direct/yaffs_flashif.c

   1 /*
   2  * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
   3  *
   4  * Copyright (C) 2002-2007 Aleph One Ltd.
   5  *   for Toby Churchill Ltd and Brightstar Engineering
   6  *
   7  * Created by Charles Manning <charles@aleph1.co.uk>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12  *
  13  */
  14
  15
  16 const char *yaffs_flashif_c_version = "$Id: yaffs_flashif.c,v 1.2 2007-02-12 16:49:50 wookey Exp $";
  17
  18
  19 #include "yportenv.h"
  20
  21 #include "yaffs_flashif.h"
  22 #include "yaffs_guts.h"
  23 #include "devextras.h"
  24
  25
  26 #define SIZE_IN_MB 16
  27
  28 #define BLOCK_SIZE (32 * 528)
  29 #define BLOCKS_PER_MEG ((1024*1024)/(32 * 512))
  30
  31
  32
  33 typedef struct
  34 {
  35         __u8 data[528]; // Data + spare
  36 } yflash_Page;
  37
  38 typedef struct
  39 {
  40         yflash_Page page[32]; // The pages in the block
  41
  42 } yflash_Block;
  43
  44
  45
  46 typedef struct
  47 {
  48         yflash_Block **block;
  49         int nBlocks;
  50 } yflash_Device;
  51
  52 static yflash_Device ramdisk;
  53
  54 static int  CheckInit(yaffs_Device *dev)
  55 {
  56         static int initialised = 0;
  57
  58         int i;
  59         int fail = 0;
  60         int nAllocated = 0;
  61
  62         if(initialised)
  63         {
  64                 return YAFFS_OK;
  65         }
  66
  67         initialised = 1;
  68
  69
  70         ramdisk.nBlocks = (SIZE_IN_MB * 1024 * 1024)/(16 * 1024);
  71
  72         ramdisk.block = YMALLOC(sizeof(yflash_Block *) * ramdisk.nBlocks);
  73
  74         if(!ramdisk.block) return 0;
  75
  76         for(i=0; i <ramdisk.nBlocks; i++)
  77         {
  78                 ramdisk.block[i] = NULL;
  79         }
  80
  81         for(i=0; i <ramdisk.nBlocks && !fail; i++)
  82         {
  83                 if((ramdisk.block[i] = YMALLOC(sizeof(yflash_Block))) == 0)
  84                 {
  85                         fail = 1;
  86                 }
  87                 else
  88                 {
  89                         yflash_EraseBlockInNAND(dev,i);
  90                         nAllocated++;
  91                 }
  92         }
  93
  94         if(fail)
  95         {
  96                 for(i = 0; i < nAllocated; i++)
  97                 {
  98                         YFREE(ramdisk.block[i]);
  99                 }
 100                 YFREE(ramdisk.block);
 101
 102                 T(YAFFS_TRACE_ALWAYS,("Allocation failed, could only allocate %dMB of %dMB requested.\n",
 103                    nAllocated/64,ramdisk.nBlocks * YAFFS_BYTES_PER_BLOCK));
 104                 return 0;
 105         }
 106
 107
 108
 109         return 1;
 110 }
 111
 112 int yflash_WriteChunkWithTagsToNAND(yaffs_Device *dev,int chunkInNAND,const __u8 *data, yaffs_ExtendedTags *tags)
 113 {
 114         int blk;
 115         int pg;
 116
 117
 118         CheckInit(dev);
 119
 120         blk = chunkInNAND/32;
 121         pg = chunkInNAND%32;
 122
 123
 124         if(data)
 125         {
 126                 memcpy(ramdisk.block[blk]->page[pg].data,data,512);
 127         }
 128
 129
 130         if(tags)
 131         {
 132                 yaffs_PackedTags pt;
 133                 yaffs_PackTags(&pt,tags);
 134                 memcpy(&ramdisk.block[blk]->page[pg].data[512],&pt,sizeof(pt));
 135         }
 136
 137         return YAFFS_OK;
 138
 139 }
 140
 141
 142 int yflash_ReadChunkWithTagsFromNAND(yaffs_Device *dev,int chunkInNAND, __u8 *data, yaffs_Tags *tags)
 143 {
 144         int blk;
 145         int pg;
 146
 147
 148         CheckInit(dev);
 149
 150         blk = chunkInNAND/32;
 151         pg = chunkInNAND%32;
 152
 153
 154         if(data)
 155         {
 156                 memcpy(data,ramdisk.block[blk]->page[pg].data,512);
 157         }
 158
 159
 160         if(tags)
 161         {
 162                 yaffs_PackedTags pt;
 163                 memcpy(&pt,&ramdisk.block[blk]->page[pg].data[512],sizeof(yaffs_PackedTags));
 164                 yaffs_UnpackTags(tags,&pt);
 165         }
 166
 167         return YAFFS_OK;
 168 }
 169
 170
 171 int yflash_CheckChunkErased(yaffs_Device *dev,int chunkInNAND)
 172 {
 173         int blk;
 174         int pg;
 175         int i;
 176
 177
 178         CheckInit(dev);
 179
 180         blk = chunkInNAND/32;
 181         pg = chunkInNAND%32;
 182
 183
 184         for(i = 0; i < 528; i++)
 185         {
 186                 if(ramdisk.block[blk]->page[pg].data[i] != 0xFF)
 187                 {
 188                         return YAFFS_FAIL;
 189                 }
 190         }
 191
 192         return YAFFS_OK;
 193
 194 }
 195
 196 int yflash_EraseBlockInNAND(yaffs_Device *dev, int blockNumber)
 197 {
 198
 199         CheckInit(dev);
 200
 201         if(blockNumber < 0 || blockNumber >= ramdisk.nBlocks)
 202         {
 203                 T(YAFFS_TRACE_ALWAYS,("Attempt to erase non-existant block %d\n",blockNumber));
 204                 return YAFFS_FAIL;
 205         }
 206         else
 207         {
 208                 memset(ramdisk.block[blockNumber],0xFF,sizeof(yflash_Block));
 209                 return YAFFS_OK;
 210         }
 211
 212 }
 213
 214 int yflash_MarkNANDBlockBad(struct yaffs_DeviceStruct *dev, int blockNo)
 215 {
 216         return YAFFS_OK;
 217
 218 }
 219 int yflash_QueryNANDBlock(struct yaffs_DeviceStruct *dev, int blockNo, yaffs_BlockState *state, int *sequenceNumber)
 220 {
 221         *state = YAFFS_BLOCK_STATE_EMPTY;
 222         *sequenceNumber = 0;
 223 }
 224
 225
 226 int yflash_InitialiseNAND(yaffs_Device *dev)
 227 {
 228         return YAFFS_OK;
 229 }
 230