Custom device tree overlay for BBB

Custom device tree overlay for BBB

[Lukasz Przenioslo]

Hello there,

I was able to compile the Poky image (Dunfell) with meta-ti included for the BBB. I am working on an open source project intended for home automation based on the BBB: https://github.com/Beaglenode/BeagleNodeHW

The next step I am trying to make is to prepare a proper device tree overlay that would align with the HW requirements of this project (or "cape"). I need to:
- Disable the HDMI pins,
- configure multiple pins as either PRU0 or PRU1 controlled.

For that I thought the best approach would be to prepare a DTO, instead of modifying the default one for BBB. I don't know how to prepare that DTO yet and I don't know how to include it in my build. I would like to ask for some help in this manner, especially the prior part (how to load the custom DTO). Right now I am still modifying everything in the local.conf, as I do not have the knowledge yet to build my own distro for this device (that's the end plan).

I would appreciate all help!

Re: [meta-ti] Custom device tree overlay for BBB

[Jon Cormier]

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Here is a possible example overlay that configures pinmuxes with the
expectation that the pru's will use them.  There is likely a similar
example in that long list of overlays that disables hdmi.

https://github.com/beagleboard/bb.org-overlays/blob/master/src/arm/AM335X-PRU-RPROC-4-19-TI-PRUCAPE-00A0.dts

Note its entirely possible these examples won't build or apply correctly on
a different kernel version, but they should still be a decent starting
point.

On Thu, Dec 21, 2023 at 6:34 AM Lukasz Przenioslo <bremenpl@gmail.com>
wrote:

> Hello there,
>
> I was able to compile the Poky image (Dunfell) with meta-ti included for
> the BBB. I am working on an open source project intended for home
> automation based on the BBB: https://github.com/Beaglenode/BeagleNodeHW
>
> The next step I am trying to make is to prepare a proper device tree
> overlay that would align with the HW requirements of this project (or
> "cape"). I need to:
> - Disable the HDMI pins,
> - configure multiple pins as either PRU0 or PRU1 controlled.
>
> For that I thought the best approach would be to prepare a DTO, instead of
> modifying the default one for BBB. I don't know how to prepare that DTO yet
> and I don't know how to include it in my build. I would like to ask for
> some help in this manner, especially the prior part (how to load the custom
> DTO). Right now I am still modifying everything in the local.conf, as I do
> not have the knowledge yet to build my own distro for this device (that's
> the end plan).
>
> I would appreciate all help!
>
> -=-=-=-=-=-=-=-=-=-=-=-
> Links: You receive all messages sent to this group.
> View/Reply Online (#17360):
> https://lists.yoctoproject.org/g/meta-ti/message/17360
> Mute This Topic: https://lists.yoctoproject.org/mt/103298715/7902621
> Group Owner: meta-ti+owner@lists.yoctoproject.org
> Unsubscribe: https://lists.yoctoproject.org/g/meta-ti/unsub [
> jcormier@criticallink.com]
> -=-=-=-=-=-=-=-=-=-=-=-
>
>

-- 
Jonathan Cormier
Software Engineer

Voice:  315.425.4045 x222



http://www.CriticalLink.com <http://www.criticallink.com/>
6712 Brooklawn Parkway, Syracuse, NY 13211

<https://www.linkedin.com/company/critical-link-llc>
<https://twitter.com/Critical_Link>

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Re: [meta-ti] Custom device tree overlay for BBB

[Bremenpl]

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Hi and thank you for the answer Jonathan!

Do you happen to also know a good reference on how to incorporate an 
overlay into the yocto build?

On December 21, 2023 15:58:56 Jon Cormier <jcormier@criticallink.com> wrote:
> Here is a possible example overlay that configures pinmuxes with the 
> expectation that the pru's will use them.  There is likely a similar 
> example in that long list of overlays that disables hdmi.
>
>
> https://github.com/beagleboard/bb.org-overlays/blob/master/src/arm/AM335X-PRU-RPROC-4-19-TI-PRUCAPE-00A0.dts
>
> Note its entirely possible these examples won't build or apply correctly on 
> a different kernel version, but they should still be a decent starting point.
>
>
>
> On Thu, Dec 21, 2023 at 6:34 AM Lukasz Przenioslo <bremenpl@gmail.com> wrote:
>
> Hello there,
>
> I was able to compile the Poky image (Dunfell) with meta-ti included for 
> the BBB. I am working on an open source project intended for home 
> automation based on the BBB: https://github.com/Beaglenode/BeagleNodeHW
>
> The next step I am trying to make is to prepare a proper device tree 
> overlay that would align with the HW requirements of this project (or 
> "cape"). I need to:
> - Disable the HDMI pins,
> - configure multiple pins as either PRU0 or PRU1 controlled.
>
> For that I thought the best approach would be to prepare a DTO, instead of 
> modifying the default one for BBB. I don't know how to prepare that DTO yet 
> and I don't know how to include it in my build. I would like to ask for 
> some help in this manner, especially the prior part (how to load the custom 
> DTO). Right now I am still modifying everything in the local.conf, as I do 
> not have the knowledge yet to build my own distro for this device (that's 
> the end plan).
>
> I would appreciate all help!
>
> -=-=-=-=-=-=-=-=-=-=-=-
> Links: You receive all messages sent to this group.
> View/Reply Online (#17360): 
> https://lists.yoctoproject.org/g/meta-ti/message/17360
> Mute This Topic: https://lists.yoctoproject.org/mt/103298715/7902621
> Group Owner: meta-ti+owner@lists.yoctoproject.org
> Unsubscribe: https://lists.yoctoproject.org/g/meta-ti/unsub 
> [jcormier@criticallink.com]
> -=-=-=-=-=-=-=-=-=-=-=-
>
>
>
>
> --
>
> Jonathan Cormier
> Software Engineer
>
> Voice:  315.425.4045 x222
>
>
>
>
>
>
> http://www.CriticalLink.com
>
> 6712 Brooklawn Parkway, Syracuse, NY 13211


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Re: [meta-ti] Custom device tree overlay for BBB

[Jon Cormier]

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This solution seems like a good place to start. I haven't tried it myself
but it looks clean and easy to implement.
https://stackoverflow.com/a/68650774

The alternative would be to bbappend the kernel and patch your overlay into
the correct folder.
https://stackoverflow.com/a/39343720

On Thu, Dec 21, 2023 at 10:03 AM Bremenpl <bremenpl@gmail.com> wrote:

> Hi and thank you for the answer Jonathan!
>
> Do you happen to also know a good reference on how to incorporate an
> overlay into the yocto build?
>
> On December 21, 2023 15:58:56 Jon Cormier <jcormier@criticallink.com>
> wrote:
>
>> Here is a possible example overlay that configures pinmuxes with the
>> expectation that the pru's will use them.  There is likely a similar
>> example in that long list of overlays that disables hdmi.
>>
>>
>> https://github.com/beagleboard/bb.org-overlays/blob/master/src/arm/AM335X-PRU-RPROC-4-19-TI-PRUCAPE-00A0.dts
>>
>> Note its entirely possible these examples won't build or apply correctly
>> on a different kernel version, but they should still be a decent starting
>> point.
>>
>> On Thu, Dec 21, 2023 at 6:34 AM Lukasz Przenioslo <bremenpl@gmail.com>
>> wrote:
>>
>>> Hello there,
>>>
>>> I was able to compile the Poky image (Dunfell) with meta-ti included for
>>> the BBB. I am working on an open source project intended for home
>>> automation based on the BBB: https://github.com/Beaglenode/BeagleNodeHW
>>>
>>> The next step I am trying to make is to prepare a proper device tree
>>> overlay that would align with the HW requirements of this project (or
>>> "cape"). I need to:
>>> - Disable the HDMI pins,
>>> - configure multiple pins as either PRU0 or PRU1 controlled.
>>>
>>> For that I thought the best approach would be to prepare a DTO, instead
>>> of modifying the default one for BBB. I don't know how to prepare that DTO
>>> yet and I don't know how to include it in my build. I would like to ask for
>>> some help in this manner, especially the prior part (how to load the custom
>>> DTO). Right now I am still modifying everything in the local.conf, as I do
>>> not have the knowledge yet to build my own distro for this device (that's
>>> the end plan).
>>>
>>> I would appreciate all help!
>>>
>>> -=-=-=-=-=-=-=-=-=-=-=-
>>> Links: You receive all messages sent to this group.
>>> View/Reply Online (#17360):
>>> https://lists.yoctoproject.org/g/meta-ti/message/17360
>>> Mute This Topic: https://lists.yoctoproject.org/mt/103298715/7902621
>>> Group Owner: meta-ti+owner@lists.yoctoproject.org
>>> Unsubscribe: https://lists.yoctoproject.org/g/meta-ti/unsub [
>>> jcormier@criticallink.com]
>>> -=-=-=-=-=-=-=-=-=-=-=-
>>>
>>>
>>
>> --
>> Jonathan Cormier
>> Software Engineer
>>
>> Voice:  315.425.4045 x222
>>
>>
>>
>> http://www.CriticalLink.com <http://www.criticallink.com/>
>> 6712 Brooklawn Parkway, Syracuse, NY 13211
>>
>> <https://www.linkedin.com/company/critical-link-llc>
>> <https://twitter.com/Critical_Link>
>>
>
>

-- 
Jonathan Cormier
Software Engineer

Voice:  315.425.4045 x222



http://www.CriticalLink.com <http://www.criticallink.com/>
6712 Brooklawn Parkway, Syracuse, NY 13211

<https://www.linkedin.com/company/critical-link-llc>
<https://twitter.com/Critical_Link>

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Re[2]: [meta-ti] Custom device tree overlay for BBB

[Łukasz Przeniosło]

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Hi Jon,
I guess the first option is more feasible, as I would not like to modify 
any files provided by the Poky repo, but rather create my own recipe 
that would somehow cover the default settings during the build. There is 
still a lot ahead for me to understand though...

Thank you for the useful links.

--
Łukasz Przeniosło


------ Original Message ------
From "Jon Cormier" <jcormier@criticallink.com>
To "Bremenpl" <bremenpl@gmail.com>
Cc meta-ti@lists.yoctoproject.org
Date 2023-12-21 16:17:38
Subject Re: [meta-ti] Custom device tree overlay for BBB

>This solution seems like a good place to start. I haven't tried it 
>myself but it looks clean and easy to implement.
>https://stackoverflow.com/a/68650774
>
>The alternative would be to bbappend the kernel and patch your overlay 
>into the correct folder.
>https://stackoverflow.com/a/39343720
>
>On Thu, Dec 21, 2023 at 10:03 AM Bremenpl <bremenpl@gmail.com> wrote:
>>Hi and thank you for the answer Jonathan!
>>
>>Do you happen to also know a good reference on how to incorporate an 
>>overlay into the yocto build?
>>
>>On December 21, 2023 15:58:56 Jon Cormier <jcormier@criticallink.com> 
>>wrote:
>>
>>>Here is a possible example overlay that configures pinmuxes with the 
>>>expectation that the pru's will use them.  There is likely a similar 
>>>example in that long list of overlays that disables hdmi.
>>>
>>>https://github.com/beagleboard/bb.org-overlays/blob/master/src/arm/AM335X-PRU-RPROC-4-19-TI-PRUCAPE-00A0.dts
>>>
>>>Note its entirely possible these examples won't build or apply 
>>>correctly on a different kernel version, but they should still be a 
>>>decent starting point.
>>>
>>>On Thu, Dec 21, 2023 at 6:34 AM Lukasz Przenioslo 
>>><bremenpl@gmail.com> wrote:
>>>>Hello there,
>>>>
>>>>I was able to compile the Poky image (Dunfell) with meta-ti included 
>>>>for the BBB. I am working on an open source project intended for 
>>>>home automation based on the BBB: 
>>>>https://github.com/Beaglenode/BeagleNodeHW
>>>>
>>>>The next step I am trying to make is to prepare a proper device tree 
>>>>overlay that would align with the HW requirements of this project 
>>>>(or "cape"). I need to:
>>>>- Disable the HDMI pins,
>>>>- configure multiple pins as either PRU0 or PRU1 controlled.
>>>>
>>>>For that I thought the best approach would be to prepare a DTO, 
>>>>instead of modifying the default one for BBB. I don't know how to 
>>>>prepare that DTO yet and I don't know how to include it in my build. 
>>>>I would like to ask for some help in this manner, especially the 
>>>>prior part (how to load the custom DTO). Right now I am still 
>>>>modifying everything in the local.conf, as I do not have the 
>>>>knowledge yet to build my own distro for this device (that's the end 
>>>>plan).
>>>>
>>>>I would appreciate all help!
>>>>
>>>>-=-=-=-=-=-=-=-=-=-=-=-
>>>>Links: You receive all messages sent to this group.
>>>>View/Reply Online (#17360): 
>>>>https://lists.yoctoproject.org/g/meta-ti/message/17360
>>>>Mute This Topic: https://lists.yoctoproject.org/mt/103298715/7902621
>>>>Group Owner: meta-ti+owner@lists.yoctoproject.org 
>>>><mailto:meta-ti%2Bowner@lists.yoctoproject.org>
>>>>Unsubscribe: https://lists.yoctoproject.org/g/meta-ti/unsub 
>>>>[jcormier@criticallink.com]
>>>>-=-=-=-=-=-=-=-=-=-=-=-
>>>>
>>>
>>>
>>>--
>>>Jonathan Cormier
>>>Software Engineer
>>>
>>>Voice:  315.425.4045 x222
>>>
>>>
>>>
>>>http://www.CriticalLink.com <http://www.criticallink.com/>
>>>6712 Brooklawn Parkway, Syracuse, NY 13211
>>>
>>><https://www.linkedin.com/company/critical-link-llc>   
>>><https://twitter.com/Critical_Link>
>>
>
>
>--
>Jonathan Cormier
>Software Engineer
>
>Voice:  315.425.4045 x222
>
>
>
>http://www.CriticalLink.com <http://www.criticallink.com/>
>6712 Brooklawn Parkway, Syracuse, NY 13211
>
><https://www.linkedin.com/company/critical-link-llc>   
><https://twitter.com/Critical_Link>

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Re: [meta-ti] Custom device tree overlay for BBB

[Denys Dmytriyenko]

You could simply add your overlay in one of the conf files, such as 
local.conf:

KERNEL_DEVICETREE += "your-overlay.dtbo"

Check the existing machine conf files for examples.


On Thu, Dec 21, 2023 at 08:51:49PM +0000, Lukasz Przenioslo wrote:
> Hi Jon,
> I guess the first option is more feasible, as I would not like to
> modify any files provided by the Poky repo, but rather create my own
> recipe that would somehow cover the default settings during the
> build. There is still a lot ahead for me to understand though...
> 
> Thank you for the useful links.
> 
> --
> Łukasz Przeniosło
> 
> 
> ------ Original Message ------
> From "Jon Cormier" <jcormier@criticallink.com>
> To "Bremenpl" <bremenpl@gmail.com>
> Cc meta-ti@lists.yoctoproject.org
> Date 2023-12-21 16:17:38
> Subject Re: [meta-ti] Custom device tree overlay for BBB
> 
> >This solution seems like a good place to start. I haven't tried it
> >myself but it looks clean and easy to implement.
> >https://stackoverflow.com/a/68650774
> >
> >The alternative would be to bbappend the kernel and patch your
> >overlay into the correct folder.
> >https://stackoverflow.com/a/39343720
> >
> >On Thu, Dec 21, 2023 at 10:03 AM Bremenpl <bremenpl@gmail.com> wrote:
> >>Hi and thank you for the answer Jonathan!
> >>
> >>Do you happen to also know a good reference on how to
> >>incorporate an overlay into the yocto build?
> >>
> >>On December 21, 2023 15:58:56 Jon Cormier
> >><jcormier@criticallink.com> wrote:
> >>
> >>>Here is a possible example overlay that configures pinmuxes
> >>>with the expectation that the pru's will use them.  There is
> >>>likely a similar example in that long list of overlays that
> >>>disables hdmi.
> >>>
> >>>https://github.com/beagleboard/bb.org-overlays/blob/master/src/arm/AM335X-PRU-RPROC-4-19-TI-PRUCAPE-00A0.dts
> >>>
> >>>Note its entirely possible these examples won't build or apply
> >>>correctly on a different kernel version, but they should still
> >>>be a decent starting point.
> >>>
> >>>On Thu, Dec 21, 2023 at 6:34 AM Lukasz Przenioslo
> >>><bremenpl@gmail.com> wrote:
> >>>>Hello there,
> >>>>
> >>>>I was able to compile the Poky image (Dunfell) with meta-ti
> >>>>included for the BBB. I am working on an open source project
> >>>>intended for home automation based on the BBB:
> >>>>https://github.com/Beaglenode/BeagleNodeHW
> >>>>
> >>>>The next step I am trying to make is to prepare a proper
> >>>>device tree overlay that would align with the HW
> >>>>requirements of this project (or "cape"). I need to:
> >>>>- Disable the HDMI pins,
> >>>>- configure multiple pins as either PRU0 or PRU1 controlled.
> >>>>
> >>>>For that I thought the best approach would be to prepare a
> >>>>DTO, instead of modifying the default one for BBB. I don't
> >>>>know how to prepare that DTO yet and I don't know how to
> >>>>include it in my build. I would like to ask for some help in
> >>>>this manner, especially the prior part (how to load the
> >>>>custom DTO). Right now I am still modifying everything in
> >>>>the local.conf, as I do not have the knowledge yet to build
> >>>>my own distro for this device (that's the end plan).
> >>>>
> >>>>I would appreciate all help!
> >>>>
> >>>>

Re: [meta-ti] Custom device tree overlay for BBB

[Bremenpl]

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Hi Denys,
Should be easy enough to test it quickly as a proof of concept, thank you. 
Will bitbake know to compile this overlay, tell the u-boot to load it and 
so on?

On December 22, 2023 02:49:39 Denys Dmytriyenko <denis@denix.org> wrote:

> You could simply add your overlay in one of the conf files, such as
> local.conf:
>
> KERNEL_DEVICETREE += "your-overlay.dtbo"
>
> Check the existing machine conf files for examples.
>
>
> On Thu, Dec 21, 2023 at 08:51:49PM +0000, Lukasz Przenioslo wrote:
>> Hi Jon,
>> I guess the first option is more feasible, as I would not like to
>> modify any files provided by the Poky repo, but rather create my own
>> recipe that would somehow cover the default settings during the
>> build. There is still a lot ahead for me to understand though...
>>
>> Thank you for the useful links.
>>
>> --
>> Łukasz Przeniosło
>>
>>
>> ------ Original Message ------
>> From "Jon Cormier" <jcormier@criticallink.com>
>> To "Bremenpl" <bremenpl@gmail.com>
>> Cc meta-ti@lists.yoctoproject.org
>> Date 2023-12-21 16:17:38
>> Subject Re: [meta-ti] Custom device tree overlay for BBB
>>
>> >This solution seems like a good place to start. I haven't tried it
>> >myself but it looks clean and easy to implement.
>> >https://stackoverflow.com/a/68650774
>> >
>> >The alternative would be to bbappend the kernel and patch your
>> >overlay into the correct folder.
>> >https://stackoverflow.com/a/39343720
>> >
>> >On Thu, Dec 21, 2023 at 10:03 AM Bremenpl <bremenpl@gmail.com> wrote:
>> >>Hi and thank you for the answer Jonathan!
>> >>
>> >>Do you happen to also know a good reference on how to
>> >>incorporate an overlay into the yocto build?
>> >>
>> >>On December 21, 2023 15:58:56 Jon Cormier
>> >><jcormier@criticallink.com> wrote:
>> >>
>> >>>Here is a possible example overlay that configures pinmuxes
>> >>>with the expectation that the pru's will use them.  There is
>> >>>likely a similar example in that long list of overlays that
>> >>>disables hdmi.
>> >>>
>> >>>https://github.com/beagleboard/bb.org-overlays/blob/master/src/arm/AM335X-PRU-RPROC-4-19-TI-PRUCAPE-00A0.dts
>> >>>
>> >>>Note its entirely possible these examples won't build or apply
>> >>>correctly on a different kernel version, but they should still
>> >>>be a decent starting point.
>> >>>
>> >>>On Thu, Dec 21, 2023 at 6:34 AM Lukasz Przenioslo
>> >>><bremenpl@gmail.com> wrote:
>> >>>>Hello there,
>> >>>>
>> >>>>I was able to compile the Poky image (Dunfell) with meta-ti
>> >>>>included for the BBB. I am working on an open source project
>> >>>>intended for home automation based on the BBB:
>> >>>>https://github.com/Beaglenode/BeagleNodeHW
>> >>>>
>> >>>>The next step I am trying to make is to prepare a proper
>> >>>>device tree overlay that would align with the HW
>> >>>>requirements of this project (or "cape"). I need to:
>> >>>>- Disable the HDMI pins,
>> >>>>- configure multiple pins as either PRU0 or PRU1 controlled.
>> >>>>
>> >>>>For that I thought the best approach would be to prepare a
>> >>>>DTO, instead of modifying the default one for BBB. I don't
>> >>>>know how to prepare that DTO yet and I don't know how to
>> >>>>include it in my build. I would like to ask for some help in
>> >>>>this manner, especially the prior part (how to load the
>> >>>>custom DTO). Right now I am still modifying everything in
>> >>>>the local.conf, as I do not have the knowledge yet to build
>> >>>>my own distro for this device (that's the end plan).
>> >>>>
>> >>>>I would appreciate all help!
>> >>>>
>> >>>>


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Re: [meta-ti] Custom device tree overlay for BBB

[Denys Dmytriyenko]

Sorry, this got a bit out of context - one of the solutions from Jon was 
talking about adding a bbappend to a kernel recipe, which would then 
automatically handle KERNEL_DEVICETREE list via kernel-devicetree,bbclass

Alternatively, if you add a standalne recipe, all you need is to add your 
overlay to SRC_URI and inherit devicetree.bbclass


On Fri, Dec 22, 2023 at 06:14:51AM +0100, Lukasz Przenioslo wrote:
> Hi Denys,
> Should be easy enough to test it quickly as a proof of concept,
> thank you. Will bitbake know to compile this overlay, tell the
> u-boot to load it and so on?
> 
> On December 22, 2023 02:49:39 Denys Dmytriyenko <denis@denix.org> wrote:
> 
> >You could simply add your overlay in one of the conf files, such as
> >local.conf:
> >
> >KERNEL_DEVICETREE += "your-overlay.dtbo"
> >
> >Check the existing machine conf files for examples.
> >
> >
> >On Thu, Dec 21, 2023 at 08:51:49PM +0000, Lukasz Przenioslo wrote:
> >>Hi Jon,
> >>I guess the first option is more feasible, as I would not like to
> >>modify any files provided by the Poky repo, but rather create my own
> >>recipe that would somehow cover the default settings during the
> >>build. There is still a lot ahead for me to understand though...
> >>
> >>Thank you for the useful links.
> >>
> >>--
> >>Łukasz Przeniosło
> >>
> >>
> >>------ Original Message ------
> >>From "Jon Cormier" <jcormier@criticallink.com>
> >>To "Bremenpl" <bremenpl@gmail.com>
> >>Cc meta-ti@lists.yoctoproject.org
> >>Date 2023-12-21 16:17:38
> >>Subject Re: [meta-ti] Custom device tree overlay for BBB
> >>
> >>>This solution seems like a good place to start. I haven't tried it
> >>>myself but it looks clean and easy to implement.
> >>>https://stackoverflow.com/a/68650774
> >>>
> >>>The alternative would be to bbappend the kernel and patch your
> >>>overlay into the correct folder.
> >>>https://stackoverflow.com/a/39343720
> >>>
> >>>On Thu, Dec 21, 2023 at 10:03 AM Bremenpl <bremenpl@gmail.com> wrote:
> >>>>Hi and thank you for the answer Jonathan!
> >>>>
> >>>>Do you happen to also know a good reference on how to
> >>>>incorporate an overlay into the yocto build?
> >>>>
> >>>>On December 21, 2023 15:58:56 Jon Cormier
> >>>><jcormier@criticallink.com> wrote:
> >>>>
> >>>>>Here is a possible example overlay that configures pinmuxes
> >>>>>with the expectation that the pru's will use them.  There is
> >>>>>likely a similar example in that long list of overlays that
> >>>>>disables hdmi.
> >>>>>
> >>>>>https://github.com/beagleboard/bb.org-overlays/blob/master/src/arm/AM335X-PRU-RPROC-4-19-TI-PRUCAPE-00A0.dts
> >>>>>
> >>>>>Note its entirely possible these examples won't build or apply
> >>>>>correctly on a different kernel version, but they should still
> >>>>>be a decent starting point.
> >>>>>
> >>>>>On Thu, Dec 21, 2023 at 6:34 AM Lukasz Przenioslo
> >>>>><bremenpl@gmail.com> wrote:
> >>>>>>Hello there,
> >>>>>>
> >>>>>>I was able to compile the Poky image (Dunfell) with meta-ti
> >>>>>>included for the BBB. I am working on an open source project
> >>>>>>intended for home automation based on the BBB:
> >>>>>>https://github.com/Beaglenode/BeagleNodeHW
> >>>>>>
> >>>>>>The next step I am trying to make is to prepare a proper
> >>>>>>device tree overlay that would align with the HW
> >>>>>>requirements of this project (or "cape"). I need to:
> >>>>>>- Disable the HDMI pins,
> >>>>>>- configure multiple pins as either PRU0 or PRU1 controlled.
> >>>>>>
> >>>>>>For that I thought the best approach would be to prepare a
> >>>>>>DTO, instead of modifying the default one for BBB. I don't
> >>>>>>know how to prepare that DTO yet and I don't know how to
> >>>>>>include it in my build. I would like to ask for some help in
> >>>>>>this manner, especially the prior part (how to load the
> >>>>>>custom DTO). Right now I am still modifying everything in
> >>>>>>the local.conf, as I do not have the knowledge yet to build
> >>>>>>my own distro for this device (that's the end plan).
> >>>>>>
> >>>>>>I would appreciate all help!
> >>>>>>
> >>>>>>

Re[2]: [meta-ti] Custom device tree overlay for BBB

[Łukasz Przeniosło]

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Thanks for the follow up Denys,
It's difficult for me to derive optimal solutions here, as I am only 
learning the Yocto environment. Eventually I would like to create a 
"custom OS" that would just build all needed ecosystem for the end 
device.

At this point I am trying to make a proof of concept approach in which I 
(via device tree overlay) will be able to deinitialize the HDMI pins and 
configure at least one pin as a PRU mapped (mode 5 or 6 if I recall 
correctly).

I will try to make something out of your's and Jon's answers for that 
end. Thank you again.

--
Łukasz Przeniosło


------ Original Message ------
From "Denys Dmytriyenko" <denis@denix.org>
To "Lukasz Przenioslo" <bremenpl@gmail.com>
Cc "Jon Cormier" <jcormier@criticallink.com>; 
meta-ti@lists.yoctoproject.org
Date 2023-12-22 08:03:56
Subject Re: [meta-ti] Custom device tree overlay for BBB

>Sorry, this got a bit out of context - one of the solutions from Jon was
>talking about adding a bbappend to a kernel recipe, which would then
>automatically handle KERNEL_DEVICETREE list via kernel-devicetree,bbclass
>
>Alternatively, if you add a standalne recipe, all you need is to add your
>overlay to SRC_URI and inherit devicetree.bbclass
>
>
>On Fri, Dec 22, 2023 at 06:14:51AM +0100, Lukasz Przenioslo wrote:
>>  Hi Denys,
>>  Should be easy enough to test it quickly as a proof of concept,
>>  thank you. Will bitbake know to compile this overlay, tell the
>>  u-boot to load it and so on?
>>
>>  On December 22, 2023 02:49:39 Denys Dmytriyenko <denis@denix.org> wrote:
>>
>>  >You could simply add your overlay in one of the conf files, such as
>>  >local.conf:
>>  >
>>  >KERNEL_DEVICETREE += "your-overlay.dtbo"
>>  >
>>  >Check the existing machine conf files for examples.
>>  >
>>  >
>>  >On Thu, Dec 21, 2023 at 08:51:49PM +0000, Lukasz Przenioslo wrote:
>>  >>Hi Jon,
>>  >>I guess the first option is more feasible, as I would not like to
>>  >>modify any files provided by the Poky repo, but rather create my own
>>  >>recipe that would somehow cover the default settings during the
>>  >>build. There is still a lot ahead for me to understand though...
>>  >>
>>  >>Thank you for the useful links.
>>  >>
>>  >>--
>>  >>Łukasz Przeniosło
>>  >>
>>  >>
>>  >>------ Original Message ------
>>  >>From "Jon Cormier" <jcormier@criticallink.com>
>>  >>To "Bremenpl" <bremenpl@gmail.com>
>>  >>Cc meta-ti@lists.yoctoproject.org
>>  >>Date 2023-12-21 16:17:38
>>  >>Subject Re: [meta-ti] Custom device tree overlay for BBB
>>  >>
>>  >>>This solution seems like a good place to start. I haven't tried it
>>  >>>myself but it looks clean and easy to implement.
>>  >>>https://stackoverflow.com/a/68650774
>>  >>>
>>  >>>The alternative would be to bbappend the kernel and patch your
>>  >>>overlay into the correct folder.
>>  >>>https://stackoverflow.com/a/39343720
>>  >>>
>>  >>>On Thu, Dec 21, 2023 at 10:03 AM Bremenpl <bremenpl@gmail.com> wrote:
>>  >>>>Hi and thank you for the answer Jonathan!
>>  >>>>
>>  >>>>Do you happen to also know a good reference on how to
>>  >>>>incorporate an overlay into the yocto build?
>>  >>>>
>>  >>>>On December 21, 2023 15:58:56 Jon Cormier
>>  >>>><jcormier@criticallink.com> wrote:
>>  >>>>
>>  >>>>>Here is a possible example overlay that configures pinmuxes
>>  >>>>>with the expectation that the pru's will use them.  There is
>>  >>>>>likely a similar example in that long list of overlays that
>>  >>>>>disables hdmi.
>>  >>>>>
>>  >>>>>https://github.com/beagleboard/bb.org-overlays/blob/master/src/arm/AM335X-PRU-RPROC-4-19-TI-PRUCAPE-00A0.dts
>>  >>>>>
>>  >>>>>Note its entirely possible these examples won't build or apply
>>  >>>>>correctly on a different kernel version, but they should still
>>  >>>>>be a decent starting point.
>>  >>>>>
>>  >>>>>On Thu, Dec 21, 2023 at 6:34 AM Lukasz Przenioslo
>>  >>>>><bremenpl@gmail.com> wrote:
>>  >>>>>>Hello there,
>>  >>>>>>
>>  >>>>>>I was able to compile the Poky image (Dunfell) with meta-ti
>>  >>>>>>included for the BBB. I am working on an open source project
>>  >>>>>>intended for home automation based on the BBB:
>>  >>>>>>https://github.com/Beaglenode/BeagleNodeHW
>>  >>>>>>
>>  >>>>>>The next step I am trying to make is to prepare a proper
>>  >>>>>>device tree overlay that would align with the HW
>>  >>>>>>requirements of this project (or "cape"). I need to:
>>  >>>>>>- Disable the HDMI pins,
>>  >>>>>>- configure multiple pins as either PRU0 or PRU1 controlled.
>>  >>>>>>
>>  >>>>>>For that I thought the best approach would be to prepare a
>>  >>>>>>DTO, instead of modifying the default one for BBB. I don't
>>  >>>>>>know how to prepare that DTO yet and I don't know how to
>>  >>>>>>include it in my build. I would like to ask for some help in
>>  >>>>>>this manner, especially the prior part (how to load the
>>  >>>>>>custom DTO). Right now I am still modifying everything in
>>  >>>>>>the local.conf, as I do not have the knowledge yet to build
>>  >>>>>>my own distro for this device (that's the end plan).
>>  >>>>>>
>>  >>>>>>I would appreciate all help!
>>  >>>>>>
>>  >>>>>>

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