将 RaspberryPi 从 19.10 升级到 20.04 后升级成功但启动失败

Question

我有一台安装了 Ubuntu 19.10 arm64 的 Raspberry Pi (3)。我成功地通过升级到 20.04，do-release-upgrade然后重新启动。什么都没有。它没有通过彩虹图形。然而，这不是 20.04 的问题，因为如果我将 20.04 映像刷入卡中，就不会出现问题。升级可能有什么问题？

Answer 1

答案是 Ubuntu OS 安装程序不会更新（分区）config.txt中的文件- 该文件在发布之间会更新，但显然在升级期间安装程序不会更新（尽管 OS 需要它）。这意味着升级后，它不再有效，系统无法启动。/boot/firmwaresystem-boot

20.04 版本如下所示：

# Please DO NOT modify this file; if you need to modify the boot config, the
# "usercfg.txt" file is the place to include user changes. Please refer to
# the README file for a description of the various configuration files on
# the boot partition.

# The unusual ordering below is deliberate; older firmwares (in particular the
# version initially shipped with bionic) don't understand the conditional
# [sections] below and simply ignore them. The Pi4 doesn't boot at all with
# firmwares this old so it's safe to place at the top. Of the Pi2 and Pi3, the
# Pi3 uboot happens to work happily on the Pi2, so it needs to go at the bottom
# to support old firmwares.

[pi4]
kernel=uboot_rpi_4.bin
max_framebuffers=2

[pi2]
kernel=uboot_rpi_2.bin

[pi3]
kernel=uboot_rpi_3.bin

[all]
arm_64bit=1
device_tree_address=0x03000000

# The following settings are "defaults" expected to be overridden by the
# included configuration. The only reason they are included is, again, to
# support old firmwares which don't understand the "include" command.

enable_uart=1
cmdline=nobtcmd.txt

include syscfg.txt
include usercfg.txt

显然，这需要更新后你更新了操作系统，但是前重新启动。如果不重新启动，您可以随时使用 SD 卡手动执行此操作，它仍能正常工作。