Raspberry Pi5 fan custom curve not working.

> Will Ubuntu guys ever update that file?

Now that you reported the issue, yes.

awesome,
new bcm2712-rpi-5-b.dtb completely fixes the problem.

Thanks!!!

Can you provide steps to reproduce/show the problem?

please try to customize the fan curve by editing the /boot/firmware/config.txt file
you can do it by adding something like this:

```
dtparam=fan_temp0=65000
dtparam=fan_temp0_hyst=2500
dtparam=fan_temp0_speed=75

dtparam=fan_temp1=70000
dtparam=fan_temp1_hyst=2500
dtparam=fan_temp1_speed=128

dtparam=fan_temp2=75000
dtparam=fan_temp2_hyst=2500
dtparam=fan_temp2_speed=192

dtparam=fan_temp3=80000
dtparam=fan_temp3_hyst=2500
dtparam=fan_temp3_speed=255
```

This tells the system to start the fan once the temp reaches 65°C not before,
at 70°C it increases the fan speed, at 75°C it increases it even more until 80°C when the fan spins at 100%.

This configuration is completely ignored with the current bcm2712-rpi-5-b.dtb file, you can see that the fan starts at 50°C and not at 65°C.

Now try to overwrite that file with this one:
https://github.com/raspberrypi/firmware/blob/master/boot/bcm2712-rpi-5-b.dtb
reboot the system and try again and boom, it now works as expected.

To stress the CPU and monitor the CPU temperature/Fan speed at the same time, you can use a tool like s-tui.
https://github.com/amanusk/s-tui

feel free to ask if you need further info :)
thanks
Davide

This bug is awaiting verification that the linux-raspi/6.5.0-1014.17 kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-mantic-linux-raspi' to 'verification-done-mantic-linux-raspi'. If the problem still exists, change the tag 'verification-needed-mantic-linux-raspi' to 'verification-failed-mantic-linux-raspi'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

Waving through.

This bug was fixed in the package linux-raspi - 6.5.0-1014.17

---------------
linux-raspi (6.5.0-1014.17) mantic; urgency=medium

  * mantic/linux-raspi: 6.5.0-1014.17 -proposed tracker (LP: #2055574)

  * Packaging resync (LP: #1786013)
    - [Packaging] drop ABI data
    - debian.raspi/dkms-versions -- update from kernel-versions (main/2024.03.04)

  * Raspberry Pi5 fan custom curve not working. (LP: #2054921)
    - ARM: dts: bcm2712-rpi-5-b: Add fan speed dtparams

  [ Ubuntu: 6.5.0-27.28 ]

  * mantic/linux: 6.5.0-27.28 -proposed tracker (LP: #2055584)
  * Packaging resync (LP: #1786013)
    - [Packaging] drop ABI data
    - [Packaging] update annotations scripts
    - debian.master/dkms-versions -- update from kernel-versions (main/2024.03.04)
  * CVE-2024-26597
    - net: qualcomm: rmnet: fix global oob in rmnet_policy
  * CVE-2024-26599
    - pwm: Fix out-of-bounds access in of_pwm_single_xlate()
  * Drop ABI checks from kernel build (LP: #2055686)
    - [Packaging] Remove in-tree abi checks
  * Cranky update-dkms-versions rollout (LP: #2055685)
    - [Packaging] remove update-dkms-versions
    - Move debian/dkms-versions to debian.master/dkms-versions
    - [Packaging] Replace debian/dkms-versions with $(DEBIAN)/dkms-versions
  * linux: please move erofs.ko (CONFIG_EROFS for EROFS support) from linux-
    modules-extra to linux-modules (LP: #2054809)
    - UBUNTU [Packaging]: Include erofs in linux-modules instead of linux-modules-
      extra
  * performance: Scheduler: ratelimit updating of load_avg (LP: #2053251)
    - sched/fair: Ratelimit update to tg->load_avg
  * IB peer memory feature regressed in 6.5 (LP: #2055082)
    - SAUCE: RDMA/core: Introduce peer memory interface
  * linux-tools-common: man page of usbip[d] is misplaced (LP: #2054094)
    - [Packaging] rules: Put usbip manpages in the correct directory
  * CVE-2024-23851
    - dm: limit the number of targets and parameter size area
  * CVE-2024-23850
    - btrfs: do not ASSERT() if the newly created subvolume already got read
  * x86: performance: tsc: Extend watchdog check exemption to 4-Sockets platform
    (LP: #2054699)
    - x86/tsc: Extend watchdog check exemption to 4-Sockets platform
  * linux: please move dmi-sysfs.ko (CONFIG_DMI_SYSFS for SMBIOS support) from
    linux-modules-extra to linux-modules (LP: #2045561)
    - [Packaging] Move dmi-sysfs.ko into linux-modules
  * Fix AMD brightness issue on AUO panel (LP: #2054773)
    - drm/amdgpu: make damage clips support configurable
  * Mantic update: upstream stable patchset 2024-02-28 (LP: #2055199)
    - f2fs: explicitly null-terminate the xattr list
    - pinctrl: lochnagar: Don't build on MIPS
    - ALSA: hda - Fix speaker and headset mic pin config for CHUWI CoreBook XPro
    - mptcp: fix uninit-value in mptcp_incoming_options
    - wifi: cfg80211: lock wiphy mutex for rfkill poll
    - wifi: avoid offset calculation on NULL pointer
    - wifi: mac80211: handle 320 MHz in ieee80211_ht_cap_ie_to_sta_ht_cap
    - debugfs: fix automount d_fsdata usage
    - nvme-core: fix a memory leak in nvme_ns_info_from_identify()
    - drm/amd/display: update dcn315 lpddr pstate latency
    - drm/amdgpu: Fix cat debugfs ...