On Sat, 2021-06-12 at 09:00 +0200, Ralph Aichinger wrote: > "All Raspberry Pi models before the 4 (1A, 1B, 1A+, 1B+, Zero, Zero > W, > 2, 3) boot from their GPU" > > So it seems this is no longer true, and exactly what I said.
I'm fairly sure that the RPi4 still boots via the VC4 chip, but I cannot find any proper documentation of the RPi4 SoC boot ROM like one can normally find with other SoCs. The official docs only say that the boot process is no different to older RPi hardware with the exception of there being an EEPROM involved. https://github.com/raspberrypi/documentation/blob/master/hardware/raspberrypi/bootmodes/bootflow_2711.md https://hackaday.io/page/6372-raspberry-pi-4-boot-sequence > If there are Blobs needed to bring up the RPi4 they are included > in above UEFi firmware (or the stuff used in other boot mechanisms). > I don't see how this is different from the "blobs" I load when I > boot my UEFI Asus mainboard. Correct, that is no different, but still suboptimal and can be replaced with libre software (for eg coreboot) on some machines. > > some Linux kernel patches are not in mainline etc > > What patches do you mean? WRT the Linux kernel, mainline always means kernel.org. > the RPi4b runs fine without anything but a stock debian kernel That may be true, but there are apparently patches being maintained by RPi that aren't being mainlined, I don't know the details though. > With "WIP libre replacement" do you mean the tianocore/EDK2/UEFi port > here? Sorry, I misremembered where it was mentioned and it turns out to be another thread on another list: https://lists.debian.org/debian-devel/2021/06/msg00043.html I mean rpi-open-firmware: https://github.com/librerpi/rpi-open-firmware/ https://github.com/itszor/vc4-toolchain https://github.com/itszor/vc4-toolchain/issues/7 BTW, the RPi4 boot process even has some DRM in it, but that is apparently easy to bypass due to bugs in boot code: https://github.com/librerpi/rpi-open-firmware/blob/master/docs/cracking-rpi4-hmac.txt > https://github.com/pftf/RPi4 Will this be added to edk2-platforms? https://github.com/tianocore/edk2-platforms/ -- bye, pabs https://wiki.debian.org/PaulWise
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