Re: Raspberry Pi POE+ hat overlay

On Fri, 12 May 2023 at 17:38, Doug Rabson <[email protected]> wrote:

>
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> On Fri, 12 May 2023 at 17:27, Mark Millard <[email protected]> wrote:
>
>> On May 12, 2023, at 08:43, Doug Rabson <[email protected]> wrote:
>>
>> > I have a pi4 with the official POE+ hat which I want to run FreeBSD on.
>> One thing I noticed is that the fan doesn't run in FreeBSD so I decided to
>> try and write a little driver for it. First step seems to be to load the
>> corresponding devicetree overlay by adding something like this to
>> /boot/msdos/config.txt:
>> >
>> > dtoverlay=rpi-poe-plus
>> > dtparam=poe_fan_temp0=45000,dtparam=poe_fan_temp0_hyst=3000
>> > dtparam=poe_fan_temp1=50000,dtparam=poe_fan_temp1_hyst=3000
>> > dtparam=poe_fan_temp2=62000,dtparam=poe_fan_temp2_hyst=4000
>> > dtparam=poe_fan_temp3=70000,dtparam=poe_fan_temp3_hyst=5000
>> >
>> > Unfortunately this is where I'm stuck - the overlay is not present in
>> the final DTB given to the kernel so there isn't anything to hook a driver
>> to. Are dtoverlays supposed to work on FreeBSD?
>>
>> The RPi* firwmare version that FreeBSD has in ports and uses
>> in making snapshots and other images does not have that overlay:
>>
>> # ls -Tld /usr/local/share/rpi-firmware/overlays/rpi*
>> -rw-r--r--  1 root  wheel   489 Mar  3 05:29:57 2021
>> /usr/local/share/rpi-firmware/overlays/rpi-backlight.dtbo
>> -rw-r--r--  1 root  wheel  4081 Mar  3 05:29:57 2021
>> /usr/local/share/rpi-firmware/overlays/rpi-cirrus-wm5102.dtbo
>> -rw-r--r--  1 root  wheel   643 Mar  3 05:29:57 2021
>> /usr/local/share/rpi-firmware/overlays/rpi-dac.dtbo
>> -rw-r--r--  1 root  wheel  2574 Mar  3 05:29:57 2021
>> /usr/local/share/rpi-firmware/overlays/rpi-display.dtbo
>> -rw-r--r--  1 root  wheel   842 Mar  3 05:29:57 2021
>> /usr/local/share/rpi-firmware/overlays/rpi-ft5406.dtbo
>> -rw-r--r--  1 root  wheel  2937 Mar  3 05:29:57 2021
>> /usr/local/share/rpi-firmware/overlays/rpi-poe.dtbo
>> -rw-r--r--  1 root  wheel   771 Mar  3 05:29:57 2021
>> /usr/local/share/rpi-firmware/overlays/rpi-proto.dtbo
>> -rw-r--r--  1 root  wheel   893 Mar  3 05:29:57 2021
>> /usr/local/share/rpi-firmware/overlays/rpi-sense.dtbo
>> -rw-r--r--  1 root  wheel   567 Mar  3 05:29:57 2021
>> /usr/local/share/rpi-firmware/overlays/rpi-tv.dtbo
>> -rw-r--r--  1 root  wheel  1226 Mar  3 05:29:57 2021
>> /usr/local/share/rpi-firmware/overlays/rpivid-v4l2.dtbo
>>
>> You do not mention establishing a copy of overlays/rpi-poe-plus.dtbo .
>>
>
> I copied the file from a rasbian install I had for another project.
> Perhaps I should find the corresponding source for it and build it with the
> device tree source from FreeBSD.
>
>
>>
>> You also do not mention what version of FreeBSD you are using
>> on the RPi4B. The output of the command:
>>
>
> I'm running 13.2-RELEASE-p0
>

Ok, if I add the rpi-poe.dtbo file and change to using 'dtoverlay=rpi-poe',
then I do see the overlay in the booted system - thanks for all the
pointers. Looks like I need to figure out how to add rpi-poe-plus to the
rpi-firmware port first.


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