yaffs_flashif.c revision 40c4004d07a37a9b140067f893930ce4436b9346 
1/*
2 * YAFFS: Yet another FFS. A NAND-flash specific file system.
3 * yaffs_ramdisk.c: yaffs ram disk component
4 *
5 * Copyright (C) 2002 Aleph One Ltd.
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// This provides a rma disk under yaffs.
16// NB this is not intended for NAND emulation.
17// Use this with dev->useNANDECC enabled, then ECC overheads are not required.
18
19const char *yaffs_flashif_c_version = "$Id: yaffs_flashif.c,v 1.1 2004/11/03 08:29:28 charles Exp $";
20
21
22#include "yportenv.h"
23
24#include "yaffs_flashif.h"
25#include "yaffs_guts.h"
26#include "devextras.h"
27
28
29#define SIZE_IN_MB 16
30
31#define BLOCK_SIZE (32 * 528)
32#define BLOCKS_PER_MEG ((1024*1024)/(32 * 512))
33
34
35
36typedef struct
37{
38	__u8 data[528]; // Data + spare
39} yflash_Page;
40
41typedef struct
42{
43	yflash_Page page[32]; // The pages in the block
44
45} yflash_Block;
46
47
48
49typedef struct
50{
51	yflash_Block **block;
52	int nBlocks;
53} yflash_Device;
54
55static yflash_Device ramdisk;
56
57static int  CheckInit(yaffs_Device *dev)
58{
59	static int initialised = 0;
60
61	int i;
62	int fail = 0;
63	int nAllocated = 0;
64
65	if(initialised)
66	{
67		return YAFFS_OK;
68	}
69
70	initialised = 1;
71
72
73	ramdisk.nBlocks = (SIZE_IN_MB * 1024 * 1024)/(16 * 1024);
74
75	ramdisk.block = YMALLOC(sizeof(yflash_Block *) * ramdisk.nBlocks);
76
77	if(!ramdisk.block) return 0;
78
79	for(i=0; i <ramdisk.nBlocks; i++)
80	{
81		ramdisk.block[i] = NULL;
82	}
83
84	for(i=0; i <ramdisk.nBlocks && !fail; i++)
85	{
86		if((ramdisk.block[i] = YMALLOC(sizeof(yflash_Block))) == 0)
87		{
88			fail = 1;
89		}
90		else
91		{
92			yflash_EraseBlockInNAND(dev,i);
93			nAllocated++;
94		}
95	}
96
97	if(fail)
98	{
99		for(i = 0; i < nAllocated; i++)
100		{
101			YFREE(ramdisk.block[i]);
102		}
103		YFREE(ramdisk.block);
104
105		T(YAFFS_TRACE_ALWAYS,("Allocation failed, could only allocate %dMB of %dMB requested.\n",
106		   nAllocated/64,ramdisk.nBlocks * YAFFS_BYTES_PER_BLOCK));
107		return 0;
108	}
109
110
111
112	return 1;
113}
114
115int yflash_WriteChunkWithTagsToNAND(yaffs_Device *dev,int chunkInNAND,const __u8 *data, yaffs_ExtendedTags *tags)
116{
117	int blk;
118	int pg;
119
120
121	CheckInit(dev);
122
123	blk = chunkInNAND/32;
124	pg = chunkInNAND%32;
125
126
127	if(data)
128	{
129		memcpy(ramdisk.block[blk]->page[pg].data,data,512);
130	}
131
132
133	if(tags)
134	{
135		yaffs_PackedTags pt;
136		yaffs_PackTags(&pt,tags);
137		memcpy(&ramdisk.block[blk]->page[pg].data[512],&pt,sizeof(pt));
138	}
139
140	return YAFFS_OK;
141
142}
143
144
145int yflash_ReadChunkWithTagsFromNAND(yaffs_Device *dev,int chunkInNAND, __u8 *data, yaffs_Tags *tags)
146{
147	int blk;
148	int pg;
149
150
151	CheckInit(dev);
152
153	blk = chunkInNAND/32;
154	pg = chunkInNAND%32;
155
156
157	if(data)
158	{
159		memcpy(data,ramdisk.block[blk]->page[pg].data,512);
160	}
161
162
163	if(tags)
164	{
165		yaffs_PackedTags pt;
166		memcpy(&pt,&ramdisk.block[blk]->page[pg].data[512],sizeof(yaffs_PackedTags));
167		yaffs_UnpackTags(tags,&pt);
168	}
169
170	return YAFFS_OK;
171}
172
173
174int yflash_CheckChunkErased(yaffs_Device *dev,int chunkInNAND)
175{
176	int blk;
177	int pg;
178	int i;
179
180
181	CheckInit(dev);
182
183	blk = chunkInNAND/32;
184	pg = chunkInNAND%32;
185
186
187	for(i = 0; i < 528; i++)
188	{
189		if(ramdisk.block[blk]->page[pg].data[i] != 0xFF)
190		{
191			return YAFFS_FAIL;
192		}
193	}
194
195	return YAFFS_OK;
196
197}
198
199int yflash_EraseBlockInNAND(yaffs_Device *dev, int blockNumber)
200{
201
202	CheckInit(dev);
203
204	if(blockNumber < 0 || blockNumber >= ramdisk.nBlocks)
205	{
206		T(YAFFS_TRACE_ALWAYS,("Attempt to erase non-existant block %d\n",blockNumber));
207		return YAFFS_FAIL;
208	}
209	else
210	{
211		memset(ramdisk.block[blockNumber],0xFF,sizeof(yflash_Block));
212		return YAFFS_OK;
213	}
214
215}
216
217int yflash_MarkNANDBlockBad(struct yaffs_DeviceStruct *dev, int blockNo)
218{
219	return YAFFS_OK;
220
221}
222int yflash_QueryNANDBlock(struct yaffs_DeviceStruct *dev, int blockNo, yaffs_BlockState *state, int *sequenceNumber)
223{
224	*state = YAFFS_BLOCK_STATE_EMPTY;
225	*sequenceNumber = 0;
226}
227
228
229int yflash_InitialiseNAND(yaffs_Device *dev)
230{
231	return YAFFS_OK;
232}
233
234