1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
|
/*
* (C) Copyright 2007-2008
* Stelian Pop <stelian@popies.net>
* Lead Tech Design <www.leadtechdesign.com>
*
* (C) Copyright 2006 ATMEL Rousset, Lacressonniere Nicolas
*
* See file CREDITS for list of people who contributed to this
* project.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
#include <common.h>
#include <asm/arch/hardware.h>
#include <asm/arch/gpio.h>
#include <asm/arch/at91_pio.h>
#include <nand.h>
#ifdef CONFIG_ATMEL_NAND_HWECC
/* Register access macros */
#define ecc_readl(add, reg) \
readl(AT91_BASE_SYS + add + ATMEL_ECC_##reg)
#define ecc_writel(add, reg, value) \
writel((value), AT91_BASE_SYS + add + ATMEL_ECC_##reg)
#include "atmel_nand_ecc.h" /* Hardware ECC registers */
/* oob layout for large page size
* bad block info is on bytes 0 and 1
* the bytes have to be consecutives to avoid
* several NAND_CMD_RNDOUT during read
*/
static struct nand_ecclayout atmel_oobinfo_large = {
.eccbytes = 4,
.eccpos = {60, 61, 62, 63},
.oobfree = {
{2, 58}
},
};
/* oob layout for small page size
* bad block info is on bytes 4 and 5
* the bytes have to be consecutives to avoid
* several NAND_CMD_RNDOUT during read
*/
static struct nand_ecclayout atmel_oobinfo_small = {
.eccbytes = 4,
.eccpos = {0, 1, 2, 3},
.oobfree = {
{6, 10}
},
};
/*
* Calculate HW ECC
*
* function called after a write
*
* mtd: MTD block structure
* dat: raw data (unused)
* ecc_code: buffer for ECC
*/
static int atmel_nand_calculate(struct mtd_info *mtd,
const u_char *dat, unsigned char *ecc_code)
{
struct nand_chip *nand_chip = mtd->priv;
unsigned int ecc_value;
/* get the first 2 ECC bytes */
ecc_value = ecc_readl(CONFIG_SYS_NAND_ECC_BASE, PR);
ecc_code[0] = ecc_value & 0xFF;
ecc_code[1] = (ecc_value >> 8) & 0xFF;
/* get the last 2 ECC bytes */
ecc_value = ecc_readl(CONFIG_SYS_NAND_ECC_BASE, NPR) & ATMEL_ECC_NPARITY;
ecc_code[2] = ecc_value & 0xFF;
ecc_code[3] = (ecc_value >> 8) & 0xFF;
return 0;
}
/*
* HW ECC read page function
*
* mtd: mtd info structure
* chip: nand chip info structure
* buf: buffer to store read data
*/
static int atmel_nand_read_page(struct mtd_info *mtd,
struct nand_chip *chip, uint8_t *buf, int page)
{
int eccsize = chip->ecc.size;
int eccbytes = chip->ecc.bytes;
uint32_t *eccpos = chip->ecc.layout->eccpos;
uint8_t *p = buf;
uint8_t *oob = chip->oob_poi;
uint8_t *ecc_pos;
int stat;
/* read the page */
chip->read_buf(mtd, p, eccsize);
/* move to ECC position if needed */
if (eccpos[0] != 0) {
/* This only works on large pages
* because the ECC controller waits for
* NAND_CMD_RNDOUTSTART after the
* NAND_CMD_RNDOUT.
* anyway, for small pages, the eccpos[0] == 0
*/
chip->cmdfunc(mtd, NAND_CMD_RNDOUT,
mtd->writesize + eccpos[0], -1);
}
/* the ECC controller needs to read the ECC just after the data */
ecc_pos = oob + eccpos[0];
chip->read_buf(mtd, ecc_pos, eccbytes);
/* check if there's an error */
stat = chip->ecc.correct(mtd, p, oob, NULL);
if (stat < 0)
mtd->ecc_stats.failed++;
else
mtd->ecc_stats.corrected += stat;
/* get back to oob start (end of page) */
chip->cmdfunc(mtd, NAND_CMD_RNDOUT, mtd->writesize, -1);
/* read the oob */
chip->read_buf(mtd, oob, mtd->oobsize);
return 0;
}
/*
* HW ECC Correction
*
* function called after a read
*
* mtd: MTD block structure
* dat: raw data read from the chip
* read_ecc: ECC from the chip (unused)
* isnull: unused
*
* Detect and correct a 1 bit error for a page
*/
static int atmel_nand_correct(struct mtd_info *mtd, u_char *dat,
u_char *read_ecc, u_char *isnull)
{
struct nand_chip *nand_chip = mtd->priv;
unsigned int ecc_status, ecc_parity, ecc_mode;
unsigned int ecc_word, ecc_bit;
/* get the status from the Status Register */
ecc_status = ecc_readl(CONFIG_SYS_NAND_ECC_BASE, SR);
/* if there's no error */
if (likely(!(ecc_status & ATMEL_ECC_RECERR)))
return 0;
/* get error bit offset (4 bits) */
ecc_bit = ecc_readl(CONFIG_SYS_NAND_ECC_BASE, PR) & ATMEL_ECC_BITADDR;
/* get word address (12 bits) */
ecc_word = ecc_readl(CONFIG_SYS_NAND_ECC_BASE, PR) & ATMEL_ECC_WORDADDR;
ecc_word >>= 4;
/* if there are multiple errors */
if (ecc_status & ATMEL_ECC_MULERR) {
/* check if it is a freshly erased block
* (filled with 0xff) */
if ((ecc_bit == ATMEL_ECC_BITADDR)
&& (ecc_word == (ATMEL_ECC_WORDADDR >> 4))) {
/* the block has just been erased, return OK */
return 0;
}
/* it doesn't seems to be a freshly
* erased block.
* We can't correct so many errors */
printk(KERN_WARNING "atmel_nand : multiple errors detected."
" Unable to correct.\n");
return -EIO;
}
/* if there's a single bit error : we can correct it */
if (ecc_status & ATMEL_ECC_ECCERR) {
/* there's nothing much to do here.
* the bit error is on the ECC itself.
*/
printk(KERN_WARNING "atmel_nand : one bit error on ECC code."
" Nothing to correct\n");
return 0;
}
printk(KERN_WARNING "atmel_nand : one bit error on data."
" (word offset in the page :"
" 0x%x bit offset : 0x%x)\n",
ecc_word, ecc_bit);
/* correct the error */
if (nand_chip->options & NAND_BUSWIDTH_16) {
/* 16 bits words */
((unsigned short *) dat)[ecc_word] ^= (1 << ecc_bit);
} else {
/* 8 bits words */
dat[ecc_word] ^= (1 << ecc_bit);
}
printk(KERN_WARNING "atmel_nand : error corrected\n");
return 1;
}
/*
* Enable HW ECC : unused on most chips
*/
static void atmel_nand_hwctl(struct mtd_info *mtd, int mode)
{
}
#endif
static void at91_nand_hwcontrol(struct mtd_info *mtd,
int cmd, unsigned int ctrl)
{
struct nand_chip *this = mtd->priv;
if (ctrl & NAND_CTRL_CHANGE) {
ulong IO_ADDR_W = (ulong) this->IO_ADDR_W;
IO_ADDR_W &= ~(CONFIG_SYS_NAND_MASK_ALE
| CONFIG_SYS_NAND_MASK_CLE);
if (ctrl & NAND_CLE)
IO_ADDR_W |= CONFIG_SYS_NAND_MASK_CLE;
if (ctrl & NAND_ALE)
IO_ADDR_W |= CONFIG_SYS_NAND_MASK_ALE;
#ifdef CONFIG_SYS_NAND_ENABLE_PIN
at91_set_gpio_value(CONFIG_SYS_NAND_ENABLE_PIN,
!(ctrl & NAND_NCE));
#endif
this->IO_ADDR_W = (void *) IO_ADDR_W;
}
if (cmd != NAND_CMD_NONE)
writeb(cmd, this->IO_ADDR_W);
}
#ifdef CONFIG_SYS_NAND_READY_PIN
static int at91_nand_ready(struct mtd_info *mtd)
{
return at91_get_gpio_value(CONFIG_SYS_NAND_READY_PIN);
}
#endif
int board_nand_init(struct nand_chip *nand)
{
#ifdef CONFIG_ATMEL_NAND_HWECC
static int chip_nr = 0;
struct mtd_info *mtd;
#endif
nand->ecc.mode = NAND_ECC_SOFT;
#ifdef CONFIG_SYS_NAND_DBW_16
nand->options = NAND_BUSWIDTH_16;
#endif
nand->cmd_ctrl = at91_nand_hwcontrol;
#ifdef CONFIG_SYS_NAND_READY_PIN
nand->dev_ready = at91_nand_ready;
#endif
nand->chip_delay = 20;
#ifdef CONFIG_ATMEL_NAND_HWECC
nand->ecc.mode = NAND_ECC_HW;
nand->ecc.calculate = atmel_nand_calculate;
nand->ecc.correct = atmel_nand_correct;
nand->ecc.hwctl = atmel_nand_hwctl;
nand->ecc.read_page = atmel_nand_read_page;
nand->ecc.bytes = 4;
#endif
#ifdef CONFIG_ATMEL_NAND_HWECC
mtd = &nand_info[chip_nr++];
mtd->priv = nand;
/* Detect NAND chips */
if (nand_scan_ident(mtd, 1, NULL)) {
printk(KERN_WARNING "NAND Flash not found !\n");
return -ENXIO;
}
if (nand->ecc.mode == NAND_ECC_HW) {
/* ECC is calculated for the whole page (1 step) */
nand->ecc.size = mtd->writesize;
/* set ECC page size and oob layout */
switch (mtd->writesize) {
case 512:
nand->ecc.layout = &atmel_oobinfo_small;
ecc_writel(CONFIG_SYS_NAND_ECC_BASE, MR, ATMEL_ECC_PAGESIZE_528);
break;
case 1024:
nand->ecc.layout = &atmel_oobinfo_large;
ecc_writel(CONFIG_SYS_NAND_ECC_BASE, MR, ATMEL_ECC_PAGESIZE_1056);
break;
case 2048:
nand->ecc.layout = &atmel_oobinfo_large;
ecc_writel(CONFIG_SYS_NAND_ECC_BASE, MR, ATMEL_ECC_PAGESIZE_2112);
break;
case 4096:
nand->ecc.layout = &atmel_oobinfo_large;
ecc_writel(CONFIG_SYS_NAND_ECC_BASE, MR, ATMEL_ECC_PAGESIZE_4224);
break;
default:
/* page size not handled by HW ECC */
/* switching back to soft ECC */
nand->ecc.mode = NAND_ECC_SOFT;
nand->ecc.calculate = NULL;
nand->ecc.correct = NULL;
nand->ecc.hwctl = NULL;
nand->ecc.read_page = NULL;
nand->ecc.postpad = 0;
nand->ecc.prepad = 0;
nand->ecc.bytes = 0;
break;
}
}
#endif
return 0;
}
|
