Virtual m68k Machine Proves Capable, Xtensa & C-SKY Archs See Updates Too

The Motorola 68000, Xtensa, and C-SKY processor architectures all saw notable additions for the in-development Linux 5.19 kernel.

Notable with the m68k changes for Linux 5.19 is the introduction of a new machine target based on the Google Goldfish interfaces. Notable with the m68k changes for Linux 5.19 is the introduction of a new machine target based on the Google Goldfish interfaces. The popular Macintosh Quadra 800 target used for virtual machine purposes targeting m68k is limited to just 1GB of RAM and a specific set of interfaces to match that actual vintage hardware.

With the new m68k machine target, it's based on Google's Goldfish originally used for Android simulations. This new target allows virtual machines with up to 3.2GB of system memory and up to 128 VirtIO devices in this purely virtual m68k platform. QEMU 6.0 already merged its support and now for Linux 5.19 the kernel code is ready. The new virtual m68k machine support is behind the "VIRT" option for Motorola 68000 kernel builds.

This new target is the main change as part of the m68k updates sent in today for Linux 5.19.

The C-SKY based Xuantie C910 SoC.

Meanwhile C-SKY changes were submitted today for Linux 5.19. That Chinese domestic CPU architecture for IoT and other use-cases saw a few changes worth mentioning. C-SKY has added three atomic optimizations, memcpy and memcpy_io optimizations, and some code fixes.

The Xtensa CPU architecture for that Tensilica ISA that was acquired by Cadence already nearly a decade ago also saw some updates for this new kernel. The Xtensa updates include support for co-processors on SMP builds, support for the Kernel Concurrency Sanitizer (KCSAN), handling of protection faults in no-MMU configurations, suppoer for hibernation, support for using co-processors in the kernel mode, support for context tracking, and a variety of other improvements.