Raspberry Pi Install Guide/Pi5
Bluetooth
The file /lib/firmware/brcm/BCM4345C0.hcd is not in linux-firmware at the time of writing.
Real Time Clock
The Pi5 has a battery backed real time clock. The battery is an optional extra. When the battery is fitted, the hwclock service can be used in place of swclock.
The RTC can be used for alarms, wakeups without a backup battery, provided the Pi is always powered, to keep the clock alive.
Batteries are available in two types. Rechargeable and non-recharagable, like most PC motherboard CMOS batteries.
Battery charging is disabled by default, which is safe as attempting to recharge a non-recharagable lithium battery is both dangerous and bad for the battery lifetime.
Users who are sure that they have a rechargeable battery need to follow enabling trickle charging to turn on the battery charger. Heed the warning there too.
Serial Output on GPIO 14 and 15
By default the serial output for the RPI5 goes to the dedicated serial header on the board instead of the GPIO pins. You can re-enable the output on GPIO 14/15 by adding in the following code into the config.txt file.
dtparam=uart0 # Enable UART0/ttyAMA0 on GPIO 14 & 15
dtparam=uart0_console # Enable UART0/ttyAMA0 on GPIO 14 & 15 and make it the console UART
Wifi
The file brcmfmac43455-sdio.txt is required in /lib/firmware/brcm/ before the wifi interface will appear in
user $
ip link
At the time of writing it was not included in linux-firmware.
Xorg on Pi5
The automatic setup fails on a Pi 5. The following xorg.conf fragment is required.
# Shamelessly copied from PiOS
Section "OutputClass"
Identifier "vc4"
MatchDriver "vc4"
Driver "modesetting"
Option "PrimaryGPU" "true"
EndSection