Navigating the Device Tree

MDB provides the ::prtconf dcmd to display the kernel device tree. The output of this dcmd is similar to the output of the prtconf(1M) command:

> ::prtconf
DEVINFO  NAME
704c9f00 SUNW,Ultra-1
    704c9e00 packages (driver not attached)
        704c9c00 terminal-emulator (driver not attached)
        704c9b00 deblocker (driver not attached)
        704c9a00 obp-tftp (driver not attached)
        704c9900 disk-label (driver not attached)
        704c9800 sun-keyboard (driver not attached)
        704c9700 ufs-file-system (driver not attached)
    704c9d00 chosen (driver not attached)
    704c9600 openprom (driver not attached)
        704c9400 client-services (driver not attached)
    704c9500 options, instance #0
    704c9300 aliases (driver not attached)
    704c9200 memory (driver not attached)
    704c9100 virtual-memory (driver not attached)
    704c9000 counter-timer (driver not attached)
    704c8f00 sbus, instance #0
        704c8d00 SUNW,CS4231 (driver not attached)
        704c8c00 auxio (driver not attached)
        704c8b00 flashprom (driver not attached)
        704c8a00 SUNW,fdtwo (driver not attached)
...

Each line of output represents a node in the kernel's device tree. The address to the left of each node name is the address of the devinfo node. The node can then be displayed using the $<devinfo macro or the ::devinfo dcmd:

> 704c9f00::devinfo
704c9f00 SUNW,Ultra-1
         Driver properties at 0x704bb208:
           pm-hardware-state: "no-suspend-resume"
         System properties at 0x704bb190:
           relative-addressing: 0x1
           MMU_PAGEOFFSET: 0x1fff
           MMU_PAGESIZE: 0x2000
           PAGESIZE: 0x2000

> 704c9f00$<devinfo
0x704cbd20:
                name:
SUNW,Ultra-1
0x704c9f00:     parent          child           sibling
                0               704c9e00        0
0x704c9f10:     addr            nodeid          instance
                704be758        f00297e4        ffffffff
0x704c9f1c:     ops             parent_data     driver_data
                rootnex_ops     702baad0        0
0x704c9f28:     drv_prop_ptr    sys_prop_ptr    minor
                704bb208        704bb190        0
0x704c9f34:     next
                0

Use ::prtconf to see where your driver has attached in the device tree, and to display device properties. You can also specify the verbose (-v) flag to ::prtconf to display the properties for each device node:

> ::prtconf -v
DEVINFO  NAME
704c9f00 SUNW,Ultra-1
         Driver properties at 0x704bb208:
           pm-hardware-state: "no-suspend-resume"
         System properties at 0x704bb190:
           relative-addressing: 0x1
           MMU_PAGEOFFSET: 0x1fff
           MMU_PAGESIZE: 0x2000
           PAGESIZE: 0x2000
         ...
         704c8400 espdma, instance #0
            704c8200 esp, instance #0
                     Driver properties at 0x702ba7d8:
                       target0-sync-speed: 0x2710
                       target0-TQ
                       scsi-selection-timeout: <000000fa.> (device: <0x3d/0x
                       00000000>)
                       scsi-options: <00001ff8.> (device: <0x3d/0x00000000>)
                       scsi-watchdog-tick: <0000000a.> (device: <0x3d/0x00000000>)
                       scsi-tag-age-limit: <00000002.> (device: <0x3d/0x00000000>)
                       scsi-reset-delay: <00000bb8.> (device: <0x3d/0x00000000>)
         ...
                704c7c00 sd, instance #1 (driver not attached)
                         System properties at 0x704ba4e8:
                           lun: 0x0
                           target: 0x1
                           class_prop: "atapi"
                           class: "scsi"
         ...

Another way to locate instances of your driver is the ::devbindings dcmd. Given a driver name, it displays a list of all instances of the named driver:

> ::devbindings sd
704c8100 sd (driver not attached)
704c7d00 sd, instance #0
         Driver properties at 0x702ba5a8:
           pm-hardware-state: "needs-suspend-resume"
           ddi-kernel-ioctl
         System properties at 0x704ba588:
           lun: 0x0
           target: 0x0
           class_prop: "atapi"
           class: "scsi"
704c7c00 sd, instance #1 (driver not attached)
         System properties at 0x704ba4e8:
           lun: 0x0
           target: 0x1
           class_prop: "atapi"
           class: "scsi"
704c7b00 sd, instance #2 (driver not attached)
         System properties at 0x704ba448:
           lun: 0x0
           target: 0x2
           class_prop: "atapi"
           class: "scsi"
...