Re: [PATCH 1/2] conf: machine: add BeagleBone Green Eco to KERNEL_DEVICETREE

[Ryan Eatmon <reatmon@ti.com>]

On 7/18/2025 4:54 AM, Miguel Gazquez wrote:
> 
> 
> Le 17/07/2025 à 20:01, Ryan Eatmon a écrit :
>>
>>
>> On 7/17/2025 12:55 PM, Miguel Gazquez wrote:
>>>
>>>
>>> Le 15/07/2025 à 15:52, Ryan Eatmon a écrit :
>>>>
>>>>
>>>> On 7/15/2025 6:34 AM, Miguel Gazquez wrote:
>>>>> Add am335x-bonegreen-eco devicetree to KERNEL_DEVICETREE in ti33x.inc
>>>>>
>>>>> Signed-off-by: Miguel Gazquez <miguel.gazquez@bootlin.com>
>>>>> ---
>>>>>   meta-ti-bsp/conf/machine/include/ti33x.inc | 1 +
>>>>>   1 file changed, 1 insertion(+)
>>>>>
>>>>> diff --git a/meta-ti-bsp/conf/machine/include/ti33x.inc b/meta-ti- 
>>>>> bsp/ conf/machine/include/ti33x.inc
>>>>> index 
>>>>> 7e9eb48c52737e74750565e639956334162432e2..0a0730eae104371d65548588b3333839857a3a50 100644
>>>>> --- a/meta-ti-bsp/conf/machine/include/ti33x.inc
>>>>> +++ b/meta-ti-bsp/conf/machine/include/ti33x.inc
>>>>> @@ -28,6 +28,7 @@ KERNEL_DEVICETREE = " \
>>>>>       ti/omap/am335x-boneblack.dtb \
>>>>>       ti/omap/am335x-boneblue.dtb \
>>>>>       ti/omap/am335x-bonegreen-wireless.dtb \
>>>>> +    ti/omap/am335x-bonegreen-eco.dtb \
>>>>>       ti/omap/am335x-bonegreen.dtb \
>>>>>       ti/omap/am335x-chiliboard.dtb \
>>>>>       ti/omap/am335x-cm-t335.dtb \
>>>>
>>>> NAK.  As has been mentioned several times on this list, we do not 
>>>> update KERNEL_DEVICETREE directly.  As we support multiple kernel 
>>>> versions with each branch, we cannot have a single KERNEL_DEVICETREE 
>>>> that works for all kernel versions.
>>>>
>>>> To that end we setup the KERNEL_DEVICETREE_PREFIX variable that will 
>>>> pattern match and change the value for KERNEL_DEVICETREE based on 
>>>> the available matching DTBs in the given kernel.  The only kernel 
>>>> version that uses KERNEL_DEVICETREE is the mainline (aka latest 
>>>> stable) kernel. And the value for this variable is automatically 
>>>> updated to include all of the available DTBs in the mainline kernel 
>>>> at the time we update the recipe to that version.
>>>>
>>>> As the KERNEL_DEVICETREE_PREFIX already has an entry that will pick 
>>>> up this new DTB when it is available, this change is not needed.
>>>
>>> When building for the am335x_evm without this patch, the devicetree 
>>> for the beaglebone green eco is not included in the wic image, so the 
>>> kernel can't boot.
>>>
>>> As you said, in the linux-ti-staging recipe, KERNEL_DEVICETREE does 
>>> contains the dtb for the bbg eco.
>>>
>>> But core-image-minimal (which create the wic image) uses the value of 
>>> KERNEL_DEVICETREE from ti33x.inc, and not the one generated from 
>>> KERNEL_DEVICETREE_PREFIX, so it doesn't contains the devicetree for 
>>> the bbge. This can be checked with `bitbake-getvar -r core-image- 
>>> minimal KERNEL_DEVICETREE`.
>>>
>>> It probably works for others boards because, apart from the bbge, 
>>> there isn't any board supported in ti-linux-6.12.y but not in mainline.
>>>
>>> If we can't modify KERNEL_DEVICETREE here, what should I do to 
>>> include the devicetree into the final image ?
>>
>> Are you talking about a poky build with a poky kernel?  Or a poky 
>> build with the TI kernel?
>>
>> If you are talking about the TI kernel, then the mainline recipe does 
>> not point to a kernel that has this DTB.  So are you trying to use the 
>> mainline recipe but change the SRCREV to point a commit that does 
>> contain this new DTB file?
> 
> I'm using a poky build with the TI kernel, which by default uses the 
> branch "ti-linux-6.12.y", with the SRCREV equal to 
> "78e6abff322081d53c5a685d927476086c9b2846" (on the scarthgap branch, I 
> forgot to mention it). And on this branch there is the commit 
> "ab7f0d695e9a3268deb760dcd0fa58812a614cd8" adding the devicetree for the 
> beaglebone green eco.

If you are on scarthgap and using linux-ti-staging_6.12, then you should 
just need to point to the appropriate SRCREV for the patch you want and 
build am335x-evm.  That should build the deploy the dtb you are looking 
for.  It is in our nightly builds.

In fact, we just promoted our CICD and I can see the file of interest in 
our build.  So you should not even need to change the SRCREV if you use 
the latest scarthgap.

> 
>>>>
>>>> Right now this new DTB is only available on linux-next and has not 
>>>> made it into any released kernels.
>>>>
>>>>
>>>
>>
> 

-- 
Ryan Eatmon                reatmon@ti.com
-----------------------------------------
Texas Instruments, Inc.  -  LCPD  -  MGTS