• Greg Ungerer's avatar
    m68knommu: fix overwriting of bits in ColdFire V3 cache control · bdee0e79
    Greg Ungerer authored
    The Cache Control Register (CACR) of the ColdFire V3 has bits that
    control high level caching functions, and also enable/disable the use
    of the alternate stack pointer register (the EUSP bit) to provide
    separate supervisor and user stack pointer registers. The code as
    it is today will blindly clear the EUSP bit on cache actions like
    invalidation. So it is broken for this case - and that will result
    in failed booting (interrupt entry and exit processing will be
    completely hosed).
    
    This only affects ColdFire V3 parts that support the alternate stack
    register (like the 5329 for example) - generally speaking new parts do,
    older parts don't. It has no impact on ColdFire V3 parts with the single
    stack pointer, like the 5307 for example.
    
    Fix the cache bit defines used, so they maintain the EUSP bit when
    carrying out cache actions through the CACR register.
    Signed-off-by: default avatarGreg Ungerer <gerg@linux-m68k.org>
    bdee0e79
m53xxacr.h 3.6 KB