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diff --git a/Documentation/driver-api/sgi-ioc4.rst b/Documentation/driver-api/sgi-ioc4.rst deleted file mode 100644 index 72709222d3c0..000000000000 --- a/Documentation/driver-api/sgi-ioc4.rst +++ /dev/null @@ -1,49 +0,0 @@ -==================================== -SGI IOC4 PCI (multi function) device -==================================== - -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. |