Version:  2.0.40 2.2.26 2.4.37 2.6.39 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 3.10 3.11 3.12 3.13 3.14 3.15

Linux/drivers/mtd/nand/omap2.c

  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 #include <linux/mtd/nand_bch.h>
 29 #include <linux/platform_data/elm.h>
 30 
 31 #include <linux/platform_data/mtd-nand-omap2.h>
 32 
 33 #define DRIVER_NAME     "omap2-nand"
 34 #define OMAP_NAND_TIMEOUT_MS    5000
 35 
 36 #define NAND_Ecc_P1e            (1 << 0)
 37 #define NAND_Ecc_P2e            (1 << 1)
 38 #define NAND_Ecc_P4e            (1 << 2)
 39 #define NAND_Ecc_P8e            (1 << 3)
 40 #define NAND_Ecc_P16e           (1 << 4)
 41 #define NAND_Ecc_P32e           (1 << 5)
 42 #define NAND_Ecc_P64e           (1 << 6)
 43 #define NAND_Ecc_P128e          (1 << 7)
 44 #define NAND_Ecc_P256e          (1 << 8)
 45 #define NAND_Ecc_P512e          (1 << 9)
 46 #define NAND_Ecc_P1024e         (1 << 10)
 47 #define NAND_Ecc_P2048e         (1 << 11)
 48 
 49 #define NAND_Ecc_P1o            (1 << 16)
 50 #define NAND_Ecc_P2o            (1 << 17)
 51 #define NAND_Ecc_P4o            (1 << 18)
 52 #define NAND_Ecc_P8o            (1 << 19)
 53 #define NAND_Ecc_P16o           (1 << 20)
 54 #define NAND_Ecc_P32o           (1 << 21)
 55 #define NAND_Ecc_P64o           (1 << 22)
 56 #define NAND_Ecc_P128o          (1 << 23)
 57 #define NAND_Ecc_P256o          (1 << 24)
 58 #define NAND_Ecc_P512o          (1 << 25)
 59 #define NAND_Ecc_P1024o         (1 << 26)
 60 #define NAND_Ecc_P2048o         (1 << 27)
 61 
 62 #define TF(value)       (value ? 1 : 0)
 63 
 64 #define P2048e(a)       (TF(a & NAND_Ecc_P2048e)        << 0)
 65 #define P2048o(a)       (TF(a & NAND_Ecc_P2048o)        << 1)
 66 #define P1e(a)          (TF(a & NAND_Ecc_P1e)           << 2)
 67 #define P1o(a)          (TF(a & NAND_Ecc_P1o)           << 3)
 68 #define P2e(a)          (TF(a & NAND_Ecc_P2e)           << 4)
 69 #define P2o(a)          (TF(a & NAND_Ecc_P2o)           << 5)
 70 #define P4e(a)          (TF(a & NAND_Ecc_P4e)           << 6)
 71 #define P4o(a)          (TF(a & NAND_Ecc_P4o)           << 7)
 72 
 73 #define P8e(a)          (TF(a & NAND_Ecc_P8e)           << 0)
 74 #define P8o(a)          (TF(a & NAND_Ecc_P8o)           << 1)
 75 #define P16e(a)         (TF(a & NAND_Ecc_P16e)          << 2)
 76 #define P16o(a)         (TF(a & NAND_Ecc_P16o)          << 3)
 77 #define P32e(a)         (TF(a & NAND_Ecc_P32e)          << 4)
 78 #define P32o(a)         (TF(a & NAND_Ecc_P32o)          << 5)
 79 #define P64e(a)         (TF(a & NAND_Ecc_P64e)          << 6)
 80 #define P64o(a)         (TF(a & NAND_Ecc_P64o)          << 7)
 81 
 82 #define P128e(a)        (TF(a & NAND_Ecc_P128e)         << 0)
 83 #define P128o(a)        (TF(a & NAND_Ecc_P128o)         << 1)
 84 #define P256e(a)        (TF(a & NAND_Ecc_P256e)         << 2)
 85 #define P256o(a)        (TF(a & NAND_Ecc_P256o)         << 3)
 86 #define P512e(a)        (TF(a & NAND_Ecc_P512e)         << 4)
 87 #define P512o(a)        (TF(a & NAND_Ecc_P512o)         << 5)
 88 #define P1024e(a)       (TF(a & NAND_Ecc_P1024e)        << 6)
 89 #define P1024o(a)       (TF(a & NAND_Ecc_P1024o)        << 7)
 90 
 91 #define P8e_s(a)        (TF(a & NAND_Ecc_P8e)           << 0)
 92 #define P8o_s(a)        (TF(a & NAND_Ecc_P8o)           << 1)
 93 #define P16e_s(a)       (TF(a & NAND_Ecc_P16e)          << 2)
 94 #define P16o_s(a)       (TF(a & NAND_Ecc_P16o)          << 3)
 95 #define P1e_s(a)        (TF(a & NAND_Ecc_P1e)           << 4)
 96 #define P1o_s(a)        (TF(a & NAND_Ecc_P1o)           << 5)
 97 #define P2e_s(a)        (TF(a & NAND_Ecc_P2e)           << 6)
 98 #define P2o_s(a)        (TF(a & NAND_Ecc_P2o)           << 7)
 99 
100 #define P4e_s(a)        (TF(a & NAND_Ecc_P4e)           << 0)
101 #define P4o_s(a)        (TF(a & NAND_Ecc_P4o)           << 1)
102 
103 #define PREFETCH_CONFIG1_CS_SHIFT       24
104 #define ECC_CONFIG_CS_SHIFT             1
105 #define CS_MASK                         0x7
106 #define ENABLE_PREFETCH                 (0x1 << 7)
107 #define DMA_MPU_MODE_SHIFT              2
108 #define ECCSIZE0_SHIFT                  12
109 #define ECCSIZE1_SHIFT                  22
110 #define ECC1RESULTSIZE                  0x1
111 #define ECCCLEAR                        0x100
112 #define ECC1                            0x1
113 #define PREFETCH_FIFOTHRESHOLD_MAX      0x40
114 #define PREFETCH_FIFOTHRESHOLD(val)     ((val) << 8)
115 #define PREFETCH_STATUS_COUNT(val)      (val & 0x00003fff)
116 #define PREFETCH_STATUS_FIFO_CNT(val)   ((val >> 24) & 0x7F)
117 #define STATUS_BUFF_EMPTY               0x00000001
118 
119 #define OMAP24XX_DMA_GPMC               4
120 
121 #define SECTOR_BYTES            512
122 /* 4 bit padding to make byte aligned, 56 = 52 + 4 */
123 #define BCH4_BIT_PAD            4
124 
125 /* GPMC ecc engine settings for read */
126 #define BCH_WRAPMODE_1          1       /* BCH wrap mode 1 */
127 #define BCH8R_ECC_SIZE0         0x1a    /* ecc_size0 = 26 */
128 #define BCH8R_ECC_SIZE1         0x2     /* ecc_size1 = 2 */
129 #define BCH4R_ECC_SIZE0         0xd     /* ecc_size0 = 13 */
130 #define BCH4R_ECC_SIZE1         0x3     /* ecc_size1 = 3 */
131 
132 /* GPMC ecc engine settings for write */
133 #define BCH_WRAPMODE_6          6       /* BCH wrap mode 6 */
134 #define BCH_ECC_SIZE0           0x0     /* ecc_size0 = 0, no oob protection */
135 #define BCH_ECC_SIZE1           0x20    /* ecc_size1 = 32 */
136 
137 #define BADBLOCK_MARKER_LENGTH          2
138 
139 #ifdef CONFIG_MTD_NAND_OMAP_BCH
140 static u_char bch8_vector[] = {0xf3, 0xdb, 0x14, 0x16, 0x8b, 0xd2, 0xbe, 0xcc,
141         0xac, 0x6b, 0xff, 0x99, 0x7b};
142 static u_char bch4_vector[] = {0x00, 0x6b, 0x31, 0xdd, 0x41, 0xbc, 0x10};
143 #endif
144 
145 /* oob info generated runtime depending on ecc algorithm and layout selected */
146 static struct nand_ecclayout omap_oobinfo;
147 
148 struct omap_nand_info {
149         struct nand_hw_control          controller;
150         struct omap_nand_platform_data  *pdata;
151         struct mtd_info                 mtd;
152         struct nand_chip                nand;
153         struct platform_device          *pdev;
154 
155         int                             gpmc_cs;
156         unsigned long                   phys_base;
157         enum omap_ecc                   ecc_opt;
158         struct completion               comp;
159         struct dma_chan                 *dma;
160         int                             gpmc_irq_fifo;
161         int                             gpmc_irq_count;
162         enum {
163                 OMAP_NAND_IO_READ = 0,  /* read */
164                 OMAP_NAND_IO_WRITE,     /* write */
165         } iomode;
166         u_char                          *buf;
167         int                                     buf_len;
168         struct gpmc_nand_regs           reg;
169         /* fields specific for BCHx_HW ECC scheme */
170         struct device                   *elm_dev;
171         struct device_node              *of_node;
172 };
173 
174 /**
175  * omap_prefetch_enable - configures and starts prefetch transfer
176  * @cs: cs (chip select) number
177  * @fifo_th: fifo threshold to be used for read/ write
178  * @dma_mode: dma mode enable (1) or disable (0)
179  * @u32_count: number of bytes to be transferred
180  * @is_write: prefetch read(0) or write post(1) mode
181  */
182 static int omap_prefetch_enable(int cs, int fifo_th, int dma_mode,
183         unsigned int u32_count, int is_write, struct omap_nand_info *info)
184 {
185         u32 val;
186 
187         if (fifo_th > PREFETCH_FIFOTHRESHOLD_MAX)
188                 return -1;
189 
190         if (readl(info->reg.gpmc_prefetch_control))
191                 return -EBUSY;
192 
193         /* Set the amount of bytes to be prefetched */
194         writel(u32_count, info->reg.gpmc_prefetch_config2);
195 
196         /* Set dma/mpu mode, the prefetch read / post write and
197          * enable the engine. Set which cs is has requested for.
198          */
199         val = ((cs << PREFETCH_CONFIG1_CS_SHIFT) |
200                 PREFETCH_FIFOTHRESHOLD(fifo_th) | ENABLE_PREFETCH |
201                 (dma_mode << DMA_MPU_MODE_SHIFT) | (0x1 & is_write));
202         writel(val, info->reg.gpmc_prefetch_config1);
203 
204         /*  Start the prefetch engine */
205         writel(0x1, info->reg.gpmc_prefetch_control);
206 
207         return 0;
208 }
209 
210 /**
211  * omap_prefetch_reset - disables and stops the prefetch engine
212  */
213 static int omap_prefetch_reset(int cs, struct omap_nand_info *info)
214 {
215         u32 config1;
216 
217         /* check if the same module/cs is trying to reset */
218         config1 = readl(info->reg.gpmc_prefetch_config1);
219         if (((config1 >> PREFETCH_CONFIG1_CS_SHIFT) & CS_MASK) != cs)
220                 return -EINVAL;
221 
222         /* Stop the PFPW engine */
223         writel(0x0, info->reg.gpmc_prefetch_control);
224 
225         /* Reset/disable the PFPW engine */
226         writel(0x0, info->reg.gpmc_prefetch_config1);
227 
228         return 0;
229 }
230 
231 /**
232  * omap_hwcontrol - hardware specific access to control-lines
233  * @mtd: MTD device structure
234  * @cmd: command to device
235  * @ctrl:
236  * NAND_NCE: bit 0 -> don't care
237  * NAND_CLE: bit 1 -> Command Latch
238  * NAND_ALE: bit 2 -> Address Latch
239  *
240  * NOTE: boards may use different bits for these!!
241  */
242 static void omap_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int ctrl)
243 {
244         struct omap_nand_info *info = container_of(mtd,
245                                         struct omap_nand_info, mtd);
246 
247         if (cmd != NAND_CMD_NONE) {
248                 if (ctrl & NAND_CLE)
249                         writeb(cmd, info->reg.gpmc_nand_command);
250 
251                 else if (ctrl & NAND_ALE)
252                         writeb(cmd, info->reg.gpmc_nand_address);
253 
254                 else /* NAND_NCE */
255                         writeb(cmd, info->reg.gpmc_nand_data);
256         }
257 }
258 
259 /**
260  * omap_read_buf8 - read data from NAND controller into buffer
261  * @mtd: MTD device structure
262  * @buf: buffer to store date
263  * @len: number of bytes to read
264  */
265 static void omap_read_buf8(struct mtd_info *mtd, u_char *buf, int len)
266 {
267         struct nand_chip *nand = mtd->priv;
268 
269         ioread8_rep(nand->IO_ADDR_R, buf, len);
270 }
271 
272 /**
273  * omap_write_buf8 - write buffer to NAND controller
274  * @mtd: MTD device structure
275  * @buf: data buffer
276  * @len: number of bytes to write
277  */
278 static void omap_write_buf8(struct mtd_info *mtd, const u_char *buf, int len)
279 {
280         struct omap_nand_info *info = container_of(mtd,
281                                                 struct omap_nand_info, mtd);
282         u_char *p = (u_char *)buf;
283         u32     status = 0;
284 
285         while (len--) {
286                 iowrite8(*p++, info->nand.IO_ADDR_W);
287                 /* wait until buffer is available for write */
288                 do {
289                         status = readl(info->reg.gpmc_status) &
290                                         STATUS_BUFF_EMPTY;
291                 } while (!status);
292         }
293 }
294 
295 /**
296  * omap_read_buf16 - read data from NAND controller into buffer
297  * @mtd: MTD device structure
298  * @buf: buffer to store date
299  * @len: number of bytes to read
300  */
301 static void omap_read_buf16(struct mtd_info *mtd, u_char *buf, int len)
302 {
303         struct nand_chip *nand = mtd->priv;
304 
305         ioread16_rep(nand->IO_ADDR_R, buf, len / 2);
306 }
307 
308 /**
309  * omap_write_buf16 - write buffer to NAND controller
310  * @mtd: MTD device structure
311  * @buf: data buffer
312  * @len: number of bytes to write
313  */
314 static void omap_write_buf16(struct mtd_info *mtd, const u_char * buf, int len)
315 {
316         struct omap_nand_info *info = container_of(mtd,
317                                                 struct omap_nand_info, mtd);
318         u16 *p = (u16 *) buf;
319         u32     status = 0;
320         /* FIXME try bursts of writesw() or DMA ... */
321         len >>= 1;
322 
323         while (len--) {
324                 iowrite16(*p++, info->nand.IO_ADDR_W);
325                 /* wait until buffer is available for write */
326                 do {
327                         status = readl(info->reg.gpmc_status) &
328                                         STATUS_BUFF_EMPTY;
329                 } while (!status);
330         }
331 }
332 
333 /**
334  * omap_read_buf_pref - read data from NAND controller into buffer
335  * @mtd: MTD device structure
336  * @buf: buffer to store date
337  * @len: number of bytes to read
338  */
339 static void omap_read_buf_pref(struct mtd_info *mtd, u_char *buf, int len)
340 {
341         struct omap_nand_info *info = container_of(mtd,
342                                                 struct omap_nand_info, mtd);
343         uint32_t r_count = 0;
344         int ret = 0;
345         u32 *p = (u32 *)buf;
346 
347         /* take care of subpage reads */
348         if (len % 4) {
349                 if (info->nand.options & NAND_BUSWIDTH_16)
350                         omap_read_buf16(mtd, buf, len % 4);
351                 else
352                         omap_read_buf8(mtd, buf, len % 4);
353                 p = (u32 *) (buf + len % 4);
354                 len -= len % 4;
355         }
356 
357         /* configure and start prefetch transfer */
358         ret = omap_prefetch_enable(info->gpmc_cs,
359                         PREFETCH_FIFOTHRESHOLD_MAX, 0x0, len, 0x0, info);
360         if (ret) {
361                 /* PFPW engine is busy, use cpu copy method */
362                 if (info->nand.options & NAND_BUSWIDTH_16)
363                         omap_read_buf16(mtd, (u_char *)p, len);
364                 else
365                         omap_read_buf8(mtd, (u_char *)p, len);
366         } else {
367                 do {
368                         r_count = readl(info->reg.gpmc_prefetch_status);
369                         r_count = PREFETCH_STATUS_FIFO_CNT(r_count);
370                         r_count = r_count >> 2;
371                         ioread32_rep(info->nand.IO_ADDR_R, p, r_count);
372                         p += r_count;
373                         len -= r_count << 2;
374                 } while (len);
375                 /* disable and stop the PFPW engine */
376                 omap_prefetch_reset(info->gpmc_cs, info);
377         }
378 }
379 
380 /**
381  * omap_write_buf_pref - write buffer to NAND controller
382  * @mtd: MTD device structure
383  * @buf: data buffer
384  * @len: number of bytes to write
385  */
386 static void omap_write_buf_pref(struct mtd_info *mtd,
387                                         const u_char *buf, int len)
388 {
389         struct omap_nand_info *info = container_of(mtd,
390                                                 struct omap_nand_info, mtd);
391         uint32_t w_count = 0;
392         int i = 0, ret = 0;
393         u16 *p = (u16 *)buf;
394         unsigned long tim, limit;
395         u32 val;
396 
397         /* take care of subpage writes */
398         if (len % 2 != 0) {
399                 writeb(*buf, info->nand.IO_ADDR_W);
400                 p = (u16 *)(buf + 1);
401                 len--;
402         }
403 
404         /*  configure and start prefetch transfer */
405         ret = omap_prefetch_enable(info->gpmc_cs,
406                         PREFETCH_FIFOTHRESHOLD_MAX, 0x0, len, 0x1, info);
407         if (ret) {
408                 /* PFPW engine is busy, use cpu copy method */
409                 if (info->nand.options & NAND_BUSWIDTH_16)
410                         omap_write_buf16(mtd, (u_char *)p, len);
411                 else
412                         omap_write_buf8(mtd, (u_char *)p, len);
413         } else {
414                 while (len) {
415                         w_count = readl(info->reg.gpmc_prefetch_status);
416                         w_count = PREFETCH_STATUS_FIFO_CNT(w_count);
417                         w_count = w_count >> 1;
418                         for (i = 0; (i < w_count) && len; i++, len -= 2)
419                                 iowrite16(*p++, info->nand.IO_ADDR_W);
420                 }
421                 /* wait for data to flushed-out before reset the prefetch */
422                 tim = 0;
423                 limit = (loops_per_jiffy *
424                                         msecs_to_jiffies(OMAP_NAND_TIMEOUT_MS));
425                 do {
426                         cpu_relax();
427                         val = readl(info->reg.gpmc_prefetch_status);
428                         val = PREFETCH_STATUS_COUNT(val);
429                 } while (val && (tim++ < limit));
430 
431                 /* disable and stop the PFPW engine */
432                 omap_prefetch_reset(info->gpmc_cs, info);
433         }
434 }
435 
436 /*
437  * omap_nand_dma_callback: callback on the completion of dma transfer
438  * @data: pointer to completion data structure
439  */
440 static void omap_nand_dma_callback(void *data)
441 {
442         complete((struct completion *) data);
443 }
444 
445 /*
446  * omap_nand_dma_transfer: configure and start dma transfer
447  * @mtd: MTD device structure
448  * @addr: virtual address in RAM of source/destination
449  * @len: number of data bytes to be transferred
450  * @is_write: flag for read/write operation
451  */
452 static inline int omap_nand_dma_transfer(struct mtd_info *mtd, void *addr,
453                                         unsigned int len, int is_write)
454 {
455         struct omap_nand_info *info = container_of(mtd,
456                                         struct omap_nand_info, mtd);
457         struct dma_async_tx_descriptor *tx;
458         enum dma_data_direction dir = is_write ? DMA_TO_DEVICE :
459                                                         DMA_FROM_DEVICE;
460         struct scatterlist sg;
461         unsigned long tim, limit;
462         unsigned n;
463         int ret;
464         u32 val;
465 
466         if (addr >= high_memory) {
467                 struct page *p1;
468 
469                 if (((size_t)addr & PAGE_MASK) !=
470                         ((size_t)(addr + len - 1) & PAGE_MASK))
471                         goto out_copy;
472                 p1 = vmalloc_to_page(addr);
473                 if (!p1)
474                         goto out_copy;
475                 addr = page_address(p1) + ((size_t)addr & ~PAGE_MASK);
476         }
477 
478         sg_init_one(&sg, addr, len);
479         n = dma_map_sg(info->dma->device->dev, &sg, 1, dir);
480         if (n == 0) {
481                 dev_err(&info->pdev->dev,
482                         "Couldn't DMA map a %d byte buffer\n", len);
483                 goto out_copy;
484         }
485 
486         tx = dmaengine_prep_slave_sg(info->dma, &sg, n,
487                 is_write ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM,
488                 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
489         if (!tx)
490                 goto out_copy_unmap;
491 
492         tx->callback = omap_nand_dma_callback;
493         tx->callback_param = &info->comp;
494         dmaengine_submit(tx);
495 
496         /*  configure and start prefetch transfer */
497         ret = omap_prefetch_enable(info->gpmc_cs,
498                 PREFETCH_FIFOTHRESHOLD_MAX, 0x1, len, is_write, info);
499         if (ret)
500                 /* PFPW engine is busy, use cpu copy method */
501                 goto out_copy_unmap;
502 
503         init_completion(&info->comp);
504         dma_async_issue_pending(info->dma);
505 
506         /* setup and start DMA using dma_addr */
507         wait_for_completion(&info->comp);
508         tim = 0;
509         limit = (loops_per_jiffy * msecs_to_jiffies(OMAP_NAND_TIMEOUT_MS));
510 
511         do {
512                 cpu_relax();
513                 val = readl(info->reg.gpmc_prefetch_status);
514                 val = PREFETCH_STATUS_COUNT(val);
515         } while (val && (tim++ < limit));
516 
517         /* disable and stop the PFPW engine */
518         omap_prefetch_reset(info->gpmc_cs, info);
519 
520         dma_unmap_sg(info->dma->device->dev, &sg, 1, dir);
521         return 0;
522 
523 out_copy_unmap:
524         dma_unmap_sg(info->dma->device->dev, &sg, 1, dir);
525 out_copy:
526         if (info->nand.options & NAND_BUSWIDTH_16)
527                 is_write == 0 ? omap_read_buf16(mtd, (u_char *) addr, len)
528                         : omap_write_buf16(mtd, (u_char *) addr, len);
529         else
530                 is_write == 0 ? omap_read_buf8(mtd, (u_char *) addr, len)
531                         : omap_write_buf8(mtd, (u_char *) addr, len);
532         return 0;
533 }
534 
535 /**
536  * omap_read_buf_dma_pref - read data from NAND controller into buffer
537  * @mtd: MTD device structure
538  * @buf: buffer to store date
539  * @len: number of bytes to read
540  */
541 static void omap_read_buf_dma_pref(struct mtd_info *mtd, u_char *buf, int len)
542 {
543         if (len <= mtd->oobsize)
544                 omap_read_buf_pref(mtd, buf, len);
545         else
546                 /* start transfer in DMA mode */
547                 omap_nand_dma_transfer(mtd, buf, len, 0x0);
548 }
549 
550 /**
551  * omap_write_buf_dma_pref - write buffer to NAND controller
552  * @mtd: MTD device structure
553  * @buf: data buffer
554  * @len: number of bytes to write
555  */
556 static void omap_write_buf_dma_pref(struct mtd_info *mtd,
557                                         const u_char *buf, int len)
558 {
559         if (len <= mtd->oobsize)
560                 omap_write_buf_pref(mtd, buf, len);
561         else
562                 /* start transfer in DMA mode */
563                 omap_nand_dma_transfer(mtd, (u_char *) buf, len, 0x1);
564 }
565 
566 /*
567  * omap_nand_irq - GPMC irq handler
568  * @this_irq: gpmc irq number
569  * @dev: omap_nand_info structure pointer is passed here
570  */
571 static irqreturn_t omap_nand_irq(int this_irq, void *dev)
572 {
573         struct omap_nand_info *info = (struct omap_nand_info *) dev;
574         u32 bytes;
575 
576         bytes = readl(info->reg.gpmc_prefetch_status);
577         bytes = PREFETCH_STATUS_FIFO_CNT(bytes);
578         bytes = bytes  & 0xFFFC; /* io in multiple of 4 bytes */
579         if (info->iomode == OMAP_NAND_IO_WRITE) { /* checks for write io */
580                 if (this_irq == info->gpmc_irq_count)
581                         goto done;
582 
583                 if (info->buf_len && (info->buf_len < bytes))
584                         bytes = info->buf_len;
585                 else if (!info->buf_len)
586                         bytes = 0;
587                 iowrite32_rep(info->nand.IO_ADDR_W,
588                                                 (u32 *)info->buf, bytes >> 2);
589                 info->buf = info->buf + bytes;
590                 info->buf_len -= bytes;
591 
592         } else {
593                 ioread32_rep(info->nand.IO_ADDR_R,
594                                                 (u32 *)info->buf, bytes >> 2);
595                 info->buf = info->buf + bytes;
596 
597                 if (this_irq == info->gpmc_irq_count)
598                         goto done;
599         }
600 
601         return IRQ_HANDLED;
602 
603 done:
604         complete(&info->comp);
605 
606         disable_irq_nosync(info->gpmc_irq_fifo);
607         disable_irq_nosync(info->gpmc_irq_count);
608 
609         return IRQ_HANDLED;
610 }
611 
612 /*
613  * omap_read_buf_irq_pref - read data from NAND controller into buffer
614  * @mtd: MTD device structure
615  * @buf: buffer to store date
616  * @len: number of bytes to read
617  */
618 static void omap_read_buf_irq_pref(struct mtd_info *mtd, u_char *buf, int len)
619 {
620         struct omap_nand_info *info = container_of(mtd,
621                                                 struct omap_nand_info, mtd);
622         int ret = 0;
623 
624         if (len <= mtd->oobsize) {
625                 omap_read_buf_pref(mtd, buf, len);
626                 return;
627         }
628 
629         info->iomode = OMAP_NAND_IO_READ;
630         info->buf = buf;
631         init_completion(&info->comp);
632 
633         /*  configure and start prefetch transfer */
634         ret = omap_prefetch_enable(info->gpmc_cs,
635                         PREFETCH_FIFOTHRESHOLD_MAX/2, 0x0, len, 0x0, info);
636         if (ret)
637                 /* PFPW engine is busy, use cpu copy method */
638                 goto out_copy;
639 
640         info->buf_len = len;
641 
642         enable_irq(info->gpmc_irq_count);
643         enable_irq(info->gpmc_irq_fifo);
644 
645         /* waiting for read to complete */
646         wait_for_completion(&info->comp);
647 
648         /* disable and stop the PFPW engine */
649         omap_prefetch_reset(info->gpmc_cs, info);
650         return;
651 
652 out_copy:
653         if (info->nand.options & NAND_BUSWIDTH_16)
654                 omap_read_buf16(mtd, buf, len);
655         else
656                 omap_read_buf8(mtd, buf, len);
657 }
658 
659 /*
660  * omap_write_buf_irq_pref - write buffer to NAND controller
661  * @mtd: MTD device structure
662  * @buf: data buffer
663  * @len: number of bytes to write
664  */
665 static void omap_write_buf_irq_pref(struct mtd_info *mtd,
666                                         const u_char *buf, int len)
667 {
668         struct omap_nand_info *info = container_of(mtd,
669                                                 struct omap_nand_info, mtd);
670         int ret = 0;
671         unsigned long tim, limit;
672         u32 val;
673 
674         if (len <= mtd->oobsize) {
675                 omap_write_buf_pref(mtd, buf, len);
676                 return;
677         }
678 
679         info->iomode = OMAP_NAND_IO_WRITE;
680         info->buf = (u_char *) buf;
681         init_completion(&info->comp);
682 
683         /* configure and start prefetch transfer : size=24 */
684         ret = omap_prefetch_enable(info->gpmc_cs,
685                 (PREFETCH_FIFOTHRESHOLD_MAX * 3) / 8, 0x0, len, 0x1, info);
686         if (ret)
687                 /* PFPW engine is busy, use cpu copy method */
688                 goto out_copy;
689 
690         info->buf_len = len;
691 
692         enable_irq(info->gpmc_irq_count);
693         enable_irq(info->gpmc_irq_fifo);
694 
695         /* waiting for write to complete */
696         wait_for_completion(&info->comp);
697 
698         /* wait for data to flushed-out before reset the prefetch */
699         tim = 0;
700         limit = (loops_per_jiffy *  msecs_to_jiffies(OMAP_NAND_TIMEOUT_MS));
701         do {
702                 val = readl(info->reg.gpmc_prefetch_status);
703                 val = PREFETCH_STATUS_COUNT(val);
704                 cpu_relax();
705         } while (val && (tim++ < limit));
706 
707         /* disable and stop the PFPW engine */
708         omap_prefetch_reset(info->gpmc_cs, info);
709         return;
710 
711 out_copy:
712         if (info->nand.options & NAND_BUSWIDTH_16)
713                 omap_write_buf16(mtd, buf, len);
714         else
715                 omap_write_buf8(mtd, buf, len);
716 }
717 
718 /**
719  * gen_true_ecc - This function will generate true ECC value
720  * @ecc_buf: buffer to store ecc code
721  *
722  * This generated true ECC value can be used when correcting
723  * data read from NAND flash memory core
724  */
725 static void gen_true_ecc(u8 *ecc_buf)
726 {
727         u32 tmp = ecc_buf[0] | (ecc_buf[1] << 16) |
728                 ((ecc_buf[2] & 0xF0) << 20) | ((ecc_buf[2] & 0x0F) << 8);
729 
730         ecc_buf[0] = ~(P64o(tmp) | P64e(tmp) | P32o(tmp) | P32e(tmp) |
731                         P16o(tmp) | P16e(tmp) | P8o(tmp) | P8e(tmp));
732         ecc_buf[1] = ~(P1024o(tmp) | P1024e(tmp) | P512o(tmp) | P512e(tmp) |
733                         P256o(tmp) | P256e(tmp) | P128o(tmp) | P128e(tmp));
734         ecc_buf[2] = ~(P4o(tmp) | P4e(tmp) | P2o(tmp) | P2e(tmp) | P1o(tmp) |
735                         P1e(tmp) | P2048o(tmp) | P2048e(tmp));
736 }
737 
738 /**
739  * omap_compare_ecc - Detect (2 bits) and correct (1 bit) error in data
740  * @ecc_data1:  ecc code from nand spare area
741  * @ecc_data2:  ecc code from hardware register obtained from hardware ecc
742  * @page_data:  page data
743  *
744  * This function compares two ECC's and indicates if there is an error.
745  * If the error can be corrected it will be corrected to the buffer.
746  * If there is no error, %0 is returned. If there is an error but it
747  * was corrected, %1 is returned. Otherwise, %-1 is returned.
748  */
749 static int omap_compare_ecc(u8 *ecc_data1,      /* read from NAND memory */
750                             u8 *ecc_data2,      /* read from register */
751                             u8 *page_data)
752 {
753         uint    i;
754         u8      tmp0_bit[8], tmp1_bit[8], tmp2_bit[8];
755         u8      comp0_bit[8], comp1_bit[8], comp2_bit[8];
756         u8      ecc_bit[24];
757         u8      ecc_sum = 0;
758         u8      find_bit = 0;
759         uint    find_byte = 0;
760         int     isEccFF;
761 
762         isEccFF = ((*(u32 *)ecc_data1 & 0xFFFFFF) == 0xFFFFFF);
763 
764         gen_true_ecc(ecc_data1);
765         gen_true_ecc(ecc_data2);
766 
767         for (i = 0; i <= 2; i++) {
768                 *(ecc_data1 + i) = ~(*(ecc_data1 + i));
769                 *(ecc_data2 + i) = ~(*(ecc_data2 + i));
770         }
771 
772         for (i = 0; i < 8; i++) {
773                 tmp0_bit[i]     = *ecc_data1 % 2;
774                 *ecc_data1      = *ecc_data1 / 2;
775         }
776 
777         for (i = 0; i < 8; i++) {
778                 tmp1_bit[i]      = *(ecc_data1 + 1) % 2;
779                 *(ecc_data1 + 1) = *(ecc_data1 + 1) / 2;
780         }
781 
782         for (i = 0; i < 8; i++) {
783                 tmp2_bit[i]      = *(ecc_data1 + 2) % 2;
784                 *(ecc_data1 + 2) = *(ecc_data1 + 2) / 2;
785         }
786 
787         for (i = 0; i < 8; i++) {
788                 comp0_bit[i]     = *ecc_data2 % 2;
789                 *ecc_data2       = *ecc_data2 / 2;
790         }
791 
792         for (i = 0; i < 8; i++) {
793                 comp1_bit[i]     = *(ecc_data2 + 1) % 2;
794                 *(ecc_data2 + 1) = *(ecc_data2 + 1) / 2;
795         }
796 
797         for (i = 0; i < 8; i++) {
798                 comp2_bit[i]     = *(ecc_data2 + 2) % 2;
799                 *(ecc_data2 + 2) = *(ecc_data2 + 2) / 2;
800         }
801 
802         for (i = 0; i < 6; i++)
803                 ecc_bit[i] = tmp2_bit[i + 2] ^ comp2_bit[i + 2];
804 
805         for (i = 0; i < 8; i++)
806                 ecc_bit[i + 6] = tmp0_bit[i] ^ comp0_bit[i];
807 
808         for (i = 0; i < 8; i++)
809                 ecc_bit[i + 14] = tmp1_bit[i] ^ comp1_bit[i];
810 
811         ecc_bit[22] = tmp2_bit[0] ^ comp2_bit[0];
812         ecc_bit[23] = tmp2_bit[1] ^ comp2_bit[1];
813 
814         for (i = 0; i < 24; i++)
815                 ecc_sum += ecc_bit[i];
816 
817         switch (ecc_sum) {
818         case 0:
819                 /* Not reached because this function is not called if
820                  *  ECC values are equal
821                  */
822                 return 0;
823 
824         case 1:
825                 /* Uncorrectable error */
826                 pr_debug("ECC UNCORRECTED_ERROR 1\n");
827                 return -1;
828 
829         case 11:
830                 /* UN-Correctable error */
831                 pr_debug("ECC UNCORRECTED_ERROR B\n");
832                 return -1;
833 
834         case 12:
835                 /* Correctable error */
836                 find_byte = (ecc_bit[23] << 8) +
837                             (ecc_bit[21] << 7) +
838                             (ecc_bit[19] << 6) +
839                             (ecc_bit[17] << 5) +
840                             (ecc_bit[15] << 4) +
841                             (ecc_bit[13] << 3) +
842                             (ecc_bit[11] << 2) +
843                             (ecc_bit[9]  << 1) +
844                             ecc_bit[7];
845 
846                 find_bit = (ecc_bit[5] << 2) + (ecc_bit[3] << 1) + ecc_bit[1];
847 
848                 pr_debug("Correcting single bit ECC error at offset: "
849                                 "%d, bit: %d\n", find_byte, find_bit);
850 
851                 page_data[find_byte] ^= (1 << find_bit);
852 
853                 return 1;
854         default:
855                 if (isEccFF) {
856                         if (ecc_data2[0] == 0 &&
857                             ecc_data2[1] == 0 &&
858                             ecc_data2[2] == 0)
859                                 return 0;
860                 }
861                 pr_debug("UNCORRECTED_ERROR default\n");
862                 return -1;
863         }
864 }
865 
866 /**
867  * omap_correct_data - Compares the ECC read with HW generated ECC
868  * @mtd: MTD device structure
869  * @dat: page data
870  * @read_ecc: ecc read from nand flash
871  * @calc_ecc: ecc read from HW ECC registers
872  *
873  * Compares the ecc read from nand spare area with ECC registers values
874  * and if ECC's mismatched, it will call 'omap_compare_ecc' for error
875  * detection and correction. If there are no errors, %0 is returned. If
876  * there were errors and all of the errors were corrected, the number of
877  * corrected errors is returned. If uncorrectable errors exist, %-1 is
878  * returned.
879  */
880 static int omap_correct_data(struct mtd_info *mtd, u_char *dat,
881                                 u_char *read_ecc, u_char *calc_ecc)
882 {
883         struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
884                                                         mtd);
885         int blockCnt = 0, i = 0, ret = 0;
886         int stat = 0;
887 
888         /* Ex NAND_ECC_HW12_2048 */
889         if ((info->nand.ecc.mode == NAND_ECC_HW) &&
890                         (info->nand.ecc.size  == 2048))
891                 blockCnt = 4;
892         else
893                 blockCnt = 1;
894 
895         for (i = 0; i < blockCnt; i++) {
896                 if (memcmp(read_ecc, calc_ecc, 3) != 0) {
897                         ret = omap_compare_ecc(read_ecc, calc_ecc, dat);
898                         if (ret < 0)
899                                 return ret;
900                         /* keep track of the number of corrected errors */
901                         stat += ret;
902                 }
903                 read_ecc += 3;
904                 calc_ecc += 3;
905                 dat      += 512;
906         }
907         return stat;
908 }
909 
910 /**
911  * omap_calcuate_ecc - Generate non-inverted ECC bytes.
912  * @mtd: MTD device structure
913  * @dat: The pointer to data on which ecc is computed
914  * @ecc_code: The ecc_code buffer
915  *
916  * Using noninverted ECC can be considered ugly since writing a blank
917  * page ie. padding will clear the ECC bytes. This is no problem as long
918  * nobody is trying to write data on the seemingly unused page. Reading
919  * an erased page will produce an ECC mismatch between generated and read
920  * ECC bytes that has to be dealt with separately.
921  */
922 static int omap_calculate_ecc(struct mtd_info *mtd, const u_char *dat,
923                                 u_char *ecc_code)
924 {
925         struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
926                                                         mtd);
927         u32 val;
928 
929         val = readl(info->reg.gpmc_ecc_config);
930         if (((val >> ECC_CONFIG_CS_SHIFT)  & ~CS_MASK) != info->gpmc_cs)
931                 return -EINVAL;
932 
933         /* read ecc result */
934         val = readl(info->reg.gpmc_ecc1_result);
935         *ecc_code++ = val;          /* P128e, ..., P1e */
936         *ecc_code++ = val >> 16;    /* P128o, ..., P1o */
937         /* P2048o, P1024o, P512o, P256o, P2048e, P1024e, P512e, P256e */
938         *ecc_code++ = ((val >> 8) & 0x0f) | ((val >> 20) & 0xf0);
939 
940         return 0;
941 }
942 
943 /**
944  * omap_enable_hwecc - This function enables the hardware ecc functionality
945  * @mtd: MTD device structure
946  * @mode: Read/Write mode
947  */
948 static void omap_enable_hwecc(struct mtd_info *mtd, int mode)
949 {
950         struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
951                                                         mtd);
952         struct nand_chip *chip = mtd->priv;
953         unsigned int dev_width = (chip->options & NAND_BUSWIDTH_16) ? 1 : 0;
954         u32 val;
955 
956         /* clear ecc and enable bits */
957         val = ECCCLEAR | ECC1;
958         writel(val, info->reg.gpmc_ecc_control);
959 
960         /* program ecc and result sizes */
961         val = ((((info->nand.ecc.size >> 1) - 1) << ECCSIZE1_SHIFT) |
962                          ECC1RESULTSIZE);
963         writel(val, info->reg.gpmc_ecc_size_config);
964 
965         switch (mode) {
966         case NAND_ECC_READ:
967         case NAND_ECC_WRITE:
968                 writel(ECCCLEAR | ECC1, info->reg.gpmc_ecc_control);
969                 break;
970         case NAND_ECC_READSYN:
971                 writel(ECCCLEAR, info->reg.gpmc_ecc_control);
972                 break;
973         default:
974                 dev_info(&info->pdev->dev,
975                         "error: unrecognized Mode[%d]!\n", mode);
976                 break;
977         }
978 
979         /* (ECC 16 or 8 bit col) | ( CS  )  | ECC Enable */
980         val = (dev_width << 7) | (info->gpmc_cs << 1) | (0x1);
981         writel(val, info->reg.gpmc_ecc_config);
982 }
983 
984 /**
985  * omap_wait - wait until the command is done
986  * @mtd: MTD device structure
987  * @chip: NAND Chip structure
988  *
989  * Wait function is called during Program and erase operations and
990  * the way it is called from MTD layer, we should wait till the NAND
991  * chip is ready after the programming/erase operation has completed.
992  *
993  * Erase can take up to 400ms and program up to 20ms according to
994  * general NAND and SmartMedia specs
995  */
996 static int omap_wait(struct mtd_info *mtd, struct nand_chip *chip)
997 {
998         struct nand_chip *this = mtd->priv;
999         struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
1000                                                         mtd);
1001         unsigned long timeo = jiffies;
1002         int status, state = this->state;
1003 
1004         if (state == FL_ERASING)
1005                 timeo += msecs_to_jiffies(400);
1006         else
1007                 timeo += msecs_to_jiffies(20);
1008 
1009         writeb(NAND_CMD_STATUS & 0xFF, info->reg.gpmc_nand_command);
1010         while (time_before(jiffies, timeo)) {
1011                 status = readb(info->reg.gpmc_nand_data);
1012                 if (status & NAND_STATUS_READY)
1013                         break;
1014                 cond_resched();
1015         }
1016 
1017         status = readb(info->reg.gpmc_nand_data);
1018         return status;
1019 }
1020 
1021 /**
1022  * omap_dev_ready - calls the platform specific dev_ready function
1023  * @mtd: MTD device structure
1024  */
1025 static int omap_dev_ready(struct mtd_info *mtd)
1026 {
1027         unsigned int val = 0;
1028         struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
1029                                                         mtd);
1030 
1031         val = readl(info->reg.gpmc_status);
1032 
1033         if ((val & 0x100) == 0x100) {
1034                 return 1;
1035         } else {
1036                 return 0;
1037         }
1038 }
1039 
1040 /**
1041  * omap_enable_hwecc_bch - Program GPMC to perform BCH ECC calculation
1042  * @mtd: MTD device structure
1043  * @mode: Read/Write mode
1044  *
1045  * When using BCH, sector size is hardcoded to 512 bytes.
1046  * Using wrapping mode 6 both for reading and writing if ELM module not uses
1047  * for error correction.
1048  * On writing,
1049  * eccsize0 = 0  (no additional protected byte in spare area)
1050  * eccsize1 = 32 (skip 32 nibbles = 16 bytes per sector in spare area)
1051  */
1052 static void __maybe_unused omap_enable_hwecc_bch(struct mtd_info *mtd, int mode)
1053 {
1054         unsigned int bch_type;
1055         unsigned int dev_width, nsectors;
1056         struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
1057                                                    mtd);
1058         enum omap_ecc ecc_opt = info->ecc_opt;
1059         struct nand_chip *chip = mtd->priv;
1060         u32 val, wr_mode;
1061         unsigned int ecc_size1, ecc_size0;
1062 
1063         /* GPMC configurations for calculating ECC */
1064         switch (ecc_opt) {
1065         case OMAP_ECC_BCH4_CODE_HW_DETECTION_SW:
1066                 bch_type = 0;
1067                 nsectors = 1;
1068                 if (mode == NAND_ECC_READ) {
1069                         wr_mode   = BCH_WRAPMODE_6;
1070                         ecc_size0 = BCH_ECC_SIZE0;
1071                         ecc_size1 = BCH_ECC_SIZE1;
1072                 } else {
1073                         wr_mode   = BCH_WRAPMODE_6;
1074                         ecc_size0 = BCH_ECC_SIZE0;
1075                         ecc_size1 = BCH_ECC_SIZE1;
1076                 }
1077                 break;
1078         case OMAP_ECC_BCH4_CODE_HW:
1079                 bch_type = 0;
1080                 nsectors = chip->ecc.steps;
1081                 if (mode == NAND_ECC_READ) {
1082                         wr_mode   = BCH_WRAPMODE_1;
1083                         ecc_size0 = BCH4R_ECC_SIZE0;
1084                         ecc_size1 = BCH4R_ECC_SIZE1;
1085                 } else {
1086                         wr_mode   = BCH_WRAPMODE_6;
1087                         ecc_size0 = BCH_ECC_SIZE0;
1088                         ecc_size1 = BCH_ECC_SIZE1;
1089                 }
1090                 break;
1091         case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW:
1092                 bch_type = 1;
1093                 nsectors = 1;
1094                 if (mode == NAND_ECC_READ) {
1095                         wr_mode   = BCH_WRAPMODE_6;
1096                         ecc_size0 = BCH_ECC_SIZE0;
1097                         ecc_size1 = BCH_ECC_SIZE1;
1098                 } else {
1099                         wr_mode   = BCH_WRAPMODE_6;
1100                         ecc_size0 = BCH_ECC_SIZE0;
1101                         ecc_size1 = BCH_ECC_SIZE1;
1102                 }
1103                 break;
1104         case OMAP_ECC_BCH8_CODE_HW:
1105                 bch_type = 1;
1106                 nsectors = chip->ecc.steps;
1107                 if (mode == NAND_ECC_READ) {
1108                         wr_mode   = BCH_WRAPMODE_1;
1109                         ecc_size0 = BCH8R_ECC_SIZE0;
1110                         ecc_size1 = BCH8R_ECC_SIZE1;
1111                 } else {
1112                         wr_mode   = BCH_WRAPMODE_6;
1113                         ecc_size0 = BCH_ECC_SIZE0;
1114                         ecc_size1 = BCH_ECC_SIZE1;
1115                 }
1116                 break;
1117         default:
1118                 return;
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                (bch_type                 << 12) | /* BCH4/BCH8/BCH16 */
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 static u8  bch4_polynomial[] = {0x28, 0x13, 0xcc, 0x39, 0x96, 0xac, 0x7f};
1145 static u8  bch8_polynomial[] = {0xef, 0x51, 0x2e, 0x09, 0xed, 0x93, 0x9a, 0xc2,
1146                                 0x97, 0x79, 0xe5, 0x24, 0xb5};
1147 
1148 /**
1149  * omap_calculate_ecc_bch - Generate bytes of ECC bytes
1150  * @mtd:        MTD device structure
1151  * @dat:        The pointer to data on which ecc is computed
1152  * @ecc_code:   The ecc_code buffer
1153  *
1154  * Support calculating of BCH4/8 ecc vectors for the page
1155  */
1156 static int __maybe_unused omap_calculate_ecc_bch(struct mtd_info *mtd,
1157                                         const u_char *dat, u_char *ecc_calc)
1158 {
1159         struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
1160                                                    mtd);
1161         int eccbytes    = info->nand.ecc.bytes;
1162         struct gpmc_nand_regs   *gpmc_regs = &info->reg;
1163         u8 *ecc_code;
1164         unsigned long nsectors, bch_val1, bch_val2, bch_val3, bch_val4;
1165         int i;
1166 
1167         nsectors = ((readl(info->reg.gpmc_ecc_config) >> 4) & 0x7) + 1;
1168         for (i = 0; i < nsectors; i++) {
1169                 ecc_code = ecc_calc;
1170                 switch (info->ecc_opt) {
1171                 case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW:
1172                 case OMAP_ECC_BCH8_CODE_HW:
1173                         bch_val1 = readl(gpmc_regs->gpmc_bch_result0[i]);
1174                         bch_val2 = readl(gpmc_regs->gpmc_bch_result1[i]);
1175                         bch_val3 = readl(gpmc_regs->gpmc_bch_result2[i]);
1176                         bch_val4 = readl(gpmc_regs->gpmc_bch_result3[i]);
1177                         *ecc_code++ = (bch_val4 & 0xFF);
1178                         *ecc_code++ = ((bch_val3 >> 24) & 0xFF);
1179                         *ecc_code++ = ((bch_val3 >> 16) & 0xFF);
1180                         *ecc_code++ = ((bch_val3 >> 8) & 0xFF);
1181                         *ecc_code++ = (bch_val3 & 0xFF);
1182                         *ecc_code++ = ((bch_val2 >> 24) & 0xFF);
1183                         *ecc_code++ = ((bch_val2 >> 16) & 0xFF);
1184                         *ecc_code++ = ((bch_val2 >> 8) & 0xFF);
1185                         *ecc_code++ = (bch_val2 & 0xFF);
1186                         *ecc_code++ = ((bch_val1 >> 24) & 0xFF);
1187                         *ecc_code++ = ((bch_val1 >> 16) & 0xFF);
1188                         *ecc_code++ = ((bch_val1 >> 8) & 0xFF);
1189                         *ecc_code++ = (bch_val1 & 0xFF);
1190                         break;
1191                 case OMAP_ECC_BCH4_CODE_HW_DETECTION_SW:
1192                 case OMAP_ECC_BCH4_CODE_HW:
1193                         bch_val1 = readl(gpmc_regs->gpmc_bch_result0[i]);
1194                         bch_val2 = readl(gpmc_regs->gpmc_bch_result1[i]);
1195                         *ecc_code++ = ((bch_val2 >> 12) & 0xFF);
1196                         *ecc_code++ = ((bch_val2 >> 4) & 0xFF);
1197                         *ecc_code++ = ((bch_val2 & 0xF) << 4) |
1198                                 ((bch_val1 >> 28) & 0xF);
1199                         *ecc_code++ = ((bch_val1 >> 20) & 0xFF);
1200                         *ecc_code++ = ((bch_val1 >> 12) & 0xFF);
1201                         *ecc_code++ = ((bch_val1 >> 4) & 0xFF);
1202                         *ecc_code++ = ((bch_val1 & 0xF) << 4);
1203                         break;
1204                 default:
1205                         return -EINVAL;
1206                 }
1207 
1208                 /* ECC scheme specific syndrome customizations */
1209                 switch (info->ecc_opt) {
1210                 case OMAP_ECC_BCH4_CODE_HW_DETECTION_SW:
1211                         /* Add constant polynomial to remainder, so that
1212                          * ECC of blank pages results in 0x0 on reading back */
1213                         for (i = 0; i < eccbytes; i++)
1214                                 ecc_calc[i] ^= bch4_polynomial[i];
1215                         break;
1216                 case OMAP_ECC_BCH4_CODE_HW:
1217                         /* Set  8th ECC byte as 0x0 for ROM compatibility */
1218                         ecc_calc[eccbytes - 1] = 0x0;
1219                         break;
1220                 case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW:
1221                         /* Add constant polynomial to remainder, so that
1222                          * ECC of blank pages results in 0x0 on reading back */
1223                         for (i = 0; i < eccbytes; i++)
1224                                 ecc_calc[i] ^= bch8_polynomial[i];
1225                         break;
1226                 case OMAP_ECC_BCH8_CODE_HW:
1227                         /* Set 14th ECC byte as 0x0 for ROM compatibility */
1228                         ecc_calc[eccbytes - 1] = 0x0;
1229                         break;
1230                 default:
1231                         return -EINVAL;
1232                 }
1233 
1234         ecc_calc += eccbytes;
1235         }
1236 
1237         return 0;
1238 }
1239 
1240 /**
1241  * erased_sector_bitflips - count bit flips
1242  * @data:       data sector buffer
1243  * @oob:        oob buffer
1244  * @info:       omap_nand_info
1245  *
1246  * Check the bit flips in erased page falls below correctable level.
1247  * If falls below, report the page as erased with correctable bit
1248  * flip, else report as uncorrectable page.
1249  */
1250 static int erased_sector_bitflips(u_char *data, u_char *oob,
1251                 struct omap_nand_info *info)
1252 {
1253         int flip_bits = 0, i;
1254 
1255         for (i = 0; i < info->nand.ecc.size; i++) {
1256                 flip_bits += hweight8(~data[i]);
1257                 if (flip_bits > info->nand.ecc.strength)
1258                         return 0;
1259         }
1260 
1261         for (i = 0; i < info->nand.ecc.bytes - 1; i++) {
1262                 flip_bits += hweight8(~oob[i]);
1263                 if (flip_bits > info->nand.ecc.strength)
1264                         return 0;
1265         }
1266 
1267         /*
1268          * Bit flips falls in correctable level.
1269          * Fill data area with 0xFF
1270          */
1271         if (flip_bits) {
1272                 memset(data, 0xFF, info->nand.ecc.size);
1273                 memset(oob, 0xFF, info->nand.ecc.bytes);
1274         }
1275 
1276         return flip_bits;
1277 }
1278 
1279 #ifdef CONFIG_MTD_NAND_OMAP_BCH
1280 /**
1281  * omap_elm_correct_data - corrects page data area in case error reported
1282  * @mtd:        MTD device structure
1283  * @data:       page data
1284  * @read_ecc:   ecc read from nand flash
1285  * @calc_ecc:   ecc read from HW ECC registers
1286  *
1287  * Calculated ecc vector reported as zero in case of non-error pages.
1288  * In case of non-zero ecc vector, first filter out erased-pages, and
1289  * then process data via ELM to detect bit-flips.
1290  */
1291 static int omap_elm_correct_data(struct mtd_info *mtd, u_char *data,
1292                                 u_char *read_ecc, u_char *calc_ecc)
1293 {
1294         struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
1295                         mtd);
1296         struct nand_ecc_ctrl *ecc = &info->nand.ecc;
1297         int eccsteps = info->nand.ecc.steps;
1298         int i , j, stat = 0;
1299         int eccflag, actual_eccbytes;
1300         struct elm_errorvec err_vec[ERROR_VECTOR_MAX];
1301         u_char *ecc_vec = calc_ecc;
1302         u_char *spare_ecc = read_ecc;
1303         u_char *erased_ecc_vec;
1304         u_char *buf;
1305         int bitflip_count;
1306         bool is_error_reported = false;
1307         u32 bit_pos, byte_pos, error_max, pos;
1308         int err;
1309 
1310         switch (info->ecc_opt) {
1311         case OMAP_ECC_BCH4_CODE_HW:
1312                 /* omit  7th ECC byte reserved for ROM code compatibility */
1313                 actual_eccbytes = ecc->bytes - 1;
1314                 erased_ecc_vec = bch4_vector;
1315                 break;
1316         case OMAP_ECC_BCH8_CODE_HW:
1317                 /* omit 14th ECC byte reserved for ROM code compatibility */
1318                 actual_eccbytes = ecc->bytes - 1;
1319                 erased_ecc_vec = bch8_vector;
1320                 break;
1321         default:
1322                 pr_err("invalid driver configuration\n");
1323                 return -EINVAL;
1324         }
1325 
1326         /* Initialize elm error vector to zero */
1327         memset(err_vec, 0, sizeof(err_vec));
1328 
1329         for (i = 0; i < eccsteps ; i++) {
1330                 eccflag = 0;    /* initialize eccflag */
1331 
1332                 /*
1333                  * Check any error reported,
1334                  * In case of error, non zero ecc reported.
1335                  */
1336                 for (j = 0; j < actual_eccbytes; j++) {
1337                         if (calc_ecc[j] != 0) {
1338                                 eccflag = 1; /* non zero ecc, error present */
1339                                 break;
1340                         }
1341                 }
1342 
1343                 if (eccflag == 1) {
1344                         if (memcmp(calc_ecc, erased_ecc_vec,
1345                                                 actual_eccbytes) == 0) {
1346                                 /*
1347                                  * calc_ecc[] matches pattern for ECC(all 0xff)
1348                                  * so this is definitely an erased-page
1349                                  */
1350                         } else {
1351                                 buf = &data[info->nand.ecc.size * i];
1352                                 /*
1353                                  * count number of 0-bits in read_buf.
1354                                  * This check can be removed once a similar
1355                                  * check is introduced in generic NAND driver
1356                                  */
1357                                 bitflip_count = erased_sector_bitflips(
1358                                                 buf, read_ecc, info);
1359                                 if (bitflip_count) {
1360                                         /*
1361                                          * number of 0-bits within ECC limits
1362                                          * So this may be an erased-page
1363                                          */
1364                                         stat += bitflip_count;
1365                                 } else {
1366                                         /*
1367                                          * Too many 0-bits. It may be a
1368                                          * - programmed-page, OR
1369                                          * - erased-page with many bit-flips
1370                                          * So this page requires check by ELM
1371                                          */
1372                                         err_vec[i].error_reported = true;
1373                                         is_error_reported = true;
1374                                 }
1375                         }
1376                 }
1377 
1378                 /* Update the ecc vector */
1379                 calc_ecc += ecc->bytes;
1380                 read_ecc += ecc->bytes;
1381         }
1382 
1383         /* Check if any error reported */
1384         if (!is_error_reported)
1385                 return 0;
1386 
1387         /* Decode BCH error using ELM module */
1388         elm_decode_bch_error_page(info->elm_dev, ecc_vec, err_vec);
1389 
1390         err = 0;
1391         for (i = 0; i < eccsteps; i++) {
1392                 if (err_vec[i].error_uncorrectable) {
1393                         pr_err("nand: uncorrectable bit-flips found\n");
1394                         err = -EBADMSG;
1395                 } else if (err_vec[i].error_reported) {
1396                         for (j = 0; j < err_vec[i].error_count; j++) {
1397                                 switch (info->ecc_opt) {
1398                                 case OMAP_ECC_BCH4_CODE_HW:
1399                                         /* Add 4 bits to take care of padding */
1400                                         pos = err_vec[i].error_loc[j] +
1401                                                 BCH4_BIT_PAD;
1402                                         break;
1403                                 case OMAP_ECC_BCH8_CODE_HW:
1404                                         pos = err_vec[i].error_loc[j];
1405                                         break;
1406                                 default:
1407                                         return -EINVAL;
1408                                 }
1409                                 error_max = (ecc->size + actual_eccbytes) * 8;
1410                                 /* Calculate bit position of error */
1411                                 bit_pos = pos % 8;
1412 
1413                                 /* Calculate byte position of error */
1414                                 byte_pos = (error_max - pos - 1) / 8;
1415 
1416                                 if (pos < error_max) {
1417                                         if (byte_pos < 512) {
1418                                                 pr_debug("bitflip@dat[%d]=%x\n",
1419                                                      byte_pos, data[byte_pos]);
1420                                                 data[byte_pos] ^= 1 << bit_pos;
1421                                         } else {
1422                                                 pr_debug("bitflip@oob[%d]=%x\n",
1423                                                         (byte_pos - 512),
1424                                                      spare_ecc[byte_pos - 512]);
1425                                                 spare_ecc[byte_pos - 512] ^=
1426                                                         1 << bit_pos;
1427                                         }
1428                                 } else {
1429                                         pr_err("invalid bit-flip @ %d:%d\n",
1430                                                          byte_pos, bit_pos);
1431                                         err = -EBADMSG;
1432                                 }
1433                         }
1434                 }
1435 
1436                 /* Update number of correctable errors */
1437                 stat += err_vec[i].error_count;
1438 
1439                 /* Update page data with sector size */
1440                 data += ecc->size;
1441                 spare_ecc += ecc->bytes;
1442         }
1443 
1444         return (err) ? err : stat;
1445 }
1446 
1447 /**
1448  * omap_write_page_bch - BCH ecc based write page function for entire page
1449  * @mtd:                mtd info structure
1450  * @chip:               nand chip info structure
1451  * @buf:                data buffer
1452  * @oob_required:       must write chip->oob_poi to OOB
1453  *
1454  * Custom write page method evolved to support multi sector writing in one shot
1455  */
1456 static int omap_write_page_bch(struct mtd_info *mtd, struct nand_chip *chip,
1457                                   const uint8_t *buf, int oob_required)
1458 {
1459         int i;
1460         uint8_t *ecc_calc = chip->buffers->ecccalc;
1461         uint32_t *eccpos = chip->ecc.layout->eccpos;
1462 
1463         /* Enable GPMC ecc engine */
1464         chip->ecc.hwctl(mtd, NAND_ECC_WRITE);
1465 
1466         /* Write data */
1467         chip->write_buf(mtd, buf, mtd->writesize);
1468 
1469         /* Update ecc vector from GPMC result registers */
1470         chip->ecc.calculate(mtd, buf, &ecc_calc[0]);
1471 
1472         for (i = 0; i < chip->ecc.total; i++)
1473                 chip->oob_poi[eccpos[i]] = ecc_calc[i];
1474 
1475         /* Write ecc vector to OOB area */
1476         chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
1477         return 0;
1478 }
1479 
1480 /**
1481  * omap_read_page_bch - BCH ecc based page read function for entire page
1482  * @mtd:                mtd info structure
1483  * @chip:               nand chip info structure
1484  * @buf:                buffer to store read data
1485  * @oob_required:       caller requires OOB data read to chip->oob_poi
1486  * @page:               page number to read
1487  *
1488  * For BCH ecc scheme, GPMC used for syndrome calculation and ELM module
1489  * used for error correction.
1490  * Custom method evolved to support ELM error correction & multi sector
1491  * reading. On reading page data area is read along with OOB data with
1492  * ecc engine enabled. ecc vector updated after read of OOB data.
1493  * For non error pages ecc vector reported as zero.
1494  */
1495 static int omap_read_page_bch(struct mtd_info *mtd, struct nand_chip *chip,
1496                                 uint8_t *buf, int oob_required, int page)
1497 {
1498         uint8_t *ecc_calc = chip->buffers->ecccalc;
1499         uint8_t *ecc_code = chip->buffers->ecccode;
1500         uint32_t *eccpos = chip->ecc.layout->eccpos;
1501         uint8_t *oob = &chip->oob_poi[eccpos[0]];
1502         uint32_t oob_pos = mtd->writesize + chip->ecc.layout->eccpos[0];
1503         int stat;
1504         unsigned int max_bitflips = 0;
1505 
1506         /* Enable GPMC ecc engine */
1507         chip->ecc.hwctl(mtd, NAND_ECC_READ);
1508 
1509         /* Read data */
1510         chip->read_buf(mtd, buf, mtd->writesize);
1511 
1512         /* Read oob bytes */
1513         chip->cmdfunc(mtd, NAND_CMD_RNDOUT, oob_pos, -1);
1514         chip->read_buf(mtd, oob, chip->ecc.total);
1515 
1516         /* Calculate ecc bytes */
1517         chip->ecc.calculate(mtd, buf, ecc_calc);
1518 
1519         memcpy(ecc_code, &chip->oob_poi[eccpos[0]], chip->ecc.total);
1520 
1521         stat = chip->ecc.correct(mtd, buf, ecc_code, ecc_calc);
1522 
1523         if (stat < 0) {
1524                 mtd->ecc_stats.failed++;
1525         } else {
1526                 mtd->ecc_stats.corrected += stat;
1527                 max_bitflips = max_t(unsigned int, max_bitflips, stat);
1528         }
1529 
1530         return max_bitflips;
1531 }
1532 
1533 /**
1534  * is_elm_present - checks for presence of ELM module by scanning DT nodes
1535  * @omap_nand_info: NAND device structure containing platform data
1536  * @bch_type: 0x0=BCH4, 0x1=BCH8, 0x2=BCH16
1537  */
1538 static int is_elm_present(struct omap_nand_info *info,
1539                         struct device_node *elm_node, enum bch_ecc bch_type)
1540 {
1541         struct platform_device *pdev;
1542         struct nand_ecc_ctrl *ecc = &info->nand.ecc;
1543         int err;
1544         /* check whether elm-id is passed via DT */
1545         if (!elm_node) {
1546                 pr_err("nand: error: ELM DT node not found\n");
1547                 return -ENODEV;
1548         }
1549         pdev = of_find_device_by_node(elm_node);
1550         /* check whether ELM device is registered */
1551         if (!pdev) {
1552                 pr_err("nand: error: ELM device not found\n");
1553                 return -ENODEV;
1554         }
1555         /* ELM module available, now configure it */
1556         info->elm_dev = &pdev->dev;
1557         err = elm_config(info->elm_dev, bch_type,
1558                 (info->mtd.writesize / ecc->size), ecc->size, ecc->bytes);
1559 
1560         return err;
1561 }
1562 #endif /* CONFIG_MTD_NAND_ECC_BCH */
1563 
1564 static int omap_nand_probe(struct platform_device *pdev)
1565 {
1566         struct omap_nand_info           *info;
1567         struct omap_nand_platform_data  *pdata;
1568         struct mtd_info                 *mtd;
1569         struct nand_chip                *nand_chip;
1570         struct nand_ecclayout           *ecclayout;
1571         int                             err;
1572         int                             i;
1573         dma_cap_mask_t                  mask;
1574         unsigned                        sig;
1575         unsigned                        oob_index;
1576         struct resource                 *res;
1577         struct mtd_part_parser_data     ppdata = {};
1578 
1579         pdata = dev_get_platdata(&pdev->dev);
1580         if (pdata == NULL) {
1581                 dev_err(&pdev->dev, "platform data missing\n");
1582                 return -ENODEV;
1583         }
1584 
1585         info = devm_kzalloc(&pdev->dev, sizeof(struct omap_nand_info),
1586                                 GFP_KERNEL);
1587         if (!info)
1588                 return -ENOMEM;
1589 
1590         platform_set_drvdata(pdev, info);
1591 
1592         spin_lock_init(&info->controller.lock);
1593         init_waitqueue_head(&info->controller.wq);
1594 
1595         info->pdev              = pdev;
1596         info->gpmc_cs           = pdata->cs;
1597         info->reg               = pdata->reg;
1598         info->of_node           = pdata->of_node;
1599         info->ecc_opt           = pdata->ecc_opt;
1600         mtd                     = &info->mtd;
1601         mtd->priv               = &info->nand;
1602         mtd->name               = dev_name(&pdev->dev);
1603         mtd->owner              = THIS_MODULE;
1604         nand_chip               = &info->nand;
1605         nand_chip->ecc.priv     = NULL;
1606         nand_chip->options      |= NAND_SKIP_BBTSCAN;
1607 
1608         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1609         nand_chip->IO_ADDR_R = devm_ioremap_resource(&pdev->dev, res);
1610         if (IS_ERR(nand_chip->IO_ADDR_R))
1611                 return PTR_ERR(nand_chip->IO_ADDR_R);
1612 
1613         info->phys_base = res->start;
1614 
1615         nand_chip->controller = &info->controller;
1616 
1617         nand_chip->IO_ADDR_W = nand_chip->IO_ADDR_R;
1618         nand_chip->cmd_ctrl  = omap_hwcontrol;
1619 
1620         /*
1621          * If RDY/BSY line is connected to OMAP then use the omap ready
1622          * function and the generic nand_wait function which reads the status
1623          * register after monitoring the RDY/BSY line. Otherwise use a standard
1624          * chip delay which is slightly more than tR (AC Timing) of the NAND
1625          * device and read status register until you get a failure or success
1626          */
1627         if (pdata->dev_ready) {
1628                 nand_chip->dev_ready = omap_dev_ready;
1629                 nand_chip->chip_delay = 0;
1630         } else {
1631                 nand_chip->waitfunc = omap_wait;
1632                 nand_chip->chip_delay = 50;
1633         }
1634 
1635         /* scan NAND device connected to chip controller */
1636         nand_chip->options |= pdata->devsize & NAND_BUSWIDTH_16;
1637         if (nand_scan_ident(mtd, 1, NULL)) {
1638                 pr_err("nand device scan failed, may be bus-width mismatch\n");
1639                 err = -ENXIO;
1640                 goto return_error;
1641         }
1642 
1643         /* check for small page devices */
1644         if ((mtd->oobsize < 64) && (pdata->ecc_opt != OMAP_ECC_HAM1_CODE_HW)) {
1645                 pr_err("small page devices are not supported\n");
1646                 err = -EINVAL;
1647                 goto return_error;
1648         }
1649 
1650         /* re-populate low-level callbacks based on xfer modes */
1651         switch (pdata->xfer_type) {
1652         case NAND_OMAP_PREFETCH_POLLED:
1653                 nand_chip->read_buf   = omap_read_buf_pref;
1654                 nand_chip->write_buf  = omap_write_buf_pref;
1655                 break;
1656 
1657         case NAND_OMAP_POLLED:
1658                 /* Use nand_base defaults for {read,write}_buf */
1659                 break;
1660 
1661         case NAND_OMAP_PREFETCH_DMA:
1662                 dma_cap_zero(mask);
1663                 dma_cap_set(DMA_SLAVE, mask);
1664                 sig = OMAP24XX_DMA_GPMC;
1665                 info->dma = dma_request_channel(mask, omap_dma_filter_fn, &sig);
1666                 if (!info->dma) {
1667                         dev_err(&pdev->dev, "DMA engine request failed\n");
1668                         err = -ENXIO;
1669                         goto return_error;
1670                 } else {
1671                         struct dma_slave_config cfg;
1672 
1673                         memset(&cfg, 0, sizeof(cfg));
1674                         cfg.src_addr = info->phys_base;
1675                         cfg.dst_addr = info->phys_base;
1676                         cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1677                         cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1678                         cfg.src_maxburst = 16;
1679                         cfg.dst_maxburst = 16;
1680                         err = dmaengine_slave_config(info->dma, &cfg);
1681                         if (err) {
1682                                 dev_err(&pdev->dev, "DMA engine slave config failed: %d\n",
1683                                         err);
1684                                 goto return_error;
1685                         }
1686                         nand_chip->read_buf   = omap_read_buf_dma_pref;
1687                         nand_chip->write_buf  = omap_write_buf_dma_pref;
1688                 }
1689                 break;
1690 
1691         case NAND_OMAP_PREFETCH_IRQ:
1692                 info->gpmc_irq_fifo = platform_get_irq(pdev, 0);
1693                 if (info->gpmc_irq_fifo <= 0) {
1694                         dev_err(&pdev->dev, "error getting fifo irq\n");
1695                         err = -ENODEV;
1696                         goto return_error;
1697                 }
1698                 err = devm_request_irq(&pdev->dev, info->gpmc_irq_fifo,
1699                                         omap_nand_irq, IRQF_SHARED,
1700                                         "gpmc-nand-fifo", info);
1701                 if (err) {
1702                         dev_err(&pdev->dev, "requesting irq(%d) error:%d",
1703                                                 info->gpmc_irq_fifo, err);
1704                         info->gpmc_irq_fifo = 0;
1705                         goto return_error;
1706                 }
1707 
1708                 info->gpmc_irq_count = platform_get_irq(pdev, 1);
1709                 if (info->gpmc_irq_count <= 0) {
1710                         dev_err(&pdev->dev, "error getting count irq\n");
1711                         err = -ENODEV;
1712                         goto return_error;
1713                 }
1714                 err = devm_request_irq(&pdev->dev, info->gpmc_irq_count,
1715                                         omap_nand_irq, IRQF_SHARED,
1716                                         "gpmc-nand-count", info);
1717                 if (err) {
1718                         dev_err(&pdev->dev, "requesting irq(%d) error:%d",
1719                                                 info->gpmc_irq_count, err);
1720                         info->gpmc_irq_count = 0;
1721                         goto return_error;
1722                 }
1723 
1724                 nand_chip->read_buf  = omap_read_buf_irq_pref;
1725                 nand_chip->write_buf = omap_write_buf_irq_pref;
1726 
1727                 break;
1728 
1729         default:
1730                 dev_err(&pdev->dev,
1731                         "xfer_type(%d) not supported!\n", pdata->xfer_type);
1732                 err = -EINVAL;
1733                 goto return_error;
1734         }
1735 
1736         /* populate MTD interface based on ECC scheme */
1737         nand_chip->ecc.layout   = &omap_oobinfo;
1738         ecclayout               = &omap_oobinfo;
1739         switch (info->ecc_opt) {
1740         case OMAP_ECC_HAM1_CODE_HW:
1741                 pr_info("nand: using OMAP_ECC_HAM1_CODE_HW\n");
1742                 nand_chip->ecc.mode             = NAND_ECC_HW;
1743                 nand_chip->ecc.bytes            = 3;
1744                 nand_chip->ecc.size             = 512;
1745                 nand_chip->ecc.strength         = 1;
1746                 nand_chip->ecc.calculate        = omap_calculate_ecc;
1747                 nand_chip->ecc.hwctl            = omap_enable_hwecc;
1748                 nand_chip->ecc.correct          = omap_correct_data;
1749                 /* define ECC layout */
1750                 ecclayout->eccbytes             = nand_chip->ecc.bytes *
1751                                                         (mtd->writesize /
1752                                                         nand_chip->ecc.size);
1753                 if (nand_chip->options & NAND_BUSWIDTH_16)
1754                         oob_index               = BADBLOCK_MARKER_LENGTH;
1755                 else
1756                         oob_index               = 1;
1757                 for (i = 0; i < ecclayout->eccbytes; i++, oob_index++)
1758                         ecclayout->eccpos[i]    = oob_index;
1759                 /* no reserved-marker in ecclayout for this ecc-scheme */
1760                 ecclayout->oobfree->offset      =
1761                                 ecclayout->eccpos[ecclayout->eccbytes - 1] + 1;
1762                 break;
1763 
1764         case OMAP_ECC_BCH4_CODE_HW_DETECTION_SW:
1765 #ifdef CONFIG_MTD_NAND_ECC_BCH
1766                 pr_info("nand: using OMAP_ECC_BCH4_CODE_HW_DETECTION_SW\n");
1767                 nand_chip->ecc.mode             = NAND_ECC_HW;
1768                 nand_chip->ecc.size             = 512;
1769                 nand_chip->ecc.bytes            = 7;
1770                 nand_chip->ecc.strength         = 4;
1771                 nand_chip->ecc.hwctl            = omap_enable_hwecc_bch;
1772                 nand_chip->ecc.correct          = nand_bch_correct_data;
1773                 nand_chip->ecc.calculate        = omap_calculate_ecc_bch;
1774                 /* define ECC layout */
1775                 ecclayout->eccbytes             = nand_chip->ecc.bytes *
1776                                                         (mtd->writesize /
1777                                                         nand_chip->ecc.size);
1778                 oob_index                       = BADBLOCK_MARKER_LENGTH;
1779                 for (i = 0; i < ecclayout->eccbytes; i++, oob_index++) {
1780                         ecclayout->eccpos[i] = oob_index;
1781                         if (((i + 1) % nand_chip->ecc.bytes) == 0)
1782                                 oob_index++;
1783                 }
1784                 /* include reserved-marker in ecclayout->oobfree calculation */
1785                 ecclayout->oobfree->offset      = 1 +
1786                                 ecclayout->eccpos[ecclayout->eccbytes - 1] + 1;
1787                 /* software bch library is used for locating errors */
1788                 nand_chip->ecc.priv             = nand_bch_init(mtd,
1789                                                         nand_chip->ecc.size,
1790                                                         nand_chip->ecc.bytes,
1791                                                         &nand_chip->ecc.layout);
1792                 if (!nand_chip->ecc.priv) {
1793                         pr_err("nand: error: unable to use s/w BCH library\n");
1794                         err = -EINVAL;
1795                 }
1796                 break;
1797 #else
1798                 pr_err("nand: error: CONFIG_MTD_NAND_ECC_BCH not enabled\n");
1799                 err = -EINVAL;
1800                 goto return_error;
1801 #endif
1802 
1803         case OMAP_ECC_BCH4_CODE_HW:
1804 #ifdef CONFIG_MTD_NAND_OMAP_BCH
1805                 pr_info("nand: using OMAP_ECC_BCH4_CODE_HW ECC scheme\n");
1806                 nand_chip->ecc.mode             = NAND_ECC_HW;
1807                 nand_chip->ecc.size             = 512;
1808                 /* 14th bit is kept reserved for ROM-code compatibility */
1809                 nand_chip->ecc.bytes            = 7 + 1;
1810                 nand_chip->ecc.strength         = 4;
1811                 nand_chip->ecc.hwctl            = omap_enable_hwecc_bch;
1812                 nand_chip->ecc.correct          = omap_elm_correct_data;
1813                 nand_chip->ecc.calculate        = omap_calculate_ecc_bch;
1814                 nand_chip->ecc.read_page        = omap_read_page_bch;
1815                 nand_chip->ecc.write_page       = omap_write_page_bch;
1816                 /* define ECC layout */
1817                 ecclayout->eccbytes             = nand_chip->ecc.bytes *
1818                                                         (mtd->writesize /
1819                                                         nand_chip->ecc.size);
1820                 oob_index                       = BADBLOCK_MARKER_LENGTH;
1821                 for (i = 0; i < ecclayout->eccbytes; i++, oob_index++)
1822                         ecclayout->eccpos[i]    = oob_index;
1823                 /* reserved marker already included in ecclayout->eccbytes */
1824                 ecclayout->oobfree->offset      =
1825                                 ecclayout->eccpos[ecclayout->eccbytes - 1] + 1;
1826                 /* This ECC scheme requires ELM H/W block */
1827                 if (is_elm_present(info, pdata->elm_of_node, BCH4_ECC) < 0) {
1828                         pr_err("nand: error: could not initialize ELM\n");
1829                         err = -ENODEV;
1830                         goto return_error;
1831                 }
1832                 break;
1833 #else
1834                 pr_err("nand: error: CONFIG_MTD_NAND_OMAP_BCH not enabled\n");
1835                 err = -EINVAL;
1836                 goto return_error;
1837 #endif
1838 
1839         case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW:
1840 #ifdef CONFIG_MTD_NAND_ECC_BCH
1841                 pr_info("nand: using OMAP_ECC_BCH8_CODE_HW_DETECTION_SW\n");
1842                 nand_chip->ecc.mode             = NAND_ECC_HW;
1843                 nand_chip->ecc.size             = 512;
1844                 nand_chip->ecc.bytes            = 13;
1845                 nand_chip->ecc.strength         = 8;
1846                 nand_chip->ecc.hwctl            = omap_enable_hwecc_bch;
1847                 nand_chip->ecc.correct          = nand_bch_correct_data;
1848                 nand_chip->ecc.calculate        = omap_calculate_ecc_bch;
1849                 /* define ECC layout */
1850                 ecclayout->eccbytes             = nand_chip->ecc.bytes *
1851                                                         (mtd->writesize /
1852                                                         nand_chip->ecc.size);
1853                 oob_index                       = BADBLOCK_MARKER_LENGTH;
1854                 for (i = 0; i < ecclayout->eccbytes; i++, oob_index++) {
1855                         ecclayout->eccpos[i] = oob_index;
1856                         if (((i + 1) % nand_chip->ecc.bytes) == 0)
1857                                 oob_index++;
1858                 }
1859                 /* include reserved-marker in ecclayout->oobfree calculation */
1860                 ecclayout->oobfree->offset      = 1 +
1861                                 ecclayout->eccpos[ecclayout->eccbytes - 1] + 1;
1862                 /* software bch library is used for locating errors */
1863                 nand_chip->ecc.priv             = nand_bch_init(mtd,
1864                                                         nand_chip->ecc.size,
1865                                                         nand_chip->ecc.bytes,
1866                                                         &nand_chip->ecc.layout);
1867                 if (!nand_chip->ecc.priv) {
1868                         pr_err("nand: error: unable to use s/w BCH library\n");
1869                         err = -EINVAL;
1870                         goto return_error;
1871                 }
1872                 break;
1873 #else
1874                 pr_err("nand: error: CONFIG_MTD_NAND_ECC_BCH not enabled\n");
1875                 err = -EINVAL;
1876                 goto return_error;
1877 #endif
1878 
1879         case OMAP_ECC_BCH8_CODE_HW:
1880 #ifdef CONFIG_MTD_NAND_OMAP_BCH
1881                 pr_info("nand: using OMAP_ECC_BCH8_CODE_HW ECC scheme\n");
1882                 nand_chip->ecc.mode             = NAND_ECC_HW;
1883                 nand_chip->ecc.size             = 512;
1884                 /* 14th bit is kept reserved for ROM-code compatibility */
1885                 nand_chip->ecc.bytes            = 13 + 1;
1886                 nand_chip->ecc.strength         = 8;
1887                 nand_chip->ecc.hwctl            = omap_enable_hwecc_bch;
1888                 nand_chip->ecc.correct          = omap_elm_correct_data;
1889                 nand_chip->ecc.calculate        = omap_calculate_ecc_bch;
1890                 nand_chip->ecc.read_page        = omap_read_page_bch;
1891                 nand_chip->ecc.write_page       = omap_write_page_bch;
1892                 /* This ECC scheme requires ELM H/W block */
1893                 err = is_elm_present(info, pdata->elm_of_node, BCH8_ECC);
1894                 if (err < 0) {
1895                         pr_err("nand: error: could not initialize ELM\n");
1896                         goto return_error;
1897                 }
1898                 /* define ECC layout */
1899                 ecclayout->eccbytes             = nand_chip->ecc.bytes *
1900                                                         (mtd->writesize /
1901                                                         nand_chip->ecc.size);
1902                 oob_index                       = BADBLOCK_MARKER_LENGTH;
1903                 for (i = 0; i < ecclayout->eccbytes; i++, oob_index++)
1904                         ecclayout->eccpos[i]    = oob_index;
1905                 /* reserved marker already included in ecclayout->eccbytes */
1906                 ecclayout->oobfree->offset      =
1907                                 ecclayout->eccpos[ecclayout->eccbytes - 1] + 1;
1908                 break;
1909 #else
1910                 pr_err("nand: error: CONFIG_MTD_NAND_OMAP_BCH not enabled\n");
1911                 err = -EINVAL;
1912                 goto return_error;
1913 #endif
1914 
1915         default:
1916                 pr_err("nand: error: invalid or unsupported ECC scheme\n");
1917                 err = -EINVAL;
1918                 goto return_error;
1919         }
1920 
1921         /* all OOB bytes from oobfree->offset till end off OOB are free */
1922         ecclayout->oobfree->length = mtd->oobsize - ecclayout->oobfree->offset;
1923         /* check if NAND device's OOB is enough to store ECC signatures */
1924         if (mtd->oobsize < (ecclayout->eccbytes + BADBLOCK_MARKER_LENGTH)) {
1925                 pr_err("not enough OOB bytes required = %d, available=%d\n",
1926                                            ecclayout->eccbytes, mtd->oobsize);
1927                 err = -EINVAL;
1928                 goto return_error;
1929         }
1930 
1931         /* second phase scan */
1932         if (nand_scan_tail(mtd)) {
1933                 err = -ENXIO;
1934                 goto return_error;
1935         }
1936 
1937         ppdata.of_node = pdata->of_node;
1938         mtd_device_parse_register(mtd, NULL, &ppdata, pdata->parts,
1939                                   pdata->nr_parts);
1940 
1941         platform_set_drvdata(pdev, mtd);
1942 
1943         return 0;
1944 
1945 return_error:
1946         if (info->dma)
1947                 dma_release_channel(info->dma);
1948         if (nand_chip->ecc.priv) {
1949                 nand_bch_free(nand_chip->ecc.priv);
1950                 nand_chip->ecc.priv = NULL;
1951         }
1952         return err;
1953 }
1954 
1955 static int omap_nand_remove(struct platform_device *pdev)
1956 {
1957         struct mtd_info *mtd = platform_get_drvdata(pdev);
1958         struct nand_chip *nand_chip = mtd->priv;
1959         struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
1960                                                         mtd);
1961         if (nand_chip->ecc.priv) {
1962                 nand_bch_free(nand_chip->ecc.priv);
1963                 nand_chip->ecc.priv = NULL;
1964         }
1965         if (info->dma)
1966                 dma_release_channel(info->dma);
1967         nand_release(mtd);
1968         return 0;
1969 }
1970 
1971 static struct platform_driver omap_nand_driver = {
1972         .probe          = omap_nand_probe,
1973         .remove         = omap_nand_remove,
1974         .driver         = {
1975                 .name   = DRIVER_NAME,
1976                 .owner  = THIS_MODULE,
1977         },
1978 };
1979 
1980 module_platform_driver(omap_nand_driver);
1981 
1982 MODULE_ALIAS("platform:" DRIVER_NAME);
1983 MODULE_LICENSE("GPL");
1984 MODULE_DESCRIPTION("Glue layer for NAND flash on TI OMAP boards");
1985 

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