HP-UX 11i June 2001 Release Notes

Workstation/Server Specific Information
N4000 Server Functionality
Chapter 3 61
the base address registers.
On N4000 systems, the firmware programs only the boot and console
devices. The PCI CDIO must program the remaining devices, using
information provided by firmware to the operating system (PAT PSM
gets this for PCI).
The N4000 disassociates interrupt routing/handling from the platform-
specific bus adapter. On legacy PCI systems, the interrupt lines are
routed to the PCI host bus-adapter chip and handled by the same driver
(for example, GSCtoPCI and EPIC CDIOs). On N4000 systems, though
the interrupt lines are routed to the LBA (PCI bus interface chip), SAPIC
PSM handles the interrupt support instead of the LBA CDIO.
LBA CDIO provides N4000 specific services to support PCI drivers and
access to the PCI bus. Legacy PCI bus adapter drivers have been
modified to be compatible with the new PCI CDIO.
PCItoPCI CDIO
The restructuring of the PCI subsystem permits PCItoPCI configuration
of devices to more than two bridges deep. There is no new functionality
for this release.