Re: [PATCH V5 5/5] of: unittest: Statically apply overlays using fdtoverlay

From: Frank Rowand
Date: Thu Jan 21 2021 - 00:56:00 EST


On 1/20/21 11:43 PM, Viresh Kumar wrote:
> Hi Frank,
>
> On 20-01-21, 23:34, Frank Rowand wrote:
>> It should be possible to apply this same concept to copying overlay_base.dts
>> to overlay_base_base.dts, removing the "/plugin/;" from overlay_base_base.dts
>> and using an additional rule to use fdtoverlay to apply overlay.dtb on top
>> of overlay_base_base.dtb.
>
> Are you suggesting to then merge this with testcases.dtb to get
> static_test.dtb

no

> or keep two output files (static_test.dtb from
> testcases.dtb + overlays and static_test2.dtb from overlay_base.dtb
> and overlay.dtb) ?

yes, but using the modified versions ("/plugin/;" removed) of
testcases.dtb and overlay_base.dtb.

>
> Asking because as I mentioned earlier, overlay_base.dtb doesn't have
> __overlay__ property for its nodes and we can't apply that to
> testcases.dtb using fdtoverlay.

Correct.

I apologize in advance if I get confused in these threads or cause confusion.
I find myself going in circles and losing track of how things fit together as
I move through the various pieces of unittest.

-Frank

>
>> Yes, overlay_base_base is a terrible name. Just used to illustrate the point.
>>
>> I tried this by hand and am failing miserably. But I am not using the proper
>> environment (just a quick hack to see if the method might work). So I would
>> have to set things up properly to really test this.
>>
>> If this does work, it would remove my objections to you trying to transform
>> the existing unittest .dts test data files (because you would not have to
>> actually modify the existing .dts files).
>