[Solved] External monitor woes on USBC-Displayport adapter

kjozsa · 2026-02-13 20:22:51

I have a HP Zbook Firefly G11 laptop with 2 usb-c / thunderbird ports and an integrated Intel gpu (Intel Corporation Meteor Lake-P [Intel Arc Graphics] (rev 08)). I connected a Dell external monitor using a 8k-capable USB-C -> DisplayPort 1.4 cable, but I have no luck getting signal to the monitor. I'm using the XE driver with Wayland and GNOME. Connecting the same monitor on HDMI works, but this laptop only has HDMI 2.0b, so no 4k@120Hz - hence my attempt to wire it on displayport instead.

The most obvious issue is that no matter what I try:

~ $ ls -la  /sys/class/typec/
~ $

Kernel options are tried, in various combinations, from switching only XE on to trying various switches alone, or together:

options root=/dev/vg0/root rw xe.enable=1 xe.force_probe=7d55 i915.force_probe=!7d55 xe.enable_psr=0 xe.enable_dc=0 xe.enable_fbc=0 ipv6.disable=1 usb4.usb4=1 xe.display_clk=2300000 drm.vblankoffdelay=1 usbhid.force=1 xe.force_probe=46a xe.runpm=0 i915.enable_ucsi=1 ucsi_acpi.default_bridge=1 usb4.earlycr_en=1 thunderbolt.force_power=1 xe.tbt_compat=1

Related kernel modules loaded:

~ $ lsmod | grep -E "typec|ucsi|usb4|thunderbolt"
ucsi_acpi              12288  0
typec_ucsi             77824  1 ucsi_acpi
typec                 114688  1 typec_ucsi
roles                  16384  1 typec_ucsi
thunderbolt           577536  1 typec
~ $

I also tried to dig around in the BIOS, but not many options there. There is nothing USB4-related, nor anything about Thunderbird security (I saw recommendations disabling those). There is a "Thunderbolt mode" setting which can be on/off, I tried both modes (though On seems to be the trivial choice).

No matter what I tried so far, both `/sys/class/typec/` and `boltctl list` remains completely empty, by default and after hotplug events as well.

Any hints how to get my typec port running? Could this be a hardware issue with this 2y old ZBook? I have no other OS to try, so I'm not sure really.. Thanks.

Last edited by kjozsa (2026-02-17 11:25:38)

kjozsa · 2026-02-13 21:10:38

I gave it an extended session of debugging this issue with Claude Opus. Here is its summary:

Update: Root cause identified via kprobe tracing

After extensive debugging I found the exact failure path. The ucsi_acpi driver does probe the USBC000:00 device, and the ACPI _DSM calls succeed. The probe fails because the UCSI version in the shared memory region is 0x0000.

Here's the trace:

ucsi_acpi_probe() is called
  → platform_get_resource(IORESOURCE_MEM) succeeds (memory at 0x61E27000)
  → acpi_install_notify_handler() succeeds
  → ucsi_register()
    → read_version() → ucsi_acpi_dsm(READ) succeeds
    → version == 0x0000 → returns -ENODEV
The UCSI spec requires the Platform Policy Manager (PPM) — in this case the HP Embedded Controller firmware — to populate the UCSI data structure in shared memory, including the version field (e.g. 0x0200 for UCSI 2.0). The EC on this machine never does that, so the kernel correctly refuses to register the interface.

This is an HP EC firmware issue, not a kernel bug. Confirmed identical behavior on kernel 6.12.70-lts and 6.18.9.

Machine details:

HP ZBook Firefly 16 inch G11 Mobile Workstation PC
BIOS: W70 Ver. 01.08.01 (2025-12-10)
Intel Meteor Lake-P [Intel Arc Graphics] (7d55)
Thunderbolt 4 NHI controllers visible on PCI and bound to the thunderbolt driver
ACPI SSDT tables (UcsiAcpi, UcsiCntr) are present and well-formed
Things that won't help (saving others the time):

Switching between xe and i915 drivers — the issue is in the USB Type-C subsystem, not the GPU driver
Kernel parameters like thunderbolt.force_power, xe.tbt_compat, xe.runpm, i915.enable_ucsi — these don't exist
Switching kernel versions — tested 6.12 LTS and 6.18, same result
ACPI/SSDT overrides — the tables are correct, the EC just isn't initializing the shared memory
What might help:

HP BIOS/EC firmware update (if a newer one becomes available)

Sounds reasonable for me, but don't see much hope on simply waiting for a new firmware release..

Lone_Wolf · 2026-02-14 11:41:43

That would be the hp-zbook-firefly-16-inch-g11-mobile-workstation-pc ?

The specs I can find don't clarify whether those are actual thunderbolt ports or USB-C ports with alternate DP mode .

If the first is true, that chatbot may be right.
If the latter is true, the probe part may be irrelevant .

Not sure how to verify that, but let's start with getting some details of the laptop hardware.

please post the output of

$ lspci -k
$ lsusb -tv

kjozsa · 2026-02-14 11:56:11

Yes, exactly that hardware.

~ $ lspci -k
00:00.0 Host bridge: Intel Corporation Meteor Lake-H 6p+8e cores Host Bridge/DRAM Controller (rev 04)
	Subsystem: Hewlett-Packard Company Device 8cd1
	Kernel driver in use: igen6_edac
	Kernel modules: igen6_edac
00:02.0 VGA compatible controller: Intel Corporation Meteor Lake-P [Intel Arc Graphics] (rev 08)
	DeviceName: Onboard IGD
	Subsystem: Hewlett-Packard Company Device 8cd1
	Kernel driver in use: xe
	Kernel modules: i915, xe
00:04.0 Signal processing controller: Intel Corporation Meteor Lake-P Dynamic Tuning Technology (rev 04)
	Subsystem: Hewlett-Packard Company Device 8cd1
	Kernel driver in use: proc_thermal_pci
	Kernel modules: processor_thermal_device_pci
00:06.0 PCI bridge: Intel Corporation Arrow Lake-H/U PCIe Root Port #11 (PXPE) (rev 10)
	Subsystem: Hewlett-Packard Company Device 8cd1
	Kernel driver in use: pcieport
	Kernel modules: shpchp
00:07.0 PCI bridge: Intel Corporation Meteor Lake-P Thunderbolt 4 PCI Express Root Port #0 (rev 02)
	Subsystem: Hewlett-Packard Company Device 8cd1
	Kernel driver in use: pcieport
	Kernel modules: shpchp
00:07.2 PCI bridge: Intel Corporation Meteor Lake-P Thunderbolt 4 PCI Express Root Port #2 (rev 02)
	Subsystem: Hewlett-Packard Company Device 8cd1
	Kernel driver in use: pcieport
	Kernel modules: shpchp
00:08.0 System peripheral: Intel Corporation Meteor Lake-P Gaussian & Neural-Network Accelerator (rev 20)
	Subsystem: Hewlett-Packard Company Device 8cd1
00:0a.0 Signal processing controller: Intel Corporation Meteor Lake-P Platform Monitoring Technology (rev 01)
	Subsystem: Hewlett-Packard Company Device 8cd1
	Kernel driver in use: intel_vsec
	Kernel modules: intel_vsec
00:0b.0 Processing accelerators: Intel Corporation Meteor Lake NPU (rev 04)
	Subsystem: Hewlett-Packard Company Device 8cd1
	Kernel driver in use: intel_vpu
	Kernel modules: intel_vpu
00:0d.0 USB controller: Intel Corporation Meteor Lake-P Thunderbolt 4 USB Controller (rev 02)
	Subsystem: Hewlett-Packard Company Device 8cd1
	Kernel driver in use: xhci_hcd
	Kernel modules: xhci_pci
00:0d.2 USB controller: Intel Corporation Meteor Lake-P Thunderbolt 4 NHI #0 (rev 02)
	Subsystem: Hewlett-Packard Company Device 8cd1
	Kernel driver in use: thunderbolt
	Kernel modules: thunderbolt
00:0d.3 USB controller: Intel Corporation Meteor Lake-P Thunderbolt 4 NHI #1 (rev 02)
	Subsystem: Hewlett-Packard Company Device 8cd1
	Kernel driver in use: thunderbolt
	Kernel modules: thunderbolt
00:12.0 Serial controller: Intel Corporation Meteor Lake-P Integrated Sensor Hub (rev 20)
	Subsystem: Hewlett-Packard Company Device 8cd1
	Kernel driver in use: intel_ish_ipc
	Kernel modules: intel_ish_ipc
00:14.0 USB controller: Intel Corporation Meteor Lake-P USB 3.2 Gen 2x1 xHCI Host Controller (rev 20)
	Subsystem: Hewlett-Packard Company Device 8cd1
	Kernel driver in use: xhci_hcd
	Kernel modules: xhci_pci
00:14.2 RAM memory: Intel Corporation Meteor Lake-H/U Shared SRAM (rev 20)
	Subsystem: Hewlett-Packard Company Device 8cd1
	Kernel driver in use: intel_pmc_ssram_telemetry
	Kernel modules: intel_pmc_ssram_telemetry
00:14.3 Network controller: Intel Corporation Meteor Lake PCH CNVi WiFi (rev 20)
	Subsystem: Intel Corporation Wi-Fi 6E AX211 160MHz
	Kernel driver in use: iwlwifi
	Kernel modules: iwlwifi
00:15.0 Serial bus controller: Intel Corporation Meteor Lake-P Serial IO I2C Controller #0 (rev 20)
	Subsystem: Hewlett-Packard Company Device 8cd1
	Kernel driver in use: intel-lpss
	Kernel modules: intel_lpss_pci
00:16.0 Communication controller: Intel Corporation Meteor Lake-P CSME HECI #1 (rev 20)
	Subsystem: Hewlett-Packard Company Device 8cd1
	Kernel driver in use: mei_me
	Kernel modules: mei_me
00:1e.0 Communication controller: Intel Corporation Meteor Lake-P Serial IO UART Controller #0 (rev 20)
	Subsystem: Hewlett-Packard Company Device 8cd1
	Kernel driver in use: intel-lpss
	Kernel modules: intel_lpss_pci
00:1e.2 Serial bus controller: Intel Corporation Meteor Lake-P Serial IO SPI Controller #0 (rev 20)
	Subsystem: Hewlett-Packard Company Device 8cd1
	Kernel driver in use: intel-lpss
	Kernel modules: intel_lpss_pci
00:1f.0 ISA bridge: Intel Corporation Meteor Lake-H eSPI Controller (rev 20)
	Subsystem: Hewlett-Packard Company Device 8cd1
00:1f.3 Multimedia audio controller: Intel Corporation Meteor Lake-P HD Audio Controller (rev 20)
	Subsystem: Hewlett-Packard Company Device 8cd1
	Kernel driver in use: sof-audio-pci-intel-mtl
	Kernel modules: snd_sof_pci_intel_mtl, snd_hda_intel
00:1f.4 SMBus: Intel Corporation Meteor Lake-P SMBus Controller (rev 20)
	Subsystem: Hewlett-Packard Company Device 8cd1
	Kernel driver in use: i801_smbus
	Kernel modules: i2c_i801
00:1f.5 Serial bus controller: Intel Corporation Meteor Lake-P SPI Controller (rev 20)
	Subsystem: Hewlett-Packard Company Device 8cd1
	Kernel driver in use: intel-spi
	Kernel modules: spi_intel_pci
01:00.0 Non-Volatile memory controller: KIOXIA Corporation NVMe SSD Controller XG8 (rev 01)
	Subsystem: KIOXIA Corporation Device 0001
	Kernel driver in use: nvme
	Kernel modules: nvme

~ $ lsusb -tv
/:  Bus 001.Port 001: Dev 001, Class=root_hub, Driver=xhci_hcd/1p, 480M
    ID 1d6b:0002 Linux Foundation 2.0 root hub
/:  Bus 002.Port 001: Dev 001, Class=root_hub, Driver=xhci_hcd/4p, 20000M/x2
    ID 1d6b:0003 Linux Foundation 3.0 root hub
/:  Bus 003.Port 001: Dev 001, Class=root_hub, Driver=xhci_hcd/12p, 480M
    ID 1d6b:0002 Linux Foundation 2.0 root hub
    |__ Port 005: Dev 002, If 0, Class=Video, Driver=uvcvideo, 480M
        ID 04f2:b7e9 Chicony Electronics Co., Ltd 
    |__ Port 005: Dev 002, If 1, Class=Video, Driver=uvcvideo, 480M
        ID 04f2:b7e9 Chicony Electronics Co., Ltd 
    |__ Port 005: Dev 002, If 2, Class=Video, Driver=uvcvideo, 480M
        ID 04f2:b7e9 Chicony Electronics Co., Ltd 
    |__ Port 005: Dev 002, If 3, Class=Video, Driver=uvcvideo, 480M
        ID 04f2:b7e9 Chicony Electronics Co., Ltd 
    |__ Port 005: Dev 002, If 4, Class=Application Specific Interface, Driver=[none], 480M
        ID 04f2:b7e9 Chicony Electronics Co., Ltd 
    |__ Port 006: Dev 003, If 0, Class=Human Interface Device, Driver=usbhid, 12M
        ID 3434:0d13  
    |__ Port 006: Dev 003, If 1, Class=Human Interface Device, Driver=usbhid, 12M
        ID 3434:0d13  
    |__ Port 006: Dev 003, If 2, Class=Human Interface Device, Driver=usbhid, 12M
        ID 3434:0d13  
    |__ Port 009: Dev 004, If 0, Class=Human Interface Device, Driver=usbhid, 12M
        ID 046d:c52b Logitech, Inc. Unifying Receiver
    |__ Port 009: Dev 004, If 1, Class=Human Interface Device, Driver=usbhid, 12M
        ID 046d:c52b Logitech, Inc. Unifying Receiver
    |__ Port 009: Dev 004, If 2, Class=Human Interface Device, Driver=usbhid, 12M
        ID 046d:c52b Logitech, Inc. Unifying Receiver
    |__ Port 010: Dev 005, If 0, Class=Wireless, Driver=btusb, 12M
        ID 8087:0033 Intel Corp. AX211 Bluetooth
    |__ Port 010: Dev 005, If 1, Class=Wireless, Driver=btusb, 12M
        ID 8087:0033 Intel Corp. AX211 Bluetooth
/:  Bus 004.Port 001: Dev 001, Class=root_hub, Driver=xhci_hcd/2p, 20000M/x2
    ID 1d6b:0003 Linux Foundation 3.0 root hub
~ $

Lone_Wolf · 2026-02-15 12:57:34

00:0d.3 USB controller: Intel Corporation Meteor Lake-P Thunderbolt 4 NHI #1 (rev 02)
	Subsystem: Hewlett-Packard Company Device 8cd1
	Kernel driver in use: thunderbolt
	Kernel modules: thunderbolt

So there is a thunderbolt controller present .

From Intel meteor lake capabilities

Supported on Type-C or Native connector (Fixed DP up to HBR3 link rate)

The max bandwitdh for HBR3 (High Bit Rate 3) is 32.40 Gbit/s which is sufficient for 3840x2160 x 120 .
Is that the resolution you want to use ?

kjozsa · 2026-02-15 13:55:20

Yes, I'm aiming to use that, 3840x2160 @ 120Hz.

At this moment I'm less worried about the bandwidth, and more worried on `/sys/class/typec/` remaining completely empty, with no kernel event in dmesg or journalctl, when I plug in this TypeC-Displayport cable.

Lone_Wolf · 2026-02-15 14:58:13

https://support.hp.com/us-en/drivers/hp … 2101990486 shows the latest firmware was released on jan 7 2026 .

Are you using that version ?

kjozsa · 2026-02-15 20:18:52

Yes, I'm on the latest BIOS package.

$ sudo dmidecode -s bios-version
W70 Ver. 01.08.01

$ sudo fwupdmgr get-updates
Devices with no available firmware updates:
 • Internal SPI Controller (BIOS)
 • HP 5MP Camera
 • HP UEFI Secure Boot DB
 • HP UEFI Secure Boot KEK
 • KEK CA
 • KXG80ZNV512G KIOXIA
 • PCH SPI Controller
 • UEFI CA
 • UEFI Device Firmware
 • UEFI Device Firmware
 • Windows UEFI CA
Devices with the latest available firmware version:
 • System Firmware
 • UEFI dbx
 • Unifying Receiver
No updates available

Lone_Wolf · 2026-02-15 22:20:44

Got it, seems besides waiting for new firmware from hp that solves this there are 2 options left :

- disable thunderbolt and try to connect using USB-C Alternate Mode DP
- patch the kernel driver to add the needed stuff (would proably be through a quirk for this specific laptop?)

I kinda doubt the first will work, and the 2nd is way above my skill level. Maybe other forum users can help.

seth · 2026-02-15 23:14:11

usb-c / thunderbird ports … about Thunderbird security

What cable specifically?
Does it say "thunderbird 3/4/5 compatible"?

According there're two physical usb-c ports: https://www.hp.com/gb-en/shop/Html/Merc … 0x1285.jpg
When you run "dmesg -W" and plug it to either USB-C port, does that produce *any* output?

kjozsa · 2026-02-16 09:19:16

The cable I got is this one: https://www.equip-info.net/equipinfo_en … 3342207101. Now that we speak about it, it does mention working in DP Alt Mode explicitly - I'll try again to disable Thunderbolt in the BIOS then.

Patching and compiling a kernel is within my comfort zone, but I'm unsure what to patch it with @Lone_Wolf much appreciate your efforts of trying to help with this anyway.. as always.

seth · 2026-02-16 09:24:50

If the picture I posted is correct you don't have a fancy DP+ altmode icon next to either port so I'd not hold my breath - you'll likely need a thunderbird™ 3/4/5 comaptible cable - though check the device manual if it supports the DP altmode but there was just no budget to print another icon
(isn't it wonderful how the *universal* serial bus made you forget about all the plug format and compatibility issues…)

kjozsa · 2026-02-17 11:25:16

Err.. it all works now. I get 3840x2160 @ 120Hz and it's all smooth and happy. The reasons? I'm not sure I want to talk about it in length.. but this cable clearly needed a stronger push in the new monitor's back to actually plug it in....

Arch Linux

#1 2026-02-13 20:22:51

[Solved] External monitor woes on USBC-Displayport adapter

#2 2026-02-13 21:10:38

Re: [Solved] External monitor woes on USBC-Displayport adapter

#3 2026-02-14 11:41:43

Re: [Solved] External monitor woes on USBC-Displayport adapter

#4 2026-02-14 11:56:11

Re: [Solved] External monitor woes on USBC-Displayport adapter

#5 2026-02-15 12:57:34

Re: [Solved] External monitor woes on USBC-Displayport adapter

#6 2026-02-15 13:55:20

Re: [Solved] External monitor woes on USBC-Displayport adapter

#7 2026-02-15 14:58:13

Re: [Solved] External monitor woes on USBC-Displayport adapter

#8 2026-02-15 20:18:52

Re: [Solved] External monitor woes on USBC-Displayport adapter

#9 2026-02-15 22:20:44

Re: [Solved] External monitor woes on USBC-Displayport adapter

#10 2026-02-15 23:14:11

Re: [Solved] External monitor woes on USBC-Displayport adapter

#11 2026-02-16 09:19:16

Re: [Solved] External monitor woes on USBC-Displayport adapter

#12 2026-02-16 09:24:50

Re: [Solved] External monitor woes on USBC-Displayport adapter

#13 2026-02-17 11:25:16

Re: [Solved] External monitor woes on USBC-Displayport adapter

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