Discussion about linux-rpi rebrand

[quark]

gpu_mem=16 I think makes the Pi boot a different image file, with video disabled or something like that, not exactly sure.
There might be an issue in that area. To force the "normal" boot I think you need to have at least 32M for gpu_mem.
For the dtparam stuff maybe check the device tree file (decompile to dts) and see if there's any changes between before and after update.

So what is the deal with the RPi 2 exactly?

I noticed it used to be listed in the announcement:
$this->bbcode_second_pass_quote('', '
')linux-raspberrypi --> linux-rpi-legacy (RPi 1, 2, and Zero)
linux-raspberrypi4 --> linux-rpi (RPi 3, 4, 400, Zero W, and Zero 2 W

[graysky]

$this->bbcode_second_pass_quote('Semi', 'W')hat's the correct kernel for the RPi 2?

[keithspg]

@Semi I do not know which Pi2 you have, but as far as I can tell, there are 2 variants. I am not completely sure, but pretty sure it is only the Pi2 Rev 1.1 that actually 'requires' the armv7 32 bit OS/Kernel. I have this one and it will not boot the aarch64 image. I do not have one to confirm, but think the Pi2 version 1.2 will boot the aarch64 image.

We are developing an audio player based on Arch ARM and recommend using the v6 image for the A/B1and Zero, ZeroW, the armv7 image for the Pi2 v1.1 and the aarch64 for all others.
I can confirm that the aarch64 version boots on the 3B, 3B+, 4, Zero2W.

I am pretty sure it is covered here, but to get such an image, we install the basic aarch64 image according to the docs then after it is booted up and the pacman-init done, we install 'linux-rpi' pacjkage which uninstalls uboot and the latest linux kernel and installs the RPi kernel. When rebooted, it reboots to the RPi kernel.

[keithspg]

$this->bbcode_second_pass_quote('quark', 'g')pu_mem=16 I think makes the Pi boot a different image file, with video disabled or something like that, not exactly sure.
There might be an issue in that area. To force the "normal" boot I think you need to have at least 32M for gpu_mem.
For the dtparam stuff maybe check the device tree file (decompile to dts) and see if there's any changes between before and after update.

[keithspg]

So, to try to figure out what is going on, I used the PKGBUILD for the Arch kernel from here:
https://archlinuxarm.org/packages/armv6h/linux-rpi-legacy
but substituted a commit number from here:
https://github.com/raspberrypi/linux/tags
specifically, I used this:
$this->bbcode_second_pass_code('', '_commit=6a12ecfa52bf747678c41ef5a22cad5e73202c16
')
With a kernel package built from this commit, which I really cannot say which release it is, 'reboot' and 'gpu_mem=16' work on the Pi ZeroW. I have not looked at the Zero2W, yet, but this is encouraging.

It seems that the kernel we are currently using is broken, somehow. @graysky, does this help?

[graysky]

I haven't been following this thread very closely. I do not understand what is broken for you or why you want to use that old directive.

[keithspg]

@graysky Sorry to be so muddled. The recent update to the new kernels (linux-raspberrypi -> linux-rpi-legacy and linux-raspberrypi4 -> linux-rpi) has caused some things to break. It seems that the RPiOS people are also struggling to get everything working with the latest kernels...

Specifically the armv6 rpi-legacy kernel.
1) from the cli if you issue a reboot on a Pi Zero, it will not reboot.
2) If you set gpu_mem=16 on all armv6 devices, it will not boot.
3) The other issue which is apparent on both the armv6 (rpi-legacy) and and v7 (rpi) images is that the onboard audio (if present) is not enabled. I am not too sure if this is also present on the current RPiOS image or not as I have not checked. The aarch64 image runing on a 3b+ does enable the audio and it can be switched on and off in software so there was no change in the behavior for the official aaarch64 kernel.

When I rebuilt the kernel with that commit i mentioned above for rpi-legacy on armv6, I can 1) reboot from the command line and 2) can set gpu_mem=16 on both the Zero and Pi1 and have the Pis boot. I still have not dug into the missing onboard audio and when it disappeared or how it can be returned. On the aarch64 image, we have this set in config.txt: dtparam=audio=on. When we try that on the armv6 images, they fail to boot.

Hope this clears it up a bit as to what we are struggling with.

[quark]

I don't think aarch64 has support for dtparam/dtoverlay.
I'm currently trying to rebuild the aarch64 kernel with some audio stuff which is missing from the stock ALARM aarch64 config.
Also apart from the missing drivers, there's no entry for them in the config, and the device tree is also butchered/half put together. i2s almost completely missing. I think aarch64 is more on the experimental side at this point.

[keithspg]

$this->bbcode_second_pass_quote('quark', 'I') don't think aarch64 has support for dtparam/dtoverlay.
SNIP