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HIGHPOINT ROCKETRAID 3xxx RAID DRIVER (hptiop)

Controller Register Map
-------------------------

The controller IOP is accessed via PCI BAR0.

     BAR0 offset    Register
            0x10    Inbound Message Register 0
            0x14    Inbound Message Register 1
            0x18    Outbound Message Register 0
            0x1C    Outbound Message Register 1
            0x20    Inbound Doorbell Register
            0x24    Inbound Interrupt Status Register
            0x28    Inbound Interrupt Mask Register
            0x30    Outbound Interrupt Status Register
            0x34    Outbound Interrupt Mask Register
            0x40    Inbound Queue Port
            0x44    Outbound Queue Port


I/O Request Workflow
----------------------

All queued requests are handled via inbound/outbound queue port.
A request packet can be allocated in either IOP or host memory.

To send a request to the controller:

    - Get a free request packet by reading the inbound queue port or
      allocate a free request in host DMA coherent memory.

      The value returned from the inbound queue port is an offset
      relative to the IOP BAR0.

      Requests allocated in host memory must be aligned on 32-bytes boundary.

    - Fill the packet.

    - Post the packet to IOP by writing it to inbound queue. For requests
      allocated in IOP memory, write the offset to inbound queue port. For
      requests allocated in host memory, write (0x80000000|(bus_addr>>5))
      to the inbound queue port.

    - The IOP process the request. When the request is completed, it
      will be put into outbound queue. An outbound interrupt will be
      generated.

      For requests allocated in IOP memory, the request offset is posted to
      outbound queue.

      For requests allocated in host memory, (0x80000000|(bus_addr>>5))
      is posted to the outbound queue. If IOP_REQUEST_FLAG_OUTPUT_CONTEXT
      flag is set in the request, the low 32-bit context value will be
      posted instead.

    - The host read the outbound queue and complete the request.

      For requests allocated in IOP memory, the host driver free the request
      by writing it to the outbound queue.

Non-queued requests (reset/flush etc) can be sent via inbound message
register 0. An outbound message with the same value indicates the completion
of an inbound message.


User-level Interface
---------------------

The driver exposes following sysfs attributes:

     NAME                 R/W    Description
     driver-version        R     driver version string
     firmware-version      R     firmware version string

The driver registers char device "hptiop" to communicate with HighPoint RAID
management software. Its ioctl routine acts as a general binary interface 
between the IOP firmware and HighPoint RAID management software. New management
functions can be implemented in application/firmware without modification
in driver code.


-----------------------------------------------------------------------------
Copyright (C) 2006 HighPoint Technologies, Inc. All Rights Reserved.

  This file is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  linux@highpoint-tech.com
  http://www.highpoint-tech.com