IXGBE_FEATURE_MSI
if (sc->feat_cap & IXGBE_FEATURE_MSI)
sc->feat_en |= IXGBE_FEATURE_MSI;
| IXGBE_FEATURE_MSI
(sc->feat_en & IXGBE_FEATURE_MSI) ? 1 : 0;
sc->feat_en &= ~IXGBE_FEATURE_MSI;
sc->feat_en &= ~IXGBE_FEATURE_MSI;
sc->feat_en |= IXGBE_FEATURE_MSI;