ocmcram>;
>> +			clocks = <&mpuss_clkctrl OMAP4_MPU_CLKCTRL 0>;
>> +			clock-names = "clkctrl";
>>  		};
>
> Oh one more thing. I don't think we should add the clocks
> here as they are now wrongly allocated to the device within
> the interconnect target module. These clocks really belong
> to each interconnect target module that we don't have in the
> dts yet.
>
> So we're better off adding the clockctrl clocks and then
> changing the dts to use the interconnect target modules
> with the clockctrl clocks.

The problem is, you can't just add the clkctrl clock nodes themselves 
alone, as this introduces the problem that any clocks with no users will 
get disabled => causes a boot time hang when all the device clocks get 
shut down.

If you want to delay the usage of the clocks until you have interconnect 
target modules in place, you need to introduce the clock nodes also at 
that point, similar to what needs to be done now to squash patch #8 or #9.

-Tero