2 * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
4 * Copyright (C) 2002-2011 Aleph One Ltd.
5 * for Toby Churchill Ltd and Brightstar Engineering
7 * Created by Charles Manning <charles@aleph1.co.uk>
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.
15 * This is an interface module for handling NOR in yaffs1 mode.
18 /* First set up for M18 with 1k chunks and 16-byte spares.
20 * NB We're using the oddball M18 modes of operation here
21 * The chip is 64MB based at 0x0000, but YAFFS only going to use the top half
22 * ie. YAFFS will be from 32MB to 64MB.
24 * The M18 has two ways of writing data. Every Programming Region (1kbytes)
25 * can be programmed in two modes:
26 * * Object Mode 1024 bytes of write once data.
27 * * Control Mode: 512bytes of bit-writeable data.
28 * This is arranged as 32 * (16 bytes of bit-writable followed by 16 bytes of "dont touch")
30 * The block size is 256kB, making 128 blocks in the 32MB YAFFS area.
31 * Each block comprises:
32 * Offset 0k: 248 x 1k data pages
33 * Offset 248k: 248 x 32-byte spare areas implemented as 16 bytes of spare followed by 16 bytes untouched)
34 * Offset 248k + (248 * 32): Format marker
38 #include "yaffs_m18_drv.h"
41 #include "yaffs_trace.h"
43 #include "yaffs_flashif.h"
44 #include "yaffs_guts.h"
46 #define SPARE_BYTES_PER_CHUNK 16
48 #define PROG_REGION_SIZE 1024
49 #define BLOCK_SIZE_IN_BYTES (256*1024)
50 #define CHUNKS_PER_BLOCK 248
51 #define SPARE_AREA_OFFSET (CHUNKS_PER_BLOCK * PROG_REGION_SIZE)
53 #define FORMAT_OFFSET (SPARE_AREA_OFFSET + CHUNKS_PER_BLOCK * \
54 (SPARE_BYTES_PER_CHUNK + M18_SKIP))
56 #define FORMAT_VALUE 0x1234
58 #define DATA_BYTES_PER_CHUNK 1024
59 #define BLOCKS_IN_DEVICE (8*1024/256)
62 #define YNOR_PREMARKER (0xF6)
63 #define YNOR_POSTMARKER (0xF0)
68 /* Compile this for a simulation */
70 #define m18_drv_FlashInit() ynorsim_initialise()
71 #define m18_drv_FlashDeinit() ynorsim_shutdown()
72 #define m18_drv_FlashWrite32(addr,buf,nwords) ynorsim_wr32(addr,buf,nwords)
73 #define m18_drv_FlashRead32(addr,buf,nwords) ynorsim_rd32(addr,buf,nwords)
74 #define m18_drv_FlashEraseBlock(addr) ynorsim_erase(addr)
75 #define DEVICE_BASE ynorsim_get_base()
78 /* Compile this to hook up to read hardware */
79 #include "../blob/yflashrw.h"
80 #define m18_drv_FlashInit() do{} while(0)
81 #define m18_drv_FlashDeinit() do {} while(0)
82 #define m18_drv_FlashWrite32(addr,buf,nwords) Y_FlashWrite(addr,buf,nwords)
83 #define m18_drv_FlashRead32(addr,buf,nwords) Y_FlashRead(addr,buf,nwords)
84 #define m18_drv_FlashEraseBlock(addr) Y_FlashErase(addr,BLOCK_SIZE_IN_BYTES)
85 #define DEVICE_BASE (32 * 1024 * 1024)
88 static u32 *Block2Addr(struct yaffs_dev *dev, int blockNumber)
93 addr = (u32) DEVICE_BASE;
94 addr += blockNumber * BLOCK_SIZE_IN_BYTES;
99 static u32 *Block2FormatAddr(struct yaffs_dev *dev,int blockNumber)
103 addr = (u32) Block2Addr(dev,blockNumber);
104 addr += FORMAT_OFFSET;
109 static u32 *Chunk2DataAddr(struct yaffs_dev *dev,int chunk_id)
112 unsigned chunkInBlock;
115 block = chunk_id/dev->param.chunks_per_block;
116 chunkInBlock = chunk_id % dev->param.chunks_per_block;
118 addr = (u32) Block2Addr(dev,block);
119 addr += chunkInBlock * DATA_BYTES_PER_CHUNK;
124 static u32 *Chunk2SpareAddr(struct yaffs_dev *dev,int chunk_id)
127 unsigned chunkInBlock;
130 block = chunk_id/dev->param.chunks_per_block;
131 chunkInBlock = chunk_id % dev->param.chunks_per_block;
133 addr = (u32) Block2Addr(dev,block);
134 addr += SPARE_AREA_OFFSET;
135 addr += chunkInBlock * (SPARE_BYTES_PER_CHUNK + M18_SKIP);
140 static void m18_drv_AndBytes(u8*target, const u8 *src, int nbytes)
150 static int m18_drv_WriteChunkToNAND(struct yaffs_dev *dev,int nand_chunk,
151 const u8 *data, int data_len,
152 const u8 *oob, int oob_len)
154 u32 *dataAddr = Chunk2DataAddr(dev,nand_chunk);
155 u32 *spareAddr = Chunk2SpareAddr(dev,nand_chunk);
157 struct yaffs_spare *spare = (struct yaffs_spare *)oob;
158 struct yaffs_spare tmpSpare;
162 /* We should only be getting called for one of 3 reasons:
163 * Writing a chunk: data and spare will not be NULL
164 * Writing a deletion marker: data will be NULL, spare not NULL
165 * Writing a bad block marker: data will be NULL, spare not NULL
168 if(sizeof(struct yaffs_spare) != 16)
173 if(spare->page_status != 0xff)
175 /* Write a pre-marker */
176 memset(&tmpSpare,0xff,sizeof(tmpSpare));
177 tmpSpare.page_status = YNOR_PREMARKER;
178 m18_drv_FlashWrite32(spareAddr,(u32 *)&tmpSpare,sizeof(struct yaffs_spare)/4);
181 m18_drv_FlashWrite32(dataAddr,(u32 *)data, data_len/ 4);
184 memcpy(&tmpSpare,spare,sizeof(struct yaffs_spare));
186 /* Write the real tags, but override the premarker*/
187 tmpSpare.page_status = YNOR_PREMARKER;
188 m18_drv_FlashWrite32(spareAddr,(u32 *)&tmpSpare,sizeof(struct yaffs_spare)/4);
190 /* Write a post-marker */
191 tmpSpare.page_status = YNOR_POSTMARKER;
192 m18_drv_FlashWrite32(spareAddr,(u32 *)&tmpSpare,sizeof(tmpSpare)/4);
195 /* This has to be a read-modify-write operation to handle NOR-ness */
197 m18_drv_FlashRead32(spareAddr,(u32 *)&tmpSpare,16/ 4);
199 m18_drv_AndBytes((u8 *)&tmpSpare,(u8 *)spare,sizeof(struct yaffs_spare));
201 m18_drv_FlashWrite32(spareAddr,(u32 *)&tmpSpare,16/ 4);
212 static int m18_drv_ReadChunkFromNAND(struct yaffs_dev *dev,int nand_chunk,
213 u8 *data, int data_len,
214 u8 *oob, int oob_len,
215 enum yaffs_ecc_result *ecc_result)
217 struct yaffs_spare *spare = (struct yaffs_spare *)oob;
219 u32 *dataAddr = Chunk2DataAddr(dev,nand_chunk);
220 u32 *spareAddr = Chunk2SpareAddr(dev,nand_chunk);
224 m18_drv_FlashRead32(dataAddr,(u32 *)data,dev->param.total_bytes_per_chunk / 4);
229 m18_drv_FlashRead32(spareAddr,(u32 *)spare, oob_len/ 4);
231 /* If the page status is YNOR_POSTMARKER then it was written properly
232 * so change that to 0xFF so that the rest of yaffs is happy.
234 if(spare->page_status == YNOR_POSTMARKER)
235 spare->page_status = 0xFF;
236 else if(spare->page_status != 0xff &&
237 (spare->page_status | YNOR_PREMARKER) != 0xff)
238 spare->page_status = YNOR_PREMARKER;
242 *ecc_result = YAFFS_ECC_RESULT_NO_ERROR;
249 static int m18_drv_FormatBlock(struct yaffs_dev *dev, int blockNumber)
251 u32 *blockAddr = Block2Addr(dev,blockNumber);
252 u32 *formatAddr = Block2FormatAddr(dev,blockNumber);
253 u32 formatValue = FORMAT_VALUE;
255 m18_drv_FlashEraseBlock(blockAddr);
256 m18_drv_FlashWrite32(formatAddr,&formatValue,1);
261 static int m18_drv_UnformatBlock(struct yaffs_dev *dev, int blockNumber)
263 u32 *formatAddr = Block2FormatAddr(dev,blockNumber);
266 m18_drv_FlashWrite32(formatAddr,&formatValue,1);
271 static int m18_drv_IsBlockFormatted(struct yaffs_dev *dev, int blockNumber)
273 u32 *formatAddr = Block2FormatAddr(dev,blockNumber);
277 m18_drv_FlashRead32(formatAddr,&formatValue,1);
279 return (formatValue == FORMAT_VALUE);
282 static int m18_drv_EraseBlockInNAND(struct yaffs_dev *dev, int blockNumber)
285 if(blockNumber < 0 || blockNumber >= BLOCKS_IN_DEVICE)
287 yaffs_trace(YAFFS_TRACE_ALWAYS,
288 "Attempt to erase non-existant block %d\n",
294 m18_drv_UnformatBlock(dev,blockNumber);
295 m18_drv_FormatBlock(dev,blockNumber);
301 static int m18_drv_InitialiseNAND(struct yaffs_dev *dev)
306 /* Go through the blocks formatting them if they are not formatted */
307 for(i = dev->param.start_block; i <= dev->param.end_block; i++){
308 if(!m18_drv_IsBlockFormatted(dev,i)){
309 m18_drv_FormatBlock(dev,i);
315 static int m18_drv_Deinitialise_flash_fn(struct yaffs_dev *dev)
318 m18_drv_FlashDeinit();
324 struct yaffs_dev *yaffs_m18_install_drv(const char *name)
327 struct yaffs_dev *dev = malloc(sizeof(struct yaffs_dev));
328 char *name_copy = strdup(name);
329 struct yaffs_param *param;
330 struct yaffs_driver *drv;
333 if(!dev || !name_copy) {
342 memset(dev, 0, sizeof(*dev));
344 param->name = name_copy;
346 param->total_bytes_per_chunk = 1024;
347 param->chunks_per_block =248;
348 param->n_reserved_blocks = 2;
349 param->start_block = 0; // Can use block 0
350 param->end_block = 31; // Last block
351 param->use_nand_ecc = 0; // use YAFFS's ECC
353 drv->drv_write_chunk_fn = m18_drv_WriteChunkToNAND;
354 drv->drv_read_chunk_fn = m18_drv_ReadChunkFromNAND;
355 drv->drv_erase_fn = m18_drv_EraseBlockInNAND;
356 drv->drv_initialise_fn = m18_drv_InitialiseNAND;
357 drv->drv_deinitialise_fn = m18_drv_Deinitialise_flash_fn;
359 param->n_caches = 10;
360 param->disable_soft_del = 1;
362 dev->driver_context = (void *) 1; // Used to identify the device in fstat.
364 yaffs_add_device(dev);