linux/Documentation/features/core/generic-idle-thread/arch-support.txt

#
# Feature name:          generic-idle-thread
#         Kconfig:       GENERIC_SMP_IDLE_THREAD
#         description:   arch makes use of the generic SMP idle thread facility
#
    -----------------------
    |         arch |status|
    -----------------------
    |       alpha: |  ok  |
    |         arc: |  ok  |
    |         arm: |  ok  |
    |       arm64: |  ok  |
    |        csky: |  ok  |
    |     hexagon: |  ok  |
    |   loongarch: |  ok  |
    |        m68k: | TODO |
    |  microblaze: | TODO |
    |        mips: |  ok  |
    |       nios2: | TODO |
    |    openrisc: |  ok  |
    |      parisc: |  ok  |
    |     powerpc: |  ok  |
    |       riscv: |  ok  |
    |        s390: |  ok  |
    |          sh: |  ok  |
    |       sparc: |  ok  |
    |          um: | TODO |
    |         x86: |  ok  |
    |      xtensa: |  ok  |
    -----------------------