iokit/IOKit/IODeviceMemory.h

   1 /*
   2  * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23 /*
  24  * Copyright (c) 1998 Apple Computer, Inc.  All rights reserved.
  25  *
  26  * HISTORY
  27  *
  28  */
  29
  30 #ifndef _IOKIT_IODEVICEMEMORY_H
  31 #define _IOKIT_IODEVICEMEMORY_H
  32
  33 #include <IOKit/IOMemoryDescriptor.h>
  34
  35 /*! @class IODeviceMemory
  36     @abstract An IOMemoryDescriptor used for device physical memory ranges.
  37     @discussion The IODeviceMemory class is a simple subclass of IOMemoryDescriptor that uses its methods to describe a single range of physical memory on a device. IODeviceMemory objects are usually looked up with IOService or IOPCIDevice accessors, and are created by memory-mapped bus families. IODeviceMemory implements only some factory methods in addition to the methods of IOMemoryDescriptor.
  38 */
  39
  40 class IODeviceMemory : public IOMemoryDescriptor
  41 {
  42     OSDeclareDefaultStructors(IODeviceMemory)
  43
  44 public:
  45
  46 /*! @struct InitElement
  47     @field start First physical address in the range.
  48     @field length Length of the range.
  49     @field tag 32-bit value not interpreted by IODeviceMemory or IOMemoryDescriptor, for use by the bus family. */
  50
  51     struct InitElement {
  52         IOPhysicalAddress       start;
  53         IOPhysicalLength        length;
  54         IOOptionBits            tag;
  55     };
  56
  57 /*! @function arrayFromList
  58     @abstract Constructs an OSArray of IODeviceMemory instances, each describing one physical range, and a tag value.
  59     @discussion This method creates IODeviceMemory instances for each physical range passed in an IODeviceMemory::InitElement array. Each element consists of a physical address, length and tag value for the IODeviceMemory. The instances are returned as a created OSArray.
  60     @param list An array of IODeviceMemory::InitElement structures.
  61     @param count The number of elements in the list.
  62     @result Returns a created OSArray of IODeviceMemory objects, to be released by the caller, or zero on failure. */
  63
  64     static OSArray *            arrayFromList(
  65         InitElement             list[],
  66         IOItemCount             count );
  67
  68 /*! @function withRange
  69     @abstract Constructs an IODeviceMemory instance, describing one physical range.
  70     @discussion This method creates an IODeviceMemory instance for one physical range passed as a physical address and length. It just calls IOMemoryDescriptor::withPhysicalAddress.
  71     @param address The physical address of the first byte in the memory.
  72     @param withLength The length of memory.
  73     @result Returns the created IODeviceMemory on success, to be released by the caller, or zero on failure. */
  74
  75     static IODeviceMemory *     withRange(
  76         IOPhysicalAddress       start,
  77         IOPhysicalLength        length );
  78
  79 /*! @function withSubRange
  80     @abstract Constructs an IODeviceMemory instance, describing a subset of an existing IODeviceMemory range.
  81     @discussion This method creates an IODeviceMemory instance for a subset of an existing IODeviceMemory range, passed as a physical address offset and length. It just calls IOMemoryDescriptor::withSubRange.
  82     @param of The parent IODeviceMemory of which a subrange is to be used for the new descriptor, which will be retained by the subrange IODeviceMemory.
  83     @param offset A byte offset into the parent's memory.
  84     @param length The length of the subrange.
  85     @result Returns the created IODeviceMemory on success, to be released by the caller, or zero on failure. */
  86
  87     static IODeviceMemory *     withSubRange(
  88         IODeviceMemory *        of,
  89         IOPhysicalAddress       offset,
  90         IOPhysicalLength        length );
  91 };
  92
  93 #endif /* ! _IOKIT_IODEVICEMEMORY_H */