Pretty much what it says on the tin. Examples:
bhnd0: <BCM4312 SIBA bus> on bhndb0 bhnd0: <BCM43225 BCMA bus> on bhndb0 bhnd0: <BCM4716 BCMA bus> at mem 0x18000000-0x180fffff on nexus0 bhnd0: <BCM5365 SIBA bus> at mem 0x18000000-0x180fffff on nexus0
Depends on D7552