Hi guys, First of all, thank you for all your reviews. I hope I can answer all your questions here. If I forget something please let me know.
I don't have much experience with arm/arm64 and I don't have previous experience with u-boot and contributing to it. So please guide me for next steps. Also I don't think it makes sense to expect all devices or any device may/should work after initial boot support. I would suggest going with small steps and talking about gfx/usb/net/mmc in dedicated patchsets after initial support is being merged. > Could this be the title for the patch, "initial support" is fine for > the cover letter, but doesn't really out line what this specific patch > actually does. Can confirm. My bad. Will fix it in the next patchset. >> includes: >> * 1GB of RAM (from 4GB or 8GB total) >> * VPU memory interface >> * SOC range (main peripherals) > Could you include details where this information came from as well please? By looking into FDT for memory, framebuffer, and soc nodes. I can add this info in v3. > When you say it doesn't work, does it just not output display or does > the device lock up and you need to disable it? There are artifacts on the screen and the system locks up. > For the rpi4 it was as simple as adding a new compatible [1] for the > rev6 of the IP block as for the bits that we use in U-Boot nothing > changed, but the kernel changes for the rev7 that's in the RPi5 needed > updating registers [2] so I'm not sure if we're going to need to do > more for this or not. I've tried it by playing with "simple-fb" and with "bcm2712-hdmi0". And no luck. Still visible artifacts on the screen. I see valid debug output from bcm2835_video_probe() so the mailbox for set/get base/resolution/pitch/stride works. But still observe the same issue with artifacts and lock up. FYI by default the probing starts due to "bcm2708-fb". > Might be worth looking to see if there's changes in the kernel for > this. In an initial look I didn't see any changes to their kernel > here. I don't see any changes either. I'm not able to find any official confirmation. But most of 'tags' work except two or three. And all of them have response code 0x8000_0001. And FDT contains new info compared to old versions (for these tags). Which leads to the conclusion they are deprecated. > We probably need a patch to the identifier too similar to the following: > https://source.denx.de/u-boot/u-boot/-/commit/5e7e6619c85c090f6b62685a9d90f748f1729d12 Honestly I didn't get the reason/goal besides old/new scheme except there is a final print: > printf("RPI %s (0x%x)\n", model->name, revision); which is kind of simular to my: > printf("FW FDT model : %s\n", fdt_model); Besides parsing the "Raspberry Pi 5 Model B Rev 1.0" string to get revision from it? Format is unknown and nobody knows what will be changed. Will it be "Raspberry Pi 5 Model B Rev 1.0a" or Raspberry Pi 5 Model B Rev 1.01"? I don't know. If it's really needed then I would suggest parsing OTP to get precise info with known format. P.S.: Please let me know if I answered all the questions so I can send v3. Regards, Dmitry