IOC_PCOM
writeq(info->gart_base | ilog2(info->gart_size), info->ioc_regs+IOC_PCOM);
readq(info->ioc_regs+IOC_PCOM); /* flush */
WRITE_REG(ioc->ibase | 31, ioc->ioc_hpa + IOC_PCOM);
WRITE_REG(0 | 31, ioc->ioc_hpa+IOC_PCOM);
WRITE_REG( SBA_IOVA(ioc, iovp, 0, 0), ioc->ioc_hpa+IOC_PCOM);
READ_REG(ioc->ioc_hpa+IOC_PCOM); /* flush purges */
READ_REG(ioc->ioc_hpa+IOC_PCOM); /* flush purges */