POWERPC_PMC_ENABLE
config &= ~POWERPC_PMC_ENABLE;
config &= ~POWERPC_PMC_ENABLE;
config |= POWERPC_PMC_ENABLE;
mmcr |= SPR_MMCR1_P8_PMCNSEL(ri, config & ~POWERPC_PMC_ENABLE);
config |= POWERPC_PMC_ENABLE;
config_mask = ~config & POWERPC_PMC_ENABLE;
config &= ~POWERPC_PMC_ENABLE;