> >> Hello Matthias, > >> > >> I have upgraded the Raspberry 3 firmware from raspi3-firmware > >> (1.20190215-1+deb10u4) to raspi-firmware (1.20200601-3) > >> [https://packages.debian.org/bullseye/raspi-firmware]. > >> > >> After the upgrade the output of U-Boot on the serial console is complete > >> gibberish as if the baudrate were incorrect. The output from the Linux > >> kernel is fine at 115200 baud. > > > > I've seen similar on all firmware since around mid April up until > > recently, it seems to be fixed with releases in Oct (I'm using one > > from Oct 8th), I'm not sure if it can be fixed in U-Boot but it seems > > to be due to a change in the firmware. > > Thanks for confirming the problem.
For reference I have found a number of other problems with recent firmwares and 2020.10 release: * U-Boot crashes on a RPi4 8Gb model if you don't have a display connected [1] * It doesn't boot, not sure if it's a crash or something else, you just get the rainbow screen, if you don't have the uart enabled in config.txt (ie just using a display for output). Both of these seem to be due to firmware changes as opposed to U-Boot changes, as it was working fine on the firmware from Apr 1st, but there's been various other issues there like the 8Gb model doesn't completely work. [1] https://lists.denx.de/pipermail/u-boot/2020-September/428156.html > Using the most current files from > https://github.com/raspberrypi/firmware does not solve the problem for me. > > In bcm283x_mu_serial_setbrg() we divide a clock rate by the baudrate. > divider = plat->clock / (baudrate * 8); > > If we do not have the correct clock rate, the actual baudrate will be wrong. > > Best regards > > Heinrich > > > > >> I observe this both with rpi_3_defconfig and rpi_arm64_defconfig, > >> v2020.10 and current origin/master. > >> > >> config.txt: > >> > >> arm_control=0x200 > >> enable_uart=1 > >> upstream_kernel=1 > >> kernel=u-boot.bin > >> > >> boot.scr: > >> setenv autoload no > >> dhcp > >> load mmc 0:1 $fdt_addr_r bcm2710-rpi-3-b-plus.dtb > >> load mmc 0:2 $kernel_addr_r EFI/debian/grubaa64.efi > >> bootefi $kernel_addr_r $fdt_addr_r > >> > >> Best regards > >> > >> Heinrich >
