PowerPC 601 Support Being Retired In Linux 5.10 - The First 32-bit PowerPC CPU
The PowerPC 601 was designed in the early 90's as the first processor supporting 32-bit PowerPC. The PowerPC 601 was a legendary processor for its time in the PowerPC world for introducing SMP capabilities and other new features of the era while being designed for the IBM RS/6000. But now nearly three decades after PowerPC 601 processors first hit the market, Linux is removing the kernel support.
In code set to be merged as part of the POWER changes for Linux 5.10, PowerPC 601 support is being dropped as it's no longer in use by any kernel default configuration (defconfig). The PowerPC 601 code also requires special handling from the rest of the PowerPC 6xx support still within the kernel, thus it's a maintenance burden.
The change removing the PowerPC 601 support by Christophe Leroy ends with, "Retire it." The rest of the 6xx series and other early PowerPC 32-bit CPU support remains from Freescale and IBM with the pending Linux 5.10 changes.
After removing the PowerPC 601 code, there were other immediate follow-up changes beginning to clean-up the PowerPC code further now that the 601 doesn't need to be supported.