Re: [PATCH 2/2] ARM: dts: mvebu: split SolidRun CuBox into variants

From: Sebastian Hesselbarth
Date: Tue May 27 2014 - 17:50:41 EST


On 05/27/2014 11:35 PM, Jason Cooper wrote:
> On Tue, May 27, 2014 at 07:28:09PM +0200, Sebastian Hesselbarth wrote:
>> On 05/27/2014 06:11 PM, Jason Cooper wrote:
>>> On Mon, May 26, 2014 at 11:33:29PM +0200, Sebastian Hesselbarth wrote:
>>>> As Mainlining effort for SolidRun CuBox has been carried out on the
>>>> Engineering Sample, the board DTS was reflecting this. Actually,
>>>> SolidRun CuBox comes in three different variants: Engineering Sample (ES),
>>>> production with 1GB RAM (1G), and production with 2GB RAM (2G).
>>>>
>>>> Therefore, we split the current dove-cubox.dts into a common board include
>>>> and one board dts for each of the above variants.
>>>>
>>>> Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@xxxxxxxxx>
>>>> ---
>> [...]
>>>> ---
>>>> arch/arm/boot/dts/Makefile | 4 +++-
>>>> arch/arm/boot/dts/dove-cubox-1g.dts | 17 ++++++++++++++++
>>>> arch/arm/boot/dts/dove-cubox-2g.dts | 17 ++++++++++++++++
>>>> arch/arm/boot/dts/dove-cubox-es.dts | 23 ++++++++++++++++++++++
>>>> .../boot/dts/{dove-cubox.dts => dove-cubox.dtsi} | 17 ----------------
>>>> 5 files changed, 60 insertions(+), 18 deletions(-)
>>>> create mode 100644 arch/arm/boot/dts/dove-cubox-1g.dts
>>>> create mode 100644 arch/arm/boot/dts/dove-cubox-2g.dts
>>>> create mode 100644 arch/arm/boot/dts/dove-cubox-es.dts
>>>> rename arch/arm/boot/dts/{dove-cubox.dts => dove-cubox.dtsi} (86%)
>>>>
>> [...]
>>>> diff --git a/arch/arm/boot/dts/dove-cubox-2g.dts b/arch/arm/boot/dts/dove-cubox-2g.dts
>>>> new file mode 100644
>>>> index 000000000000..513b6a68eba3
>>>> --- /dev/null
>>>> +++ b/arch/arm/boot/dts/dove-cubox-2g.dts
>>>> @@ -0,0 +1,17 @@
>>>> +/dts-v1/;
>>>> +
>>>> +#include "dove-cubox.dtsi"
>>>> +
>>>> +/ {
>>>> + model = "SolidRun CuBox (2G)";
>>>> + compatible = "solidrun,cubox-2g", "solidrun,cubox", "marvell,dove";
>>>> +
>>>> + memory {
>>>> + device_type = "memory";
>>>> + reg = <0x00000000 0x80000000>;
>>>
>>> Do you anticipate any other differences between the 1G and the 2G?
>>> Otherwise, I'm inclined to just have a "solidrun,cubox". The bootloader
>>> should be setting the amount of RAM at boottime anyway.
>>
>> Given the minor differences between ES and production, instead of
>>
>> dove-cubox-common.dtsi
>> +--> dove-cubox.dts (production)
>> +--> dove-cubos-es.dts (engineering sample)
>>
>> we could also just have an "overlay" for the ES like
>>
>> dove-cubox.dts (production)
>> +--> dove-cubox-es.dts (engineering sample)
>>
>> It is not used commonly until now, maybe just a matter of taste.
>>
>> Is there any version you prefer?
>
> iiuc, overlays were intended for daughterboard (capes, etc) specific

Oh, ok. I guess "overlay" was misleading here. I did not mean dynamic
loading/unloading of dtb but including a dts from another dts.

> info. It may be useful here, but I'd like to hear from the DT
> maintainers how they want it used. eg: most popular first, like you
> have it, or oldest first
>
> dove-cubox-es.dts
> +--> dove-cubox.dts

In the cubox case, this is not possible. ES has a misrouted
card-detection for sdhci, this requires an additional property.
There is no way to remove a property once it is written down in
any of the files included. But you know about that already.

> There's also what to do with the older files using #include...
>
> In short, I'd prefer to stick to the old method until we have a good
> reason to move to overlays and a recommended way to execute that.*

Ok, the old method is straight forward and I keep that in mind. I'll
send a v2 of this using the approach we just talked about to eliminate
any misinterpretations. Just have a look and feel free to request an
"old-method" v3 immediately :P

Sebastian

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