1 /*
2 * Copyright (C) 2009-2010, Lars-Peter Clausen <lars@metafoo.de>
3 * JZ4740 SoC NAND controller driver
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License as published by the
7 * Free Software Foundation; either version 2 of the License, or (at your
8 * option) any later version.
9 *
10 * You should have received a copy of the GNU General Public License along
11 * with this program; if not, write to the Free Software Foundation, Inc.,
12 * 675 Mass Ave, Cambridge, MA 02139, USA.
13 *
14 */
15
16 #include <linux/ioport.h>
17 #include <linux/kernel.h>
18 #include <linux/module.h>
19 #include <linux/platform_device.h>
20 #include <linux/slab.h>
21
22 #include <linux/mtd/mtd.h>
23 #include <linux/mtd/nand.h>
24 #include <linux/mtd/partitions.h>
25
26 #include <linux/gpio.h>
27
28 #include <asm/mach-jz4740/jz4740_nand.h>
29
30 #define JZ_REG_NAND_CTRL 0x50
31 #define JZ_REG_NAND_ECC_CTRL 0x100
32 #define JZ_REG_NAND_DATA 0x104
33 #define JZ_REG_NAND_PAR0 0x108
34 #define JZ_REG_NAND_PAR1 0x10C
35 #define JZ_REG_NAND_PAR2 0x110
36 #define JZ_REG_NAND_IRQ_STAT 0x114
37 #define JZ_REG_NAND_IRQ_CTRL 0x118
38 #define JZ_REG_NAND_ERR(x) (0x11C + ((x) << 2))
39
40 #define JZ_NAND_ECC_CTRL_PAR_READY BIT(4)
41 #define JZ_NAND_ECC_CTRL_ENCODING BIT(3)
42 #define JZ_NAND_ECC_CTRL_RS BIT(2)
43 #define JZ_NAND_ECC_CTRL_RESET BIT(1)
44 #define JZ_NAND_ECC_CTRL_ENABLE BIT(0)
45
46 #define JZ_NAND_STATUS_ERR_COUNT (BIT(31) | BIT(30) | BIT(29))
47 #define JZ_NAND_STATUS_PAD_FINISH BIT(4)
48 #define JZ_NAND_STATUS_DEC_FINISH BIT(3)
49 #define JZ_NAND_STATUS_ENC_FINISH BIT(2)
50 #define JZ_NAND_STATUS_UNCOR_ERROR BIT(1)
51 #define JZ_NAND_STATUS_ERROR BIT(0)
52
53 #define JZ_NAND_CTRL_ENABLE_CHIP(x) BIT((x) << 1)
54 #define JZ_NAND_CTRL_ASSERT_CHIP(x) BIT(((x) << 1) + 1)
55 #define JZ_NAND_CTRL_ASSERT_CHIP_MASK 0xaa
56
57 #define JZ_NAND_MEM_CMD_OFFSET 0x08000
58 #define JZ_NAND_MEM_ADDR_OFFSET 0x10000
59
60 struct jz_nand {
61 struct mtd_info mtd;
62 struct nand_chip chip;
63 void __iomem *base;
64 struct resource *mem;
65
66 unsigned char banks[JZ_NAND_NUM_BANKS];
67 void __iomem *bank_base[JZ_NAND_NUM_BANKS];
68 struct resource *bank_mem[JZ_NAND_NUM_BANKS];
69
70 int selected_bank;
71
72 struct jz_nand_platform_data *pdata;
73 bool is_reading;
74 };
75
mtd_to_jz_nand(struct mtd_info * mtd)76 static inline struct jz_nand *mtd_to_jz_nand(struct mtd_info *mtd)
77 {
78 return container_of(mtd, struct jz_nand, mtd);
79 }
80
jz_nand_select_chip(struct mtd_info * mtd,int chipnr)81 static void jz_nand_select_chip(struct mtd_info *mtd, int chipnr)
82 {
83 struct jz_nand *nand = mtd_to_jz_nand(mtd);
84 struct nand_chip *chip = mtd->priv;
85 uint32_t ctrl;
86 int banknr;
87
88 ctrl = readl(nand->base + JZ_REG_NAND_CTRL);
89 ctrl &= ~JZ_NAND_CTRL_ASSERT_CHIP_MASK;
90
91 if (chipnr == -1) {
92 banknr = -1;
93 } else {
94 banknr = nand->banks[chipnr] - 1;
95 chip->IO_ADDR_R = nand->bank_base[banknr];
96 chip->IO_ADDR_W = nand->bank_base[banknr];
97 }
98 writel(ctrl, nand->base + JZ_REG_NAND_CTRL);
99
100 nand->selected_bank = banknr;
101 }
102
jz_nand_cmd_ctrl(struct mtd_info * mtd,int dat,unsigned int ctrl)103 static void jz_nand_cmd_ctrl(struct mtd_info *mtd, int dat, unsigned int ctrl)
104 {
105 struct jz_nand *nand = mtd_to_jz_nand(mtd);
106 struct nand_chip *chip = mtd->priv;
107 uint32_t reg;
108 void __iomem *bank_base = nand->bank_base[nand->selected_bank];
109
110 BUG_ON(nand->selected_bank < 0);
111
112 if (ctrl & NAND_CTRL_CHANGE) {
113 BUG_ON((ctrl & NAND_ALE) && (ctrl & NAND_CLE));
114 if (ctrl & NAND_ALE)
115 bank_base += JZ_NAND_MEM_ADDR_OFFSET;
116 else if (ctrl & NAND_CLE)
117 bank_base += JZ_NAND_MEM_CMD_OFFSET;
118 chip->IO_ADDR_W = bank_base;
119
120 reg = readl(nand->base + JZ_REG_NAND_CTRL);
121 if (ctrl & NAND_NCE)
122 reg |= JZ_NAND_CTRL_ASSERT_CHIP(nand->selected_bank);
123 else
124 reg &= ~JZ_NAND_CTRL_ASSERT_CHIP(nand->selected_bank);
125 writel(reg, nand->base + JZ_REG_NAND_CTRL);
126 }
127 if (dat != NAND_CMD_NONE)
128 writeb(dat, chip->IO_ADDR_W);
129 }
130
jz_nand_dev_ready(struct mtd_info * mtd)131 static int jz_nand_dev_ready(struct mtd_info *mtd)
132 {
133 struct jz_nand *nand = mtd_to_jz_nand(mtd);
134 return gpio_get_value_cansleep(nand->pdata->busy_gpio);
135 }
136
jz_nand_hwctl(struct mtd_info * mtd,int mode)137 static void jz_nand_hwctl(struct mtd_info *mtd, int mode)
138 {
139 struct jz_nand *nand = mtd_to_jz_nand(mtd);
140 uint32_t reg;
141
142 writel(0, nand->base + JZ_REG_NAND_IRQ_STAT);
143 reg = readl(nand->base + JZ_REG_NAND_ECC_CTRL);
144
145 reg |= JZ_NAND_ECC_CTRL_RESET;
146 reg |= JZ_NAND_ECC_CTRL_ENABLE;
147 reg |= JZ_NAND_ECC_CTRL_RS;
148
149 switch (mode) {
150 case NAND_ECC_READ:
151 reg &= ~JZ_NAND_ECC_CTRL_ENCODING;
152 nand->is_reading = true;
153 break;
154 case NAND_ECC_WRITE:
155 reg |= JZ_NAND_ECC_CTRL_ENCODING;
156 nand->is_reading = false;
157 break;
158 default:
159 break;
160 }
161
162 writel(reg, nand->base + JZ_REG_NAND_ECC_CTRL);
163 }
164
jz_nand_calculate_ecc_rs(struct mtd_info * mtd,const uint8_t * dat,uint8_t * ecc_code)165 static int jz_nand_calculate_ecc_rs(struct mtd_info *mtd, const uint8_t *dat,
166 uint8_t *ecc_code)
167 {
168 struct jz_nand *nand = mtd_to_jz_nand(mtd);
169 uint32_t reg, status;
170 int i;
171 unsigned int timeout = 1000;
172 static uint8_t empty_block_ecc[] = {0xcd, 0x9d, 0x90, 0x58, 0xf4,
173 0x8b, 0xff, 0xb7, 0x6f};
174
175 if (nand->is_reading)
176 return 0;
177
178 do {
179 status = readl(nand->base + JZ_REG_NAND_IRQ_STAT);
180 } while (!(status & JZ_NAND_STATUS_ENC_FINISH) && --timeout);
181
182 if (timeout == 0)
183 return -1;
184
185 reg = readl(nand->base + JZ_REG_NAND_ECC_CTRL);
186 reg &= ~JZ_NAND_ECC_CTRL_ENABLE;
187 writel(reg, nand->base + JZ_REG_NAND_ECC_CTRL);
188
189 for (i = 0; i < 9; ++i)
190 ecc_code[i] = readb(nand->base + JZ_REG_NAND_PAR0 + i);
191
192 /* If the written data is completly 0xff, we also want to write 0xff as
193 * ecc, otherwise we will get in trouble when doing subpage writes. */
194 if (memcmp(ecc_code, empty_block_ecc, 9) == 0)
195 memset(ecc_code, 0xff, 9);
196
197 return 0;
198 }
199
jz_nand_correct_data(uint8_t * dat,int index,int mask)200 static void jz_nand_correct_data(uint8_t *dat, int index, int mask)
201 {
202 int offset = index & 0x7;
203 uint16_t data;
204
205 index += (index >> 3);
206
207 data = dat[index];
208 data |= dat[index+1] << 8;
209
210 mask ^= (data >> offset) & 0x1ff;
211 data &= ~(0x1ff << offset);
212 data |= (mask << offset);
213
214 dat[index] = data & 0xff;
215 dat[index+1] = (data >> 8) & 0xff;
216 }
217
jz_nand_correct_ecc_rs(struct mtd_info * mtd,uint8_t * dat,uint8_t * read_ecc,uint8_t * calc_ecc)218 static int jz_nand_correct_ecc_rs(struct mtd_info *mtd, uint8_t *dat,
219 uint8_t *read_ecc, uint8_t *calc_ecc)
220 {
221 struct jz_nand *nand = mtd_to_jz_nand(mtd);
222 int i, error_count, index;
223 uint32_t reg, status, error;
224 uint32_t t;
225 unsigned int timeout = 1000;
226
227 t = read_ecc[0];
228
229 if (t == 0xff) {
230 for (i = 1; i < 9; ++i)
231 t &= read_ecc[i];
232
233 t &= dat[0];
234 t &= dat[nand->chip.ecc.size / 2];
235 t &= dat[nand->chip.ecc.size - 1];
236
237 if (t == 0xff) {
238 for (i = 1; i < nand->chip.ecc.size - 1; ++i)
239 t &= dat[i];
240 if (t == 0xff)
241 return 0;
242 }
243 }
244
245 for (i = 0; i < 9; ++i)
246 writeb(read_ecc[i], nand->base + JZ_REG_NAND_PAR0 + i);
247
248 reg = readl(nand->base + JZ_REG_NAND_ECC_CTRL);
249 reg |= JZ_NAND_ECC_CTRL_PAR_READY;
250 writel(reg, nand->base + JZ_REG_NAND_ECC_CTRL);
251
252 do {
253 status = readl(nand->base + JZ_REG_NAND_IRQ_STAT);
254 } while (!(status & JZ_NAND_STATUS_DEC_FINISH) && --timeout);
255
256 if (timeout == 0)
257 return -1;
258
259 reg = readl(nand->base + JZ_REG_NAND_ECC_CTRL);
260 reg &= ~JZ_NAND_ECC_CTRL_ENABLE;
261 writel(reg, nand->base + JZ_REG_NAND_ECC_CTRL);
262
263 if (status & JZ_NAND_STATUS_ERROR) {
264 if (status & JZ_NAND_STATUS_UNCOR_ERROR)
265 return -1;
266
267 error_count = (status & JZ_NAND_STATUS_ERR_COUNT) >> 29;
268
269 for (i = 0; i < error_count; ++i) {
270 error = readl(nand->base + JZ_REG_NAND_ERR(i));
271 index = ((error >> 16) & 0x1ff) - 1;
272 if (index >= 0 && index < 512)
273 jz_nand_correct_data(dat, index, error & 0x1ff);
274 }
275
276 return error_count;
277 }
278
279 return 0;
280 }
281
jz_nand_ioremap_resource(struct platform_device * pdev,const char * name,struct resource ** res,void * __iomem * base)282 static int jz_nand_ioremap_resource(struct platform_device *pdev,
283 const char *name, struct resource **res, void *__iomem *base)
284 {
285 int ret;
286
287 *res = platform_get_resource_byname(pdev, IORESOURCE_MEM, name);
288 if (!*res) {
289 dev_err(&pdev->dev, "Failed to get platform %s memory\n", name);
290 ret = -ENXIO;
291 goto err;
292 }
293
294 *res = request_mem_region((*res)->start, resource_size(*res),
295 pdev->name);
296 if (!*res) {
297 dev_err(&pdev->dev, "Failed to request %s memory region\n", name);
298 ret = -EBUSY;
299 goto err;
300 }
301
302 *base = ioremap((*res)->start, resource_size(*res));
303 if (!*base) {
304 dev_err(&pdev->dev, "Failed to ioremap %s memory region\n", name);
305 ret = -EBUSY;
306 goto err_release_mem;
307 }
308
309 return 0;
310
311 err_release_mem:
312 release_mem_region((*res)->start, resource_size(*res));
313 err:
314 *res = NULL;
315 *base = NULL;
316 return ret;
317 }
318
jz_nand_iounmap_resource(struct resource * res,void __iomem * base)319 static inline void jz_nand_iounmap_resource(struct resource *res,
320 void __iomem *base)
321 {
322 iounmap(base);
323 release_mem_region(res->start, resource_size(res));
324 }
325
jz_nand_detect_bank(struct platform_device * pdev,struct jz_nand * nand,unsigned char bank,size_t chipnr,uint8_t * nand_maf_id,uint8_t * nand_dev_id)326 static int jz_nand_detect_bank(struct platform_device *pdev,
327 struct jz_nand *nand, unsigned char bank,
328 size_t chipnr, uint8_t *nand_maf_id,
329 uint8_t *nand_dev_id)
330 {
331 int ret;
332 int gpio;
333 char gpio_name[9];
334 char res_name[6];
335 uint32_t ctrl;
336 struct mtd_info *mtd = &nand->mtd;
337 struct nand_chip *chip = &nand->chip;
338
339 /* Request GPIO port. */
340 gpio = JZ_GPIO_MEM_CS0 + bank - 1;
341 sprintf(gpio_name, "NAND CS%d", bank);
342 ret = gpio_request(gpio, gpio_name);
343 if (ret) {
344 dev_warn(&pdev->dev,
345 "Failed to request %s gpio %d: %d\n",
346 gpio_name, gpio, ret);
347 goto notfound_gpio;
348 }
349
350 /* Request I/O resource. */
351 sprintf(res_name, "bank%d", bank);
352 ret = jz_nand_ioremap_resource(pdev, res_name,
353 &nand->bank_mem[bank - 1],
354 &nand->bank_base[bank - 1]);
355 if (ret)
356 goto notfound_resource;
357
358 /* Enable chip in bank. */
359 jz_gpio_set_function(gpio, JZ_GPIO_FUNC_MEM_CS0);
360 ctrl = readl(nand->base + JZ_REG_NAND_CTRL);
361 ctrl |= JZ_NAND_CTRL_ENABLE_CHIP(bank - 1);
362 writel(ctrl, nand->base + JZ_REG_NAND_CTRL);
363
364 if (chipnr == 0) {
365 /* Detect first chip. */
366 ret = nand_scan_ident(mtd, 1, NULL);
367 if (ret)
368 goto notfound_id;
369
370 /* Retrieve the IDs from the first chip. */
371 chip->select_chip(mtd, 0);
372 chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1);
373 chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
374 *nand_maf_id = chip->read_byte(mtd);
375 *nand_dev_id = chip->read_byte(mtd);
376 } else {
377 /* Detect additional chip. */
378 chip->select_chip(mtd, chipnr);
379 chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1);
380 chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
381 if (*nand_maf_id != chip->read_byte(mtd)
382 || *nand_dev_id != chip->read_byte(mtd)) {
383 ret = -ENODEV;
384 goto notfound_id;
385 }
386
387 /* Update size of the MTD. */
388 chip->numchips++;
389 mtd->size += chip->chipsize;
390 }
391
392 dev_info(&pdev->dev, "Found chip %i on bank %i\n", chipnr, bank);
393 return 0;
394
395 notfound_id:
396 dev_info(&pdev->dev, "No chip found on bank %i\n", bank);
397 ctrl &= ~(JZ_NAND_CTRL_ENABLE_CHIP(bank - 1));
398 writel(ctrl, nand->base + JZ_REG_NAND_CTRL);
399 jz_gpio_set_function(gpio, JZ_GPIO_FUNC_NONE);
400 jz_nand_iounmap_resource(nand->bank_mem[bank - 1],
401 nand->bank_base[bank - 1]);
402 notfound_resource:
403 gpio_free(gpio);
404 notfound_gpio:
405 return ret;
406 }
407
jz_nand_probe(struct platform_device * pdev)408 static int jz_nand_probe(struct platform_device *pdev)
409 {
410 int ret;
411 struct jz_nand *nand;
412 struct nand_chip *chip;
413 struct mtd_info *mtd;
414 struct jz_nand_platform_data *pdata = pdev->dev.platform_data;
415 size_t chipnr, bank_idx;
416 uint8_t nand_maf_id = 0, nand_dev_id = 0;
417
418 nand = kzalloc(sizeof(*nand), GFP_KERNEL);
419 if (!nand) {
420 dev_err(&pdev->dev, "Failed to allocate device structure.\n");
421 return -ENOMEM;
422 }
423
424 ret = jz_nand_ioremap_resource(pdev, "mmio", &nand->mem, &nand->base);
425 if (ret)
426 goto err_free;
427
428 if (pdata && gpio_is_valid(pdata->busy_gpio)) {
429 ret = gpio_request(pdata->busy_gpio, "NAND busy pin");
430 if (ret) {
431 dev_err(&pdev->dev,
432 "Failed to request busy gpio %d: %d\n",
433 pdata->busy_gpio, ret);
434 goto err_iounmap_mmio;
435 }
436 }
437
438 mtd = &nand->mtd;
439 chip = &nand->chip;
440 mtd->priv = chip;
441 mtd->owner = THIS_MODULE;
442 mtd->name = "jz4740-nand";
443
444 chip->ecc.hwctl = jz_nand_hwctl;
445 chip->ecc.calculate = jz_nand_calculate_ecc_rs;
446 chip->ecc.correct = jz_nand_correct_ecc_rs;
447 chip->ecc.mode = NAND_ECC_HW_OOB_FIRST;
448 chip->ecc.size = 512;
449 chip->ecc.bytes = 9;
450 chip->ecc.strength = 4;
451
452 if (pdata)
453 chip->ecc.layout = pdata->ecc_layout;
454
455 chip->chip_delay = 50;
456 chip->cmd_ctrl = jz_nand_cmd_ctrl;
457 chip->select_chip = jz_nand_select_chip;
458
459 if (pdata && gpio_is_valid(pdata->busy_gpio))
460 chip->dev_ready = jz_nand_dev_ready;
461
462 nand->pdata = pdata;
463 platform_set_drvdata(pdev, nand);
464
465 /* We are going to autodetect NAND chips in the banks specified in the
466 * platform data. Although nand_scan_ident() can detect multiple chips,
467 * it requires those chips to be numbered consecuitively, which is not
468 * always the case for external memory banks. And a fixed chip-to-bank
469 * mapping is not practical either, since for example Dingoo units
470 * produced at different times have NAND chips in different banks.
471 */
472 chipnr = 0;
473 for (bank_idx = 0; bank_idx < JZ_NAND_NUM_BANKS; bank_idx++) {
474 unsigned char bank;
475
476 /* If there is no platform data, look for NAND in bank 1,
477 * which is the most likely bank since it is the only one
478 * that can be booted from.
479 */
480 bank = pdata ? pdata->banks[bank_idx] : bank_idx ^ 1;
481 if (bank == 0)
482 break;
483 if (bank > JZ_NAND_NUM_BANKS) {
484 dev_warn(&pdev->dev,
485 "Skipping non-existing bank: %d\n", bank);
486 continue;
487 }
488 /* The detection routine will directly or indirectly call
489 * jz_nand_select_chip(), so nand->banks has to contain the
490 * bank we're checking.
491 */
492 nand->banks[chipnr] = bank;
493 if (jz_nand_detect_bank(pdev, nand, bank, chipnr,
494 &nand_maf_id, &nand_dev_id) == 0)
495 chipnr++;
496 else
497 nand->banks[chipnr] = 0;
498 }
499 if (chipnr == 0) {
500 dev_err(&pdev->dev, "No NAND chips found\n");
501 goto err_gpio_busy;
502 }
503
504 if (pdata && pdata->ident_callback) {
505 pdata->ident_callback(pdev, chip, &pdata->partitions,
506 &pdata->num_partitions);
507 }
508
509 ret = nand_scan_tail(mtd);
510 if (ret) {
511 dev_err(&pdev->dev, "Failed to scan NAND\n");
512 goto err_unclaim_banks;
513 }
514
515 ret = mtd_device_parse_register(mtd, NULL, NULL,
516 pdata ? pdata->partitions : NULL,
517 pdata ? pdata->num_partitions : 0);
518
519 if (ret) {
520 dev_err(&pdev->dev, "Failed to add mtd device\n");
521 goto err_nand_release;
522 }
523
524 dev_info(&pdev->dev, "Successfully registered JZ4740 NAND driver\n");
525
526 return 0;
527
528 err_nand_release:
529 nand_release(mtd);
530 err_unclaim_banks:
531 while (chipnr--) {
532 unsigned char bank = nand->banks[chipnr];
533 gpio_free(JZ_GPIO_MEM_CS0 + bank - 1);
534 jz_nand_iounmap_resource(nand->bank_mem[bank - 1],
535 nand->bank_base[bank - 1]);
536 }
537 writel(0, nand->base + JZ_REG_NAND_CTRL);
538 err_gpio_busy:
539 if (pdata && gpio_is_valid(pdata->busy_gpio))
540 gpio_free(pdata->busy_gpio);
541 platform_set_drvdata(pdev, NULL);
542 err_iounmap_mmio:
543 jz_nand_iounmap_resource(nand->mem, nand->base);
544 err_free:
545 kfree(nand);
546 return ret;
547 }
548
jz_nand_remove(struct platform_device * pdev)549 static int jz_nand_remove(struct platform_device *pdev)
550 {
551 struct jz_nand *nand = platform_get_drvdata(pdev);
552 struct jz_nand_platform_data *pdata = pdev->dev.platform_data;
553 size_t i;
554
555 nand_release(&nand->mtd);
556
557 /* Deassert and disable all chips */
558 writel(0, nand->base + JZ_REG_NAND_CTRL);
559
560 for (i = 0; i < JZ_NAND_NUM_BANKS; ++i) {
561 unsigned char bank = nand->banks[i];
562 if (bank != 0) {
563 jz_nand_iounmap_resource(nand->bank_mem[bank - 1],
564 nand->bank_base[bank - 1]);
565 gpio_free(JZ_GPIO_MEM_CS0 + bank - 1);
566 }
567 }
568 if (pdata && gpio_is_valid(pdata->busy_gpio))
569 gpio_free(pdata->busy_gpio);
570
571 jz_nand_iounmap_resource(nand->mem, nand->base);
572
573 platform_set_drvdata(pdev, NULL);
574 kfree(nand);
575
576 return 0;
577 }
578
579 static struct platform_driver jz_nand_driver = {
580 .probe = jz_nand_probe,
581 .remove = jz_nand_remove,
582 .driver = {
583 .name = "jz4740-nand",
584 .owner = THIS_MODULE,
585 },
586 };
587
588 module_platform_driver(jz_nand_driver);
589
590 MODULE_LICENSE("GPL");
591 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
592 MODULE_DESCRIPTION("NAND controller driver for JZ4740 SoC");
593 MODULE_ALIAS("platform:jz4740-nand");
594