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@(#)autoconf.4 6.2 (Berkeley) 06/30/87

C 7 autoconf - diagnostics from autoconfiguration code When UNIX bootstraps it probes the innards of the machine it is running on and locates controllers, drives, and other devices, printing out what it finds on the console. This procedure is driven by a system configuration table which is processed by config (8) and compiled into each kernel.

VERSAbus devices are located by probing to see if their control-status registers respond. If not, they are silently ignored. If the control status register responds but the device cannot be made to interrupt, a diagnostic warning will be printed on the console and the device will not be available to the system.

A generic system may be built which picks its root device at boot time as the ``best'' available device. If such a system is booted with the RB_ASKNAME option of (see reboot (2v)), then the name of the root device is read from the console terminal at boot time, and any available device may be used.

config(8) vba%d at %x. A VERSAbus adapter was found and mapped into the address space of the operating system starting at virtual address %x. UNIX will call it vba%d.

%s%d at vba%d drive %d. A tape formatter or a disk was found on the VERSAbus; for disks %s%d will look like ``dk0'', for tape formatters like ``yc1''. The drive number comes from the unit plug on the drive or in the tape formatter (not on the tape drive; see below).

%s%d at %s%d slave %d. Which would look like ``yc0 at cy0 slave 0'', where yc0 is the name for the tape device and cy0 is the name for the formatter. A tape slave was found on the tape formatter at the indicated drive number (on the front of the tape drive). UNIX will call the device, e.g., cy0.

%s%d at vba%d csr %x vec %x ipl %x. The device %s%d, e.g. vd0 was found on vba%d at control-status register address %x and with device vector %x. The device interrupted at priority level %x.

%s%d at vba%d csr %x no interrupts. The device was found on vba%d at control-status register address %x; no interrupts were configured for the device.

%s%d at vba%d csr %x didn't interrupt. The device did not interrupt, likely because it is broken, hung, or not the kind of device it is advertised to be. The csr address is interpreted as described above.

%s%d at %s%d slave %d. Which would look like ``dk0 at vd0 slave 0'', where dk0 is the name of a disk drive and vd0 is the name of the controller.

Very few devices actually figure out their interrupt vector by forcing the device to interrupt. Only the upper megabyte of the VERSAbus address space is mapped into the system's virtual address space.