Public bug reported: Sorry if I'm reporting this against the wrong package.
The default `/boot/firmware/config.txt` file in `noble` server contains the directive `enable_uart=1` in a section for `[all]` Raspberry Pi versions. The documentation at https://www.raspberrypi.com/documentation/computers/config_txt.html#enable_uart says: `enable_uart=1` (in conjunction with `console=serial0,115200` in `cmdline.txt`) requests that the kernel creates a serial console, accessible using GPIOs 14 and 15 (pins 8 and 10 on the 40-pin header). Editing `cmdline.txt` to remove the line `quiet` enables boot messages from the kernel to also appear there. This makes sense for Ubuntu Server on the Raspberry Pi 4, but the Raspberry Pi 5 has a dedicated UART connector for the console that's not on the GPIO header. Up until now it appears that `enable_uart=1` actually did nothing on the Raspberry Pi 5, but as of EEPROM version 2025-02-12 this directive *does* move the console from the dedicated UART and `/dev/ttyAMA10` to the GPIO pins and `/dev/ttyAMA0`. So a problem arises if one is already using `/dev/ttyAMA0` on the GPIO pins for some reason and then upgrades the EEPROM. To work around this problem one can comment out `enable_uart=1` or add `enable_uart=0` to the bottom of `config.txt`. Ubuntu should consider moving `enable_uart=1` out of `[all]` so that it doesn't apply to the `[pi5]`. It probably should be applied to more than just the `[pi4]`, though. See also: https://github.com/raspberrypi/rpi-eeprom/issues/673 ** Affects: linux-raspi (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux-raspi in Ubuntu. https://bugs.launchpad.net/bugs/2101104 Title: Raspberry Pi 5 serial console device changes with EEPROM upgrade Status in linux-raspi package in Ubuntu: New Bug description: Sorry if I'm reporting this against the wrong package. The default `/boot/firmware/config.txt` file in `noble` server contains the directive `enable_uart=1` in a section for `[all]` Raspberry Pi versions. The documentation at https://www.raspberrypi.com/documentation/computers/config_txt.html#enable_uart says: `enable_uart=1` (in conjunction with `console=serial0,115200` in `cmdline.txt`) requests that the kernel creates a serial console, accessible using GPIOs 14 and 15 (pins 8 and 10 on the 40-pin header). Editing `cmdline.txt` to remove the line `quiet` enables boot messages from the kernel to also appear there. This makes sense for Ubuntu Server on the Raspberry Pi 4, but the Raspberry Pi 5 has a dedicated UART connector for the console that's not on the GPIO header. Up until now it appears that `enable_uart=1` actually did nothing on the Raspberry Pi 5, but as of EEPROM version 2025-02-12 this directive *does* move the console from the dedicated UART and `/dev/ttyAMA10` to the GPIO pins and `/dev/ttyAMA0`. So a problem arises if one is already using `/dev/ttyAMA0` on the GPIO pins for some reason and then upgrades the EEPROM. To work around this problem one can comment out `enable_uart=1` or add `enable_uart=0` to the bottom of `config.txt`. Ubuntu should consider moving `enable_uart=1` out of `[all]` so that it doesn't apply to the `[pi5]`. It probably should be applied to more than just the `[pi4]`, though. See also: https://github.com/raspberrypi/rpi-eeprom/issues/673 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-raspi/+bug/2101104/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
