This doesn't look right for how it's coded.  This would be the
CONFIG_4xx || CONFIG_BOOKE case, but CONFIG_4xx includes PowerPC 405.
That has a different bit layout among the DBCR registers.  Namely, on
405 you would be clearing the TDE and IAC1 events because the DAC
events are in DBCR1, not DBCR0.

Maybe guarding the 405-specific parts in a separate "#if
defined(CONFIG_40x)" block will do?

Do you think it's worth to support this facility on 405's processors? If
so, i'll gladly work on a solution to it.

Regards,
Luis