aboutsummaryrefslogtreecommitdiff
path: root/drivers/mtd/nand/bcm_umi_bch.c
blob: 5914bb32e0014e189cd42aafd34017698222dd27 (plain)
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
/*****************************************************************************
* Copyright 2004 - 2009 Broadcom Corporation.  All rights reserved.
*
* Unless you and Broadcom execute a separate written software license
* agreement governing use of this software, this software is licensed to you
* under the terms of the GNU General Public License version 2, available at
* http://www.broadcom.com/licenses/GPLv2.php (the "GPL").
*
* Notwithstanding the above, under no circumstances may you combine this
* software in any way with any other Broadcom software provided under a
* license other than the GPL, without Broadcom's express prior written
* consent.
*****************************************************************************/

/* ---- Include Files ---------------------------------------------------- */
#include "nand_bcm_umi.h"

/* ---- External Variable Declarations ----------------------------------- */
/* ---- External Function Prototypes ------------------------------------- */
/* ---- Public Variables ------------------------------------------------- */
/* ---- Private Constants and Types -------------------------------------- */

/* ---- Private Function Prototypes -------------------------------------- */
static int bcm_umi_bch_read_page_hwecc(struct mtd_info *mtd,
	struct nand_chip *chip, uint8_t *buf, int oob_required, int page);
static void bcm_umi_bch_write_page_hwecc(struct mtd_info *mtd,
	struct nand_chip *chip, const uint8_t *buf, int oob_required);

/* ---- Private Variables ------------------------------------------------ */

/*
** nand_hw_eccoob
** New oob placement block for use with hardware ecc generation.
*/
static struct nand_ecclayout nand_hw_eccoob_512 = {
	/* Reserve 5 for BI indicator */
	.oobfree = {
#if (NAND_ECC_NUM_BYTES > 3)
		    {.offset = 0, .length = 2}
#else
		    {.offset = 0, .length = 5},
		    {.offset = 6, .length = 7}
#endif
		    }
};

/*
** We treat the OOB for a 2K page as if it were 4 512 byte oobs,
** except the BI is at byte 0.
*/
static struct nand_ecclayout nand_hw_eccoob_2048 = {
	/* Reserve 0 as BI indicator */
	.oobfree = {
#if (NAND_ECC_NUM_BYTES > 10)
		    {.offset = 1, .length = 2},
#elif (NAND_ECC_NUM_BYTES > 7)
		    {.offset = 1, .length = 5},
		    {.offset = 16, .length = 6},
		    {.offset = 32, .length = 6},
		    {.offset = 48, .length = 6}
#else
		    {.offset = 1, .length = 8},
		    {.offset = 16, .length = 9},
		    {.offset = 32, .length = 9},
		    {.offset = 48, .length = 9}
#endif
		    }
};

/* We treat the OOB for a 4K page as if it were 8 512 byte oobs,
 * except the BI is at byte 0. */
static struct nand_ecclayout nand_hw_eccoob_4096 = {
	/* Reserve 0 as BI indicator */
	.oobfree = {
#if (NAND_ECC_NUM_BYTES > 10)
		    {.offset = 1, .length = 2},
		    {.offset = 16, .length = 3},
		    {.offset = 32, .length = 3},
		    {.offset = 48, .length = 3},
		    {.offset = 64, .length = 3},
		    {.offset = 80, .length = 3},
		    {.offset = 96, .length = 3},
		    {.offset = 112, .length = 3}
#else
		    {.offset = 1, .length = 5},
		    {.offset = 16, .length = 6},
		    {.offset = 32, .length = 6},
		    {.offset = 48, .length = 6},
		    {.offset = 64, .length = 6},
		    {.offset = 80, .length = 6},
		    {.offset = 96, .length = 6},
		    {.offset = 112, .length = 6}
#endif
		    }
};

/* ---- Private Functions ------------------------------------------------ */
/* ==== Public Functions ================================================= */

/****************************************************************************
*
*  bcm_umi_bch_read_page_hwecc - hardware ecc based page read function
*  @mtd:	mtd info structure
*  @chip:	nand chip info structure
*  @buf:	buffer to store read data
*  @oob_required:	caller expects OOB data read to chip->oob_poi
*
***************************************************************************/
static int bcm_umi_bch_read_page_hwecc(struct mtd_info *mtd,
				       struct nand_chip *chip, uint8_t * buf,
				       int oob_required, int page)
{
	int sectorIdx = 0;
	int eccsize = chip->ecc.size;
	int eccsteps = chip->ecc.steps;
	uint8_t *datap = buf;
	uint8_t eccCalc[NAND_ECC_NUM_BYTES];
	int sectorOobSize = mtd->oobsize / eccsteps;
	int stat;
	unsigned int max_bitflips = 0;

	for (sectorIdx = 0; sectorIdx < eccsteps;
			sectorIdx++, datap += eccsize) {
		if (sectorIdx > 0) {
			/* Seek to page location within sector */
			chip->cmdfunc(mtd, NAND_CMD_RNDOUT, sectorIdx * eccsize,
				      -1);
		}

		/* Enable hardware ECC before reading the buf */
		nand_bcm_umi_bch_enable_read_hwecc();

		/* Read in data */
		bcm_umi_nand_read_buf(mtd, datap, eccsize);

		/* Pause hardware ECC after reading the buf */
		nand_bcm_umi_bch_pause_read_ecc_calc();

		/* Read the OOB ECC */
		chip->cmdfunc(mtd, NAND_CMD_RNDOUT,
			      mtd->writesize + sectorIdx * sectorOobSize, -1);
		nand_bcm_umi_bch_read_oobEcc(mtd->writesize, eccCalc,
					     NAND_ECC_NUM_BYTES,
					     chip->oob_poi +
					     sectorIdx * sectorOobSize);

		/* Correct any ECC detected errors */
		stat =
		    nand_bcm_umi_bch_correct_page(datap, eccCalc,
						  NAND_ECC_NUM_BYTES);

		/* Update Stats */
		if (stat < 0) {
#if defined(NAND_BCM_UMI_DEBUG)
			printk(KERN_WARNING "%s uncorr_err sectorIdx=%d\n",
			       __func__, sectorIdx);
			printk(KERN_WARNING
			       "%s data %02x %02x %02x %02x "
					 "%02x %02x %02x %02x\n",
			       __func__, datap[0], datap[1], datap[2], datap[3],
			       datap[4], datap[5], datap[6], datap[7]);
			printk(KERN_WARNING
			       "%s ecc  %02x %02x %02x %02x "
					 "%02x %02x %02x %02x %02x %02x "
					 "%02x %02x %02x\n",
			       __func__, eccCalc[0], eccCalc[1], eccCalc[2],
			       eccCalc[3], eccCalc[4], eccCalc[5], eccCalc[6],
			       eccCalc[7], eccCalc[8], eccCalc[9], eccCalc[10],
			       eccCalc[11], eccCalc[12]);
			BUG();
#endif
			mtd->ecc_stats.failed++;
		} else {
#if defined(NAND_BCM_UMI_DEBUG)
			if (stat > 0) {
				printk(KERN_INFO
				       "%s %d correctable_errors detected\n",
				       __func__, stat);
			}
#endif
			mtd->ecc_stats.corrected += stat;
			max_bitflips = max_t(unsigned int, max_bitflips, stat);
		}
	}
	return max_bitflips;
}

/****************************************************************************
*
*  bcm_umi_bch_write_page_hwecc - hardware ecc based page write function
*  @mtd:	mtd info structure
*  @chip:	nand chip info structure
*  @buf:	data buffer
*  @oob_required:	must write chip->oob_poi to OOB
*
***************************************************************************/
static void bcm_umi_bch_write_page_hwecc(struct mtd_info *mtd,
	struct nand_chip *chip, const uint8_t *buf, int oob_required)
{
	int sectorIdx = 0;
	int eccsize = chip->ecc.size;
	int eccsteps = chip->ecc.steps;
	const uint8_t *datap = buf;
	uint8_t *oobp = chip->oob_poi;
	int sectorOobSize = mtd->oobsize / eccsteps;

	for (sectorIdx = 0; sectorIdx < eccsteps;
	     sectorIdx++, datap += eccsize, oobp += sectorOobSize) {
		/* Enable hardware ECC before writing the buf */
		nand_bcm_umi_bch_enable_write_hwecc();
		bcm_umi_nand_write_buf(mtd, datap, eccsize);
		nand_bcm_umi_bch_write_oobEcc(mtd->writesize, oobp,
					      NAND_ECC_NUM_BYTES);
	}

	bcm_umi_nand_write_buf(mtd, chip->oob_poi, mtd->oobsize);
}