ATA_PM
if (ch->hw.pm_read(dev, ATA_PM, 0, &pm_chipid)) {
if (ch->hw.pm_read(dev, ATA_PM, 1, &pm_revision)) {
if (ch->hw.pm_read(dev, ATA_PM, 2, &pm_ports)) {
u_int32_t signature = ch->hw.softreset(dev, ATA_PM);
if (port < ATA_PM) {
if (port < ATA_PM) {