ID_AA64DFR0_BRPs_SHIFT
nbkpts = ID_AA64DFR0_BRPs_VAL(dfr0) >> ID_AA64DFR0_BRPs_SHIFT;
#define ID_AA64DFR0_BRPs_MASK (UL(0xf) << ID_AA64DFR0_BRPs_SHIFT)
((((x) >> ID_AA64DFR0_BRPs_SHIFT) & 0xf) + 1)