Version:  2.0.40 2.2.26 2.4.37 3.11 3.12 3.13 3.14 3.15 3.16 3.17 3.18 3.19 4.0 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8

Linux/drivers/mtd/nand/gpmi-nand/gpmi-nand.c

  1 /*
  2  * Freescale GPMI NAND Flash Driver
  3  *
  4  * Copyright (C) 2010-2015 Freescale Semiconductor, Inc.
  5  * Copyright (C) 2008 Embedded Alley Solutions, Inc.
  6  *
  7  * This program is free software; you can redistribute it and/or modify
  8  * it under the terms of the GNU General Public License as published by
  9  * the Free Software Foundation; either version 2 of the License, or
 10  * (at your option) any later version.
 11  *
 12  * This program is distributed in the hope that it will be useful,
 13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
 14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 15  * GNU General Public License for more details.
 16  *
 17  * You should have received a copy of the GNU General Public License along
 18  * with this program; if not, write to the Free Software Foundation, Inc.,
 19  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 20  */
 21 #include <linux/clk.h>
 22 #include <linux/slab.h>
 23 #include <linux/interrupt.h>
 24 #include <linux/module.h>
 25 #include <linux/mtd/partitions.h>
 26 #include <linux/of.h>
 27 #include <linux/of_device.h>
 28 #include "gpmi-nand.h"
 29 #include "bch-regs.h"
 30 
 31 /* Resource names for the GPMI NAND driver. */
 32 #define GPMI_NAND_GPMI_REGS_ADDR_RES_NAME  "gpmi-nand"
 33 #define GPMI_NAND_BCH_REGS_ADDR_RES_NAME   "bch"
 34 #define GPMI_NAND_BCH_INTERRUPT_RES_NAME   "bch"
 35 
 36 /* add our owner bbt descriptor */
 37 static uint8_t scan_ff_pattern[] = { 0xff };
 38 static struct nand_bbt_descr gpmi_bbt_descr = {
 39         .options        = 0,
 40         .offs           = 0,
 41         .len            = 1,
 42         .pattern        = scan_ff_pattern
 43 };
 44 
 45 /*
 46  * We may change the layout if we can get the ECC info from the datasheet,
 47  * else we will use all the (page + OOB).
 48  */
 49 static int gpmi_ooblayout_ecc(struct mtd_info *mtd, int section,
 50                               struct mtd_oob_region *oobregion)
 51 {
 52         struct nand_chip *chip = mtd_to_nand(mtd);
 53         struct gpmi_nand_data *this = nand_get_controller_data(chip);
 54         struct bch_geometry *geo = &this->bch_geometry;
 55 
 56         if (section)
 57                 return -ERANGE;
 58 
 59         oobregion->offset = 0;
 60         oobregion->length = geo->page_size - mtd->writesize;
 61 
 62         return 0;
 63 }
 64 
 65 static int gpmi_ooblayout_free(struct mtd_info *mtd, int section,
 66                                struct mtd_oob_region *oobregion)
 67 {
 68         struct nand_chip *chip = mtd_to_nand(mtd);
 69         struct gpmi_nand_data *this = nand_get_controller_data(chip);
 70         struct bch_geometry *geo = &this->bch_geometry;
 71 
 72         if (section)
 73                 return -ERANGE;
 74 
 75         /* The available oob size we have. */
 76         if (geo->page_size < mtd->writesize + mtd->oobsize) {
 77                 oobregion->offset = geo->page_size - mtd->writesize;
 78                 oobregion->length = mtd->oobsize - oobregion->offset;
 79         }
 80 
 81         return 0;
 82 }
 83 
 84 static const struct mtd_ooblayout_ops gpmi_ooblayout_ops = {
 85         .ecc = gpmi_ooblayout_ecc,
 86         .free = gpmi_ooblayout_free,
 87 };
 88 
 89 static const struct gpmi_devdata gpmi_devdata_imx23 = {
 90         .type = IS_MX23,
 91         .bch_max_ecc_strength = 20,
 92         .max_chain_delay = 16,
 93 };
 94 
 95 static const struct gpmi_devdata gpmi_devdata_imx28 = {
 96         .type = IS_MX28,
 97         .bch_max_ecc_strength = 20,
 98         .max_chain_delay = 16,
 99 };
100 
101 static const struct gpmi_devdata gpmi_devdata_imx6q = {
102         .type = IS_MX6Q,
103         .bch_max_ecc_strength = 40,
104         .max_chain_delay = 12,
105 };
106 
107 static const struct gpmi_devdata gpmi_devdata_imx6sx = {
108         .type = IS_MX6SX,
109         .bch_max_ecc_strength = 62,
110         .max_chain_delay = 12,
111 };
112 
113 static irqreturn_t bch_irq(int irq, void *cookie)
114 {
115         struct gpmi_nand_data *this = cookie;
116 
117         gpmi_clear_bch(this);
118         complete(&this->bch_done);
119         return IRQ_HANDLED;
120 }
121 
122 /*
123  *  Calculate the ECC strength by hand:
124  *      E : The ECC strength.
125  *      G : the length of Galois Field.
126  *      N : The chunk count of per page.
127  *      O : the oobsize of the NAND chip.
128  *      M : the metasize of per page.
129  *
130  *      The formula is :
131  *              E * G * N
132  *            ------------ <= (O - M)
133  *                  8
134  *
135  *      So, we get E by:
136  *                    (O - M) * 8
137  *              E <= -------------
138  *                       G * N
139  */
140 static inline int get_ecc_strength(struct gpmi_nand_data *this)
141 {
142         struct bch_geometry *geo = &this->bch_geometry;
143         struct mtd_info *mtd = nand_to_mtd(&this->nand);
144         int ecc_strength;
145 
146         ecc_strength = ((mtd->oobsize - geo->metadata_size) * 8)
147                         / (geo->gf_len * geo->ecc_chunk_count);
148 
149         /* We need the minor even number. */
150         return round_down(ecc_strength, 2);
151 }
152 
153 static inline bool gpmi_check_ecc(struct gpmi_nand_data *this)
154 {
155         struct bch_geometry *geo = &this->bch_geometry;
156 
157         /* Do the sanity check. */
158         if (GPMI_IS_MX23(this) || GPMI_IS_MX28(this)) {
159                 /* The mx23/mx28 only support the GF13. */
160                 if (geo->gf_len == 14)
161                         return false;
162         }
163         return geo->ecc_strength <= this->devdata->bch_max_ecc_strength;
164 }
165 
166 /*
167  * If we can get the ECC information from the nand chip, we do not
168  * need to calculate them ourselves.
169  *
170  * We may have available oob space in this case.
171  */
172 static int set_geometry_by_ecc_info(struct gpmi_nand_data *this)
173 {
174         struct bch_geometry *geo = &this->bch_geometry;
175         struct nand_chip *chip = &this->nand;
176         struct mtd_info *mtd = nand_to_mtd(chip);
177         unsigned int block_mark_bit_offset;
178 
179         if (!(chip->ecc_strength_ds > 0 && chip->ecc_step_ds > 0))
180                 return -EINVAL;
181 
182         switch (chip->ecc_step_ds) {
183         case SZ_512:
184                 geo->gf_len = 13;
185                 break;
186         case SZ_1K:
187                 geo->gf_len = 14;
188                 break;
189         default:
190                 dev_err(this->dev,
191                         "unsupported nand chip. ecc bits : %d, ecc size : %d\n",
192                         chip->ecc_strength_ds, chip->ecc_step_ds);
193                 return -EINVAL;
194         }
195         geo->ecc_chunk_size = chip->ecc_step_ds;
196         geo->ecc_strength = round_up(chip->ecc_strength_ds, 2);
197         if (!gpmi_check_ecc(this))
198                 return -EINVAL;
199 
200         /* Keep the C >= O */
201         if (geo->ecc_chunk_size < mtd->oobsize) {
202                 dev_err(this->dev,
203                         "unsupported nand chip. ecc size: %d, oob size : %d\n",
204                         chip->ecc_step_ds, mtd->oobsize);
205                 return -EINVAL;
206         }
207 
208         /* The default value, see comment in the legacy_set_geometry(). */
209         geo->metadata_size = 10;
210 
211         geo->ecc_chunk_count = mtd->writesize / geo->ecc_chunk_size;
212 
213         /*
214          * Now, the NAND chip with 2K page(data chunk is 512byte) shows below:
215          *
216          *    |                          P                            |
217          *    |<----------------------------------------------------->|
218          *    |                                                       |
219          *    |                                        (Block Mark)   |
220          *    |                      P'                      |      | |     |
221          *    |<-------------------------------------------->|  D   | |  O' |
222          *    |                                              |<---->| |<--->|
223          *    V                                              V      V V     V
224          *    +---+----------+-+----------+-+----------+-+----------+-+-----+
225          *    | M |   data   |E|   data   |E|   data   |E|   data   |E|     |
226          *    +---+----------+-+----------+-+----------+-+----------+-+-----+
227          *                                                   ^              ^
228          *                                                   |      O       |
229          *                                                   |<------------>|
230          *                                                   |              |
231          *
232          *      P : the page size for BCH module.
233          *      E : The ECC strength.
234          *      G : the length of Galois Field.
235          *      N : The chunk count of per page.
236          *      M : the metasize of per page.
237          *      C : the ecc chunk size, aka the "data" above.
238          *      P': the nand chip's page size.
239          *      O : the nand chip's oob size.
240          *      O': the free oob.
241          *
242          *      The formula for P is :
243          *
244          *                  E * G * N
245          *             P = ------------ + P' + M
246          *                      8
247          *
248          * The position of block mark moves forward in the ECC-based view
249          * of page, and the delta is:
250          *
251          *                   E * G * (N - 1)
252          *             D = (---------------- + M)
253          *                          8
254          *
255          * Please see the comment in legacy_set_geometry().
256          * With the condition C >= O , we still can get same result.
257          * So the bit position of the physical block mark within the ECC-based
258          * view of the page is :
259          *             (P' - D) * 8
260          */
261         geo->page_size = mtd->writesize + geo->metadata_size +
262                 (geo->gf_len * geo->ecc_strength * geo->ecc_chunk_count) / 8;
263 
264         geo->payload_size = mtd->writesize;
265 
266         geo->auxiliary_status_offset = ALIGN(geo->metadata_size, 4);
267         geo->auxiliary_size = ALIGN(geo->metadata_size, 4)
268                                 + ALIGN(geo->ecc_chunk_count, 4);
269 
270         if (!this->swap_block_mark)
271                 return 0;
272 
273         /* For bit swap. */
274         block_mark_bit_offset = mtd->writesize * 8 -
275                 (geo->ecc_strength * geo->gf_len * (geo->ecc_chunk_count - 1)
276                                 + geo->metadata_size * 8);
277 
278         geo->block_mark_byte_offset = block_mark_bit_offset / 8;
279         geo->block_mark_bit_offset  = block_mark_bit_offset % 8;
280         return 0;
281 }
282 
283 static int legacy_set_geometry(struct gpmi_nand_data *this)
284 {
285         struct bch_geometry *geo = &this->bch_geometry;
286         struct mtd_info *mtd = nand_to_mtd(&this->nand);
287         unsigned int metadata_size;
288         unsigned int status_size;
289         unsigned int block_mark_bit_offset;
290 
291         /*
292          * The size of the metadata can be changed, though we set it to 10
293          * bytes now. But it can't be too large, because we have to save
294          * enough space for BCH.
295          */
296         geo->metadata_size = 10;
297 
298         /* The default for the length of Galois Field. */
299         geo->gf_len = 13;
300 
301         /* The default for chunk size. */
302         geo->ecc_chunk_size = 512;
303         while (geo->ecc_chunk_size < mtd->oobsize) {
304                 geo->ecc_chunk_size *= 2; /* keep C >= O */
305                 geo->gf_len = 14;
306         }
307 
308         geo->ecc_chunk_count = mtd->writesize / geo->ecc_chunk_size;
309 
310         /* We use the same ECC strength for all chunks. */
311         geo->ecc_strength = get_ecc_strength(this);
312         if (!gpmi_check_ecc(this)) {
313                 dev_err(this->dev,
314                         "ecc strength: %d cannot be supported by the controller (%d)\n"
315                         "try to use minimum ecc strength that NAND chip required\n",
316                         geo->ecc_strength,
317                         this->devdata->bch_max_ecc_strength);
318                 return -EINVAL;
319         }
320 
321         geo->page_size = mtd->writesize + mtd->oobsize;
322         geo->payload_size = mtd->writesize;
323 
324         /*
325          * The auxiliary buffer contains the metadata and the ECC status. The
326          * metadata is padded to the nearest 32-bit boundary. The ECC status
327          * contains one byte for every ECC chunk, and is also padded to the
328          * nearest 32-bit boundary.
329          */
330         metadata_size = ALIGN(geo->metadata_size, 4);
331         status_size   = ALIGN(geo->ecc_chunk_count, 4);
332 
333         geo->auxiliary_size = metadata_size + status_size;
334         geo->auxiliary_status_offset = metadata_size;
335 
336         if (!this->swap_block_mark)
337                 return 0;
338 
339         /*
340          * We need to compute the byte and bit offsets of
341          * the physical block mark within the ECC-based view of the page.
342          *
343          * NAND chip with 2K page shows below:
344          *                                             (Block Mark)
345          *                                                   |      |
346          *                                                   |  D   |
347          *                                                   |<---->|
348          *                                                   V      V
349          *    +---+----------+-+----------+-+----------+-+----------+-+
350          *    | M |   data   |E|   data   |E|   data   |E|   data   |E|
351          *    +---+----------+-+----------+-+----------+-+----------+-+
352          *
353          * The position of block mark moves forward in the ECC-based view
354          * of page, and the delta is:
355          *
356          *                   E * G * (N - 1)
357          *             D = (---------------- + M)
358          *                          8
359          *
360          * With the formula to compute the ECC strength, and the condition
361          *       : C >= O         (C is the ecc chunk size)
362          *
363          * It's easy to deduce to the following result:
364          *
365          *         E * G       (O - M)      C - M         C - M
366          *      ----------- <= ------- <=  --------  <  ---------
367          *           8            N           N          (N - 1)
368          *
369          *  So, we get:
370          *
371          *                   E * G * (N - 1)
372          *             D = (---------------- + M) < C
373          *                          8
374          *
375          *  The above inequality means the position of block mark
376          *  within the ECC-based view of the page is still in the data chunk,
377          *  and it's NOT in the ECC bits of the chunk.
378          *
379          *  Use the following to compute the bit position of the
380          *  physical block mark within the ECC-based view of the page:
381          *          (page_size - D) * 8
382          *
383          *  --Huang Shijie
384          */
385         block_mark_bit_offset = mtd->writesize * 8 -
386                 (geo->ecc_strength * geo->gf_len * (geo->ecc_chunk_count - 1)
387                                 + geo->metadata_size * 8);
388 
389         geo->block_mark_byte_offset = block_mark_bit_offset / 8;
390         geo->block_mark_bit_offset  = block_mark_bit_offset % 8;
391         return 0;
392 }
393 
394 int common_nfc_set_geometry(struct gpmi_nand_data *this)
395 {
396         if ((of_property_read_bool(this->dev->of_node, "fsl,use-minimum-ecc"))
397                                 || legacy_set_geometry(this))
398                 return set_geometry_by_ecc_info(this);
399 
400         return 0;
401 }
402 
403 struct dma_chan *get_dma_chan(struct gpmi_nand_data *this)
404 {
405         /* We use the DMA channel 0 to access all the nand chips. */
406         return this->dma_chans[0];
407 }
408 
409 /* Can we use the upper's buffer directly for DMA? */
410 void prepare_data_dma(struct gpmi_nand_data *this, enum dma_data_direction dr)
411 {
412         struct scatterlist *sgl = &this->data_sgl;
413         int ret;
414 
415         /* first try to map the upper buffer directly */
416         if (virt_addr_valid(this->upper_buf) &&
417                 !object_is_on_stack(this->upper_buf)) {
418                 sg_init_one(sgl, this->upper_buf, this->upper_len);
419                 ret = dma_map_sg(this->dev, sgl, 1, dr);
420                 if (ret == 0)
421                         goto map_fail;
422 
423                 this->direct_dma_map_ok = true;
424                 return;
425         }
426 
427 map_fail:
428         /* We have to use our own DMA buffer. */
429         sg_init_one(sgl, this->data_buffer_dma, this->upper_len);
430 
431         if (dr == DMA_TO_DEVICE)
432                 memcpy(this->data_buffer_dma, this->upper_buf, this->upper_len);
433 
434         dma_map_sg(this->dev, sgl, 1, dr);
435 
436         this->direct_dma_map_ok = false;
437 }
438 
439 /* This will be called after the DMA operation is finished. */
440 static void dma_irq_callback(void *param)
441 {
442         struct gpmi_nand_data *this = param;
443         struct completion *dma_c = &this->dma_done;
444 
445         switch (this->dma_type) {
446         case DMA_FOR_COMMAND:
447                 dma_unmap_sg(this->dev, &this->cmd_sgl, 1, DMA_TO_DEVICE);
448                 break;
449 
450         case DMA_FOR_READ_DATA:
451                 dma_unmap_sg(this->dev, &this->data_sgl, 1, DMA_FROM_DEVICE);
452                 if (this->direct_dma_map_ok == false)
453                         memcpy(this->upper_buf, this->data_buffer_dma,
454                                 this->upper_len);
455                 break;
456 
457         case DMA_FOR_WRITE_DATA:
458                 dma_unmap_sg(this->dev, &this->data_sgl, 1, DMA_TO_DEVICE);
459                 break;
460 
461         case DMA_FOR_READ_ECC_PAGE:
462         case DMA_FOR_WRITE_ECC_PAGE:
463                 /* We have to wait the BCH interrupt to finish. */
464                 break;
465 
466         default:
467                 dev_err(this->dev, "in wrong DMA operation.\n");
468         }
469 
470         complete(dma_c);
471 }
472 
473 int start_dma_without_bch_irq(struct gpmi_nand_data *this,
474                                 struct dma_async_tx_descriptor *desc)
475 {
476         struct completion *dma_c = &this->dma_done;
477         unsigned long timeout;
478 
479         init_completion(dma_c);
480 
481         desc->callback          = dma_irq_callback;
482         desc->callback_param    = this;
483         dmaengine_submit(desc);
484         dma_async_issue_pending(get_dma_chan(this));
485 
486         /* Wait for the interrupt from the DMA block. */
487         timeout = wait_for_completion_timeout(dma_c, msecs_to_jiffies(1000));
488         if (!timeout) {
489                 dev_err(this->dev, "DMA timeout, last DMA :%d\n",
490                         this->last_dma_type);
491                 gpmi_dump_info(this);
492                 return -ETIMEDOUT;
493         }
494         return 0;
495 }
496 
497 /*
498  * This function is used in BCH reading or BCH writing pages.
499  * It will wait for the BCH interrupt as long as ONE second.
500  * Actually, we must wait for two interrupts :
501  *      [1] firstly the DMA interrupt and
502  *      [2] secondly the BCH interrupt.
503  */
504 int start_dma_with_bch_irq(struct gpmi_nand_data *this,
505                         struct dma_async_tx_descriptor *desc)
506 {
507         struct completion *bch_c = &this->bch_done;
508         unsigned long timeout;
509 
510         /* Prepare to receive an interrupt from the BCH block. */
511         init_completion(bch_c);
512 
513         /* start the DMA */
514         start_dma_without_bch_irq(this, desc);
515 
516         /* Wait for the interrupt from the BCH block. */
517         timeout = wait_for_completion_timeout(bch_c, msecs_to_jiffies(1000));
518         if (!timeout) {
519                 dev_err(this->dev, "BCH timeout, last DMA :%d\n",
520                         this->last_dma_type);
521                 gpmi_dump_info(this);
522                 return -ETIMEDOUT;
523         }
524         return 0;
525 }
526 
527 static int acquire_register_block(struct gpmi_nand_data *this,
528                                   const char *res_name)
529 {
530         struct platform_device *pdev = this->pdev;
531         struct resources *res = &this->resources;
532         struct resource *r;
533         void __iomem *p;
534 
535         r = platform_get_resource_byname(pdev, IORESOURCE_MEM, res_name);
536         p = devm_ioremap_resource(&pdev->dev, r);
537         if (IS_ERR(p))
538                 return PTR_ERR(p);
539 
540         if (!strcmp(res_name, GPMI_NAND_GPMI_REGS_ADDR_RES_NAME))
541                 res->gpmi_regs = p;
542         else if (!strcmp(res_name, GPMI_NAND_BCH_REGS_ADDR_RES_NAME))
543                 res->bch_regs = p;
544         else
545                 dev_err(this->dev, "unknown resource name : %s\n", res_name);
546 
547         return 0;
548 }
549 
550 static int acquire_bch_irq(struct gpmi_nand_data *this, irq_handler_t irq_h)
551 {
552         struct platform_device *pdev = this->pdev;
553         const char *res_name = GPMI_NAND_BCH_INTERRUPT_RES_NAME;
554         struct resource *r;
555         int err;
556 
557         r = platform_get_resource_byname(pdev, IORESOURCE_IRQ, res_name);
558         if (!r) {
559                 dev_err(this->dev, "Can't get resource for %s\n", res_name);
560                 return -ENODEV;
561         }
562 
563         err = devm_request_irq(this->dev, r->start, irq_h, 0, res_name, this);
564         if (err)
565                 dev_err(this->dev, "error requesting BCH IRQ\n");
566 
567         return err;
568 }
569 
570 static void release_dma_channels(struct gpmi_nand_data *this)
571 {
572         unsigned int i;
573         for (i = 0; i < DMA_CHANS; i++)
574                 if (this->dma_chans[i]) {
575                         dma_release_channel(this->dma_chans[i]);
576                         this->dma_chans[i] = NULL;
577                 }
578 }
579 
580 static int acquire_dma_channels(struct gpmi_nand_data *this)
581 {
582         struct platform_device *pdev = this->pdev;
583         struct dma_chan *dma_chan;
584 
585         /* request dma channel */
586         dma_chan = dma_request_slave_channel(&pdev->dev, "rx-tx");
587         if (!dma_chan) {
588                 dev_err(this->dev, "Failed to request DMA channel.\n");
589                 goto acquire_err;
590         }
591 
592         this->dma_chans[0] = dma_chan;
593         return 0;
594 
595 acquire_err:
596         release_dma_channels(this);
597         return -EINVAL;
598 }
599 
600 static char *extra_clks_for_mx6q[GPMI_CLK_MAX] = {
601         "gpmi_apb", "gpmi_bch", "gpmi_bch_apb", "per1_bch",
602 };
603 
604 static int gpmi_get_clks(struct gpmi_nand_data *this)
605 {
606         struct resources *r = &this->resources;
607         char **extra_clks = NULL;
608         struct clk *clk;
609         int err, i;
610 
611         /* The main clock is stored in the first. */
612         r->clock[0] = devm_clk_get(this->dev, "gpmi_io");
613         if (IS_ERR(r->clock[0])) {
614                 err = PTR_ERR(r->clock[0]);
615                 goto err_clock;
616         }
617 
618         /* Get extra clocks */
619         if (GPMI_IS_MX6(this))
620                 extra_clks = extra_clks_for_mx6q;
621         if (!extra_clks)
622                 return 0;
623 
624         for (i = 1; i < GPMI_CLK_MAX; i++) {
625                 if (extra_clks[i - 1] == NULL)
626                         break;
627 
628                 clk = devm_clk_get(this->dev, extra_clks[i - 1]);
629                 if (IS_ERR(clk)) {
630                         err = PTR_ERR(clk);
631                         goto err_clock;
632                 }
633 
634                 r->clock[i] = clk;
635         }
636 
637         if (GPMI_IS_MX6(this))
638                 /*
639                  * Set the default value for the gpmi clock.
640                  *
641                  * If you want to use the ONFI nand which is in the
642                  * Synchronous Mode, you should change the clock as you need.
643                  */
644                 clk_set_rate(r->clock[0], 22000000);
645 
646         return 0;
647 
648 err_clock:
649         dev_dbg(this->dev, "failed in finding the clocks.\n");
650         return err;
651 }
652 
653 static int acquire_resources(struct gpmi_nand_data *this)
654 {
655         int ret;
656 
657         ret = acquire_register_block(this, GPMI_NAND_GPMI_REGS_ADDR_RES_NAME);
658         if (ret)
659                 goto exit_regs;
660 
661         ret = acquire_register_block(this, GPMI_NAND_BCH_REGS_ADDR_RES_NAME);
662         if (ret)
663                 goto exit_regs;
664 
665         ret = acquire_bch_irq(this, bch_irq);
666         if (ret)
667                 goto exit_regs;
668 
669         ret = acquire_dma_channels(this);
670         if (ret)
671                 goto exit_regs;
672 
673         ret = gpmi_get_clks(this);
674         if (ret)
675                 goto exit_clock;
676         return 0;
677 
678 exit_clock:
679         release_dma_channels(this);
680 exit_regs:
681         return ret;
682 }
683 
684 static void release_resources(struct gpmi_nand_data *this)
685 {
686         release_dma_channels(this);
687 }
688 
689 static int init_hardware(struct gpmi_nand_data *this)
690 {
691         int ret;
692 
693         /*
694          * This structure contains the "safe" GPMI timing that should succeed
695          * with any NAND Flash device
696          * (although, with less-than-optimal performance).
697          */
698         struct nand_timing  safe_timing = {
699                 .data_setup_in_ns        = 80,
700                 .data_hold_in_ns         = 60,
701                 .address_setup_in_ns     = 25,
702                 .gpmi_sample_delay_in_ns =  6,
703                 .tREA_in_ns              = -1,
704                 .tRLOH_in_ns             = -1,
705                 .tRHOH_in_ns             = -1,
706         };
707 
708         /* Initialize the hardwares. */
709         ret = gpmi_init(this);
710         if (ret)
711                 return ret;
712 
713         this->timing = safe_timing;
714         return 0;
715 }
716 
717 static int read_page_prepare(struct gpmi_nand_data *this,
718                         void *destination, unsigned length,
719                         void *alt_virt, dma_addr_t alt_phys, unsigned alt_size,
720                         void **use_virt, dma_addr_t *use_phys)
721 {
722         struct device *dev = this->dev;
723 
724         if (virt_addr_valid(destination)) {
725                 dma_addr_t dest_phys;
726 
727                 dest_phys = dma_map_single(dev, destination,
728                                                 length, DMA_FROM_DEVICE);
729                 if (dma_mapping_error(dev, dest_phys)) {
730                         if (alt_size < length) {
731                                 dev_err(dev, "Alternate buffer is too small\n");
732                                 return -ENOMEM;
733                         }
734                         goto map_failed;
735                 }
736                 *use_virt = destination;
737                 *use_phys = dest_phys;
738                 this->direct_dma_map_ok = true;
739                 return 0;
740         }
741 
742 map_failed:
743         *use_virt = alt_virt;
744         *use_phys = alt_phys;
745         this->direct_dma_map_ok = false;
746         return 0;
747 }
748 
749 static inline void read_page_end(struct gpmi_nand_data *this,
750                         void *destination, unsigned length,
751                         void *alt_virt, dma_addr_t alt_phys, unsigned alt_size,
752                         void *used_virt, dma_addr_t used_phys)
753 {
754         if (this->direct_dma_map_ok)
755                 dma_unmap_single(this->dev, used_phys, length, DMA_FROM_DEVICE);
756 }
757 
758 static inline void read_page_swap_end(struct gpmi_nand_data *this,
759                         void *destination, unsigned length,
760                         void *alt_virt, dma_addr_t alt_phys, unsigned alt_size,
761                         void *used_virt, dma_addr_t used_phys)
762 {
763         if (!this->direct_dma_map_ok)
764                 memcpy(destination, alt_virt, length);
765 }
766 
767 static int send_page_prepare(struct gpmi_nand_data *this,
768                         const void *source, unsigned length,
769                         void *alt_virt, dma_addr_t alt_phys, unsigned alt_size,
770                         const void **use_virt, dma_addr_t *use_phys)
771 {
772         struct device *dev = this->dev;
773 
774         if (virt_addr_valid(source)) {
775                 dma_addr_t source_phys;
776 
777                 source_phys = dma_map_single(dev, (void *)source, length,
778                                                 DMA_TO_DEVICE);
779                 if (dma_mapping_error(dev, source_phys)) {
780                         if (alt_size < length) {
781                                 dev_err(dev, "Alternate buffer is too small\n");
782                                 return -ENOMEM;
783                         }
784                         goto map_failed;
785                 }
786                 *use_virt = source;
787                 *use_phys = source_phys;
788                 return 0;
789         }
790 map_failed:
791         /*
792          * Copy the content of the source buffer into the alternate
793          * buffer and set up the return values accordingly.
794          */
795         memcpy(alt_virt, source, length);
796 
797         *use_virt = alt_virt;
798         *use_phys = alt_phys;
799         return 0;
800 }
801 
802 static void send_page_end(struct gpmi_nand_data *this,
803                         const void *source, unsigned length,
804                         void *alt_virt, dma_addr_t alt_phys, unsigned alt_size,
805                         const void *used_virt, dma_addr_t used_phys)
806 {
807         struct device *dev = this->dev;
808         if (used_virt == source)
809                 dma_unmap_single(dev, used_phys, length, DMA_TO_DEVICE);
810 }
811 
812 static void gpmi_free_dma_buffer(struct gpmi_nand_data *this)
813 {
814         struct device *dev = this->dev;
815 
816         if (this->page_buffer_virt && virt_addr_valid(this->page_buffer_virt))
817                 dma_free_coherent(dev, this->page_buffer_size,
818                                         this->page_buffer_virt,
819                                         this->page_buffer_phys);
820         kfree(this->cmd_buffer);
821         kfree(this->data_buffer_dma);
822         kfree(this->raw_buffer);
823 
824         this->cmd_buffer        = NULL;
825         this->data_buffer_dma   = NULL;
826         this->raw_buffer        = NULL;
827         this->page_buffer_virt  = NULL;
828         this->page_buffer_size  =  0;
829 }
830 
831 /* Allocate the DMA buffers */
832 static int gpmi_alloc_dma_buffer(struct gpmi_nand_data *this)
833 {
834         struct bch_geometry *geo = &this->bch_geometry;
835         struct device *dev = this->dev;
836         struct mtd_info *mtd = nand_to_mtd(&this->nand);
837 
838         /* [1] Allocate a command buffer. PAGE_SIZE is enough. */
839         this->cmd_buffer = kzalloc(PAGE_SIZE, GFP_DMA | GFP_KERNEL);
840         if (this->cmd_buffer == NULL)
841                 goto error_alloc;
842 
843         /*
844          * [2] Allocate a read/write data buffer.
845          *     The gpmi_alloc_dma_buffer can be called twice.
846          *     We allocate a PAGE_SIZE length buffer if gpmi_alloc_dma_buffer
847          *     is called before the nand_scan_ident; and we allocate a buffer
848          *     of the real NAND page size when the gpmi_alloc_dma_buffer is
849          *     called after the nand_scan_ident.
850          */
851         this->data_buffer_dma = kzalloc(mtd->writesize ?: PAGE_SIZE,
852                                         GFP_DMA | GFP_KERNEL);
853         if (this->data_buffer_dma == NULL)
854                 goto error_alloc;
855 
856         /*
857          * [3] Allocate the page buffer.
858          *
859          * Both the payload buffer and the auxiliary buffer must appear on
860          * 32-bit boundaries. We presume the size of the payload buffer is a
861          * power of two and is much larger than four, which guarantees the
862          * auxiliary buffer will appear on a 32-bit boundary.
863          */
864         this->page_buffer_size = geo->payload_size + geo->auxiliary_size;
865         this->page_buffer_virt = dma_alloc_coherent(dev, this->page_buffer_size,
866                                         &this->page_buffer_phys, GFP_DMA);
867         if (!this->page_buffer_virt)
868                 goto error_alloc;
869 
870         this->raw_buffer = kzalloc(mtd->writesize + mtd->oobsize, GFP_KERNEL);
871         if (!this->raw_buffer)
872                 goto error_alloc;
873 
874         /* Slice up the page buffer. */
875         this->payload_virt = this->page_buffer_virt;
876         this->payload_phys = this->page_buffer_phys;
877         this->auxiliary_virt = this->payload_virt + geo->payload_size;
878         this->auxiliary_phys = this->payload_phys + geo->payload_size;
879         return 0;
880 
881 error_alloc:
882         gpmi_free_dma_buffer(this);
883         return -ENOMEM;
884 }
885 
886 static void gpmi_cmd_ctrl(struct mtd_info *mtd, int data, unsigned int ctrl)
887 {
888         struct nand_chip *chip = mtd_to_nand(mtd);
889         struct gpmi_nand_data *this = nand_get_controller_data(chip);
890         int ret;
891 
892         /*
893          * Every operation begins with a command byte and a series of zero or
894          * more address bytes. These are distinguished by either the Address
895          * Latch Enable (ALE) or Command Latch Enable (CLE) signals being
896          * asserted. When MTD is ready to execute the command, it will deassert
897          * both latch enables.
898          *
899          * Rather than run a separate DMA operation for every single byte, we
900          * queue them up and run a single DMA operation for the entire series
901          * of command and data bytes. NAND_CMD_NONE means the END of the queue.
902          */
903         if ((ctrl & (NAND_ALE | NAND_CLE))) {
904                 if (data != NAND_CMD_NONE)
905                         this->cmd_buffer[this->command_length++] = data;
906                 return;
907         }
908 
909         if (!this->command_length)
910                 return;
911 
912         ret = gpmi_send_command(this);
913         if (ret)
914                 dev_err(this->dev, "Chip: %u, Error %d\n",
915                         this->current_chip, ret);
916 
917         this->command_length = 0;
918 }
919 
920 static int gpmi_dev_ready(struct mtd_info *mtd)
921 {
922         struct nand_chip *chip = mtd_to_nand(mtd);
923         struct gpmi_nand_data *this = nand_get_controller_data(chip);
924 
925         return gpmi_is_ready(this, this->current_chip);
926 }
927 
928 static void gpmi_select_chip(struct mtd_info *mtd, int chipnr)
929 {
930         struct nand_chip *chip = mtd_to_nand(mtd);
931         struct gpmi_nand_data *this = nand_get_controller_data(chip);
932 
933         if ((this->current_chip < 0) && (chipnr >= 0))
934                 gpmi_begin(this);
935         else if ((this->current_chip >= 0) && (chipnr < 0))
936                 gpmi_end(this);
937 
938         this->current_chip = chipnr;
939 }
940 
941 static void gpmi_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
942 {
943         struct nand_chip *chip = mtd_to_nand(mtd);
944         struct gpmi_nand_data *this = nand_get_controller_data(chip);
945 
946         dev_dbg(this->dev, "len is %d\n", len);
947         this->upper_buf = buf;
948         this->upper_len = len;
949 
950         gpmi_read_data(this);
951 }
952 
953 static void gpmi_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
954 {
955         struct nand_chip *chip = mtd_to_nand(mtd);
956         struct gpmi_nand_data *this = nand_get_controller_data(chip);
957 
958         dev_dbg(this->dev, "len is %d\n", len);
959         this->upper_buf = (uint8_t *)buf;
960         this->upper_len = len;
961 
962         gpmi_send_data(this);
963 }
964 
965 static uint8_t gpmi_read_byte(struct mtd_info *mtd)
966 {
967         struct nand_chip *chip = mtd_to_nand(mtd);
968         struct gpmi_nand_data *this = nand_get_controller_data(chip);
969         uint8_t *buf = this->data_buffer_dma;
970 
971         gpmi_read_buf(mtd, buf, 1);
972         return buf[0];
973 }
974 
975 /*
976  * Handles block mark swapping.
977  * It can be called in swapping the block mark, or swapping it back,
978  * because the the operations are the same.
979  */
980 static void block_mark_swapping(struct gpmi_nand_data *this,
981                                 void *payload, void *auxiliary)
982 {
983         struct bch_geometry *nfc_geo = &this->bch_geometry;
984         unsigned char *p;
985         unsigned char *a;
986         unsigned int  bit;
987         unsigned char mask;
988         unsigned char from_data;
989         unsigned char from_oob;
990 
991         if (!this->swap_block_mark)
992                 return;
993 
994         /*
995          * If control arrives here, we're swapping. Make some convenience
996          * variables.
997          */
998         bit = nfc_geo->block_mark_bit_offset;
999         p   = payload + nfc_geo->block_mark_byte_offset;
1000         a   = auxiliary;
1001 
1002         /*
1003          * Get the byte from the data area that overlays the block mark. Since
1004          * the ECC engine applies its own view to the bits in the page, the
1005          * physical block mark won't (in general) appear on a byte boundary in
1006          * the data.
1007          */
1008         from_data = (p[0] >> bit) | (p[1] << (8 - bit));
1009 
1010         /* Get the byte from the OOB. */
1011         from_oob = a[0];
1012 
1013         /* Swap them. */
1014         a[0] = from_data;
1015 
1016         mask = (0x1 << bit) - 1;
1017         p[0] = (p[0] & mask) | (from_oob << bit);
1018 
1019         mask = ~0 << bit;
1020         p[1] = (p[1] & mask) | (from_oob >> (8 - bit));
1021 }
1022 
1023 static int gpmi_ecc_read_page(struct mtd_info *mtd, struct nand_chip *chip,
1024                                 uint8_t *buf, int oob_required, int page)
1025 {
1026         struct gpmi_nand_data *this = nand_get_controller_data(chip);
1027         struct bch_geometry *nfc_geo = &this->bch_geometry;
1028         void          *payload_virt;
1029         dma_addr_t    payload_phys;
1030         void          *auxiliary_virt;
1031         dma_addr_t    auxiliary_phys;
1032         unsigned int  i;
1033         unsigned char *status;
1034         unsigned int  max_bitflips = 0;
1035         int           ret;
1036 
1037         dev_dbg(this->dev, "page number is : %d\n", page);
1038         ret = read_page_prepare(this, buf, nfc_geo->payload_size,
1039                                         this->payload_virt, this->payload_phys,
1040                                         nfc_geo->payload_size,
1041                                         &payload_virt, &payload_phys);
1042         if (ret) {
1043                 dev_err(this->dev, "Inadequate DMA buffer\n");
1044                 ret = -ENOMEM;
1045                 return ret;
1046         }
1047         auxiliary_virt = this->auxiliary_virt;
1048         auxiliary_phys = this->auxiliary_phys;
1049 
1050         /* go! */
1051         ret = gpmi_read_page(this, payload_phys, auxiliary_phys);
1052         read_page_end(this, buf, nfc_geo->payload_size,
1053                         this->payload_virt, this->payload_phys,
1054                         nfc_geo->payload_size,
1055                         payload_virt, payload_phys);
1056         if (ret) {
1057                 dev_err(this->dev, "Error in ECC-based read: %d\n", ret);
1058                 return ret;
1059         }
1060 
1061         /* handle the block mark swapping */
1062         block_mark_swapping(this, payload_virt, auxiliary_virt);
1063 
1064         /* Loop over status bytes, accumulating ECC status. */
1065         status = auxiliary_virt + nfc_geo->auxiliary_status_offset;
1066 
1067         read_page_swap_end(this, buf, nfc_geo->payload_size,
1068                            this->payload_virt, this->payload_phys,
1069                            nfc_geo->payload_size,
1070                            payload_virt, payload_phys);
1071 
1072         for (i = 0; i < nfc_geo->ecc_chunk_count; i++, status++) {
1073                 if ((*status == STATUS_GOOD) || (*status == STATUS_ERASED))
1074                         continue;
1075 
1076                 if (*status == STATUS_UNCORRECTABLE) {
1077                         int eccbits = nfc_geo->ecc_strength * nfc_geo->gf_len;
1078                         u8 *eccbuf = this->raw_buffer;
1079                         int offset, bitoffset;
1080                         int eccbytes;
1081                         int flips;
1082 
1083                         /* Read ECC bytes into our internal raw_buffer */
1084                         offset = nfc_geo->metadata_size * 8;
1085                         offset += ((8 * nfc_geo->ecc_chunk_size) + eccbits) * (i + 1);
1086                         offset -= eccbits;
1087                         bitoffset = offset % 8;
1088                         eccbytes = DIV_ROUND_UP(offset + eccbits, 8);
1089                         offset /= 8;
1090                         eccbytes -= offset;
1091                         chip->cmdfunc(mtd, NAND_CMD_RNDOUT, offset, -1);
1092                         chip->read_buf(mtd, eccbuf, eccbytes);
1093 
1094                         /*
1095                          * ECC data are not byte aligned and we may have
1096                          * in-band data in the first and last byte of
1097                          * eccbuf. Set non-eccbits to one so that
1098                          * nand_check_erased_ecc_chunk() does not count them
1099                          * as bitflips.
1100                          */
1101                         if (bitoffset)
1102                                 eccbuf[0] |= GENMASK(bitoffset - 1, 0);
1103 
1104                         bitoffset = (bitoffset + eccbits) % 8;
1105                         if (bitoffset)
1106                                 eccbuf[eccbytes - 1] |= GENMASK(7, bitoffset);
1107 
1108                         /*
1109                          * The ECC hardware has an uncorrectable ECC status
1110                          * code in case we have bitflips in an erased page. As
1111                          * nothing was written into this subpage the ECC is
1112                          * obviously wrong and we can not trust it. We assume
1113                          * at this point that we are reading an erased page and
1114                          * try to correct the bitflips in buffer up to
1115                          * ecc_strength bitflips. If this is a page with random
1116                          * data, we exceed this number of bitflips and have a
1117                          * ECC failure. Otherwise we use the corrected buffer.
1118                          */
1119                         if (i == 0) {
1120                                 /* The first block includes metadata */
1121                                 flips = nand_check_erased_ecc_chunk(
1122                                                 buf + i * nfc_geo->ecc_chunk_size,
1123                                                 nfc_geo->ecc_chunk_size,
1124                                                 eccbuf, eccbytes,
1125                                                 auxiliary_virt,
1126                                                 nfc_geo->metadata_size,
1127                                                 nfc_geo->ecc_strength);
1128                         } else {
1129                                 flips = nand_check_erased_ecc_chunk(
1130                                                 buf + i * nfc_geo->ecc_chunk_size,
1131                                                 nfc_geo->ecc_chunk_size,
1132                                                 eccbuf, eccbytes,
1133                                                 NULL, 0,
1134                                                 nfc_geo->ecc_strength);
1135                         }
1136 
1137                         if (flips > 0) {
1138                                 max_bitflips = max_t(unsigned int, max_bitflips,
1139                                                      flips);
1140                                 mtd->ecc_stats.corrected += flips;
1141                                 continue;
1142                         }
1143 
1144                         mtd->ecc_stats.failed++;
1145                         continue;
1146                 }
1147 
1148                 mtd->ecc_stats.corrected += *status;
1149                 max_bitflips = max_t(unsigned int, max_bitflips, *status);
1150         }
1151 
1152         if (oob_required) {
1153                 /*
1154                  * It's time to deliver the OOB bytes. See gpmi_ecc_read_oob()
1155                  * for details about our policy for delivering the OOB.
1156                  *
1157                  * We fill the caller's buffer with set bits, and then copy the
1158                  * block mark to th caller's buffer. Note that, if block mark
1159                  * swapping was necessary, it has already been done, so we can
1160                  * rely on the first byte of the auxiliary buffer to contain
1161                  * the block mark.
1162                  */
1163                 memset(chip->oob_poi, ~0, mtd->oobsize);
1164                 chip->oob_poi[0] = ((uint8_t *) auxiliary_virt)[0];
1165         }
1166 
1167         return max_bitflips;
1168 }
1169 
1170 /* Fake a virtual small page for the subpage read */
1171 static int gpmi_ecc_read_subpage(struct mtd_info *mtd, struct nand_chip *chip,
1172                         uint32_t offs, uint32_t len, uint8_t *buf, int page)
1173 {
1174         struct gpmi_nand_data *this = nand_get_controller_data(chip);
1175         void __iomem *bch_regs = this->resources.bch_regs;
1176         struct bch_geometry old_geo = this->bch_geometry;
1177         struct bch_geometry *geo = &this->bch_geometry;
1178         int size = chip->ecc.size; /* ECC chunk size */
1179         int meta, n, page_size;
1180         u32 r1_old, r2_old, r1_new, r2_new;
1181         unsigned int max_bitflips;
1182         int first, last, marker_pos;
1183         int ecc_parity_size;
1184         int col = 0;
1185         int old_swap_block_mark = this->swap_block_mark;
1186 
1187         /* The size of ECC parity */
1188         ecc_parity_size = geo->gf_len * geo->ecc_strength / 8;
1189 
1190         /* Align it with the chunk size */
1191         first = offs / size;
1192         last = (offs + len - 1) / size;
1193 
1194         if (this->swap_block_mark) {
1195                 /*
1196                  * Find the chunk which contains the Block Marker.
1197                  * If this chunk is in the range of [first, last],
1198                  * we have to read out the whole page.
1199                  * Why? since we had swapped the data at the position of Block
1200                  * Marker to the metadata which is bound with the chunk 0.
1201                  */
1202                 marker_pos = geo->block_mark_byte_offset / size;
1203                 if (last >= marker_pos && first <= marker_pos) {
1204                         dev_dbg(this->dev,
1205                                 "page:%d, first:%d, last:%d, marker at:%d\n",
1206                                 page, first, last, marker_pos);
1207                         return gpmi_ecc_read_page(mtd, chip, buf, 0, page);
1208                 }
1209         }
1210 
1211         meta = geo->metadata_size;
1212         if (first) {
1213                 col = meta + (size + ecc_parity_size) * first;
1214                 chip->cmdfunc(mtd, NAND_CMD_RNDOUT, col, -1);
1215 
1216                 meta = 0;
1217                 buf = buf + first * size;
1218         }
1219 
1220         /* Save the old environment */
1221         r1_old = r1_new = readl(bch_regs + HW_BCH_FLASH0LAYOUT0);
1222         r2_old = r2_new = readl(bch_regs + HW_BCH_FLASH0LAYOUT1);
1223 
1224         /* change the BCH registers and bch_geometry{} */
1225         n = last - first + 1;
1226         page_size = meta + (size + ecc_parity_size) * n;
1227 
1228         r1_new &= ~(BM_BCH_FLASH0LAYOUT0_NBLOCKS |
1229                         BM_BCH_FLASH0LAYOUT0_META_SIZE);
1230         r1_new |= BF_BCH_FLASH0LAYOUT0_NBLOCKS(n - 1)
1231                         | BF_BCH_FLASH0LAYOUT0_META_SIZE(meta);
1232         writel(r1_new, bch_regs + HW_BCH_FLASH0LAYOUT0);
1233 
1234         r2_new &= ~BM_BCH_FLASH0LAYOUT1_PAGE_SIZE;
1235         r2_new |= BF_BCH_FLASH0LAYOUT1_PAGE_SIZE(page_size);
1236         writel(r2_new, bch_regs + HW_BCH_FLASH0LAYOUT1);
1237 
1238         geo->ecc_chunk_count = n;
1239         geo->payload_size = n * size;
1240         geo->page_size = page_size;
1241         geo->auxiliary_status_offset = ALIGN(meta, 4);
1242 
1243         dev_dbg(this->dev, "page:%d(%d:%d)%d, chunk:(%d:%d), BCH PG size:%d\n",
1244                 page, offs, len, col, first, n, page_size);
1245 
1246         /* Read the subpage now */
1247         this->swap_block_mark = false;
1248         max_bitflips = gpmi_ecc_read_page(mtd, chip, buf, 0, page);
1249 
1250         /* Restore */
1251         writel(r1_old, bch_regs + HW_BCH_FLASH0LAYOUT0);
1252         writel(r2_old, bch_regs + HW_BCH_FLASH0LAYOUT1);
1253         this->bch_geometry = old_geo;
1254         this->swap_block_mark = old_swap_block_mark;
1255 
1256         return max_bitflips;
1257 }
1258 
1259 static int gpmi_ecc_write_page(struct mtd_info *mtd, struct nand_chip *chip,
1260                                 const uint8_t *buf, int oob_required, int page)
1261 {
1262         struct gpmi_nand_data *this = nand_get_controller_data(chip);
1263         struct bch_geometry *nfc_geo = &this->bch_geometry;
1264         const void *payload_virt;
1265         dma_addr_t payload_phys;
1266         const void *auxiliary_virt;
1267         dma_addr_t auxiliary_phys;
1268         int        ret;
1269 
1270         dev_dbg(this->dev, "ecc write page.\n");
1271         if (this->swap_block_mark) {
1272                 /*
1273                  * If control arrives here, we're doing block mark swapping.
1274                  * Since we can't modify the caller's buffers, we must copy them
1275                  * into our own.
1276                  */
1277                 memcpy(this->payload_virt, buf, mtd->writesize);
1278                 payload_virt = this->payload_virt;
1279                 payload_phys = this->payload_phys;
1280 
1281                 memcpy(this->auxiliary_virt, chip->oob_poi,
1282                                 nfc_geo->auxiliary_size);
1283                 auxiliary_virt = this->auxiliary_virt;
1284                 auxiliary_phys = this->auxiliary_phys;
1285 
1286                 /* Handle block mark swapping. */
1287                 block_mark_swapping(this,
1288                                 (void *)payload_virt, (void *)auxiliary_virt);
1289         } else {
1290                 /*
1291                  * If control arrives here, we're not doing block mark swapping,
1292                  * so we can to try and use the caller's buffers.
1293                  */
1294                 ret = send_page_prepare(this,
1295                                 buf, mtd->writesize,
1296                                 this->payload_virt, this->payload_phys,
1297                                 nfc_geo->payload_size,
1298                                 &payload_virt, &payload_phys);
1299                 if (ret) {
1300                         dev_err(this->dev, "Inadequate payload DMA buffer\n");
1301                         return 0;
1302                 }
1303 
1304                 ret = send_page_prepare(this,
1305                                 chip->oob_poi, mtd->oobsize,
1306                                 this->auxiliary_virt, this->auxiliary_phys,
1307                                 nfc_geo->auxiliary_size,
1308                                 &auxiliary_virt, &auxiliary_phys);
1309                 if (ret) {
1310                         dev_err(this->dev, "Inadequate auxiliary DMA buffer\n");
1311                         goto exit_auxiliary;
1312                 }
1313         }
1314 
1315         /* Ask the NFC. */
1316         ret = gpmi_send_page(this, payload_phys, auxiliary_phys);
1317         if (ret)
1318                 dev_err(this->dev, "Error in ECC-based write: %d\n", ret);
1319 
1320         if (!this->swap_block_mark) {
1321                 send_page_end(this, chip->oob_poi, mtd->oobsize,
1322                                 this->auxiliary_virt, this->auxiliary_phys,
1323                                 nfc_geo->auxiliary_size,
1324                                 auxiliary_virt, auxiliary_phys);
1325 exit_auxiliary:
1326                 send_page_end(this, buf, mtd->writesize,
1327                                 this->payload_virt, this->payload_phys,
1328                                 nfc_geo->payload_size,
1329                                 payload_virt, payload_phys);
1330         }
1331 
1332         return 0;
1333 }
1334 
1335 /*
1336  * There are several places in this driver where we have to handle the OOB and
1337  * block marks. This is the function where things are the most complicated, so
1338  * this is where we try to explain it all. All the other places refer back to
1339  * here.
1340  *
1341  * These are the rules, in order of decreasing importance:
1342  *
1343  * 1) Nothing the caller does can be allowed to imperil the block mark.
1344  *
1345  * 2) In read operations, the first byte of the OOB we return must reflect the
1346  *    true state of the block mark, no matter where that block mark appears in
1347  *    the physical page.
1348  *
1349  * 3) ECC-based read operations return an OOB full of set bits (since we never
1350  *    allow ECC-based writes to the OOB, it doesn't matter what ECC-based reads
1351  *    return).
1352  *
1353  * 4) "Raw" read operations return a direct view of the physical bytes in the
1354  *    page, using the conventional definition of which bytes are data and which
1355  *    are OOB. This gives the caller a way to see the actual, physical bytes
1356  *    in the page, without the distortions applied by our ECC engine.
1357  *
1358  *
1359  * What we do for this specific read operation depends on two questions:
1360  *
1361  * 1) Are we doing a "raw" read, or an ECC-based read?
1362  *
1363  * 2) Are we using block mark swapping or transcription?
1364  *
1365  * There are four cases, illustrated by the following Karnaugh map:
1366  *
1367  *                    |           Raw           |         ECC-based       |
1368  *       -------------+-------------------------+-------------------------+
1369  *                    | Read the conventional   |                         |
1370  *                    | OOB at the end of the   |                         |
1371  *       Swapping     | page and return it. It  |                         |
1372  *                    | contains exactly what   |                         |
1373  *                    | we want.                | Read the block mark and |
1374  *       -------------+-------------------------+ return it in a buffer   |
1375  *                    | Read the conventional   | full of set bits.       |
1376  *                    | OOB at the end of the   |                         |
1377  *                    | page and also the block |                         |
1378  *       Transcribing | mark in the metadata.   |                         |
1379  *                    | Copy the block mark     |                         |
1380  *                    | into the first byte of  |                         |
1381  *                    | the OOB.                |                         |
1382  *       -------------+-------------------------+-------------------------+
1383  *
1384  * Note that we break rule #4 in the Transcribing/Raw case because we're not
1385  * giving an accurate view of the actual, physical bytes in the page (we're
1386  * overwriting the block mark). That's OK because it's more important to follow
1387  * rule #2.
1388  *
1389  * It turns out that knowing whether we want an "ECC-based" or "raw" read is not
1390  * easy. When reading a page, for example, the NAND Flash MTD code calls our
1391  * ecc.read_page or ecc.read_page_raw function. Thus, the fact that MTD wants an
1392  * ECC-based or raw view of the page is implicit in which function it calls
1393  * (there is a similar pair of ECC-based/raw functions for writing).
1394  */
1395 static int gpmi_ecc_read_oob(struct mtd_info *mtd, struct nand_chip *chip,
1396                                 int page)
1397 {
1398         struct gpmi_nand_data *this = nand_get_controller_data(chip);
1399 
1400         dev_dbg(this->dev, "page number is %d\n", page);
1401         /* clear the OOB buffer */
1402         memset(chip->oob_poi, ~0, mtd->oobsize);
1403 
1404         /* Read out the conventional OOB. */
1405         chip->cmdfunc(mtd, NAND_CMD_READ0, mtd->writesize, page);
1406         chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
1407 
1408         /*
1409          * Now, we want to make sure the block mark is correct. In the
1410          * non-transcribing case (!GPMI_IS_MX23()), we already have it.
1411          * Otherwise, we need to explicitly read it.
1412          */
1413         if (GPMI_IS_MX23(this)) {
1414                 /* Read the block mark into the first byte of the OOB buffer. */
1415                 chip->cmdfunc(mtd, NAND_CMD_READ0, 0, page);
1416                 chip->oob_poi[0] = chip->read_byte(mtd);
1417         }
1418 
1419         return 0;
1420 }
1421 
1422 static int
1423 gpmi_ecc_write_oob(struct mtd_info *mtd, struct nand_chip *chip, int page)
1424 {
1425         struct mtd_oob_region of = { };
1426         int status = 0;
1427 
1428         /* Do we have available oob area? */
1429         mtd_ooblayout_free(mtd, 0, &of);
1430         if (!of.length)
1431                 return -EPERM;
1432 
1433         if (!nand_is_slc(chip))
1434                 return -EPERM;
1435 
1436         chip->cmdfunc(mtd, NAND_CMD_SEQIN, mtd->writesize + of.offset, page);
1437         chip->write_buf(mtd, chip->oob_poi + of.offset, of.length);
1438         chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
1439 
1440         status = chip->waitfunc(mtd, chip);
1441         return status & NAND_STATUS_FAIL ? -EIO : 0;
1442 }
1443 
1444 /*
1445  * This function reads a NAND page without involving the ECC engine (no HW
1446  * ECC correction).
1447  * The tricky part in the GPMI/BCH controller is that it stores ECC bits
1448  * inline (interleaved with payload DATA), and do not align data chunk on
1449  * byte boundaries.
1450  * We thus need to take care moving the payload data and ECC bits stored in the
1451  * page into the provided buffers, which is why we're using gpmi_copy_bits.
1452  *
1453  * See set_geometry_by_ecc_info inline comments to have a full description
1454  * of the layout used by the GPMI controller.
1455  */
1456 static int gpmi_ecc_read_page_raw(struct mtd_info *mtd,
1457                                   struct nand_chip *chip, uint8_t *buf,
1458                                   int oob_required, int page)
1459 {
1460         struct gpmi_nand_data *this = nand_get_controller_data(chip);
1461         struct bch_geometry *nfc_geo = &this->bch_geometry;
1462         int eccsize = nfc_geo->ecc_chunk_size;
1463         int eccbits = nfc_geo->ecc_strength * nfc_geo->gf_len;
1464         u8 *tmp_buf = this->raw_buffer;
1465         size_t src_bit_off;
1466         size_t oob_bit_off;
1467         size_t oob_byte_off;
1468         uint8_t *oob = chip->oob_poi;
1469         int step;
1470 
1471         chip->read_buf(mtd, tmp_buf,
1472                        mtd->writesize + mtd->oobsize);
1473 
1474         /*
1475          * If required, swap the bad block marker and the data stored in the
1476          * metadata section, so that we don't wrongly consider a block as bad.
1477          *
1478          * See the layout description for a detailed explanation on why this
1479          * is needed.
1480          */
1481         if (this->swap_block_mark) {
1482                 u8 swap = tmp_buf[0];
1483 
1484                 tmp_buf[0] = tmp_buf[mtd->writesize];
1485                 tmp_buf[mtd->writesize] = swap;
1486         }
1487 
1488         /*
1489          * Copy the metadata section into the oob buffer (this section is
1490          * guaranteed to be aligned on a byte boundary).
1491          */
1492         if (oob_required)
1493                 memcpy(oob, tmp_buf, nfc_geo->metadata_size);
1494 
1495         oob_bit_off = nfc_geo->metadata_size * 8;
1496         src_bit_off = oob_bit_off;
1497 
1498         /* Extract interleaved payload data and ECC bits */
1499         for (step = 0; step < nfc_geo->ecc_chunk_count; step++) {
1500                 if (buf)
1501                         gpmi_copy_bits(buf, step * eccsize * 8,
1502                                        tmp_buf, src_bit_off,
1503                                        eccsize * 8);
1504                 src_bit_off += eccsize * 8;
1505 
1506                 /* Align last ECC block to align a byte boundary */
1507                 if (step == nfc_geo->ecc_chunk_count - 1 &&
1508                     (oob_bit_off + eccbits) % 8)
1509                         eccbits += 8 - ((oob_bit_off + eccbits) % 8);
1510 
1511                 if (oob_required)
1512                         gpmi_copy_bits(oob, oob_bit_off,
1513                                        tmp_buf, src_bit_off,
1514                                        eccbits);
1515 
1516                 src_bit_off += eccbits;
1517                 oob_bit_off += eccbits;
1518         }
1519 
1520         if (oob_required) {
1521                 oob_byte_off = oob_bit_off / 8;
1522 
1523                 if (oob_byte_off < mtd->oobsize)
1524                         memcpy(oob + oob_byte_off,
1525                                tmp_buf + mtd->writesize + oob_byte_off,
1526                                mtd->oobsize - oob_byte_off);
1527         }
1528 
1529         return 0;
1530 }
1531 
1532 /*
1533  * This function writes a NAND page without involving the ECC engine (no HW
1534  * ECC generation).
1535  * The tricky part in the GPMI/BCH controller is that it stores ECC bits
1536  * inline (interleaved with payload DATA), and do not align data chunk on
1537  * byte boundaries.
1538  * We thus need to take care moving the OOB area at the right place in the
1539  * final page, which is why we're using gpmi_copy_bits.
1540  *
1541  * See set_geometry_by_ecc_info inline comments to have a full description
1542  * of the layout used by the GPMI controller.
1543  */
1544 static int gpmi_ecc_write_page_raw(struct mtd_info *mtd,
1545                                    struct nand_chip *chip,
1546                                    const uint8_t *buf,
1547                                    int oob_required, int page)
1548 {
1549         struct gpmi_nand_data *this = nand_get_controller_data(chip);
1550         struct bch_geometry *nfc_geo = &this->bch_geometry;
1551         int eccsize = nfc_geo->ecc_chunk_size;
1552         int eccbits = nfc_geo->ecc_strength * nfc_geo->gf_len;
1553         u8 *tmp_buf = this->raw_buffer;
1554         uint8_t *oob = chip->oob_poi;
1555         size_t dst_bit_off;
1556         size_t oob_bit_off;
1557         size_t oob_byte_off;
1558         int step;
1559 
1560         /*
1561          * Initialize all bits to 1 in case we don't have a buffer for the
1562          * payload or oob data in order to leave unspecified bits of data
1563          * to their initial state.
1564          */
1565         if (!buf || !oob_required)
1566                 memset(tmp_buf, 0xff, mtd->writesize + mtd->oobsize);
1567 
1568         /*
1569          * First copy the metadata section (stored in oob buffer) at the
1570          * beginning of the page, as imposed by the GPMI layout.
1571          */
1572         memcpy(tmp_buf, oob, nfc_geo->metadata_size);
1573         oob_bit_off = nfc_geo->metadata_size * 8;
1574         dst_bit_off = oob_bit_off;
1575 
1576         /* Interleave payload data and ECC bits */
1577         for (step = 0; step < nfc_geo->ecc_chunk_count; step++) {
1578                 if (buf)
1579                         gpmi_copy_bits(tmp_buf, dst_bit_off,
1580                                        buf, step * eccsize * 8, eccsize * 8);
1581                 dst_bit_off += eccsize * 8;
1582 
1583                 /* Align last ECC block to align a byte boundary */
1584                 if (step == nfc_geo->ecc_chunk_count - 1 &&
1585                     (oob_bit_off + eccbits) % 8)
1586                         eccbits += 8 - ((oob_bit_off + eccbits) % 8);
1587 
1588                 if (oob_required)
1589                         gpmi_copy_bits(tmp_buf, dst_bit_off,
1590                                        oob, oob_bit_off, eccbits);
1591 
1592                 dst_bit_off += eccbits;
1593                 oob_bit_off += eccbits;
1594         }
1595 
1596         oob_byte_off = oob_bit_off / 8;
1597 
1598         if (oob_required && oob_byte_off < mtd->oobsize)
1599                 memcpy(tmp_buf + mtd->writesize + oob_byte_off,
1600                        oob + oob_byte_off, mtd->oobsize - oob_byte_off);
1601 
1602         /*
1603          * If required, swap the bad block marker and the first byte of the
1604          * metadata section, so that we don't modify the bad block marker.
1605          *
1606          * See the layout description for a detailed explanation on why this
1607          * is needed.
1608          */
1609         if (this->swap_block_mark) {
1610                 u8 swap = tmp_buf[0];
1611 
1612                 tmp_buf[0] = tmp_buf[mtd->writesize];
1613                 tmp_buf[mtd->writesize] = swap;
1614         }
1615 
1616         chip->write_buf(mtd, tmp_buf, mtd->writesize + mtd->oobsize);
1617 
1618         return 0;
1619 }
1620 
1621 static int gpmi_ecc_read_oob_raw(struct mtd_info *mtd, struct nand_chip *chip,
1622                                  int page)
1623 {
1624         chip->cmdfunc(mtd, NAND_CMD_READ0, 0, page);
1625 
1626         return gpmi_ecc_read_page_raw(mtd, chip, NULL, 1, page);
1627 }
1628 
1629 static int gpmi_ecc_write_oob_raw(struct mtd_info *mtd, struct nand_chip *chip,
1630                                  int page)
1631 {
1632         chip->cmdfunc(mtd, NAND_CMD_SEQIN, 0, page);
1633 
1634         return gpmi_ecc_write_page_raw(mtd, chip, NULL, 1, page);
1635 }
1636 
1637 static int gpmi_block_markbad(struct mtd_info *mtd, loff_t ofs)
1638 {
1639         struct nand_chip *chip = mtd_to_nand(mtd);
1640         struct gpmi_nand_data *this = nand_get_controller_data(chip);
1641         int ret = 0;
1642         uint8_t *block_mark;
1643         int column, page, status, chipnr;
1644 
1645         chipnr = (int)(ofs >> chip->chip_shift);
1646         chip->select_chip(mtd, chipnr);
1647 
1648         column = !GPMI_IS_MX23(this) ? mtd->writesize : 0;
1649 
1650         /* Write the block mark. */
1651         block_mark = this->data_buffer_dma;
1652         block_mark[0] = 0; /* bad block marker */
1653 
1654         /* Shift to get page */
1655         page = (int)(ofs >> chip->page_shift);
1656 
1657         chip->cmdfunc(mtd, NAND_CMD_SEQIN, column, page);
1658         chip->write_buf(mtd, block_mark, 1);
1659         chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
1660 
1661         status = chip->waitfunc(mtd, chip);
1662         if (status & NAND_STATUS_FAIL)
1663                 ret = -EIO;
1664 
1665         chip->select_chip(mtd, -1);
1666 
1667         return ret;
1668 }
1669 
1670 static int nand_boot_set_geometry(struct gpmi_nand_data *this)
1671 {
1672         struct boot_rom_geometry *geometry = &this->rom_geometry;
1673 
1674         /*
1675          * Set the boot block stride size.
1676          *
1677          * In principle, we should be reading this from the OTP bits, since
1678          * that's where the ROM is going to get it. In fact, we don't have any
1679          * way to read the OTP bits, so we go with the default and hope for the
1680          * best.
1681          */
1682         geometry->stride_size_in_pages = 64;
1683 
1684         /*
1685          * Set the search area stride exponent.
1686          *
1687          * In principle, we should be reading this from the OTP bits, since
1688          * that's where the ROM is going to get it. In fact, we don't have any
1689          * way to read the OTP bits, so we go with the default and hope for the
1690          * best.
1691          */
1692         geometry->search_area_stride_exponent = 2;
1693         return 0;
1694 }
1695 
1696 static const char  *fingerprint = "STMP";
1697 static int mx23_check_transcription_stamp(struct gpmi_nand_data *this)
1698 {
1699         struct boot_rom_geometry *rom_geo = &this->rom_geometry;
1700         struct device *dev = this->dev;
1701         struct nand_chip *chip = &this->nand;
1702         struct mtd_info *mtd = nand_to_mtd(chip);
1703         unsigned int search_area_size_in_strides;
1704         unsigned int stride;
1705         unsigned int page;
1706         uint8_t *buffer = chip->buffers->databuf;
1707         int saved_chip_number;
1708         int found_an_ncb_fingerprint = false;
1709 
1710         /* Compute the number of strides in a search area. */
1711         search_area_size_in_strides = 1 << rom_geo->search_area_stride_exponent;
1712 
1713         saved_chip_number = this->current_chip;
1714         chip->select_chip(mtd, 0);
1715 
1716         /*
1717          * Loop through the first search area, looking for the NCB fingerprint.
1718          */
1719         dev_dbg(dev, "Scanning for an NCB fingerprint...\n");
1720 
1721         for (stride = 0; stride < search_area_size_in_strides; stride++) {
1722                 /* Compute the page addresses. */
1723                 page = stride * rom_geo->stride_size_in_pages;
1724 
1725                 dev_dbg(dev, "Looking for a fingerprint in page 0x%x\n", page);
1726 
1727                 /*
1728                  * Read the NCB fingerprint. The fingerprint is four bytes long
1729                  * and starts in the 12th byte of the page.
1730                  */
1731                 chip->cmdfunc(mtd, NAND_CMD_READ0, 12, page);
1732                 chip->read_buf(mtd, buffer, strlen(fingerprint));
1733 
1734                 /* Look for the fingerprint. */
1735                 if (!memcmp(buffer, fingerprint, strlen(fingerprint))) {
1736                         found_an_ncb_fingerprint = true;
1737                         break;
1738                 }
1739 
1740         }
1741 
1742         chip->select_chip(mtd, saved_chip_number);
1743 
1744         if (found_an_ncb_fingerprint)
1745                 dev_dbg(dev, "\tFound a fingerprint\n");
1746         else
1747                 dev_dbg(dev, "\tNo fingerprint found\n");
1748         return found_an_ncb_fingerprint;
1749 }
1750 
1751 /* Writes a transcription stamp. */
1752 static int mx23_write_transcription_stamp(struct gpmi_nand_data *this)
1753 {
1754         struct device *dev = this->dev;
1755         struct boot_rom_geometry *rom_geo = &this->rom_geometry;
1756         struct nand_chip *chip = &this->nand;
1757         struct mtd_info *mtd = nand_to_mtd(chip);
1758         unsigned int block_size_in_pages;
1759         unsigned int search_area_size_in_strides;
1760         unsigned int search_area_size_in_pages;
1761         unsigned int search_area_size_in_blocks;
1762         unsigned int block;
1763         unsigned int stride;
1764         unsigned int page;
1765         uint8_t      *buffer = chip->buffers->databuf;
1766         int saved_chip_number;
1767         int status;
1768 
1769         /* Compute the search area geometry. */
1770         block_size_in_pages = mtd->erasesize / mtd->writesize;
1771         search_area_size_in_strides = 1 << rom_geo->search_area_stride_exponent;
1772         search_area_size_in_pages = search_area_size_in_strides *
1773                                         rom_geo->stride_size_in_pages;
1774         search_area_size_in_blocks =
1775                   (search_area_size_in_pages + (block_size_in_pages - 1)) /
1776                                     block_size_in_pages;
1777 
1778         dev_dbg(dev, "Search Area Geometry :\n");
1779         dev_dbg(dev, "\tin Blocks : %u\n", search_area_size_in_blocks);
1780         dev_dbg(dev, "\tin Strides: %u\n", search_area_size_in_strides);
1781         dev_dbg(dev, "\tin Pages  : %u\n", search_area_size_in_pages);
1782 
1783         /* Select chip 0. */
1784         saved_chip_number = this->current_chip;
1785         chip->select_chip(mtd, 0);
1786 
1787         /* Loop over blocks in the first search area, erasing them. */
1788         dev_dbg(dev, "Erasing the search area...\n");
1789 
1790         for (block = 0; block < search_area_size_in_blocks; block++) {
1791                 /* Compute the page address. */
1792                 page = block * block_size_in_pages;
1793 
1794                 /* Erase this block. */
1795                 dev_dbg(dev, "\tErasing block 0x%x\n", block);
1796                 chip->cmdfunc(mtd, NAND_CMD_ERASE1, -1, page);
1797                 chip->cmdfunc(mtd, NAND_CMD_ERASE2, -1, -1);
1798 
1799                 /* Wait for the erase to finish. */
1800                 status = chip->waitfunc(mtd, chip);
1801                 if (status & NAND_STATUS_FAIL)
1802                         dev_err(dev, "[%s] Erase failed.\n", __func__);
1803         }
1804 
1805         /* Write the NCB fingerprint into the page buffer. */
1806         memset(buffer, ~0, mtd->writesize);
1807         memcpy(buffer + 12, fingerprint, strlen(fingerprint));
1808 
1809         /* Loop through the first search area, writing NCB fingerprints. */
1810         dev_dbg(dev, "Writing NCB fingerprints...\n");
1811         for (stride = 0; stride < search_area_size_in_strides; stride++) {
1812                 /* Compute the page addresses. */
1813                 page = stride * rom_geo->stride_size_in_pages;
1814 
1815                 /* Write the first page of the current stride. */
1816                 dev_dbg(dev, "Writing an NCB fingerprint in page 0x%x\n", page);
1817                 chip->cmdfunc(mtd, NAND_CMD_SEQIN, 0x00, page);
1818                 chip->ecc.write_page_raw(mtd, chip, buffer, 0, page);
1819                 chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
1820 
1821                 /* Wait for the write to finish. */
1822                 status = chip->waitfunc(mtd, chip);
1823                 if (status & NAND_STATUS_FAIL)
1824                         dev_err(dev, "[%s] Write failed.\n", __func__);
1825         }
1826 
1827         /* Deselect chip 0. */
1828         chip->select_chip(mtd, saved_chip_number);
1829         return 0;
1830 }
1831 
1832 static int mx23_boot_init(struct gpmi_nand_data  *this)
1833 {
1834         struct device *dev = this->dev;
1835         struct nand_chip *chip = &this->nand;
1836         struct mtd_info *mtd = nand_to_mtd(chip);
1837         unsigned int block_count;
1838         unsigned int block;
1839         int     chipnr;
1840         int     page;
1841         loff_t  byte;
1842         uint8_t block_mark;
1843         int     ret = 0;
1844 
1845         /*
1846          * If control arrives here, we can't use block mark swapping, which
1847          * means we're forced to use transcription. First, scan for the
1848          * transcription stamp. If we find it, then we don't have to do
1849          * anything -- the block marks are already transcribed.
1850          */
1851         if (mx23_check_transcription_stamp(this))
1852                 return 0;
1853 
1854         /*
1855          * If control arrives here, we couldn't find a transcription stamp, so
1856          * so we presume the block marks are in the conventional location.
1857          */
1858         dev_dbg(dev, "Transcribing bad block marks...\n");
1859 
1860         /* Compute the number of blocks in the entire medium. */
1861         block_count = chip->chipsize >> chip->phys_erase_shift;
1862 
1863         /*
1864          * Loop over all the blocks in the medium, transcribing block marks as
1865          * we go.
1866          */
1867         for (block = 0; block < block_count; block++) {
1868                 /*
1869                  * Compute the chip, page and byte addresses for this block's
1870                  * conventional mark.
1871                  */
1872                 chipnr = block >> (chip->chip_shift - chip->phys_erase_shift);
1873                 page = block << (chip->phys_erase_shift - chip->page_shift);
1874                 byte = block <<  chip->phys_erase_shift;
1875 
1876                 /* Send the command to read the conventional block mark. */
1877                 chip->select_chip(mtd, chipnr);
1878                 chip->cmdfunc(mtd, NAND_CMD_READ0, mtd->writesize, page);
1879                 block_mark = chip->read_byte(mtd);
1880                 chip->select_chip(mtd, -1);
1881 
1882                 /*
1883                  * Check if the block is marked bad. If so, we need to mark it
1884                  * again, but this time the result will be a mark in the
1885                  * location where we transcribe block marks.
1886                  */
1887                 if (block_mark != 0xff) {
1888                         dev_dbg(dev, "Transcribing mark in block %u\n", block);
1889                         ret = chip->block_markbad(mtd, byte);
1890                         if (ret)
1891                                 dev_err(dev,
1892                                         "Failed to mark block bad with ret %d\n",
1893                                         ret);
1894                 }
1895         }
1896 
1897         /* Write the stamp that indicates we've transcribed the block marks. */
1898         mx23_write_transcription_stamp(this);
1899         return 0;
1900 }
1901 
1902 static int nand_boot_init(struct gpmi_nand_data  *this)
1903 {
1904         nand_boot_set_geometry(this);
1905 
1906         /* This is ROM arch-specific initilization before the BBT scanning. */
1907         if (GPMI_IS_MX23(this))
1908                 return mx23_boot_init(this);
1909         return 0;
1910 }
1911 
1912 static int gpmi_set_geometry(struct gpmi_nand_data *this)
1913 {
1914         int ret;
1915 
1916         /* Free the temporary DMA memory for reading ID. */
1917         gpmi_free_dma_buffer(this);
1918 
1919         /* Set up the NFC geometry which is used by BCH. */
1920         ret = bch_set_geometry(this);
1921         if (ret) {
1922                 dev_err(this->dev, "Error setting BCH geometry : %d\n", ret);
1923                 return ret;
1924         }
1925 
1926         /* Alloc the new DMA buffers according to the pagesize and oobsize */
1927         return gpmi_alloc_dma_buffer(this);
1928 }
1929 
1930 static void gpmi_nand_exit(struct gpmi_nand_data *this)
1931 {
1932         nand_release(nand_to_mtd(&this->nand));
1933         gpmi_free_dma_buffer(this);
1934 }
1935 
1936 static int gpmi_init_last(struct gpmi_nand_data *this)
1937 {
1938         struct nand_chip *chip = &this->nand;
1939         struct mtd_info *mtd = nand_to_mtd(chip);
1940         struct nand_ecc_ctrl *ecc = &chip->ecc;
1941         struct bch_geometry *bch_geo = &this->bch_geometry;
1942         int ret;
1943 
1944         /* Set up the medium geometry */
1945         ret = gpmi_set_geometry(this);
1946         if (ret)
1947                 return ret;
1948 
1949         /* Init the nand_ecc_ctrl{} */
1950         ecc->read_page  = gpmi_ecc_read_page;
1951         ecc->write_page = gpmi_ecc_write_page;
1952         ecc->read_oob   = gpmi_ecc_read_oob;
1953         ecc->write_oob  = gpmi_ecc_write_oob;
1954         ecc->read_page_raw = gpmi_ecc_read_page_raw;
1955         ecc->write_page_raw = gpmi_ecc_write_page_raw;
1956         ecc->read_oob_raw = gpmi_ecc_read_oob_raw;
1957         ecc->write_oob_raw = gpmi_ecc_write_oob_raw;
1958         ecc->mode       = NAND_ECC_HW;
1959         ecc->size       = bch_geo->ecc_chunk_size;
1960         ecc->strength   = bch_geo->ecc_strength;
1961         mtd_set_ooblayout(mtd, &gpmi_ooblayout_ops);
1962 
1963         /*
1964          * We only enable the subpage read when:
1965          *  (1) the chip is imx6, and
1966          *  (2) the size of the ECC parity is byte aligned.
1967          */
1968         if (GPMI_IS_MX6(this) &&
1969                 ((bch_geo->gf_len * bch_geo->ecc_strength) % 8) == 0) {
1970                 ecc->read_subpage = gpmi_ecc_read_subpage;
1971                 chip->options |= NAND_SUBPAGE_READ;
1972         }
1973 
1974         /*
1975          * Can we enable the extra features? such as EDO or Sync mode.
1976          *
1977          * We do not check the return value now. That's means if we fail in
1978          * enable the extra features, we still can run in the normal way.
1979          */
1980         gpmi_extra_init(this);
1981 
1982         return 0;
1983 }
1984 
1985 static int gpmi_nand_init(struct gpmi_nand_data *this)
1986 {
1987         struct nand_chip *chip = &this->nand;
1988         struct mtd_info  *mtd = nand_to_mtd(chip);
1989         int ret;
1990 
1991         /* init current chip */
1992         this->current_chip      = -1;
1993 
1994         /* init the MTD data structures */
1995         mtd->name               = "gpmi-nand";
1996         mtd->dev.parent         = this->dev;
1997 
1998         /* init the nand_chip{}, we don't support a 16-bit NAND Flash bus. */
1999         nand_set_controller_data(chip, this);
2000         nand_set_flash_node(chip, this->pdev->dev.of_node);
2001         chip->select_chip       = gpmi_select_chip;
2002         chip->cmd_ctrl          = gpmi_cmd_ctrl;
2003         chip->dev_ready         = gpmi_dev_ready;
2004         chip->read_byte         = gpmi_read_byte;
2005         chip->read_buf          = gpmi_read_buf;
2006         chip->write_buf         = gpmi_write_buf;
2007         chip->badblock_pattern  = &gpmi_bbt_descr;
2008         chip->block_markbad     = gpmi_block_markbad;
2009         chip->options           |= NAND_NO_SUBPAGE_WRITE;
2010 
2011         /* Set up swap_block_mark, must be set before the gpmi_set_geometry() */
2012         this->swap_block_mark = !GPMI_IS_MX23(this);
2013 
2014         /*
2015          * Allocate a temporary DMA buffer for reading ID in the
2016          * nand_scan_ident().
2017          */
2018         this->bch_geometry.payload_size = 1024;
2019         this->bch_geometry.auxiliary_size = 128;
2020         ret = gpmi_alloc_dma_buffer(this);
2021         if (ret)
2022                 goto err_out;
2023 
2024         ret = nand_scan_ident(mtd, GPMI_IS_MX6(this) ? 2 : 1, NULL);
2025         if (ret)
2026                 goto err_out;
2027 
2028         if (chip->bbt_options & NAND_BBT_USE_FLASH) {
2029                 chip->bbt_options |= NAND_BBT_NO_OOB;
2030 
2031                 if (of_property_read_bool(this->dev->of_node,
2032                                                 "fsl,no-blockmark-swap"))
2033                         this->swap_block_mark = false;
2034         }
2035         dev_dbg(this->dev, "Blockmark swapping %sabled\n",
2036                 this->swap_block_mark ? "en" : "dis");
2037 
2038         ret = gpmi_init_last(this);
2039         if (ret)
2040                 goto err_out;
2041 
2042         chip->options |= NAND_SKIP_BBTSCAN;
2043         ret = nand_scan_tail(mtd);
2044         if (ret)
2045                 goto err_out;
2046 
2047         ret = nand_boot_init(this);
2048         if (ret)
2049                 goto err_out;
2050         ret = chip->scan_bbt(mtd);
2051         if (ret)
2052                 goto err_out;
2053 
2054         ret = mtd_device_register(mtd, NULL, 0);
2055         if (ret)
2056                 goto err_out;
2057         return 0;
2058 
2059 err_out:
2060         gpmi_nand_exit(this);
2061         return ret;
2062 }
2063 
2064 static const struct of_device_id gpmi_nand_id_table[] = {
2065         {
2066                 .compatible = "fsl,imx23-gpmi-nand",
2067                 .data = &gpmi_devdata_imx23,
2068         }, {
2069                 .compatible = "fsl,imx28-gpmi-nand",
2070                 .data = &gpmi_devdata_imx28,
2071         }, {
2072                 .compatible = "fsl,imx6q-gpmi-nand",
2073                 .data = &gpmi_devdata_imx6q,
2074         }, {
2075                 .compatible = "fsl,imx6sx-gpmi-nand",
2076                 .data = &gpmi_devdata_imx6sx,
2077         }, {}
2078 };
2079 MODULE_DEVICE_TABLE(of, gpmi_nand_id_table);
2080 
2081 static int gpmi_nand_probe(struct platform_device *pdev)
2082 {
2083         struct gpmi_nand_data *this;
2084         const struct of_device_id *of_id;
2085         int ret;
2086 
2087         this = devm_kzalloc(&pdev->dev, sizeof(*this), GFP_KERNEL);
2088         if (!this)
2089                 return -ENOMEM;
2090 
2091         of_id = of_match_device(gpmi_nand_id_table, &pdev->dev);
2092         if (of_id) {
2093                 this->devdata = of_id->data;
2094         } else {
2095                 dev_err(&pdev->dev, "Failed to find the right device id.\n");
2096                 return -ENODEV;
2097         }
2098 
2099         platform_set_drvdata(pdev, this);
2100         this->pdev  = pdev;
2101         this->dev   = &pdev->dev;
2102 
2103         ret = acquire_resources(this);
2104         if (ret)
2105                 goto exit_acquire_resources;
2106 
2107         ret = init_hardware(this);
2108         if (ret)
2109                 goto exit_nfc_init;
2110 
2111         ret = gpmi_nand_init(this);
2112         if (ret)
2113                 goto exit_nfc_init;
2114 
2115         dev_info(this->dev, "driver registered.\n");
2116 
2117         return 0;
2118 
2119 exit_nfc_init:
2120         release_resources(this);
2121 exit_acquire_resources:
2122 
2123         return ret;
2124 }
2125 
2126 static int gpmi_nand_remove(struct platform_device *pdev)
2127 {
2128         struct gpmi_nand_data *this = platform_get_drvdata(pdev);
2129 
2130         gpmi_nand_exit(this);
2131         release_resources(this);
2132         return 0;
2133 }
2134 
2135 #ifdef CONFIG_PM_SLEEP
2136 static int gpmi_pm_suspend(struct device *dev)
2137 {
2138         struct gpmi_nand_data *this = dev_get_drvdata(dev);
2139 
2140         release_dma_channels(this);
2141         return 0;
2142 }
2143 
2144 static int gpmi_pm_resume(struct device *dev)
2145 {
2146         struct gpmi_nand_data *this = dev_get_drvdata(dev);
2147         int ret;
2148 
2149         ret = acquire_dma_channels(this);
2150         if (ret < 0)
2151                 return ret;
2152 
2153         /* re-init the GPMI registers */
2154         this->flags &= ~GPMI_TIMING_INIT_OK;
2155         ret = gpmi_init(this);
2156         if (ret) {
2157                 dev_err(this->dev, "Error setting GPMI : %d\n", ret);
2158                 return ret;
2159         }
2160 
2161         /* re-init the BCH registers */
2162         ret = bch_set_geometry(this);
2163         if (ret) {
2164                 dev_err(this->dev, "Error setting BCH : %d\n", ret);
2165                 return ret;
2166         }
2167 
2168         /* re-init others */
2169         gpmi_extra_init(this);
2170 
2171         return 0;
2172 }
2173 #endif /* CONFIG_PM_SLEEP */
2174 
2175 static const struct dev_pm_ops gpmi_pm_ops = {
2176         SET_SYSTEM_SLEEP_PM_OPS(gpmi_pm_suspend, gpmi_pm_resume)
2177 };
2178 
2179 static struct platform_driver gpmi_nand_driver = {
2180         .driver = {
2181                 .name = "gpmi-nand",
2182                 .pm = &gpmi_pm_ops,
2183                 .of_match_table = gpmi_nand_id_table,
2184         },
2185         .probe   = gpmi_nand_probe,
2186         .remove  = gpmi_nand_remove,
2187 };
2188 module_platform_driver(gpmi_nand_driver);
2189 
2190 MODULE_AUTHOR("Freescale Semiconductor, Inc.");
2191 MODULE_DESCRIPTION("i.MX GPMI NAND Flash Controller Driver");
2192 MODULE_LICENSE("GPL");
2193 

This page was automatically generated by LXR 0.3.1 (source).  •  Linux is a registered trademark of Linus Torvalds  •  Contact us