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I would like to know which document you found the "0xB000" offset of the IRQ peripheral. I'm studying more about the peripherals and I'd like to see how it is documented on the datasheets.

Thank you in advance.

Will this be updated to support the RPi 3 or 4? (I don’t have a 1 or 2)

There doesn't seem to be a license attached to either the tutorial or the code. So, it's unclear whether someone is allowed to build off of your tutorial kernel, or whether or not restrictions apply to the use & distribution of such derived works.

(I'd recommend slapping an MIT or BSD license on if you don't care, since those are the most permissive.)

Great tutorial and thank you.

I do have a question about testing on hardware. I have seen a few other "build from scratch" lessons like this and they all do the same thing when it comes to testing on actual hardware. The RP must have a Raspian OS already installed on the SD card and then the kernel.img file created in the tutorial overwrites a file on the SD Card. I come away feeling like we have not really created an OS from scratch. There are clearly other instruction files being loaded and executed before ours.

Is it not possible to create an SD Card that contains a tiny OS of our creation and is placed onto an SD Card with absolutely nothing else? My understanding is that the RP3/4 main processor, upon reset, looks to the SD card for the very first instructions that it must execute. Clearly, the instructions must appear at a very specific and fixed location on the SD card because the RP3/4 processor is not going to look for them in any other place. It may require some kind of very low-level formatting of the SD card. Nevertheless, why is this not possible?
Thank you,
Mark

Part 8 of the tutorial has a broken next link; im assuming a part 9 is in the works? :)

As you are updating this over time, an rss feed would be useful, to keep up with the rest of the guide as it is added. There is technically currently an rss feed, but it doesn't have any items in it, so it doesn't work.

I had an issue with the given

qemu-system-arm -m 256 -M raspi2 -serial stdio -kernel myos.elf
command in this tutorial. It output:
Unable to init server: Could not connect: Connection refused
gtk initialization failed

THE FIX:
changed "stdio" to "mon:stdio" and added "-nographic" option.

Full command that worked:

qemu-system-arm -m 256 -M raspi2 -serial mon:stdio -kernel myos.elf -nographic

Versions I'm using:
Linux 5.10.16.3-microsoft-standard-WSL2 x86_64
qemu-system-arm: 1:4.2-3ubuntu6.18

While setting up the development environment, (following this tutorial) when I run ./configure --target-list=arm-softmmu,arm-linux-user to configure QEMU, I get the following error:

ERROR: Unknown target name 'arm-softmmu'

Ubuntu 20.04

Please continue this. Its very interesting.