L310_PREFETCH_CTRL_OFFSET_MASK
val &= ~L310_PREFETCH_CTRL_OFFSET_MASK;
prefetch &= ~L310_PREFETCH_CTRL_OFFSET_MASK;
prefetch |= val & L310_PREFETCH_CTRL_OFFSET_MASK;
1 + (prefetch & L310_PREFETCH_CTRL_OFFSET_MASK));