Going all the way back to early 2024, Intel Linux engineers have been working on supporting an Adaptive Sharpening Filter new to Lunar Lake. While Lunar Lake later launched in September 2024, the Linux patches for this feature remained under review and discussion. Besides the Intel driver implementation itself for Lunar Lake and newer, it also ushers in a new DRM sharpness property to help standardize such functionality for user-space that could be used by other kernel graphics drivers. Finally with the upcoming Linux 6.19 kernel, this Intel Content Adaptive Sharpness Filter “CASF” feature is being introduced to the mainline kernel.
Intel CASF is slated to be included in Linux 6.19 for what will be the first major kernel release of 2026 when it debuts around February. The Intel CASF enablement code was finally sent out today in the drm-next-pull request for queuing in DRM-Next for then merging next month into Linux Git for the v6.19 cycle.
Besides needing the updated Linux kernel driver code, Linux user-space needs to also the new DRM sharpness property. KDE Plasma 6.6 is introducing support for it as was recently added to KWin. Meanwhile there is this draft merge request still open for adding it to the GNOME Mutter compositor code. Hopefully that will be merged in time for GNOME 50 for making it into the likes of Ubuntu 26.04 LTS.
While this CASF support for Lunar Lake and newer is the most exciting change with today’s drm-intel-next pull request, there are also Variable Rate Refresh (VRR) updates included, enabling Xe3P LT PHY support, enabling frame-buffer compression (FBC) for Xe3P_LPD, and other code improvements and bug fixes. With the Intel Xe3 Panther Lake enablement squared away, lately Intel Linux graphics driver engineers have been increasing their focus on Xe3P enablement for Nova Lake processors as well as Crescent Island.
