[Bug 297014] HDMI does not expose 120/144 Hz modes and rejects manual modes (Intel, Meteor Lake)

https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D297014

            Bug ID: 297014
           Summary: HDMI does not expose 120/144 Hz modes and rejects
                    manual modes (Intel, Meteor Lake)
           Product: Base System
           Version: 15.1-RELEASE
          Hardware: amd64
                OS: Any
            Status: New
          Severity: Affects Some People
          Priority: ---
         Component: standards
          Assignee: [email protected]
          Reporter: [email protected]

***AI was used to help organize and format this report. All commands were r=
un
and verified on the affected system.***

# Intel Meteor Lake HDMI limited to 60 Hz on ThinkPad T16 Gen 3

## System

* **FreeBSD:** 15.1-RELEASE
* **Kernel:** GENERIC (releng/15.1-n283562-96841ea08dcf)
* **DRM:** `drm-latest-kmod-6.9.1501000_1` (latest package available for
FreeBSD 15.1)

## Hardware

* Lenovo ThinkPad T16 Gen 3
* Intel Core Ultra 7 155u (Meteor Lake)
* Lenovo G25-10 (1920=C3=971080 144 Hz)
* Connected using the laptop's built-in HDMI port

## Problem

The external monitor is limited to **60 Hz** under FreeBSD.

The monitor supports **120 Hz** and **144 Hz**, and the exact same laptop,
monitor, HDMI cable, and HDMI port work correctly at **1920=C3=971080@144 H=
z** under
Artix Linux.

## Firmware

Initially, the Intel GPU firmware was missing.

`dmesg` reported:

```text
Failed to load DMC firmware
Failed to load GuC firmware
Run pkg install gpu-firmware-kmod
```

After installing `gpu-firmware-kmod`, the firmware loads correctly:

```text
successfully loaded firmware image 'i915/mtl_dmc.bin'
Finished loading DMC firmware
successfully loaded firmware image 'i915/mtl_guc_70.bin'
successfully loaded firmware image 'i915/mtl_huc_gsc.bin'
GT0: GUC: submission enabled
GT0: GUC: SLPC enabled
GT0: GUC: RC enabled
```

The refresh-rate issue remains after the firmware is installed.

## xrandr

Only 60 Hz modes are available:

```text
HDMI-1 connected

1920x1080 60.00*
1920x1080 59.94
1920x1080 50.00
```

No 120 Hz or 144 Hz modes are listed.

## Xorg

Xorg successfully reads the monitor's EDID and reports the high refresh rate
timings:

```text
Printing DDC gathered Modelines:

1920x1080 333.07 MHz
1920 1944 1976 2056
1080 1083 1088 1125

1920x1080 285.50 MHz
1920 1968 2000 2080
1080 1083 1088 1144
```

The monitor capabilities are also detected correctly:

```text
Vertical refresh: 48=E2=80=93144 Hz
Maximum pixel clock: 345 MHz
```

This suggests that the EDID is being read correctly.

## drm_info

`drm_info` correctly detects the HDMI connector and monitor:

```text
Connector: HDMI-A
Status: connected

Monitor:
Lenovo G25-10
```

However, the DRM connector only reports:

```text
1920x1080@60
[email protected]
1920x1080@50
...
```

The 120 Hz and 144 Hz modes present in the EDID are missing from the
connector's exported mode list.

## Manual mode test

Using the exact 144 Hz timing reported by Xorg:

```sh
xrandr --newmode "1920x1080_144" \
333.07 1920 1944 1976 2056 \
1080 1083 1088 1125 +HSync -VSync

xrandr --addmode HDMI-1 "1920x1080_144"

xrandr --output HDMI-1 --mode "1920x1080_144"
```

Result:

```text
xrandr: Configure crtc 1 failed
```

The same result occurs when using the 120 Hz timing from the EDID.

## Expected behavior

The monitor advertises 120 Hz and 144 Hz support.

These modes should be available through DRM/KMS and selectable with `xrandr=
`.

## Actual behavior

* Xorg successfully reads the EDID.
* Xorg detects the monitor's 120 Hz and 144 Hz timings.
* DRM only exposes 60 Hz modes.
* Manually adding the EDID timings succeeds, but attempting to activate them
fails with:

```text
xrandr: Configure crtc 1 failed
```

## Summary

Observed behavior:

* =E2=9C=93 Intel GPU firmware loads successfully.
* =E2=9C=93 HDMI monitor is detected correctly.
* =E2=9C=93 EDID is read successfully.
* =E2=9C=93 Xorg detects the monitor's 120 Hz and 144 Hz timings.
* =E2=9C=97 DRM only exposes 60 Hz modes.
* =E2=9C=97 Attempting to use the EDID's 120 Hz or 144 Hz timings fails wit=
h `Configure
crtc 1 failed`.

Because the same hardware works at 144 Hz under Linux, this appears to be
specific to the current FreeBSD Intel DRM/KMS implementation for Meteor Lake
over HDMI.



Hardware probe (if relevant)

https://bsd-hardware.info/?probe=3D5697f8b00b



Thanks!

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