iokit/Drivers/platform/drvAppleNVRAM/AppleNVRAM.cpp

   1 /*
   2  * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
   7  *
   8  * This file contains Original Code and/or Modifications of Original Code
   9  * as defined in and that are subject to the Apple Public Source License
  10  * Version 2.0 (the 'License'). You may not use this file except in
  11  * compliance with the License. Please obtain a copy of the License at
  12  * http://www.opensource.apple.com/apsl/ and read it before using this
  13  * file.
  14  *
  15  * The Original Code and all software distributed under the License are
  16  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  17  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  18  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  20  * Please see the License for the specific language governing rights and
  21  * limitations under the License.
  22  *
  23  * @APPLE_LICENSE_HEADER_END@
  24  */
  25
  26 #include <IOKit/IOLib.h>
  27 #include "AppleNVRAM.h"
  28
  29
  30 #define super IONVRAMController
  31 OSDefineMetaClassAndStructors(AppleNVRAM, IONVRAMController);
  32
  33
  34 // ****************************************************************************
  35 // start
  36 //
  37 // ****************************************************************************
  38 bool AppleNVRAM::start(IOService *provider)
  39 {
  40   IOItemCount numRanges;
  41   IOMemoryMap *map;
  42
  43   numRanges = provider->getDeviceMemoryCount();
  44
  45   if (numRanges == 1) {
  46     _nvramType = kNVRAMTypeIOMem;
  47
  48     // Get the address of the data register.
  49     map = provider->mapDeviceMemoryWithIndex(0);
  50     if (map == 0) return false;
  51     _nvramData = (UInt8 *)map->getVirtualAddress();
  52
  53   } else if (numRanges == 2) {
  54     _nvramType = kNVRAMTypePort;
  55
  56     // Get the address of the port register.
  57     map = provider->mapDeviceMemoryWithIndex(0);
  58     if (map == 0) return false;
  59     _nvramPort = (UInt8 *)map->getVirtualAddress();
  60
  61     // Get the address of the data register.
  62     map = provider->mapDeviceMemoryWithIndex(1);
  63     if (map == 0) return false;
  64     _nvramData = (UInt8 *)map->getVirtualAddress();
  65
  66   } else {
  67     return false;
  68   }
  69
  70   return super::start(provider);
  71 }
  72
  73 // ****************************************************************************
  74 // read
  75 //
  76 // Read data from the NVRAM and return it in buffer.
  77 //
  78 // ****************************************************************************
  79 IOReturn AppleNVRAM::read(IOByteCount offset, UInt8 *buffer,
  80                           IOByteCount length)
  81 {
  82   UInt32 cnt;
  83
  84   if ((buffer == 0) || (length <= 0) || (offset < 0) ||
  85       (offset + length > kNVRAMImageSize))
  86     return kIOReturnBadArgument;
  87
  88   switch (_nvramType) {
  89   case kNVRAMTypeIOMem :
  90     for (cnt = 0; cnt < length; cnt++) {
  91       buffer[cnt] = _nvramData[(offset + cnt)  << 4];
  92     }
  93     break;
  94
  95   case kNVRAMTypePort:
  96     for (cnt = 0; cnt < length; cnt++) {
  97       *_nvramPort = (offset + length) >> 5;
  98       eieio();
  99       buffer[cnt] = _nvramData[((offset + length) & 0x1F) << 4];
 100     }
 101     break;
 102
 103   default :
 104     return kIOReturnNotReady;
 105   }
 106
 107   return kIOReturnSuccess;
 108 }
 109
 110
 111 // ****************************************************************************
 112 // write
 113 //
 114 // Write data from buffer into NVRAM.
 115 //
 116 // ****************************************************************************
 117 IOReturn AppleNVRAM::write(IOByteCount offset, UInt8 *buffer,
 118                            IOByteCount length)
 119 {
 120   UInt32 cnt;
 121
 122   if ((buffer == 0) || (length <= 0) || (offset < 0) ||
 123       (offset + length > kNVRAMImageSize))
 124     return kIOReturnBadArgument;
 125
 126   switch (_nvramType) {
 127   case kNVRAMTypeIOMem :
 128     for (cnt = 0; cnt < length; cnt++) {
 129       _nvramData[(offset + cnt)  << 4] = buffer[cnt];
 130       eieio();
 131     }
 132     break;
 133
 134   case kNVRAMTypePort:
 135     for (cnt = 0; cnt < length; cnt++) {
 136       *_nvramPort = (offset + length) >> 5;
 137       eieio();
 138       _nvramData[((offset + length) & 0x1F) << 4] = buffer[cnt];
 139       eieio();
 140     }
 141     break;
 142
 143   default :
 144     return kIOReturnNotReady;
 145   }
 146
 147   return kIOReturnSuccess;
 148 }