1 /*
2 * Copyright © 2004 Texas Instruments, Jian Zhang <jzhang@ti.com>
3 * Copyright © 2004 Micron Technology Inc.
4 * Copyright © 2004 David Brownell
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10
11 #include <linux/platform_device.h>
12 #include <linux/dmaengine.h>
13 #include <linux/dma-mapping.h>
14 #include <linux/delay.h>
15 #include <linux/module.h>
16 #include <linux/interrupt.h>
17 #include <linux/jiffies.h>
18 #include <linux/sched.h>
19 #include <linux/mtd/mtd.h>
20 #include <linux/mtd/nand.h>
21 #include <linux/mtd/partitions.h>
22 #include <linux/omap-dma.h>
23 #include <linux/io.h>
24 #include <linux/slab.h>
25 #include <linux/of.h>
26 #include <linux/of_device.h>
27
28 #ifdef CONFIG_MTD_NAND_OMAP_BCH
29 #include <linux/bch.h>
30 #include <linux/platform_data/elm.h>
31 #endif
32
33 #include <linux/platform_data/mtd-nand-omap2.h>
34
35 #define DRIVER_NAME "omap2-nand"
36 #define OMAP_NAND_TIMEOUT_MS 5000
37
38 #define NAND_Ecc_P1e (1 << 0)
39 #define NAND_Ecc_P2e (1 << 1)
40 #define NAND_Ecc_P4e (1 << 2)
41 #define NAND_Ecc_P8e (1 << 3)
42 #define NAND_Ecc_P16e (1 << 4)
43 #define NAND_Ecc_P32e (1 << 5)
44 #define NAND_Ecc_P64e (1 << 6)
45 #define NAND_Ecc_P128e (1 << 7)
46 #define NAND_Ecc_P256e (1 << 8)
47 #define NAND_Ecc_P512e (1 << 9)
48 #define NAND_Ecc_P1024e (1 << 10)
49 #define NAND_Ecc_P2048e (1 << 11)
50
51 #define NAND_Ecc_P1o (1 << 16)
52 #define NAND_Ecc_P2o (1 << 17)
53 #define NAND_Ecc_P4o (1 << 18)
54 #define NAND_Ecc_P8o (1 << 19)
55 #define NAND_Ecc_P16o (1 << 20)
56 #define NAND_Ecc_P32o (1 << 21)
57 #define NAND_Ecc_P64o (1 << 22)
58 #define NAND_Ecc_P128o (1 << 23)
59 #define NAND_Ecc_P256o (1 << 24)
60 #define NAND_Ecc_P512o (1 << 25)
61 #define NAND_Ecc_P1024o (1 << 26)
62 #define NAND_Ecc_P2048o (1 << 27)
63
64 #define TF(value) (value ? 1 : 0)
65
66 #define P2048e(a) (TF(a & NAND_Ecc_P2048e) << 0)
67 #define P2048o(a) (TF(a & NAND_Ecc_P2048o) << 1)
68 #define P1e(a) (TF(a & NAND_Ecc_P1e) << 2)
69 #define P1o(a) (TF(a & NAND_Ecc_P1o) << 3)
70 #define P2e(a) (TF(a & NAND_Ecc_P2e) << 4)
71 #define P2o(a) (TF(a & NAND_Ecc_P2o) << 5)
72 #define P4e(a) (TF(a & NAND_Ecc_P4e) << 6)
73 #define P4o(a) (TF(a & NAND_Ecc_P4o) << 7)
74
75 #define P8e(a) (TF(a & NAND_Ecc_P8e) << 0)
76 #define P8o(a) (TF(a & NAND_Ecc_P8o) << 1)
77 #define P16e(a) (TF(a & NAND_Ecc_P16e) << 2)
78 #define P16o(a) (TF(a & NAND_Ecc_P16o) << 3)
79 #define P32e(a) (TF(a & NAND_Ecc_P32e) << 4)
80 #define P32o(a) (TF(a & NAND_Ecc_P32o) << 5)
81 #define P64e(a) (TF(a & NAND_Ecc_P64e) << 6)
82 #define P64o(a) (TF(a & NAND_Ecc_P64o) << 7)
83
84 #define P128e(a) (TF(a & NAND_Ecc_P128e) << 0)
85 #define P128o(a) (TF(a & NAND_Ecc_P128o) << 1)
86 #define P256e(a) (TF(a & NAND_Ecc_P256e) << 2)
87 #define P256o(a) (TF(a & NAND_Ecc_P256o) << 3)
88 #define P512e(a) (TF(a & NAND_Ecc_P512e) << 4)
89 #define P512o(a) (TF(a & NAND_Ecc_P512o) << 5)
90 #define P1024e(a) (TF(a & NAND_Ecc_P1024e) << 6)
91 #define P1024o(a) (TF(a & NAND_Ecc_P1024o) << 7)
92
93 #define P8e_s(a) (TF(a & NAND_Ecc_P8e) << 0)
94 #define P8o_s(a) (TF(a & NAND_Ecc_P8o) << 1)
95 #define P16e_s(a) (TF(a & NAND_Ecc_P16e) << 2)
96 #define P16o_s(a) (TF(a & NAND_Ecc_P16o) << 3)
97 #define P1e_s(a) (TF(a & NAND_Ecc_P1e) << 4)
98 #define P1o_s(a) (TF(a & NAND_Ecc_P1o) << 5)
99 #define P2e_s(a) (TF(a & NAND_Ecc_P2e) << 6)
100 #define P2o_s(a) (TF(a & NAND_Ecc_P2o) << 7)
101
102 #define P4e_s(a) (TF(a & NAND_Ecc_P4e) << 0)
103 #define P4o_s(a) (TF(a & NAND_Ecc_P4o) << 1)
104
105 #define PREFETCH_CONFIG1_CS_SHIFT 24
106 #define ECC_CONFIG_CS_SHIFT 1
107 #define CS_MASK 0x7
108 #define ENABLE_PREFETCH (0x1 << 7)
109 #define DMA_MPU_MODE_SHIFT 2
110 #define ECCSIZE0_SHIFT 12
111 #define ECCSIZE1_SHIFT 22
112 #define ECC1RESULTSIZE 0x1
113 #define ECCCLEAR 0x100
114 #define ECC1 0x1
115 #define PREFETCH_FIFOTHRESHOLD_MAX 0x40
116 #define PREFETCH_FIFOTHRESHOLD(val) ((val) << 8)
117 #define PREFETCH_STATUS_COUNT(val) (val & 0x00003fff)
118 #define PREFETCH_STATUS_FIFO_CNT(val) ((val >> 24) & 0x7F)
119 #define STATUS_BUFF_EMPTY 0x00000001
120
121 #define OMAP24XX_DMA_GPMC 4
122
123 #define BCH8_MAX_ERROR 8 /* upto 8 bit correctable */
124 #define BCH4_MAX_ERROR 4 /* upto 4 bit correctable */
125
126 #define SECTOR_BYTES 512
127 /* 4 bit padding to make byte aligned, 56 = 52 + 4 */
128 #define BCH4_BIT_PAD 4
129 #define BCH8_ECC_MAX ((SECTOR_BYTES + BCH8_ECC_OOB_BYTES) * 8)
130 #define BCH4_ECC_MAX ((SECTOR_BYTES + BCH4_ECC_OOB_BYTES) * 8)
131
132 /* GPMC ecc engine settings for read */
133 #define BCH_WRAPMODE_1 1 /* BCH wrap mode 1 */
134 #define BCH8R_ECC_SIZE0 0x1a /* ecc_size0 = 26 */
135 #define BCH8R_ECC_SIZE1 0x2 /* ecc_size1 = 2 */
136 #define BCH4R_ECC_SIZE0 0xd /* ecc_size0 = 13 */
137 #define BCH4R_ECC_SIZE1 0x3 /* ecc_size1 = 3 */
138
139 /* GPMC ecc engine settings for write */
140 #define BCH_WRAPMODE_6 6 /* BCH wrap mode 6 */
141 #define BCH_ECC_SIZE0 0x0 /* ecc_size0 = 0, no oob protection */
142 #define BCH_ECC_SIZE1 0x20 /* ecc_size1 = 32 */
143
144 #ifdef CONFIG_MTD_NAND_OMAP_BCH
145 static u_char bch8_vector[] = {0xf3, 0xdb, 0x14, 0x16, 0x8b, 0xd2, 0xbe, 0xcc,
146 0xac, 0x6b, 0xff, 0x99, 0x7b};
147 static u_char bch4_vector[] = {0x00, 0x6b, 0x31, 0xdd, 0x41, 0xbc, 0x10};
148 #endif
149
150 /* oob info generated runtime depending on ecc algorithm and layout selected */
151 static struct nand_ecclayout omap_oobinfo;
152 /* Define some generic bad / good block scan pattern which are used
153 * while scanning a device for factory marked good / bad blocks
154 */
155 static uint8_t scan_ff_pattern[] = { 0xff };
156 static struct nand_bbt_descr bb_descrip_flashbased = {
157 .options = NAND_BBT_SCANEMPTY | NAND_BBT_SCANALLPAGES,
158 .offs = 0,
159 .len = 1,
160 .pattern = scan_ff_pattern,
161 };
162
163
164 struct omap_nand_info {
165 struct nand_hw_control controller;
166 struct omap_nand_platform_data *pdata;
167 struct mtd_info mtd;
168 struct nand_chip nand;
169 struct platform_device *pdev;
170
171 int gpmc_cs;
172 unsigned long phys_base;
173 unsigned long mem_size;
174 struct completion comp;
175 struct dma_chan *dma;
176 int gpmc_irq_fifo;
177 int gpmc_irq_count;
178 enum {
179 OMAP_NAND_IO_READ = 0, /* read */
180 OMAP_NAND_IO_WRITE, /* write */
181 } iomode;
182 u_char *buf;
183 int buf_len;
184 struct gpmc_nand_regs reg;
185
186 #ifdef CONFIG_MTD_NAND_OMAP_BCH
187 struct bch_control *bch;
188 struct nand_ecclayout ecclayout;
189 bool is_elm_used;
190 struct device *elm_dev;
191 struct device_node *of_node;
192 #endif
193 };
194
195 /**
196 * omap_prefetch_enable - configures and starts prefetch transfer
197 * @cs: cs (chip select) number
198 * @fifo_th: fifo threshold to be used for read/ write
199 * @dma_mode: dma mode enable (1) or disable (0)
200 * @u32_count: number of bytes to be transferred
201 * @is_write: prefetch read(0) or write post(1) mode
202 */
omap_prefetch_enable(int cs,int fifo_th,int dma_mode,unsigned int u32_count,int is_write,struct omap_nand_info * info)203 static int omap_prefetch_enable(int cs, int fifo_th, int dma_mode,
204 unsigned int u32_count, int is_write, struct omap_nand_info *info)
205 {
206 u32 val;
207
208 if (fifo_th > PREFETCH_FIFOTHRESHOLD_MAX)
209 return -1;
210
211 if (readl(info->reg.gpmc_prefetch_control))
212 return -EBUSY;
213
214 /* Set the amount of bytes to be prefetched */
215 writel(u32_count, info->reg.gpmc_prefetch_config2);
216
217 /* Set dma/mpu mode, the prefetch read / post write and
218 * enable the engine. Set which cs is has requested for.
219 */
220 val = ((cs << PREFETCH_CONFIG1_CS_SHIFT) |
221 PREFETCH_FIFOTHRESHOLD(fifo_th) | ENABLE_PREFETCH |
222 (dma_mode << DMA_MPU_MODE_SHIFT) | (0x1 & is_write));
223 writel(val, info->reg.gpmc_prefetch_config1);
224
225 /* Start the prefetch engine */
226 writel(0x1, info->reg.gpmc_prefetch_control);
227
228 return 0;
229 }
230
231 /**
232 * omap_prefetch_reset - disables and stops the prefetch engine
233 */
omap_prefetch_reset(int cs,struct omap_nand_info * info)234 static int omap_prefetch_reset(int cs, struct omap_nand_info *info)
235 {
236 u32 config1;
237
238 /* check if the same module/cs is trying to reset */
239 config1 = readl(info->reg.gpmc_prefetch_config1);
240 if (((config1 >> PREFETCH_CONFIG1_CS_SHIFT) & CS_MASK) != cs)
241 return -EINVAL;
242
243 /* Stop the PFPW engine */
244 writel(0x0, info->reg.gpmc_prefetch_control);
245
246 /* Reset/disable the PFPW engine */
247 writel(0x0, info->reg.gpmc_prefetch_config1);
248
249 return 0;
250 }
251
252 /**
253 * omap_hwcontrol - hardware specific access to control-lines
254 * @mtd: MTD device structure
255 * @cmd: command to device
256 * @ctrl:
257 * NAND_NCE: bit 0 -> don't care
258 * NAND_CLE: bit 1 -> Command Latch
259 * NAND_ALE: bit 2 -> Address Latch
260 *
261 * NOTE: boards may use different bits for these!!
262 */
omap_hwcontrol(struct mtd_info * mtd,int cmd,unsigned int ctrl)263 static void omap_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int ctrl)
264 {
265 struct omap_nand_info *info = container_of(mtd,
266 struct omap_nand_info, mtd);
267
268 if (cmd != NAND_CMD_NONE) {
269 if (ctrl & NAND_CLE)
270 writeb(cmd, info->reg.gpmc_nand_command);
271
272 else if (ctrl & NAND_ALE)
273 writeb(cmd, info->reg.gpmc_nand_address);
274
275 else /* NAND_NCE */
276 writeb(cmd, info->reg.gpmc_nand_data);
277 }
278 }
279
280 /**
281 * omap_read_buf8 - read data from NAND controller into buffer
282 * @mtd: MTD device structure
283 * @buf: buffer to store date
284 * @len: number of bytes to read
285 */
omap_read_buf8(struct mtd_info * mtd,u_char * buf,int len)286 static void omap_read_buf8(struct mtd_info *mtd, u_char *buf, int len)
287 {
288 struct nand_chip *nand = mtd->priv;
289
290 ioread8_rep(nand->IO_ADDR_R, buf, len);
291 }
292
293 /**
294 * omap_write_buf8 - write buffer to NAND controller
295 * @mtd: MTD device structure
296 * @buf: data buffer
297 * @len: number of bytes to write
298 */
omap_write_buf8(struct mtd_info * mtd,const u_char * buf,int len)299 static void omap_write_buf8(struct mtd_info *mtd, const u_char *buf, int len)
300 {
301 struct omap_nand_info *info = container_of(mtd,
302 struct omap_nand_info, mtd);
303 u_char *p = (u_char *)buf;
304 u32 status = 0;
305
306 while (len--) {
307 iowrite8(*p++, info->nand.IO_ADDR_W);
308 /* wait until buffer is available for write */
309 do {
310 status = readl(info->reg.gpmc_status) &
311 STATUS_BUFF_EMPTY;
312 } while (!status);
313 }
314 }
315
316 /**
317 * omap_read_buf16 - read data from NAND controller into buffer
318 * @mtd: MTD device structure
319 * @buf: buffer to store date
320 * @len: number of bytes to read
321 */
omap_read_buf16(struct mtd_info * mtd,u_char * buf,int len)322 static void omap_read_buf16(struct mtd_info *mtd, u_char *buf, int len)
323 {
324 struct nand_chip *nand = mtd->priv;
325
326 ioread16_rep(nand->IO_ADDR_R, buf, len / 2);
327 }
328
329 /**
330 * omap_write_buf16 - write buffer to NAND controller
331 * @mtd: MTD device structure
332 * @buf: data buffer
333 * @len: number of bytes to write
334 */
omap_write_buf16(struct mtd_info * mtd,const u_char * buf,int len)335 static void omap_write_buf16(struct mtd_info *mtd, const u_char * buf, int len)
336 {
337 struct omap_nand_info *info = container_of(mtd,
338 struct omap_nand_info, mtd);
339 u16 *p = (u16 *) buf;
340 u32 status = 0;
341 /* FIXME try bursts of writesw() or DMA ... */
342 len >>= 1;
343
344 while (len--) {
345 iowrite16(*p++, info->nand.IO_ADDR_W);
346 /* wait until buffer is available for write */
347 do {
348 status = readl(info->reg.gpmc_status) &
349 STATUS_BUFF_EMPTY;
350 } while (!status);
351 }
352 }
353
354 /**
355 * omap_read_buf_pref - read data from NAND controller into buffer
356 * @mtd: MTD device structure
357 * @buf: buffer to store date
358 * @len: number of bytes to read
359 */
omap_read_buf_pref(struct mtd_info * mtd,u_char * buf,int len)360 static void omap_read_buf_pref(struct mtd_info *mtd, u_char *buf, int len)
361 {
362 struct omap_nand_info *info = container_of(mtd,
363 struct omap_nand_info, mtd);
364 uint32_t r_count = 0;
365 int ret = 0;
366 u32 *p = (u32 *)buf;
367
368 /* take care of subpage reads */
369 if (len % 4) {
370 if (info->nand.options & NAND_BUSWIDTH_16)
371 omap_read_buf16(mtd, buf, len % 4);
372 else
373 omap_read_buf8(mtd, buf, len % 4);
374 p = (u32 *) (buf + len % 4);
375 len -= len % 4;
376 }
377
378 /* configure and start prefetch transfer */
379 ret = omap_prefetch_enable(info->gpmc_cs,
380 PREFETCH_FIFOTHRESHOLD_MAX, 0x0, len, 0x0, info);
381 if (ret) {
382 /* PFPW engine is busy, use cpu copy method */
383 if (info->nand.options & NAND_BUSWIDTH_16)
384 omap_read_buf16(mtd, (u_char *)p, len);
385 else
386 omap_read_buf8(mtd, (u_char *)p, len);
387 } else {
388 do {
389 r_count = readl(info->reg.gpmc_prefetch_status);
390 r_count = PREFETCH_STATUS_FIFO_CNT(r_count);
391 r_count = r_count >> 2;
392 ioread32_rep(info->nand.IO_ADDR_R, p, r_count);
393 p += r_count;
394 len -= r_count << 2;
395 } while (len);
396 /* disable and stop the PFPW engine */
397 omap_prefetch_reset(info->gpmc_cs, info);
398 }
399 }
400
401 /**
402 * omap_write_buf_pref - write buffer to NAND controller
403 * @mtd: MTD device structure
404 * @buf: data buffer
405 * @len: number of bytes to write
406 */
omap_write_buf_pref(struct mtd_info * mtd,const u_char * buf,int len)407 static void omap_write_buf_pref(struct mtd_info *mtd,
408 const u_char *buf, int len)
409 {
410 struct omap_nand_info *info = container_of(mtd,
411 struct omap_nand_info, mtd);
412 uint32_t w_count = 0;
413 int i = 0, ret = 0;
414 u16 *p = (u16 *)buf;
415 unsigned long tim, limit;
416 u32 val;
417
418 /* take care of subpage writes */
419 if (len % 2 != 0) {
420 writeb(*buf, info->nand.IO_ADDR_W);
421 p = (u16 *)(buf + 1);
422 len--;
423 }
424
425 /* configure and start prefetch transfer */
426 ret = omap_prefetch_enable(info->gpmc_cs,
427 PREFETCH_FIFOTHRESHOLD_MAX, 0x0, len, 0x1, info);
428 if (ret) {
429 /* PFPW engine is busy, use cpu copy method */
430 if (info->nand.options & NAND_BUSWIDTH_16)
431 omap_write_buf16(mtd, (u_char *)p, len);
432 else
433 omap_write_buf8(mtd, (u_char *)p, len);
434 } else {
435 while (len) {
436 w_count = readl(info->reg.gpmc_prefetch_status);
437 w_count = PREFETCH_STATUS_FIFO_CNT(w_count);
438 w_count = w_count >> 1;
439 for (i = 0; (i < w_count) && len; i++, len -= 2)
440 iowrite16(*p++, info->nand.IO_ADDR_W);
441 }
442 /* wait for data to flushed-out before reset the prefetch */
443 tim = 0;
444 limit = (loops_per_jiffy *
445 msecs_to_jiffies(OMAP_NAND_TIMEOUT_MS));
446 do {
447 cpu_relax();
448 val = readl(info->reg.gpmc_prefetch_status);
449 val = PREFETCH_STATUS_COUNT(val);
450 } while (val && (tim++ < limit));
451
452 /* disable and stop the PFPW engine */
453 omap_prefetch_reset(info->gpmc_cs, info);
454 }
455 }
456
457 /*
458 * omap_nand_dma_callback: callback on the completion of dma transfer
459 * @data: pointer to completion data structure
460 */
omap_nand_dma_callback(void * data)461 static void omap_nand_dma_callback(void *data)
462 {
463 complete((struct completion *) data);
464 }
465
466 /*
467 * omap_nand_dma_transfer: configure and start dma transfer
468 * @mtd: MTD device structure
469 * @addr: virtual address in RAM of source/destination
470 * @len: number of data bytes to be transferred
471 * @is_write: flag for read/write operation
472 */
omap_nand_dma_transfer(struct mtd_info * mtd,void * addr,unsigned int len,int is_write)473 static inline int omap_nand_dma_transfer(struct mtd_info *mtd, void *addr,
474 unsigned int len, int is_write)
475 {
476 struct omap_nand_info *info = container_of(mtd,
477 struct omap_nand_info, mtd);
478 struct dma_async_tx_descriptor *tx;
479 enum dma_data_direction dir = is_write ? DMA_TO_DEVICE :
480 DMA_FROM_DEVICE;
481 struct scatterlist sg;
482 unsigned long tim, limit;
483 unsigned n;
484 int ret;
485 u32 val;
486
487 if (addr >= high_memory) {
488 struct page *p1;
489
490 if (((size_t)addr & PAGE_MASK) !=
491 ((size_t)(addr + len - 1) & PAGE_MASK))
492 goto out_copy;
493 p1 = vmalloc_to_page(addr);
494 if (!p1)
495 goto out_copy;
496 addr = page_address(p1) + ((size_t)addr & ~PAGE_MASK);
497 }
498
499 sg_init_one(&sg, addr, len);
500 n = dma_map_sg(info->dma->device->dev, &sg, 1, dir);
501 if (n == 0) {
502 dev_err(&info->pdev->dev,
503 "Couldn't DMA map a %d byte buffer\n", len);
504 goto out_copy;
505 }
506
507 tx = dmaengine_prep_slave_sg(info->dma, &sg, n,
508 is_write ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM,
509 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
510 if (!tx)
511 goto out_copy_unmap;
512
513 tx->callback = omap_nand_dma_callback;
514 tx->callback_param = &info->comp;
515 dmaengine_submit(tx);
516
517 /* configure and start prefetch transfer */
518 ret = omap_prefetch_enable(info->gpmc_cs,
519 PREFETCH_FIFOTHRESHOLD_MAX, 0x1, len, is_write, info);
520 if (ret)
521 /* PFPW engine is busy, use cpu copy method */
522 goto out_copy_unmap;
523
524 init_completion(&info->comp);
525 dma_async_issue_pending(info->dma);
526
527 /* setup and start DMA using dma_addr */
528 wait_for_completion(&info->comp);
529 tim = 0;
530 limit = (loops_per_jiffy * msecs_to_jiffies(OMAP_NAND_TIMEOUT_MS));
531
532 do {
533 cpu_relax();
534 val = readl(info->reg.gpmc_prefetch_status);
535 val = PREFETCH_STATUS_COUNT(val);
536 } while (val && (tim++ < limit));
537
538 /* disable and stop the PFPW engine */
539 omap_prefetch_reset(info->gpmc_cs, info);
540
541 dma_unmap_sg(info->dma->device->dev, &sg, 1, dir);
542 return 0;
543
544 out_copy_unmap:
545 dma_unmap_sg(info->dma->device->dev, &sg, 1, dir);
546 out_copy:
547 if (info->nand.options & NAND_BUSWIDTH_16)
548 is_write == 0 ? omap_read_buf16(mtd, (u_char *) addr, len)
549 : omap_write_buf16(mtd, (u_char *) addr, len);
550 else
551 is_write == 0 ? omap_read_buf8(mtd, (u_char *) addr, len)
552 : omap_write_buf8(mtd, (u_char *) addr, len);
553 return 0;
554 }
555
556 /**
557 * omap_read_buf_dma_pref - read data from NAND controller into buffer
558 * @mtd: MTD device structure
559 * @buf: buffer to store date
560 * @len: number of bytes to read
561 */
omap_read_buf_dma_pref(struct mtd_info * mtd,u_char * buf,int len)562 static void omap_read_buf_dma_pref(struct mtd_info *mtd, u_char *buf, int len)
563 {
564 if (len <= mtd->oobsize)
565 omap_read_buf_pref(mtd, buf, len);
566 else
567 /* start transfer in DMA mode */
568 omap_nand_dma_transfer(mtd, buf, len, 0x0);
569 }
570
571 /**
572 * omap_write_buf_dma_pref - write buffer to NAND controller
573 * @mtd: MTD device structure
574 * @buf: data buffer
575 * @len: number of bytes to write
576 */
omap_write_buf_dma_pref(struct mtd_info * mtd,const u_char * buf,int len)577 static void omap_write_buf_dma_pref(struct mtd_info *mtd,
578 const u_char *buf, int len)
579 {
580 if (len <= mtd->oobsize)
581 omap_write_buf_pref(mtd, buf, len);
582 else
583 /* start transfer in DMA mode */
584 omap_nand_dma_transfer(mtd, (u_char *) buf, len, 0x1);
585 }
586
587 /*
588 * omap_nand_irq - GPMC irq handler
589 * @this_irq: gpmc irq number
590 * @dev: omap_nand_info structure pointer is passed here
591 */
omap_nand_irq(int this_irq,void * dev)592 static irqreturn_t omap_nand_irq(int this_irq, void *dev)
593 {
594 struct omap_nand_info *info = (struct omap_nand_info *) dev;
595 u32 bytes;
596
597 bytes = readl(info->reg.gpmc_prefetch_status);
598 bytes = PREFETCH_STATUS_FIFO_CNT(bytes);
599 bytes = bytes & 0xFFFC; /* io in multiple of 4 bytes */
600 if (info->iomode == OMAP_NAND_IO_WRITE) { /* checks for write io */
601 if (this_irq == info->gpmc_irq_count)
602 goto done;
603
604 if (info->buf_len && (info->buf_len < bytes))
605 bytes = info->buf_len;
606 else if (!info->buf_len)
607 bytes = 0;
608 iowrite32_rep(info->nand.IO_ADDR_W,
609 (u32 *)info->buf, bytes >> 2);
610 info->buf = info->buf + bytes;
611 info->buf_len -= bytes;
612
613 } else {
614 ioread32_rep(info->nand.IO_ADDR_R,
615 (u32 *)info->buf, bytes >> 2);
616 info->buf = info->buf + bytes;
617
618 if (this_irq == info->gpmc_irq_count)
619 goto done;
620 }
621
622 return IRQ_HANDLED;
623
624 done:
625 complete(&info->comp);
626
627 disable_irq_nosync(info->gpmc_irq_fifo);
628 disable_irq_nosync(info->gpmc_irq_count);
629
630 return IRQ_HANDLED;
631 }
632
633 /*
634 * omap_read_buf_irq_pref - read data from NAND controller into buffer
635 * @mtd: MTD device structure
636 * @buf: buffer to store date
637 * @len: number of bytes to read
638 */
omap_read_buf_irq_pref(struct mtd_info * mtd,u_char * buf,int len)639 static void omap_read_buf_irq_pref(struct mtd_info *mtd, u_char *buf, int len)
640 {
641 struct omap_nand_info *info = container_of(mtd,
642 struct omap_nand_info, mtd);
643 int ret = 0;
644
645 if (len <= mtd->oobsize) {
646 omap_read_buf_pref(mtd, buf, len);
647 return;
648 }
649
650 info->iomode = OMAP_NAND_IO_READ;
651 info->buf = buf;
652 init_completion(&info->comp);
653
654 /* configure and start prefetch transfer */
655 ret = omap_prefetch_enable(info->gpmc_cs,
656 PREFETCH_FIFOTHRESHOLD_MAX/2, 0x0, len, 0x0, info);
657 if (ret)
658 /* PFPW engine is busy, use cpu copy method */
659 goto out_copy;
660
661 info->buf_len = len;
662
663 enable_irq(info->gpmc_irq_count);
664 enable_irq(info->gpmc_irq_fifo);
665
666 /* waiting for read to complete */
667 wait_for_completion(&info->comp);
668
669 /* disable and stop the PFPW engine */
670 omap_prefetch_reset(info->gpmc_cs, info);
671 return;
672
673 out_copy:
674 if (info->nand.options & NAND_BUSWIDTH_16)
675 omap_read_buf16(mtd, buf, len);
676 else
677 omap_read_buf8(mtd, buf, len);
678 }
679
680 /*
681 * omap_write_buf_irq_pref - write buffer to NAND controller
682 * @mtd: MTD device structure
683 * @buf: data buffer
684 * @len: number of bytes to write
685 */
omap_write_buf_irq_pref(struct mtd_info * mtd,const u_char * buf,int len)686 static void omap_write_buf_irq_pref(struct mtd_info *mtd,
687 const u_char *buf, int len)
688 {
689 struct omap_nand_info *info = container_of(mtd,
690 struct omap_nand_info, mtd);
691 int ret = 0;
692 unsigned long tim, limit;
693 u32 val;
694
695 if (len <= mtd->oobsize) {
696 omap_write_buf_pref(mtd, buf, len);
697 return;
698 }
699
700 info->iomode = OMAP_NAND_IO_WRITE;
701 info->buf = (u_char *) buf;
702 init_completion(&info->comp);
703
704 /* configure and start prefetch transfer : size=24 */
705 ret = omap_prefetch_enable(info->gpmc_cs,
706 (PREFETCH_FIFOTHRESHOLD_MAX * 3) / 8, 0x0, len, 0x1, info);
707 if (ret)
708 /* PFPW engine is busy, use cpu copy method */
709 goto out_copy;
710
711 info->buf_len = len;
712
713 enable_irq(info->gpmc_irq_count);
714 enable_irq(info->gpmc_irq_fifo);
715
716 /* waiting for write to complete */
717 wait_for_completion(&info->comp);
718
719 /* wait for data to flushed-out before reset the prefetch */
720 tim = 0;
721 limit = (loops_per_jiffy * msecs_to_jiffies(OMAP_NAND_TIMEOUT_MS));
722 do {
723 val = readl(info->reg.gpmc_prefetch_status);
724 val = PREFETCH_STATUS_COUNT(val);
725 cpu_relax();
726 } while (val && (tim++ < limit));
727
728 /* disable and stop the PFPW engine */
729 omap_prefetch_reset(info->gpmc_cs, info);
730 return;
731
732 out_copy:
733 if (info->nand.options & NAND_BUSWIDTH_16)
734 omap_write_buf16(mtd, buf, len);
735 else
736 omap_write_buf8(mtd, buf, len);
737 }
738
739 /**
740 * gen_true_ecc - This function will generate true ECC value
741 * @ecc_buf: buffer to store ecc code
742 *
743 * This generated true ECC value can be used when correcting
744 * data read from NAND flash memory core
745 */
gen_true_ecc(u8 * ecc_buf)746 static void gen_true_ecc(u8 *ecc_buf)
747 {
748 u32 tmp = ecc_buf[0] | (ecc_buf[1] << 16) |
749 ((ecc_buf[2] & 0xF0) << 20) | ((ecc_buf[2] & 0x0F) << 8);
750
751 ecc_buf[0] = ~(P64o(tmp) | P64e(tmp) | P32o(tmp) | P32e(tmp) |
752 P16o(tmp) | P16e(tmp) | P8o(tmp) | P8e(tmp));
753 ecc_buf[1] = ~(P1024o(tmp) | P1024e(tmp) | P512o(tmp) | P512e(tmp) |
754 P256o(tmp) | P256e(tmp) | P128o(tmp) | P128e(tmp));
755 ecc_buf[2] = ~(P4o(tmp) | P4e(tmp) | P2o(tmp) | P2e(tmp) | P1o(tmp) |
756 P1e(tmp) | P2048o(tmp) | P2048e(tmp));
757 }
758
759 /**
760 * omap_compare_ecc - Detect (2 bits) and correct (1 bit) error in data
761 * @ecc_data1: ecc code from nand spare area
762 * @ecc_data2: ecc code from hardware register obtained from hardware ecc
763 * @page_data: page data
764 *
765 * This function compares two ECC's and indicates if there is an error.
766 * If the error can be corrected it will be corrected to the buffer.
767 * If there is no error, %0 is returned. If there is an error but it
768 * was corrected, %1 is returned. Otherwise, %-1 is returned.
769 */
omap_compare_ecc(u8 * ecc_data1,u8 * ecc_data2,u8 * page_data)770 static int omap_compare_ecc(u8 *ecc_data1, /* read from NAND memory */
771 u8 *ecc_data2, /* read from register */
772 u8 *page_data)
773 {
774 uint i;
775 u8 tmp0_bit[8], tmp1_bit[8], tmp2_bit[8];
776 u8 comp0_bit[8], comp1_bit[8], comp2_bit[8];
777 u8 ecc_bit[24];
778 u8 ecc_sum = 0;
779 u8 find_bit = 0;
780 uint find_byte = 0;
781 int isEccFF;
782
783 isEccFF = ((*(u32 *)ecc_data1 & 0xFFFFFF) == 0xFFFFFF);
784
785 gen_true_ecc(ecc_data1);
786 gen_true_ecc(ecc_data2);
787
788 for (i = 0; i <= 2; i++) {
789 *(ecc_data1 + i) = ~(*(ecc_data1 + i));
790 *(ecc_data2 + i) = ~(*(ecc_data2 + i));
791 }
792
793 for (i = 0; i < 8; i++) {
794 tmp0_bit[i] = *ecc_data1 % 2;
795 *ecc_data1 = *ecc_data1 / 2;
796 }
797
798 for (i = 0; i < 8; i++) {
799 tmp1_bit[i] = *(ecc_data1 + 1) % 2;
800 *(ecc_data1 + 1) = *(ecc_data1 + 1) / 2;
801 }
802
803 for (i = 0; i < 8; i++) {
804 tmp2_bit[i] = *(ecc_data1 + 2) % 2;
805 *(ecc_data1 + 2) = *(ecc_data1 + 2) / 2;
806 }
807
808 for (i = 0; i < 8; i++) {
809 comp0_bit[i] = *ecc_data2 % 2;
810 *ecc_data2 = *ecc_data2 / 2;
811 }
812
813 for (i = 0; i < 8; i++) {
814 comp1_bit[i] = *(ecc_data2 + 1) % 2;
815 *(ecc_data2 + 1) = *(ecc_data2 + 1) / 2;
816 }
817
818 for (i = 0; i < 8; i++) {
819 comp2_bit[i] = *(ecc_data2 + 2) % 2;
820 *(ecc_data2 + 2) = *(ecc_data2 + 2) / 2;
821 }
822
823 for (i = 0; i < 6; i++)
824 ecc_bit[i] = tmp2_bit[i + 2] ^ comp2_bit[i + 2];
825
826 for (i = 0; i < 8; i++)
827 ecc_bit[i + 6] = tmp0_bit[i] ^ comp0_bit[i];
828
829 for (i = 0; i < 8; i++)
830 ecc_bit[i + 14] = tmp1_bit[i] ^ comp1_bit[i];
831
832 ecc_bit[22] = tmp2_bit[0] ^ comp2_bit[0];
833 ecc_bit[23] = tmp2_bit[1] ^ comp2_bit[1];
834
835 for (i = 0; i < 24; i++)
836 ecc_sum += ecc_bit[i];
837
838 switch (ecc_sum) {
839 case 0:
840 /* Not reached because this function is not called if
841 * ECC values are equal
842 */
843 return 0;
844
845 case 1:
846 /* Uncorrectable error */
847 pr_debug("ECC UNCORRECTED_ERROR 1\n");
848 return -1;
849
850 case 11:
851 /* UN-Correctable error */
852 pr_debug("ECC UNCORRECTED_ERROR B\n");
853 return -1;
854
855 case 12:
856 /* Correctable error */
857 find_byte = (ecc_bit[23] << 8) +
858 (ecc_bit[21] << 7) +
859 (ecc_bit[19] << 6) +
860 (ecc_bit[17] << 5) +
861 (ecc_bit[15] << 4) +
862 (ecc_bit[13] << 3) +
863 (ecc_bit[11] << 2) +
864 (ecc_bit[9] << 1) +
865 ecc_bit[7];
866
867 find_bit = (ecc_bit[5] << 2) + (ecc_bit[3] << 1) + ecc_bit[1];
868
869 pr_debug("Correcting single bit ECC error at offset: "
870 "%d, bit: %d\n", find_byte, find_bit);
871
872 page_data[find_byte] ^= (1 << find_bit);
873
874 return 1;
875 default:
876 if (isEccFF) {
877 if (ecc_data2[0] == 0 &&
878 ecc_data2[1] == 0 &&
879 ecc_data2[2] == 0)
880 return 0;
881 }
882 pr_debug("UNCORRECTED_ERROR default\n");
883 return -1;
884 }
885 }
886
887 /**
888 * omap_correct_data - Compares the ECC read with HW generated ECC
889 * @mtd: MTD device structure
890 * @dat: page data
891 * @read_ecc: ecc read from nand flash
892 * @calc_ecc: ecc read from HW ECC registers
893 *
894 * Compares the ecc read from nand spare area with ECC registers values
895 * and if ECC's mismatched, it will call 'omap_compare_ecc' for error
896 * detection and correction. If there are no errors, %0 is returned. If
897 * there were errors and all of the errors were corrected, the number of
898 * corrected errors is returned. If uncorrectable errors exist, %-1 is
899 * returned.
900 */
omap_correct_data(struct mtd_info * mtd,u_char * dat,u_char * read_ecc,u_char * calc_ecc)901 static int omap_correct_data(struct mtd_info *mtd, u_char *dat,
902 u_char *read_ecc, u_char *calc_ecc)
903 {
904 struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
905 mtd);
906 int blockCnt = 0, i = 0, ret = 0;
907 int stat = 0;
908
909 /* Ex NAND_ECC_HW12_2048 */
910 if ((info->nand.ecc.mode == NAND_ECC_HW) &&
911 (info->nand.ecc.size == 2048))
912 blockCnt = 4;
913 else
914 blockCnt = 1;
915
916 for (i = 0; i < blockCnt; i++) {
917 if (memcmp(read_ecc, calc_ecc, 3) != 0) {
918 ret = omap_compare_ecc(read_ecc, calc_ecc, dat);
919 if (ret < 0)
920 return ret;
921 /* keep track of the number of corrected errors */
922 stat += ret;
923 }
924 read_ecc += 3;
925 calc_ecc += 3;
926 dat += 512;
927 }
928 return stat;
929 }
930
931 /**
932 * omap_calcuate_ecc - Generate non-inverted ECC bytes.
933 * @mtd: MTD device structure
934 * @dat: The pointer to data on which ecc is computed
935 * @ecc_code: The ecc_code buffer
936 *
937 * Using noninverted ECC can be considered ugly since writing a blank
938 * page ie. padding will clear the ECC bytes. This is no problem as long
939 * nobody is trying to write data on the seemingly unused page. Reading
940 * an erased page will produce an ECC mismatch between generated and read
941 * ECC bytes that has to be dealt with separately.
942 */
omap_calculate_ecc(struct mtd_info * mtd,const u_char * dat,u_char * ecc_code)943 static int omap_calculate_ecc(struct mtd_info *mtd, const u_char *dat,
944 u_char *ecc_code)
945 {
946 struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
947 mtd);
948 u32 val;
949
950 val = readl(info->reg.gpmc_ecc_config);
951 if (((val >> ECC_CONFIG_CS_SHIFT) & ~CS_MASK) != info->gpmc_cs)
952 return -EINVAL;
953
954 /* read ecc result */
955 val = readl(info->reg.gpmc_ecc1_result);
956 *ecc_code++ = val; /* P128e, ..., P1e */
957 *ecc_code++ = val >> 16; /* P128o, ..., P1o */
958 /* P2048o, P1024o, P512o, P256o, P2048e, P1024e, P512e, P256e */
959 *ecc_code++ = ((val >> 8) & 0x0f) | ((val >> 20) & 0xf0);
960
961 return 0;
962 }
963
964 /**
965 * omap_enable_hwecc - This function enables the hardware ecc functionality
966 * @mtd: MTD device structure
967 * @mode: Read/Write mode
968 */
omap_enable_hwecc(struct mtd_info * mtd,int mode)969 static void omap_enable_hwecc(struct mtd_info *mtd, int mode)
970 {
971 struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
972 mtd);
973 struct nand_chip *chip = mtd->priv;
974 unsigned int dev_width = (chip->options & NAND_BUSWIDTH_16) ? 1 : 0;
975 u32 val;
976
977 /* clear ecc and enable bits */
978 val = ECCCLEAR | ECC1;
979 writel(val, info->reg.gpmc_ecc_control);
980
981 /* program ecc and result sizes */
982 val = ((((info->nand.ecc.size >> 1) - 1) << ECCSIZE1_SHIFT) |
983 ECC1RESULTSIZE);
984 writel(val, info->reg.gpmc_ecc_size_config);
985
986 switch (mode) {
987 case NAND_ECC_READ:
988 case NAND_ECC_WRITE:
989 writel(ECCCLEAR | ECC1, info->reg.gpmc_ecc_control);
990 break;
991 case NAND_ECC_READSYN:
992 writel(ECCCLEAR, info->reg.gpmc_ecc_control);
993 break;
994 default:
995 dev_info(&info->pdev->dev,
996 "error: unrecognized Mode[%d]!\n", mode);
997 break;
998 }
999
1000 /* (ECC 16 or 8 bit col) | ( CS ) | ECC Enable */
1001 val = (dev_width << 7) | (info->gpmc_cs << 1) | (0x1);
1002 writel(val, info->reg.gpmc_ecc_config);
1003 }
1004
1005 /**
1006 * omap_wait - wait until the command is done
1007 * @mtd: MTD device structure
1008 * @chip: NAND Chip structure
1009 *
1010 * Wait function is called during Program and erase operations and
1011 * the way it is called from MTD layer, we should wait till the NAND
1012 * chip is ready after the programming/erase operation has completed.
1013 *
1014 * Erase can take up to 400ms and program up to 20ms according to
1015 * general NAND and SmartMedia specs
1016 */
omap_wait(struct mtd_info * mtd,struct nand_chip * chip)1017 static int omap_wait(struct mtd_info *mtd, struct nand_chip *chip)
1018 {
1019 struct nand_chip *this = mtd->priv;
1020 struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
1021 mtd);
1022 unsigned long timeo = jiffies;
1023 int status, state = this->state;
1024
1025 if (state == FL_ERASING)
1026 timeo += msecs_to_jiffies(400);
1027 else
1028 timeo += msecs_to_jiffies(20);
1029
1030 writeb(NAND_CMD_STATUS & 0xFF, info->reg.gpmc_nand_command);
1031 while (time_before(jiffies, timeo)) {
1032 status = readb(info->reg.gpmc_nand_data);
1033 if (status & NAND_STATUS_READY)
1034 break;
1035 cond_resched();
1036 }
1037
1038 status = readb(info->reg.gpmc_nand_data);
1039 return status;
1040 }
1041
1042 /**
1043 * omap_dev_ready - calls the platform specific dev_ready function
1044 * @mtd: MTD device structure
1045 */
omap_dev_ready(struct mtd_info * mtd)1046 static int omap_dev_ready(struct mtd_info *mtd)
1047 {
1048 unsigned int val = 0;
1049 struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
1050 mtd);
1051
1052 val = readl(info->reg.gpmc_status);
1053
1054 if ((val & 0x100) == 0x100) {
1055 return 1;
1056 } else {
1057 return 0;
1058 }
1059 }
1060
1061 #ifdef CONFIG_MTD_NAND_OMAP_BCH
1062
1063 /**
1064 * omap3_enable_hwecc_bch - Program OMAP3 GPMC to perform BCH ECC correction
1065 * @mtd: MTD device structure
1066 * @mode: Read/Write mode
1067 *
1068 * When using BCH, sector size is hardcoded to 512 bytes.
1069 * Using wrapping mode 6 both for reading and writing if ELM module not uses
1070 * for error correction.
1071 * On writing,
1072 * eccsize0 = 0 (no additional protected byte in spare area)
1073 * eccsize1 = 32 (skip 32 nibbles = 16 bytes per sector in spare area)
1074 */
omap3_enable_hwecc_bch(struct mtd_info * mtd,int mode)1075 static void omap3_enable_hwecc_bch(struct mtd_info *mtd, int mode)
1076 {
1077 int nerrors;
1078 unsigned int dev_width, nsectors;
1079 struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
1080 mtd);
1081 struct nand_chip *chip = mtd->priv;
1082 u32 val, wr_mode;
1083 unsigned int ecc_size1, ecc_size0;
1084
1085 /* Using wrapping mode 6 for writing */
1086 wr_mode = BCH_WRAPMODE_6;
1087
1088 /*
1089 * ECC engine enabled for valid ecc_size0 nibbles
1090 * and disabled for ecc_size1 nibbles.
1091 */
1092 ecc_size0 = BCH_ECC_SIZE0;
1093 ecc_size1 = BCH_ECC_SIZE1;
1094
1095 /* Perform ecc calculation on 512-byte sector */
1096 nsectors = 1;
1097
1098 /* Update number of error correction */
1099 nerrors = info->nand.ecc.strength;
1100
1101 /* Multi sector reading/writing for NAND flash with page size < 4096 */
1102 if (info->is_elm_used && (mtd->writesize <= 4096)) {
1103 if (mode == NAND_ECC_READ) {
1104 /* Using wrapping mode 1 for reading */
1105 wr_mode = BCH_WRAPMODE_1;
1106
1107 /*
1108 * ECC engine enabled for ecc_size0 nibbles
1109 * and disabled for ecc_size1 nibbles.
1110 */
1111 ecc_size0 = (nerrors == 8) ?
1112 BCH8R_ECC_SIZE0 : BCH4R_ECC_SIZE0;
1113 ecc_size1 = (nerrors == 8) ?
1114 BCH8R_ECC_SIZE1 : BCH4R_ECC_SIZE1;
1115 }
1116
1117 /* Perform ecc calculation for one page (< 4096) */
1118 nsectors = info->nand.ecc.steps;
1119 }
1120
1121 writel(ECC1, info->reg.gpmc_ecc_control);
1122
1123 /* Configure ecc size for BCH */
1124 val = (ecc_size1 << ECCSIZE1_SHIFT) | (ecc_size0 << ECCSIZE0_SHIFT);
1125 writel(val, info->reg.gpmc_ecc_size_config);
1126
1127 dev_width = (chip->options & NAND_BUSWIDTH_16) ? 1 : 0;
1128
1129 /* BCH configuration */
1130 val = ((1 << 16) | /* enable BCH */
1131 (((nerrors == 8) ? 1 : 0) << 12) | /* 8 or 4 bits */
1132 (wr_mode << 8) | /* wrap mode */
1133 (dev_width << 7) | /* bus width */
1134 (((nsectors-1) & 0x7) << 4) | /* number of sectors */
1135 (info->gpmc_cs << 1) | /* ECC CS */
1136 (0x1)); /* enable ECC */
1137
1138 writel(val, info->reg.gpmc_ecc_config);
1139
1140 /* Clear ecc and enable bits */
1141 writel(ECCCLEAR | ECC1, info->reg.gpmc_ecc_control);
1142 }
1143
1144 /**
1145 * omap3_calculate_ecc_bch4 - Generate 7 bytes of ECC bytes
1146 * @mtd: MTD device structure
1147 * @dat: The pointer to data on which ecc is computed
1148 * @ecc_code: The ecc_code buffer
1149 */
omap3_calculate_ecc_bch4(struct mtd_info * mtd,const u_char * dat,u_char * ecc_code)1150 static int omap3_calculate_ecc_bch4(struct mtd_info *mtd, const u_char *dat,
1151 u_char *ecc_code)
1152 {
1153 struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
1154 mtd);
1155 unsigned long nsectors, val1, val2;
1156 int i;
1157
1158 nsectors = ((readl(info->reg.gpmc_ecc_config) >> 4) & 0x7) + 1;
1159
1160 for (i = 0; i < nsectors; i++) {
1161
1162 /* Read hw-computed remainder */
1163 val1 = readl(info->reg.gpmc_bch_result0[i]);
1164 val2 = readl(info->reg.gpmc_bch_result1[i]);
1165
1166 /*
1167 * Add constant polynomial to remainder, in order to get an ecc
1168 * sequence of 0xFFs for a buffer filled with 0xFFs; and
1169 * left-justify the resulting polynomial.
1170 */
1171 *ecc_code++ = 0x28 ^ ((val2 >> 12) & 0xFF);
1172 *ecc_code++ = 0x13 ^ ((val2 >> 4) & 0xFF);
1173 *ecc_code++ = 0xcc ^ (((val2 & 0xF) << 4)|((val1 >> 28) & 0xF));
1174 *ecc_code++ = 0x39 ^ ((val1 >> 20) & 0xFF);
1175 *ecc_code++ = 0x96 ^ ((val1 >> 12) & 0xFF);
1176 *ecc_code++ = 0xac ^ ((val1 >> 4) & 0xFF);
1177 *ecc_code++ = 0x7f ^ ((val1 & 0xF) << 4);
1178 }
1179
1180 return 0;
1181 }
1182
1183 /**
1184 * omap3_calculate_ecc_bch8 - Generate 13 bytes of ECC bytes
1185 * @mtd: MTD device structure
1186 * @dat: The pointer to data on which ecc is computed
1187 * @ecc_code: The ecc_code buffer
1188 */
omap3_calculate_ecc_bch8(struct mtd_info * mtd,const u_char * dat,u_char * ecc_code)1189 static int omap3_calculate_ecc_bch8(struct mtd_info *mtd, const u_char *dat,
1190 u_char *ecc_code)
1191 {
1192 struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
1193 mtd);
1194 unsigned long nsectors, val1, val2, val3, val4;
1195 int i;
1196
1197 nsectors = ((readl(info->reg.gpmc_ecc_config) >> 4) & 0x7) + 1;
1198
1199 for (i = 0; i < nsectors; i++) {
1200
1201 /* Read hw-computed remainder */
1202 val1 = readl(info->reg.gpmc_bch_result0[i]);
1203 val2 = readl(info->reg.gpmc_bch_result1[i]);
1204 val3 = readl(info->reg.gpmc_bch_result2[i]);
1205 val4 = readl(info->reg.gpmc_bch_result3[i]);
1206
1207 /*
1208 * Add constant polynomial to remainder, in order to get an ecc
1209 * sequence of 0xFFs for a buffer filled with 0xFFs.
1210 */
1211 *ecc_code++ = 0xef ^ (val4 & 0xFF);
1212 *ecc_code++ = 0x51 ^ ((val3 >> 24) & 0xFF);
1213 *ecc_code++ = 0x2e ^ ((val3 >> 16) & 0xFF);
1214 *ecc_code++ = 0x09 ^ ((val3 >> 8) & 0xFF);
1215 *ecc_code++ = 0xed ^ (val3 & 0xFF);
1216 *ecc_code++ = 0x93 ^ ((val2 >> 24) & 0xFF);
1217 *ecc_code++ = 0x9a ^ ((val2 >> 16) & 0xFF);
1218 *ecc_code++ = 0xc2 ^ ((val2 >> 8) & 0xFF);
1219 *ecc_code++ = 0x97 ^ (val2 & 0xFF);
1220 *ecc_code++ = 0x79 ^ ((val1 >> 24) & 0xFF);
1221 *ecc_code++ = 0xe5 ^ ((val1 >> 16) & 0xFF);
1222 *ecc_code++ = 0x24 ^ ((val1 >> 8) & 0xFF);
1223 *ecc_code++ = 0xb5 ^ (val1 & 0xFF);
1224 }
1225
1226 return 0;
1227 }
1228
1229 /**
1230 * omap3_calculate_ecc_bch - Generate bytes of ECC bytes
1231 * @mtd: MTD device structure
1232 * @dat: The pointer to data on which ecc is computed
1233 * @ecc_code: The ecc_code buffer
1234 *
1235 * Support calculating of BCH4/8 ecc vectors for the page
1236 */
omap3_calculate_ecc_bch(struct mtd_info * mtd,const u_char * dat,u_char * ecc_code)1237 static int omap3_calculate_ecc_bch(struct mtd_info *mtd, const u_char *dat,
1238 u_char *ecc_code)
1239 {
1240 struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
1241 mtd);
1242 unsigned long nsectors, bch_val1, bch_val2, bch_val3, bch_val4;
1243 int i, eccbchtsel;
1244
1245 nsectors = ((readl(info->reg.gpmc_ecc_config) >> 4) & 0x7) + 1;
1246 /*
1247 * find BCH scheme used
1248 * 0 -> BCH4
1249 * 1 -> BCH8
1250 */
1251 eccbchtsel = ((readl(info->reg.gpmc_ecc_config) >> 12) & 0x3);
1252
1253 for (i = 0; i < nsectors; i++) {
1254
1255 /* Read hw-computed remainder */
1256 bch_val1 = readl(info->reg.gpmc_bch_result0[i]);
1257 bch_val2 = readl(info->reg.gpmc_bch_result1[i]);
1258 if (eccbchtsel) {
1259 bch_val3 = readl(info->reg.gpmc_bch_result2[i]);
1260 bch_val4 = readl(info->reg.gpmc_bch_result3[i]);
1261 }
1262
1263 if (eccbchtsel) {
1264 /* BCH8 ecc scheme */
1265 *ecc_code++ = (bch_val4 & 0xFF);
1266 *ecc_code++ = ((bch_val3 >> 24) & 0xFF);
1267 *ecc_code++ = ((bch_val3 >> 16) & 0xFF);
1268 *ecc_code++ = ((bch_val3 >> 8) & 0xFF);
1269 *ecc_code++ = (bch_val3 & 0xFF);
1270 *ecc_code++ = ((bch_val2 >> 24) & 0xFF);
1271 *ecc_code++ = ((bch_val2 >> 16) & 0xFF);
1272 *ecc_code++ = ((bch_val2 >> 8) & 0xFF);
1273 *ecc_code++ = (bch_val2 & 0xFF);
1274 *ecc_code++ = ((bch_val1 >> 24) & 0xFF);
1275 *ecc_code++ = ((bch_val1 >> 16) & 0xFF);
1276 *ecc_code++ = ((bch_val1 >> 8) & 0xFF);
1277 *ecc_code++ = (bch_val1 & 0xFF);
1278 /*
1279 * Setting 14th byte to zero to handle
1280 * erased page & maintain compatibility
1281 * with RBL
1282 */
1283 *ecc_code++ = 0x0;
1284 } else {
1285 /* BCH4 ecc scheme */
1286 *ecc_code++ = ((bch_val2 >> 12) & 0xFF);
1287 *ecc_code++ = ((bch_val2 >> 4) & 0xFF);
1288 *ecc_code++ = ((bch_val2 & 0xF) << 4) |
1289 ((bch_val1 >> 28) & 0xF);
1290 *ecc_code++ = ((bch_val1 >> 20) & 0xFF);
1291 *ecc_code++ = ((bch_val1 >> 12) & 0xFF);
1292 *ecc_code++ = ((bch_val1 >> 4) & 0xFF);
1293 *ecc_code++ = ((bch_val1 & 0xF) << 4);
1294 /*
1295 * Setting 8th byte to zero to handle
1296 * erased page
1297 */
1298 *ecc_code++ = 0x0;
1299 }
1300 }
1301
1302 return 0;
1303 }
1304
1305 /**
1306 * erased_sector_bitflips - count bit flips
1307 * @data: data sector buffer
1308 * @oob: oob buffer
1309 * @info: omap_nand_info
1310 *
1311 * Check the bit flips in erased page falls below correctable level.
1312 * If falls below, report the page as erased with correctable bit
1313 * flip, else report as uncorrectable page.
1314 */
erased_sector_bitflips(u_char * data,u_char * oob,struct omap_nand_info * info)1315 static int erased_sector_bitflips(u_char *data, u_char *oob,
1316 struct omap_nand_info *info)
1317 {
1318 int flip_bits = 0, i;
1319
1320 for (i = 0; i < info->nand.ecc.size; i++) {
1321 flip_bits += hweight8(~data[i]);
1322 if (flip_bits > info->nand.ecc.strength)
1323 return 0;
1324 }
1325
1326 for (i = 0; i < info->nand.ecc.bytes - 1; i++) {
1327 flip_bits += hweight8(~oob[i]);
1328 if (flip_bits > info->nand.ecc.strength)
1329 return 0;
1330 }
1331
1332 /*
1333 * Bit flips falls in correctable level.
1334 * Fill data area with 0xFF
1335 */
1336 if (flip_bits) {
1337 memset(data, 0xFF, info->nand.ecc.size);
1338 memset(oob, 0xFF, info->nand.ecc.bytes);
1339 }
1340
1341 return flip_bits;
1342 }
1343
1344 /**
1345 * omap_elm_correct_data - corrects page data area in case error reported
1346 * @mtd: MTD device structure
1347 * @data: page data
1348 * @read_ecc: ecc read from nand flash
1349 * @calc_ecc: ecc read from HW ECC registers
1350 *
1351 * Calculated ecc vector reported as zero in case of non-error pages.
1352 * In case of error/erased pages non-zero error vector is reported.
1353 * In case of non-zero ecc vector, check read_ecc at fixed offset
1354 * (x = 13/7 in case of BCH8/4 == 0) to find page programmed or not.
1355 * To handle bit flips in this data, count the number of 0's in
1356 * read_ecc[x] and check if it greater than 4. If it is less, it is
1357 * programmed page, else erased page.
1358 *
1359 * 1. If page is erased, check with standard ecc vector (ecc vector
1360 * for erased page to find any bit flip). If check fails, bit flip
1361 * is present in erased page. Count the bit flips in erased page and
1362 * if it falls under correctable level, report page with 0xFF and
1363 * update the correctable bit information.
1364 * 2. If error is reported on programmed page, update elm error
1365 * vector and correct the page with ELM error correction routine.
1366 *
1367 */
omap_elm_correct_data(struct mtd_info * mtd,u_char * data,u_char * read_ecc,u_char * calc_ecc)1368 static int omap_elm_correct_data(struct mtd_info *mtd, u_char *data,
1369 u_char *read_ecc, u_char *calc_ecc)
1370 {
1371 struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
1372 mtd);
1373 int eccsteps = info->nand.ecc.steps;
1374 int i , j, stat = 0;
1375 int eccsize, eccflag, ecc_vector_size;
1376 struct elm_errorvec err_vec[ERROR_VECTOR_MAX];
1377 u_char *ecc_vec = calc_ecc;
1378 u_char *spare_ecc = read_ecc;
1379 u_char *erased_ecc_vec;
1380 enum bch_ecc type;
1381 bool is_error_reported = false;
1382
1383 /* Initialize elm error vector to zero */
1384 memset(err_vec, 0, sizeof(err_vec));
1385
1386 if (info->nand.ecc.strength == BCH8_MAX_ERROR) {
1387 type = BCH8_ECC;
1388 erased_ecc_vec = bch8_vector;
1389 } else {
1390 type = BCH4_ECC;
1391 erased_ecc_vec = bch4_vector;
1392 }
1393
1394 ecc_vector_size = info->nand.ecc.bytes;
1395
1396 /*
1397 * Remove extra byte padding for BCH8 RBL
1398 * compatibility and erased page handling
1399 */
1400 eccsize = ecc_vector_size - 1;
1401
1402 for (i = 0; i < eccsteps ; i++) {
1403 eccflag = 0; /* initialize eccflag */
1404
1405 /*
1406 * Check any error reported,
1407 * In case of error, non zero ecc reported.
1408 */
1409
1410 for (j = 0; (j < eccsize); j++) {
1411 if (calc_ecc[j] != 0) {
1412 eccflag = 1; /* non zero ecc, error present */
1413 break;
1414 }
1415 }
1416
1417 if (eccflag == 1) {
1418 /*
1419 * Set threshold to minimum of 4, half of ecc.strength/2
1420 * to allow max bit flip in byte to 4
1421 */
1422 unsigned int threshold = min_t(unsigned int, 4,
1423 info->nand.ecc.strength / 2);
1424
1425 /*
1426 * Check data area is programmed by counting
1427 * number of 0's at fixed offset in spare area.
1428 * Checking count of 0's against threshold.
1429 * In case programmed page expects at least threshold
1430 * zeros in byte.
1431 * If zeros are less than threshold for programmed page/
1432 * zeros are more than threshold erased page, either
1433 * case page reported as uncorrectable.
1434 */
1435 if (hweight8(~read_ecc[eccsize]) >= threshold) {
1436 /*
1437 * Update elm error vector as
1438 * data area is programmed
1439 */
1440 err_vec[i].error_reported = true;
1441 is_error_reported = true;
1442 } else {
1443 /* Error reported in erased page */
1444 int bitflip_count;
1445 u_char *buf = &data[info->nand.ecc.size * i];
1446
1447 if (memcmp(calc_ecc, erased_ecc_vec, eccsize)) {
1448 bitflip_count = erased_sector_bitflips(
1449 buf, read_ecc, info);
1450
1451 if (bitflip_count)
1452 stat += bitflip_count;
1453 else
1454 return -EINVAL;
1455 }
1456 }
1457 }
1458
1459 /* Update the ecc vector */
1460 calc_ecc += ecc_vector_size;
1461 read_ecc += ecc_vector_size;
1462 }
1463
1464 /* Check if any error reported */
1465 if (!is_error_reported)
1466 return 0;
1467
1468 /* Decode BCH error using ELM module */
1469 elm_decode_bch_error_page(info->elm_dev, ecc_vec, err_vec);
1470
1471 for (i = 0; i < eccsteps; i++) {
1472 if (err_vec[i].error_reported) {
1473 for (j = 0; j < err_vec[i].error_count; j++) {
1474 u32 bit_pos, byte_pos, error_max, pos;
1475
1476 if (type == BCH8_ECC)
1477 error_max = BCH8_ECC_MAX;
1478 else
1479 error_max = BCH4_ECC_MAX;
1480
1481 if (info->nand.ecc.strength == BCH8_MAX_ERROR)
1482 pos = err_vec[i].error_loc[j];
1483 else
1484 /* Add 4 to take care 4 bit padding */
1485 pos = err_vec[i].error_loc[j] +
1486 BCH4_BIT_PAD;
1487
1488 /* Calculate bit position of error */
1489 bit_pos = pos % 8;
1490
1491 /* Calculate byte position of error */
1492 byte_pos = (error_max - pos - 1) / 8;
1493
1494 if (pos < error_max) {
1495 if (byte_pos < 512)
1496 data[byte_pos] ^= 1 << bit_pos;
1497 else
1498 spare_ecc[byte_pos - 512] ^=
1499 1 << bit_pos;
1500 }
1501 /* else, not interested to correct ecc */
1502 }
1503 }
1504
1505 /* Update number of correctable errors */
1506 stat += err_vec[i].error_count;
1507
1508 /* Update page data with sector size */
1509 data += info->nand.ecc.size;
1510 spare_ecc += ecc_vector_size;
1511 }
1512
1513 for (i = 0; i < eccsteps; i++)
1514 /* Return error if uncorrectable error present */
1515 if (err_vec[i].error_uncorrectable)
1516 return -EINVAL;
1517
1518 return stat;
1519 }
1520
1521 /**
1522 * omap3_correct_data_bch - Decode received data and correct errors
1523 * @mtd: MTD device structure
1524 * @data: page data
1525 * @read_ecc: ecc read from nand flash
1526 * @calc_ecc: ecc read from HW ECC registers
1527 */
omap3_correct_data_bch(struct mtd_info * mtd,u_char * data,u_char * read_ecc,u_char * calc_ecc)1528 static int omap3_correct_data_bch(struct mtd_info *mtd, u_char *data,
1529 u_char *read_ecc, u_char *calc_ecc)
1530 {
1531 int i, count;
1532 /* cannot correct more than 8 errors */
1533 unsigned int errloc[8];
1534 struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
1535 mtd);
1536
1537 count = decode_bch(info->bch, NULL, 512, read_ecc, calc_ecc, NULL,
1538 errloc);
1539 if (count > 0) {
1540 /* correct errors */
1541 for (i = 0; i < count; i++) {
1542 /* correct data only, not ecc bytes */
1543 if (errloc[i] < 8*512)
1544 data[errloc[i]/8] ^= 1 << (errloc[i] & 7);
1545 pr_debug("corrected bitflip %u\n", errloc[i]);
1546 }
1547 } else if (count < 0) {
1548 pr_err("ecc unrecoverable error\n");
1549 }
1550 return count;
1551 }
1552
1553 /**
1554 * omap_write_page_bch - BCH ecc based write page function for entire page
1555 * @mtd: mtd info structure
1556 * @chip: nand chip info structure
1557 * @buf: data buffer
1558 * @oob_required: must write chip->oob_poi to OOB
1559 *
1560 * Custom write page method evolved to support multi sector writing in one shot
1561 */
omap_write_page_bch(struct mtd_info * mtd,struct nand_chip * chip,const uint8_t * buf,int oob_required)1562 static int omap_write_page_bch(struct mtd_info *mtd, struct nand_chip *chip,
1563 const uint8_t *buf, int oob_required)
1564 {
1565 int i;
1566 uint8_t *ecc_calc = chip->buffers->ecccalc;
1567 uint32_t *eccpos = chip->ecc.layout->eccpos;
1568
1569 /* Enable GPMC ecc engine */
1570 chip->ecc.hwctl(mtd, NAND_ECC_WRITE);
1571
1572 /* Write data */
1573 chip->write_buf(mtd, buf, mtd->writesize);
1574
1575 /* Update ecc vector from GPMC result registers */
1576 chip->ecc.calculate(mtd, buf, &ecc_calc[0]);
1577
1578 for (i = 0; i < chip->ecc.total; i++)
1579 chip->oob_poi[eccpos[i]] = ecc_calc[i];
1580
1581 /* Write ecc vector to OOB area */
1582 chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
1583 return 0;
1584 }
1585
1586 /**
1587 * omap_read_page_bch - BCH ecc based page read function for entire page
1588 * @mtd: mtd info structure
1589 * @chip: nand chip info structure
1590 * @buf: buffer to store read data
1591 * @oob_required: caller requires OOB data read to chip->oob_poi
1592 * @page: page number to read
1593 *
1594 * For BCH ecc scheme, GPMC used for syndrome calculation and ELM module
1595 * used for error correction.
1596 * Custom method evolved to support ELM error correction & multi sector
1597 * reading. On reading page data area is read along with OOB data with
1598 * ecc engine enabled. ecc vector updated after read of OOB data.
1599 * For non error pages ecc vector reported as zero.
1600 */
omap_read_page_bch(struct mtd_info * mtd,struct nand_chip * chip,uint8_t * buf,int oob_required,int page)1601 static int omap_read_page_bch(struct mtd_info *mtd, struct nand_chip *chip,
1602 uint8_t *buf, int oob_required, int page)
1603 {
1604 uint8_t *ecc_calc = chip->buffers->ecccalc;
1605 uint8_t *ecc_code = chip->buffers->ecccode;
1606 uint32_t *eccpos = chip->ecc.layout->eccpos;
1607 uint8_t *oob = &chip->oob_poi[eccpos[0]];
1608 uint32_t oob_pos = mtd->writesize + chip->ecc.layout->eccpos[0];
1609 int stat;
1610 unsigned int max_bitflips = 0;
1611
1612 /* Enable GPMC ecc engine */
1613 chip->ecc.hwctl(mtd, NAND_ECC_READ);
1614
1615 /* Read data */
1616 chip->read_buf(mtd, buf, mtd->writesize);
1617
1618 /* Read oob bytes */
1619 chip->cmdfunc(mtd, NAND_CMD_RNDOUT, oob_pos, -1);
1620 chip->read_buf(mtd, oob, chip->ecc.total);
1621
1622 /* Calculate ecc bytes */
1623 chip->ecc.calculate(mtd, buf, ecc_calc);
1624
1625 memcpy(ecc_code, &chip->oob_poi[eccpos[0]], chip->ecc.total);
1626
1627 stat = chip->ecc.correct(mtd, buf, ecc_code, ecc_calc);
1628
1629 if (stat < 0) {
1630 mtd->ecc_stats.failed++;
1631 } else {
1632 mtd->ecc_stats.corrected += stat;
1633 max_bitflips = max_t(unsigned int, max_bitflips, stat);
1634 }
1635
1636 return max_bitflips;
1637 }
1638
1639 /**
1640 * omap3_free_bch - Release BCH ecc resources
1641 * @mtd: MTD device structure
1642 */
omap3_free_bch(struct mtd_info * mtd)1643 static void omap3_free_bch(struct mtd_info *mtd)
1644 {
1645 struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
1646 mtd);
1647 if (info->bch) {
1648 free_bch(info->bch);
1649 info->bch = NULL;
1650 }
1651 }
1652
1653 /**
1654 * omap3_init_bch - Initialize BCH ECC
1655 * @mtd: MTD device structure
1656 * @ecc_opt: OMAP ECC mode (OMAP_ECC_BCH4_CODE_HW or OMAP_ECC_BCH8_CODE_HW)
1657 */
omap3_init_bch(struct mtd_info * mtd,int ecc_opt)1658 static int omap3_init_bch(struct mtd_info *mtd, int ecc_opt)
1659 {
1660 int max_errors;
1661 struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
1662 mtd);
1663 #ifdef CONFIG_MTD_NAND_OMAP_BCH8
1664 const int hw_errors = BCH8_MAX_ERROR;
1665 #else
1666 const int hw_errors = BCH4_MAX_ERROR;
1667 #endif
1668 enum bch_ecc bch_type;
1669 const __be32 *parp;
1670 int lenp;
1671 struct device_node *elm_node;
1672
1673 info->bch = NULL;
1674
1675 max_errors = (ecc_opt == OMAP_ECC_BCH8_CODE_HW) ?
1676 BCH8_MAX_ERROR : BCH4_MAX_ERROR;
1677 if (max_errors != hw_errors) {
1678 pr_err("cannot configure %d-bit BCH ecc, only %d-bit supported",
1679 max_errors, hw_errors);
1680 goto fail;
1681 }
1682
1683 info->nand.ecc.size = 512;
1684 info->nand.ecc.hwctl = omap3_enable_hwecc_bch;
1685 info->nand.ecc.mode = NAND_ECC_HW;
1686 info->nand.ecc.strength = max_errors;
1687
1688 if (hw_errors == BCH8_MAX_ERROR)
1689 bch_type = BCH8_ECC;
1690 else
1691 bch_type = BCH4_ECC;
1692
1693 /* Detect availability of ELM module */
1694 parp = of_get_property(info->of_node, "elm_id", &lenp);
1695 if ((parp == NULL) && (lenp != (sizeof(void *) * 2))) {
1696 pr_err("Missing elm_id property, fall back to Software BCH\n");
1697 info->is_elm_used = false;
1698 } else {
1699 struct platform_device *pdev;
1700
1701 elm_node = of_find_node_by_phandle(be32_to_cpup(parp));
1702 pdev = of_find_device_by_node(elm_node);
1703 info->elm_dev = &pdev->dev;
1704
1705 if (elm_config(info->elm_dev, bch_type) == 0)
1706 info->is_elm_used = true;
1707 }
1708
1709 if (info->is_elm_used && (mtd->writesize <= 4096)) {
1710
1711 if (hw_errors == BCH8_MAX_ERROR)
1712 info->nand.ecc.bytes = BCH8_SIZE;
1713 else
1714 info->nand.ecc.bytes = BCH4_SIZE;
1715
1716 info->nand.ecc.correct = omap_elm_correct_data;
1717 info->nand.ecc.calculate = omap3_calculate_ecc_bch;
1718 info->nand.ecc.read_page = omap_read_page_bch;
1719 info->nand.ecc.write_page = omap_write_page_bch;
1720 } else {
1721 /*
1722 * software bch library is only used to detect and
1723 * locate errors
1724 */
1725 info->bch = init_bch(13, max_errors,
1726 0x201b /* hw polynomial */);
1727 if (!info->bch)
1728 goto fail;
1729
1730 info->nand.ecc.correct = omap3_correct_data_bch;
1731
1732 /*
1733 * The number of corrected errors in an ecc block that will
1734 * trigger block scrubbing defaults to the ecc strength (4 or 8)
1735 * Set mtd->bitflip_threshold here to define a custom threshold.
1736 */
1737
1738 if (max_errors == 8) {
1739 info->nand.ecc.bytes = 13;
1740 info->nand.ecc.calculate = omap3_calculate_ecc_bch8;
1741 } else {
1742 info->nand.ecc.bytes = 7;
1743 info->nand.ecc.calculate = omap3_calculate_ecc_bch4;
1744 }
1745 }
1746
1747 pr_info("enabling NAND BCH ecc with %d-bit correction\n", max_errors);
1748 return 0;
1749 fail:
1750 omap3_free_bch(mtd);
1751 return -1;
1752 }
1753
1754 /**
1755 * omap3_init_bch_tail - Build an oob layout for BCH ECC correction.
1756 * @mtd: MTD device structure
1757 */
omap3_init_bch_tail(struct mtd_info * mtd)1758 static int omap3_init_bch_tail(struct mtd_info *mtd)
1759 {
1760 int i, steps, offset;
1761 struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
1762 mtd);
1763 struct nand_ecclayout *layout = &info->ecclayout;
1764
1765 /* build oob layout */
1766 steps = mtd->writesize/info->nand.ecc.size;
1767 layout->eccbytes = steps*info->nand.ecc.bytes;
1768
1769 /* do not bother creating special oob layouts for small page devices */
1770 if (mtd->oobsize < 64) {
1771 pr_err("BCH ecc is not supported on small page devices\n");
1772 goto fail;
1773 }
1774
1775 /* reserve 2 bytes for bad block marker */
1776 if (layout->eccbytes+2 > mtd->oobsize) {
1777 pr_err("no oob layout available for oobsize %d eccbytes %u\n",
1778 mtd->oobsize, layout->eccbytes);
1779 goto fail;
1780 }
1781
1782 /* ECC layout compatible with RBL for BCH8 */
1783 if (info->is_elm_used && (info->nand.ecc.bytes == BCH8_SIZE))
1784 offset = 2;
1785 else
1786 offset = mtd->oobsize - layout->eccbytes;
1787
1788 /* put ecc bytes at oob tail */
1789 for (i = 0; i < layout->eccbytes; i++)
1790 layout->eccpos[i] = offset + i;
1791
1792 if (info->is_elm_used && (info->nand.ecc.bytes == BCH8_SIZE))
1793 layout->oobfree[0].offset = 2 + layout->eccbytes * steps;
1794 else
1795 layout->oobfree[0].offset = 2;
1796
1797 layout->oobfree[0].length = mtd->oobsize-2-layout->eccbytes;
1798 info->nand.ecc.layout = layout;
1799
1800 if (!(info->nand.options & NAND_BUSWIDTH_16))
1801 info->nand.badblock_pattern = &bb_descrip_flashbased;
1802 return 0;
1803 fail:
1804 omap3_free_bch(mtd);
1805 return -1;
1806 }
1807
1808 #else
omap3_init_bch(struct mtd_info * mtd,int ecc_opt)1809 static int omap3_init_bch(struct mtd_info *mtd, int ecc_opt)
1810 {
1811 pr_err("CONFIG_MTD_NAND_OMAP_BCH is not enabled\n");
1812 return -1;
1813 }
omap3_init_bch_tail(struct mtd_info * mtd)1814 static int omap3_init_bch_tail(struct mtd_info *mtd)
1815 {
1816 return -1;
1817 }
omap3_free_bch(struct mtd_info * mtd)1818 static void omap3_free_bch(struct mtd_info *mtd)
1819 {
1820 }
1821 #endif /* CONFIG_MTD_NAND_OMAP_BCH */
1822
omap_nand_probe(struct platform_device * pdev)1823 static int omap_nand_probe(struct platform_device *pdev)
1824 {
1825 struct omap_nand_info *info;
1826 struct omap_nand_platform_data *pdata;
1827 int err;
1828 int i, offset;
1829 dma_cap_mask_t mask;
1830 unsigned sig;
1831 struct resource *res;
1832 struct mtd_part_parser_data ppdata = {};
1833
1834 pdata = pdev->dev.platform_data;
1835 if (pdata == NULL) {
1836 dev_err(&pdev->dev, "platform data missing\n");
1837 return -ENODEV;
1838 }
1839
1840 info = kzalloc(sizeof(struct omap_nand_info), GFP_KERNEL);
1841 if (!info)
1842 return -ENOMEM;
1843
1844 platform_set_drvdata(pdev, info);
1845
1846 spin_lock_init(&info->controller.lock);
1847 init_waitqueue_head(&info->controller.wq);
1848
1849 info->pdev = pdev;
1850
1851 info->gpmc_cs = pdata->cs;
1852 info->reg = pdata->reg;
1853
1854 info->mtd.priv = &info->nand;
1855 info->mtd.name = dev_name(&pdev->dev);
1856 info->mtd.owner = THIS_MODULE;
1857
1858 info->nand.options = pdata->devsize;
1859 info->nand.options |= NAND_SKIP_BBTSCAN;
1860 #ifdef CONFIG_MTD_NAND_OMAP_BCH
1861 info->of_node = pdata->of_node;
1862 #endif
1863
1864 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1865 if (res == NULL) {
1866 err = -EINVAL;
1867 dev_err(&pdev->dev, "error getting memory resource\n");
1868 goto out_free_info;
1869 }
1870
1871 info->phys_base = res->start;
1872 info->mem_size = resource_size(res);
1873
1874 if (!request_mem_region(info->phys_base, info->mem_size,
1875 pdev->dev.driver->name)) {
1876 err = -EBUSY;
1877 goto out_free_info;
1878 }
1879
1880 info->nand.IO_ADDR_R = ioremap(info->phys_base, info->mem_size);
1881 if (!info->nand.IO_ADDR_R) {
1882 err = -ENOMEM;
1883 goto out_release_mem_region;
1884 }
1885
1886 info->nand.controller = &info->controller;
1887
1888 info->nand.IO_ADDR_W = info->nand.IO_ADDR_R;
1889 info->nand.cmd_ctrl = omap_hwcontrol;
1890
1891 /*
1892 * If RDY/BSY line is connected to OMAP then use the omap ready
1893 * function and the generic nand_wait function which reads the status
1894 * register after monitoring the RDY/BSY line. Otherwise use a standard
1895 * chip delay which is slightly more than tR (AC Timing) of the NAND
1896 * device and read status register until you get a failure or success
1897 */
1898 if (pdata->dev_ready) {
1899 info->nand.dev_ready = omap_dev_ready;
1900 info->nand.chip_delay = 0;
1901 } else {
1902 info->nand.waitfunc = omap_wait;
1903 info->nand.chip_delay = 50;
1904 }
1905
1906 switch (pdata->xfer_type) {
1907 case NAND_OMAP_PREFETCH_POLLED:
1908 info->nand.read_buf = omap_read_buf_pref;
1909 info->nand.write_buf = omap_write_buf_pref;
1910 break;
1911
1912 case NAND_OMAP_POLLED:
1913 if (info->nand.options & NAND_BUSWIDTH_16) {
1914 info->nand.read_buf = omap_read_buf16;
1915 info->nand.write_buf = omap_write_buf16;
1916 } else {
1917 info->nand.read_buf = omap_read_buf8;
1918 info->nand.write_buf = omap_write_buf8;
1919 }
1920 break;
1921
1922 case NAND_OMAP_PREFETCH_DMA:
1923 dma_cap_zero(mask);
1924 dma_cap_set(DMA_SLAVE, mask);
1925 sig = OMAP24XX_DMA_GPMC;
1926 info->dma = dma_request_channel(mask, omap_dma_filter_fn, &sig);
1927 if (!info->dma) {
1928 dev_err(&pdev->dev, "DMA engine request failed\n");
1929 err = -ENXIO;
1930 goto out_release_mem_region;
1931 } else {
1932 struct dma_slave_config cfg;
1933
1934 memset(&cfg, 0, sizeof(cfg));
1935 cfg.src_addr = info->phys_base;
1936 cfg.dst_addr = info->phys_base;
1937 cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1938 cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1939 cfg.src_maxburst = 16;
1940 cfg.dst_maxburst = 16;
1941 err = dmaengine_slave_config(info->dma, &cfg);
1942 if (err) {
1943 dev_err(&pdev->dev, "DMA engine slave config failed: %d\n",
1944 err);
1945 goto out_release_mem_region;
1946 }
1947 info->nand.read_buf = omap_read_buf_dma_pref;
1948 info->nand.write_buf = omap_write_buf_dma_pref;
1949 }
1950 break;
1951
1952 case NAND_OMAP_PREFETCH_IRQ:
1953 info->gpmc_irq_fifo = platform_get_irq(pdev, 0);
1954 if (info->gpmc_irq_fifo <= 0) {
1955 dev_err(&pdev->dev, "error getting fifo irq\n");
1956 err = -ENODEV;
1957 goto out_release_mem_region;
1958 }
1959 err = request_irq(info->gpmc_irq_fifo, omap_nand_irq,
1960 IRQF_SHARED, "gpmc-nand-fifo", info);
1961 if (err) {
1962 dev_err(&pdev->dev, "requesting irq(%d) error:%d",
1963 info->gpmc_irq_fifo, err);
1964 info->gpmc_irq_fifo = 0;
1965 goto out_release_mem_region;
1966 }
1967
1968 info->gpmc_irq_count = platform_get_irq(pdev, 1);
1969 if (info->gpmc_irq_count <= 0) {
1970 dev_err(&pdev->dev, "error getting count irq\n");
1971 err = -ENODEV;
1972 goto out_release_mem_region;
1973 }
1974 err = request_irq(info->gpmc_irq_count, omap_nand_irq,
1975 IRQF_SHARED, "gpmc-nand-count", info);
1976 if (err) {
1977 dev_err(&pdev->dev, "requesting irq(%d) error:%d",
1978 info->gpmc_irq_count, err);
1979 info->gpmc_irq_count = 0;
1980 goto out_release_mem_region;
1981 }
1982
1983 info->nand.read_buf = omap_read_buf_irq_pref;
1984 info->nand.write_buf = omap_write_buf_irq_pref;
1985
1986 break;
1987
1988 default:
1989 dev_err(&pdev->dev,
1990 "xfer_type(%d) not supported!\n", pdata->xfer_type);
1991 err = -EINVAL;
1992 goto out_release_mem_region;
1993 }
1994
1995 /* select the ecc type */
1996 if (pdata->ecc_opt == OMAP_ECC_HAMMING_CODE_DEFAULT)
1997 info->nand.ecc.mode = NAND_ECC_SOFT;
1998 else if ((pdata->ecc_opt == OMAP_ECC_HAMMING_CODE_HW) ||
1999 (pdata->ecc_opt == OMAP_ECC_HAMMING_CODE_HW_ROMCODE)) {
2000 info->nand.ecc.bytes = 3;
2001 info->nand.ecc.size = 512;
2002 info->nand.ecc.strength = 1;
2003 info->nand.ecc.calculate = omap_calculate_ecc;
2004 info->nand.ecc.hwctl = omap_enable_hwecc;
2005 info->nand.ecc.correct = omap_correct_data;
2006 info->nand.ecc.mode = NAND_ECC_HW;
2007 } else if ((pdata->ecc_opt == OMAP_ECC_BCH4_CODE_HW) ||
2008 (pdata->ecc_opt == OMAP_ECC_BCH8_CODE_HW)) {
2009 err = omap3_init_bch(&info->mtd, pdata->ecc_opt);
2010 if (err) {
2011 err = -EINVAL;
2012 goto out_release_mem_region;
2013 }
2014 }
2015
2016 /* DIP switches on some boards change between 8 and 16 bit
2017 * bus widths for flash. Try the other width if the first try fails.
2018 */
2019 if (nand_scan_ident(&info->mtd, 1, NULL)) {
2020 info->nand.options ^= NAND_BUSWIDTH_16;
2021 if (nand_scan_ident(&info->mtd, 1, NULL)) {
2022 err = -ENXIO;
2023 goto out_release_mem_region;
2024 }
2025 }
2026
2027 /* rom code layout */
2028 if (pdata->ecc_opt == OMAP_ECC_HAMMING_CODE_HW_ROMCODE) {
2029
2030 if (info->nand.options & NAND_BUSWIDTH_16)
2031 offset = 2;
2032 else {
2033 offset = 1;
2034 info->nand.badblock_pattern = &bb_descrip_flashbased;
2035 }
2036 omap_oobinfo.eccbytes = 3 * (info->mtd.oobsize/16);
2037 for (i = 0; i < omap_oobinfo.eccbytes; i++)
2038 omap_oobinfo.eccpos[i] = i+offset;
2039
2040 omap_oobinfo.oobfree->offset = offset + omap_oobinfo.eccbytes;
2041 omap_oobinfo.oobfree->length = info->mtd.oobsize -
2042 (offset + omap_oobinfo.eccbytes);
2043
2044 info->nand.ecc.layout = &omap_oobinfo;
2045 } else if ((pdata->ecc_opt == OMAP_ECC_BCH4_CODE_HW) ||
2046 (pdata->ecc_opt == OMAP_ECC_BCH8_CODE_HW)) {
2047 /* build OOB layout for BCH ECC correction */
2048 err = omap3_init_bch_tail(&info->mtd);
2049 if (err) {
2050 err = -EINVAL;
2051 goto out_release_mem_region;
2052 }
2053 }
2054
2055 /* second phase scan */
2056 if (nand_scan_tail(&info->mtd)) {
2057 err = -ENXIO;
2058 goto out_release_mem_region;
2059 }
2060
2061 ppdata.of_node = pdata->of_node;
2062 mtd_device_parse_register(&info->mtd, NULL, &ppdata, pdata->parts,
2063 pdata->nr_parts);
2064
2065 platform_set_drvdata(pdev, &info->mtd);
2066
2067 return 0;
2068
2069 out_release_mem_region:
2070 if (info->dma)
2071 dma_release_channel(info->dma);
2072 if (info->gpmc_irq_count > 0)
2073 free_irq(info->gpmc_irq_count, info);
2074 if (info->gpmc_irq_fifo > 0)
2075 free_irq(info->gpmc_irq_fifo, info);
2076 release_mem_region(info->phys_base, info->mem_size);
2077 out_free_info:
2078 kfree(info);
2079
2080 return err;
2081 }
2082
omap_nand_remove(struct platform_device * pdev)2083 static int omap_nand_remove(struct platform_device *pdev)
2084 {
2085 struct mtd_info *mtd = platform_get_drvdata(pdev);
2086 struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
2087 mtd);
2088 omap3_free_bch(&info->mtd);
2089
2090 platform_set_drvdata(pdev, NULL);
2091 if (info->dma)
2092 dma_release_channel(info->dma);
2093
2094 if (info->gpmc_irq_count > 0)
2095 free_irq(info->gpmc_irq_count, info);
2096 if (info->gpmc_irq_fifo > 0)
2097 free_irq(info->gpmc_irq_fifo, info);
2098
2099 /* Release NAND device, its internal structures and partitions */
2100 nand_release(&info->mtd);
2101 iounmap(info->nand.IO_ADDR_R);
2102 release_mem_region(info->phys_base, info->mem_size);
2103 kfree(info);
2104 return 0;
2105 }
2106
2107 static struct platform_driver omap_nand_driver = {
2108 .probe = omap_nand_probe,
2109 .remove = omap_nand_remove,
2110 .driver = {
2111 .name = DRIVER_NAME,
2112 .owner = THIS_MODULE,
2113 },
2114 };
2115
2116 module_platform_driver(omap_nand_driver);
2117
2118 MODULE_ALIAS("platform:" DRIVER_NAME);
2119 MODULE_LICENSE("GPL");
2120 MODULE_DESCRIPTION("Glue layer for NAND flash on TI OMAP boards");
2121