Intel HD Graphics (Braswell (Valleyview Cherryview)) no hardware acceleration after drm-510-kmod

[grandpa]

Hello,

Hardware acceleration for Intel HD Graphics Valleyview and Cherryview works up to 14.1-RELEASE with drm-510-kmod.

Higher versions works but the hardware acceleration is not working.

Drm-510-kmod is barely alive in the ports tree for 2026Q2 - it will most likely be gone in Q3.

Compiling from source or installing xf86-video-intel, libva, libvdpau does not enable hardware acceleration.

A PR has been posted - 295788 - but the bug description is very vague.

The process to port a new version of drm drivers for FreeBSD is to grab the Linux drm, change as little as possible until it runs on FreeBSD.

Looking at the source code for all drm-kmod versions the code for Valleyview and Cherryview is still there (515, 61, 66, latest).

Let's assume that this bug comes from FreeBSD going from 14.1 to 14.2 or from the drm going from 510 to 515.

In the Makefile for drm-510-kmod it says "Not supported on FreeBSD 14.2 and higher" but it does not say why.

Does anyone know why drm-510-kmod not is supported on >14.2? ​

​

/grandpa

 

[grandpa]

Hacking around with code shows that it is possible to squeeze drm-510-kmod through the compiler on 15-RELEASE-p9 but this is of course futile since the leap is too big from 14.1 to 15.0-p9 (or drm-51 to 66). With some changes to drm_os_freebsd.c, drm_pci.c, drm_sysctl_freebsd.c, i915_gem_mman.c and a reboot an upside down green plasma login screen can be seen before the GPU_HANG comes.

Probably better to compare drm-510 to drm-515 and try to understand what has changed?

/grandpa