1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2000 Steven J. Hill (sjhill@realitydiluted.com)
4 * 2002-2006 Thomas Gleixner (tglx@linutronix.de)
5 *
6 * Credits:
7 * David Woodhouse for adding multichip support
8 *
9 * Aleph One Ltd. and Toby Churchill Ltd. for supporting the
10 * rework for 2K page size chips
11 *
12 * This file contains all ONFI helpers.
13 */
14
15 #include <linux/slab.h>
16
17 #include "internals.h"
18
19 #define ONFI_PARAM_PAGES 3
20
onfi_crc16(u16 crc,u8 const * p,size_t len)21 u16 onfi_crc16(u16 crc, u8 const *p, size_t len)
22 {
23 int i;
24 while (len--) {
25 crc ^= *p++ << 8;
26 for (i = 0; i < 8; i++)
27 crc = (crc << 1) ^ ((crc & 0x8000) ? 0x8005 : 0);
28 }
29
30 return crc;
31 }
32
33 /* Parse the Extended Parameter Page. */
nand_flash_detect_ext_param_page(struct nand_chip * chip,struct nand_onfi_params * p)34 static int nand_flash_detect_ext_param_page(struct nand_chip *chip,
35 struct nand_onfi_params *p)
36 {
37 struct nand_device *base = &chip->base;
38 struct nand_ecc_props requirements;
39 struct onfi_ext_param_page *ep;
40 struct onfi_ext_section *s;
41 struct onfi_ext_ecc_info *ecc;
42 uint8_t *cursor;
43 int ret;
44 int len;
45 int i;
46
47 len = le16_to_cpu(p->ext_param_page_length) * 16;
48 ep = kmalloc(len, GFP_KERNEL);
49 if (!ep)
50 return -ENOMEM;
51
52 /*
53 * Use the Change Read Column command to skip the ONFI param pages and
54 * ensure we read at the right location.
55 */
56 ret = nand_change_read_column_op(chip,
57 sizeof(*p) * p->num_of_param_pages,
58 ep, len, true);
59 if (ret)
60 goto ext_out;
61
62 ret = -EINVAL;
63 if ((onfi_crc16(ONFI_CRC_BASE, ((uint8_t *)ep) + 2, len - 2)
64 != le16_to_cpu(ep->crc))) {
65 pr_debug("fail in the CRC.\n");
66 goto ext_out;
67 }
68
69 /*
70 * Check the signature.
71 * Do not strictly follow the ONFI spec, maybe changed in future.
72 */
73 if (strncmp(ep->sig, "EPPS", 4)) {
74 pr_debug("The signature is invalid.\n");
75 goto ext_out;
76 }
77
78 /* find the ECC section. */
79 cursor = (uint8_t *)(ep + 1);
80 for (i = 0; i < ONFI_EXT_SECTION_MAX; i++) {
81 s = ep->sections + i;
82 if (s->type == ONFI_SECTION_TYPE_2)
83 break;
84 cursor += s->length * 16;
85 }
86 if (i == ONFI_EXT_SECTION_MAX) {
87 pr_debug("We can not find the ECC section.\n");
88 goto ext_out;
89 }
90
91 /* get the info we want. */
92 ecc = (struct onfi_ext_ecc_info *)cursor;
93
94 if (!ecc->codeword_size) {
95 pr_debug("Invalid codeword size\n");
96 goto ext_out;
97 }
98
99 requirements.strength = ecc->ecc_bits;
100 requirements.step_size = 1 << ecc->codeword_size;
101 nanddev_set_ecc_requirements(base, &requirements);
102
103 ret = 0;
104
105 ext_out:
106 kfree(ep);
107 return ret;
108 }
109
110 /*
111 * Recover data with bit-wise majority
112 */
nand_bit_wise_majority(const void ** srcbufs,unsigned int nsrcbufs,void * dstbuf,unsigned int bufsize)113 static void nand_bit_wise_majority(const void **srcbufs,
114 unsigned int nsrcbufs,
115 void *dstbuf,
116 unsigned int bufsize)
117 {
118 int i, j, k;
119
120 for (i = 0; i < bufsize; i++) {
121 u8 val = 0;
122
123 for (j = 0; j < 8; j++) {
124 unsigned int cnt = 0;
125
126 for (k = 0; k < nsrcbufs; k++) {
127 const u8 *srcbuf = srcbufs[k];
128
129 if (srcbuf[i] & BIT(j))
130 cnt++;
131 }
132
133 if (cnt > nsrcbufs / 2)
134 val |= BIT(j);
135 }
136
137 ((u8 *)dstbuf)[i] = val;
138 }
139 }
140
141 /*
142 * Check if the NAND chip is ONFI compliant, returns 1 if it is, 0 otherwise.
143 */
nand_onfi_detect(struct nand_chip * chip)144 int nand_onfi_detect(struct nand_chip *chip)
145 {
146 struct nand_device *base = &chip->base;
147 struct mtd_info *mtd = nand_to_mtd(chip);
148 struct nand_memory_organization *memorg;
149 struct nand_onfi_params *p = NULL, *pbuf;
150 struct onfi_params *onfi;
151 bool use_datain = false;
152 int onfi_version = 0;
153 char id[4];
154 int i, ret, val;
155 u16 crc;
156
157 memorg = nanddev_get_memorg(&chip->base);
158
159 /* Try ONFI for unknown chip or LP */
160 ret = nand_readid_op(chip, 0x20, id, sizeof(id));
161 if (ret || strncmp(id, "ONFI", 4))
162 return 0;
163
164 /* ONFI chip: allocate a buffer to hold its parameter page */
165 pbuf = kzalloc((sizeof(*pbuf) * ONFI_PARAM_PAGES), GFP_KERNEL);
166 if (!pbuf)
167 return -ENOMEM;
168
169 if (!nand_has_exec_op(chip) ||
170 !nand_read_data_op(chip, &pbuf[0], sizeof(*pbuf), true, true))
171 use_datain = true;
172
173 for (i = 0; i < ONFI_PARAM_PAGES; i++) {
174 if (!i)
175 ret = nand_read_param_page_op(chip, 0, &pbuf[i],
176 sizeof(*pbuf));
177 else if (use_datain)
178 ret = nand_read_data_op(chip, &pbuf[i], sizeof(*pbuf),
179 true, false);
180 else
181 ret = nand_change_read_column_op(chip, sizeof(*pbuf) * i,
182 &pbuf[i], sizeof(*pbuf),
183 true);
184 if (ret) {
185 ret = 0;
186 goto free_onfi_param_page;
187 }
188
189 crc = onfi_crc16(ONFI_CRC_BASE, (u8 *)&pbuf[i], 254);
190 if (crc == le16_to_cpu(pbuf[i].crc)) {
191 p = &pbuf[i];
192 break;
193 }
194 }
195
196 if (i == ONFI_PARAM_PAGES) {
197 const void *srcbufs[ONFI_PARAM_PAGES];
198 unsigned int j;
199
200 for (j = 0; j < ONFI_PARAM_PAGES; j++)
201 srcbufs[j] = pbuf + j;
202
203 pr_warn("Could not find a valid ONFI parameter page, trying bit-wise majority to recover it\n");
204 nand_bit_wise_majority(srcbufs, ONFI_PARAM_PAGES, pbuf,
205 sizeof(*pbuf));
206
207 crc = onfi_crc16(ONFI_CRC_BASE, (u8 *)pbuf, 254);
208 if (crc != le16_to_cpu(pbuf->crc)) {
209 pr_err("ONFI parameter recovery failed, aborting\n");
210 goto free_onfi_param_page;
211 }
212 p = pbuf;
213 }
214
215 if (chip->manufacturer.desc && chip->manufacturer.desc->ops &&
216 chip->manufacturer.desc->ops->fixup_onfi_param_page)
217 chip->manufacturer.desc->ops->fixup_onfi_param_page(chip, p);
218
219 /* Check version */
220 val = le16_to_cpu(p->revision);
221 if (val & ONFI_VERSION_2_3)
222 onfi_version = 23;
223 else if (val & ONFI_VERSION_2_2)
224 onfi_version = 22;
225 else if (val & ONFI_VERSION_2_1)
226 onfi_version = 21;
227 else if (val & ONFI_VERSION_2_0)
228 onfi_version = 20;
229 else if (val & ONFI_VERSION_1_0)
230 onfi_version = 10;
231
232 if (!onfi_version) {
233 pr_info("unsupported ONFI version: %d\n", val);
234 goto free_onfi_param_page;
235 }
236
237 sanitize_string(p->manufacturer, sizeof(p->manufacturer));
238 sanitize_string(p->model, sizeof(p->model));
239 chip->parameters.model = kstrdup(p->model, GFP_KERNEL);
240 if (!chip->parameters.model) {
241 ret = -ENOMEM;
242 goto free_onfi_param_page;
243 }
244
245 memorg->pagesize = le32_to_cpu(p->byte_per_page);
246 mtd->writesize = memorg->pagesize;
247
248 /*
249 * pages_per_block and blocks_per_lun may not be a power-of-2 size
250 * (don't ask me who thought of this...). MTD assumes that these
251 * dimensions will be power-of-2, so just truncate the remaining area.
252 */
253 memorg->pages_per_eraseblock =
254 1 << (fls(le32_to_cpu(p->pages_per_block)) - 1);
255 mtd->erasesize = memorg->pages_per_eraseblock * memorg->pagesize;
256
257 memorg->oobsize = le16_to_cpu(p->spare_bytes_per_page);
258 mtd->oobsize = memorg->oobsize;
259
260 memorg->luns_per_target = p->lun_count;
261 memorg->planes_per_lun = 1 << p->interleaved_bits;
262
263 /* See erasesize comment */
264 memorg->eraseblocks_per_lun =
265 1 << (fls(le32_to_cpu(p->blocks_per_lun)) - 1);
266 memorg->max_bad_eraseblocks_per_lun = le32_to_cpu(p->blocks_per_lun);
267 memorg->bits_per_cell = p->bits_per_cell;
268
269 if (le16_to_cpu(p->features) & ONFI_FEATURE_16_BIT_BUS)
270 chip->options |= NAND_BUSWIDTH_16;
271
272 if (p->ecc_bits != 0xff) {
273 struct nand_ecc_props requirements = {
274 .strength = p->ecc_bits,
275 .step_size = 512,
276 };
277
278 nanddev_set_ecc_requirements(base, &requirements);
279 } else if (onfi_version >= 21 &&
280 (le16_to_cpu(p->features) & ONFI_FEATURE_EXT_PARAM_PAGE)) {
281
282 /*
283 * The nand_flash_detect_ext_param_page() uses the
284 * Change Read Column command which maybe not supported
285 * by the chip->legacy.cmdfunc. So try to update the
286 * chip->legacy.cmdfunc now. We do not replace user supplied
287 * command function.
288 */
289 nand_legacy_adjust_cmdfunc(chip);
290
291 /* The Extended Parameter Page is supported since ONFI 2.1. */
292 if (nand_flash_detect_ext_param_page(chip, p))
293 pr_warn("Failed to detect ONFI extended param page\n");
294 } else {
295 pr_warn("Could not retrieve ONFI ECC requirements\n");
296 }
297
298 /* Save some parameters from the parameter page for future use */
299 if (le16_to_cpu(p->opt_cmd) & ONFI_OPT_CMD_SET_GET_FEATURES) {
300 chip->parameters.supports_set_get_features = true;
301 bitmap_set(chip->parameters.get_feature_list,
302 ONFI_FEATURE_ADDR_TIMING_MODE, 1);
303 bitmap_set(chip->parameters.set_feature_list,
304 ONFI_FEATURE_ADDR_TIMING_MODE, 1);
305 }
306
307 onfi = kzalloc(sizeof(*onfi), GFP_KERNEL);
308 if (!onfi) {
309 ret = -ENOMEM;
310 goto free_model;
311 }
312
313 onfi->version = onfi_version;
314 onfi->tPROG = le16_to_cpu(p->t_prog);
315 onfi->tBERS = le16_to_cpu(p->t_bers);
316 onfi->tR = le16_to_cpu(p->t_r);
317 onfi->tCCS = le16_to_cpu(p->t_ccs);
318 onfi->async_timing_mode = le16_to_cpu(p->async_timing_mode);
319 onfi->vendor_revision = le16_to_cpu(p->vendor_revision);
320 memcpy(onfi->vendor, p->vendor, sizeof(p->vendor));
321 chip->parameters.onfi = onfi;
322
323 /* Identification done, free the full ONFI parameter page and exit */
324 kfree(pbuf);
325
326 return 1;
327
328 free_model:
329 kfree(chip->parameters.model);
330 free_onfi_param_page:
331 kfree(pbuf);
332
333 return ret;
334 }
335