Intel Icelake Thunderbolt Support Not Coming Until Linux 5.4

While the Linux support around Intel Icelake is largely settled, one area that has gone under the radar until now has been the Thunderbolt support, which now is available in patch form but won't be mainlined until Linux 5.4.

With Icelake, Intel moved the Thunderbolt controller onto the CPU itself (sans the Thunderbolt power delivery circuitry). Overnight the Linux support for this Icelake Thunderbolt support was published by Intel employee and Linux Thunderbolt code maintainer Mika Westerberg.

With the patches there is some 500 lines of new code for enabling this latest Intel controller. In the patches Mika also points out with the Icelake controller there are no Thunderbolt security levels built-in so DMA protections are being handled by an IOMMU.

While the Linux 5.3 merge window is opening up soon, due to these patches only now being published and Mika going on holiday the next month, this support is being held off until the Linux 5.4 cycle later in the year. At least the rest of the Intel Icelake CPU and Gen11 graphics support is already in quite good shape with the mainline kernel.