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-The SGI IOC4 PCI device is a bit of a strange beast, so some notes on
-it are in order.
-
-First, even though the IOC4 performs multiple functions, such as an
-IDE controller, a serial controller, a PS/2 keyboard/mouse controller,
-and an external interrupt mechanism, it's not implemented as a
-multifunction device. The consequence of this from a software
-standpoint is that all these functions share a single IRQ, and
-they can't all register to own the same PCI device ID. To make
-matters a bit worse, some of the register blocks (and even registers
-themselves) present in IOC4 are mixed-purpose between these several
-functions, meaning that there's no clear "owning" device driver.
-
-The solution is to organize the IOC4 driver into several independent
-drivers, "ioc4", "sgiioc4", and "ioc4_serial". Note that there is no
-PS/2 controller driver as this functionality has never been wired up
-on a shipping IO card.
-
-ioc4
-====
-This is the core (or shim) driver for IOC4. It is responsible for
-initializing the basic functionality of the chip, and allocating
-the PCI resources that are shared between the IOC4 functions.
-
-This driver also provides registration functions that the other
-IOC4 drivers can call to make their presence known. Each driver
-needs to provide a probe and remove function, which are invoked
-by the core driver at appropriate times. The interface of these
-IOC4 function probe and remove operations isn't precisely the same
-as PCI device probe and remove operations, but is logically the
-same operation.
-
-sgiioc4
-=======
-This is the IDE driver for IOC4. Its name isn't very descriptive
-simply for historical reasons (it used to be the only IOC4 driver
-component). There's not much to say about it other than it hooks
-up to the ioc4 driver via the appropriate registration, probe, and
-remove functions.
-
-ioc4_serial
-===========
-This is the serial driver for IOC4. There's not much to say about it
-other than it hooks up to the ioc4 driver via the appropriate registration,
-probe, and remove functions.