AHCI_CMD_STATUS_ST
ASSERT(!(port_cmd_status & AHCI_CMD_STATUS_ST));
(AHCI_CMD_STATUS_ST |
port_cmd_status |= AHCI_CMD_STATUS_ST;
if (port_cmd_status & (AHCI_CMD_STATUS_ST | AHCI_CMD_STATUS_CR)) {
port_cmd_status &= ~AHCI_CMD_STATUS_ST;