CTXDESC_CD_0_ASID
FIELD_PREP(CTXDESC_CD_0_ASID, asid));
FIELD_PREP(CTXDESC_CD_0_ASID, cd->asid)
cd->data[0] &= ~cpu_to_le64(CTXDESC_CD_0_ASID);
FIELD_PREP(CTXDESC_CD_0_ASID, smmu_domain->cd.asid));