1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Ingenic JZ47xx NAND driver
4  *
5  * Copyright (c) 2015 Imagination Technologies
6  * Author: Alex Smith <alex.smith@imgtec.com>
7  */
8 
9 #include <linux/delay.h>
10 #include <linux/init.h>
11 #include <linux/io.h>
12 #include <linux/list.h>
13 #include <linux/module.h>
14 #include <linux/of.h>
15 #include <linux/of_address.h>
16 #include <linux/of_device.h>
17 #include <linux/gpio/consumer.h>
18 #include <linux/platform_device.h>
19 #include <linux/slab.h>
20 #include <linux/mtd/mtd.h>
21 #include <linux/mtd/rawnand.h>
22 #include <linux/mtd/partitions.h>
23 
24 #include <linux/jz4780-nemc.h>
25 
26 #include "ingenic_ecc.h"
27 
28 #define DRV_NAME	"ingenic-nand"
29 
30 struct jz_soc_info {
31 	unsigned long data_offset;
32 	unsigned long addr_offset;
33 	unsigned long cmd_offset;
34 	const struct mtd_ooblayout_ops *oob_layout;
35 	bool oob_first;
36 };
37 
38 struct ingenic_nand_cs {
39 	unsigned int bank;
40 	void __iomem *base;
41 };
42 
43 struct ingenic_nfc {
44 	struct device *dev;
45 	struct ingenic_ecc *ecc;
46 	const struct jz_soc_info *soc_info;
47 	struct nand_controller controller;
48 	unsigned int num_banks;
49 	struct list_head chips;
50 	struct ingenic_nand_cs cs[];
51 };
52 
53 struct ingenic_nand {
54 	struct nand_chip chip;
55 	struct list_head chip_list;
56 
57 	struct gpio_desc *busy_gpio;
58 	struct gpio_desc *wp_gpio;
59 	unsigned int reading: 1;
60 };
61 
62 static inline struct ingenic_nand *to_ingenic_nand(struct mtd_info *mtd)
63 {
64 	return container_of(mtd_to_nand(mtd), struct ingenic_nand, chip);
65 }
66 
67 static inline struct ingenic_nfc *to_ingenic_nfc(struct nand_controller *ctrl)
68 {
69 	return container_of(ctrl, struct ingenic_nfc, controller);
70 }
71 
72 static int qi_lb60_ooblayout_ecc(struct mtd_info *mtd, int section,
73 				 struct mtd_oob_region *oobregion)
74 {
75 	struct nand_chip *chip = mtd_to_nand(mtd);
76 	struct nand_ecc_ctrl *ecc = &chip->ecc;
77 
78 	if (section || !ecc->total)
79 		return -ERANGE;
80 
81 	oobregion->length = ecc->total;
82 	oobregion->offset = 12;
83 
84 	return 0;
85 }
86 
87 static int qi_lb60_ooblayout_free(struct mtd_info *mtd, int section,
88 				  struct mtd_oob_region *oobregion)
89 {
90 	struct nand_chip *chip = mtd_to_nand(mtd);
91 	struct nand_ecc_ctrl *ecc = &chip->ecc;
92 
93 	if (section)
94 		return -ERANGE;
95 
96 	oobregion->length = mtd->oobsize - ecc->total - 12;
97 	oobregion->offset = 12 + ecc->total;
98 
99 	return 0;
100 }
101 
102 static const struct mtd_ooblayout_ops qi_lb60_ooblayout_ops = {
103 	.ecc = qi_lb60_ooblayout_ecc,
104 	.free = qi_lb60_ooblayout_free,
105 };
106 
107 static int jz4725b_ooblayout_ecc(struct mtd_info *mtd, int section,
108 				 struct mtd_oob_region *oobregion)
109 {
110 	struct nand_chip *chip = mtd_to_nand(mtd);
111 	struct nand_ecc_ctrl *ecc = &chip->ecc;
112 
113 	if (section || !ecc->total)
114 		return -ERANGE;
115 
116 	oobregion->length = ecc->total;
117 	oobregion->offset = 3;
118 
119 	return 0;
120 }
121 
122 static int jz4725b_ooblayout_free(struct mtd_info *mtd, int section,
123 				  struct mtd_oob_region *oobregion)
124 {
125 	struct nand_chip *chip = mtd_to_nand(mtd);
126 	struct nand_ecc_ctrl *ecc = &chip->ecc;
127 
128 	if (section)
129 		return -ERANGE;
130 
131 	oobregion->length = mtd->oobsize - ecc->total - 3;
132 	oobregion->offset = 3 + ecc->total;
133 
134 	return 0;
135 }
136 
137 static const struct mtd_ooblayout_ops jz4725b_ooblayout_ops = {
138 	.ecc = jz4725b_ooblayout_ecc,
139 	.free = jz4725b_ooblayout_free,
140 };
141 
142 static void ingenic_nand_ecc_hwctl(struct nand_chip *chip, int mode)
143 {
144 	struct ingenic_nand *nand = to_ingenic_nand(nand_to_mtd(chip));
145 
146 	nand->reading = (mode == NAND_ECC_READ);
147 }
148 
149 static int ingenic_nand_ecc_calculate(struct nand_chip *chip, const u8 *dat,
150 				      u8 *ecc_code)
151 {
152 	struct ingenic_nand *nand = to_ingenic_nand(nand_to_mtd(chip));
153 	struct ingenic_nfc *nfc = to_ingenic_nfc(nand->chip.controller);
154 	struct ingenic_ecc_params params;
155 
156 	/*
157 	 * Don't need to generate the ECC when reading, the ECC engine does it
158 	 * for us as part of decoding/correction.
159 	 */
160 	if (nand->reading)
161 		return 0;
162 
163 	params.size = nand->chip.ecc.size;
164 	params.bytes = nand->chip.ecc.bytes;
165 	params.strength = nand->chip.ecc.strength;
166 
167 	return ingenic_ecc_calculate(nfc->ecc, &params, dat, ecc_code);
168 }
169 
170 static int ingenic_nand_ecc_correct(struct nand_chip *chip, u8 *dat,
171 				    u8 *read_ecc, u8 *calc_ecc)
172 {
173 	struct ingenic_nand *nand = to_ingenic_nand(nand_to_mtd(chip));
174 	struct ingenic_nfc *nfc = to_ingenic_nfc(nand->chip.controller);
175 	struct ingenic_ecc_params params;
176 
177 	params.size = nand->chip.ecc.size;
178 	params.bytes = nand->chip.ecc.bytes;
179 	params.strength = nand->chip.ecc.strength;
180 
181 	return ingenic_ecc_correct(nfc->ecc, &params, dat, read_ecc);
182 }
183 
184 static int ingenic_nand_attach_chip(struct nand_chip *chip)
185 {
186 	struct mtd_info *mtd = nand_to_mtd(chip);
187 	struct ingenic_nfc *nfc = to_ingenic_nfc(chip->controller);
188 	int eccbytes;
189 
190 	if (chip->ecc.strength == 4) {
191 		/* JZ4740 uses 9 bytes of ECC to correct maximum 4 errors */
192 		chip->ecc.bytes = 9;
193 	} else {
194 		chip->ecc.bytes = fls((1 + 8) * chip->ecc.size)	*
195 				  (chip->ecc.strength / 8);
196 	}
197 
198 	switch (chip->ecc.engine_type) {
199 	case NAND_ECC_ENGINE_TYPE_ON_HOST:
200 		if (!nfc->ecc) {
201 			dev_err(nfc->dev, "HW ECC selected, but ECC controller not found\n");
202 			return -ENODEV;
203 		}
204 
205 		chip->ecc.hwctl = ingenic_nand_ecc_hwctl;
206 		chip->ecc.calculate = ingenic_nand_ecc_calculate;
207 		chip->ecc.correct = ingenic_nand_ecc_correct;
208 		fallthrough;
209 	case NAND_ECC_ENGINE_TYPE_SOFT:
210 		dev_info(nfc->dev, "using %s (strength %d, size %d, bytes %d)\n",
211 			 (nfc->ecc) ? "hardware ECC" : "software ECC",
212 			 chip->ecc.strength, chip->ecc.size, chip->ecc.bytes);
213 		break;
214 	case NAND_ECC_ENGINE_TYPE_NONE:
215 		dev_info(nfc->dev, "not using ECC\n");
216 		break;
217 	default:
218 		dev_err(nfc->dev, "ECC mode %d not supported\n",
219 			chip->ecc.engine_type);
220 		return -EINVAL;
221 	}
222 
223 	/* The NAND core will generate the ECC layout for SW ECC */
224 	if (chip->ecc.engine_type != NAND_ECC_ENGINE_TYPE_ON_HOST)
225 		return 0;
226 
227 	/* Generate ECC layout. ECC codes are right aligned in the OOB area. */
228 	eccbytes = mtd->writesize / chip->ecc.size * chip->ecc.bytes;
229 
230 	if (eccbytes > mtd->oobsize - 2) {
231 		dev_err(nfc->dev,
232 			"invalid ECC config: required %d ECC bytes, but only %d are available",
233 			eccbytes, mtd->oobsize - 2);
234 		return -EINVAL;
235 	}
236 
237 	/*
238 	 * The generic layout for BBT markers will most likely overlap with our
239 	 * ECC bytes in the OOB, so move the BBT markers outside the OOB area.
240 	 */
241 	if (chip->bbt_options & NAND_BBT_USE_FLASH)
242 		chip->bbt_options |= NAND_BBT_NO_OOB;
243 
244 	if (nfc->soc_info->oob_first)
245 		chip->ecc.read_page = nand_read_page_hwecc_oob_first;
246 
247 	/* For legacy reasons we use a different layout on the qi,lb60 board. */
248 	if (of_machine_is_compatible("qi,lb60"))
249 		mtd_set_ooblayout(mtd, &qi_lb60_ooblayout_ops);
250 	else if (nfc->soc_info->oob_layout)
251 		mtd_set_ooblayout(mtd, nfc->soc_info->oob_layout);
252 	else
253 		mtd_set_ooblayout(mtd, nand_get_large_page_ooblayout());
254 
255 	return 0;
256 }
257 
258 static int ingenic_nand_exec_instr(struct nand_chip *chip,
259 				   struct ingenic_nand_cs *cs,
260 				   const struct nand_op_instr *instr)
261 {
262 	struct ingenic_nand *nand = to_ingenic_nand(nand_to_mtd(chip));
263 	struct ingenic_nfc *nfc = to_ingenic_nfc(chip->controller);
264 	unsigned int i;
265 
266 	switch (instr->type) {
267 	case NAND_OP_CMD_INSTR:
268 		writeb(instr->ctx.cmd.opcode,
269 		       cs->base + nfc->soc_info->cmd_offset);
270 		return 0;
271 	case NAND_OP_ADDR_INSTR:
272 		for (i = 0; i < instr->ctx.addr.naddrs; i++)
273 			writeb(instr->ctx.addr.addrs[i],
274 			       cs->base + nfc->soc_info->addr_offset);
275 		return 0;
276 	case NAND_OP_DATA_IN_INSTR:
277 		if (instr->ctx.data.force_8bit ||
278 		    !(chip->options & NAND_BUSWIDTH_16))
279 			ioread8_rep(cs->base + nfc->soc_info->data_offset,
280 				    instr->ctx.data.buf.in,
281 				    instr->ctx.data.len);
282 		else
283 			ioread16_rep(cs->base + nfc->soc_info->data_offset,
284 				     instr->ctx.data.buf.in,
285 				     instr->ctx.data.len);
286 		return 0;
287 	case NAND_OP_DATA_OUT_INSTR:
288 		if (instr->ctx.data.force_8bit ||
289 		    !(chip->options & NAND_BUSWIDTH_16))
290 			iowrite8_rep(cs->base + nfc->soc_info->data_offset,
291 				     instr->ctx.data.buf.out,
292 				     instr->ctx.data.len);
293 		else
294 			iowrite16_rep(cs->base + nfc->soc_info->data_offset,
295 				      instr->ctx.data.buf.out,
296 				      instr->ctx.data.len);
297 		return 0;
298 	case NAND_OP_WAITRDY_INSTR:
299 		if (!nand->busy_gpio)
300 			return nand_soft_waitrdy(chip,
301 						 instr->ctx.waitrdy.timeout_ms);
302 
303 		return nand_gpio_waitrdy(chip, nand->busy_gpio,
304 					 instr->ctx.waitrdy.timeout_ms);
305 	default:
306 		break;
307 	}
308 
309 	return -EINVAL;
310 }
311 
312 static int ingenic_nand_exec_op(struct nand_chip *chip,
313 				const struct nand_operation *op,
314 				bool check_only)
315 {
316 	struct ingenic_nand *nand = to_ingenic_nand(nand_to_mtd(chip));
317 	struct ingenic_nfc *nfc = to_ingenic_nfc(nand->chip.controller);
318 	struct ingenic_nand_cs *cs;
319 	unsigned int i;
320 	int ret = 0;
321 
322 	if (check_only)
323 		return 0;
324 
325 	cs = &nfc->cs[op->cs];
326 	jz4780_nemc_assert(nfc->dev, cs->bank, true);
327 	for (i = 0; i < op->ninstrs; i++) {
328 		ret = ingenic_nand_exec_instr(chip, cs, &op->instrs[i]);
329 		if (ret)
330 			break;
331 
332 		if (op->instrs[i].delay_ns)
333 			ndelay(op->instrs[i].delay_ns);
334 	}
335 	jz4780_nemc_assert(nfc->dev, cs->bank, false);
336 
337 	return ret;
338 }
339 
340 static const struct nand_controller_ops ingenic_nand_controller_ops = {
341 	.attach_chip = ingenic_nand_attach_chip,
342 	.exec_op = ingenic_nand_exec_op,
343 };
344 
345 static int ingenic_nand_init_chip(struct platform_device *pdev,
346 				  struct ingenic_nfc *nfc,
347 				  struct device_node *np,
348 				  unsigned int chipnr)
349 {
350 	struct device *dev = &pdev->dev;
351 	struct ingenic_nand *nand;
352 	struct ingenic_nand_cs *cs;
353 	struct nand_chip *chip;
354 	struct mtd_info *mtd;
355 	const __be32 *reg;
356 	int ret = 0;
357 
358 	cs = &nfc->cs[chipnr];
359 
360 	reg = of_get_property(np, "reg", NULL);
361 	if (!reg)
362 		return -EINVAL;
363 
364 	cs->bank = be32_to_cpu(*reg);
365 
366 	jz4780_nemc_set_type(nfc->dev, cs->bank, JZ4780_NEMC_BANK_NAND);
367 
368 	cs->base = devm_platform_ioremap_resource(pdev, chipnr);
369 	if (IS_ERR(cs->base))
370 		return PTR_ERR(cs->base);
371 
372 	nand = devm_kzalloc(dev, sizeof(*nand), GFP_KERNEL);
373 	if (!nand)
374 		return -ENOMEM;
375 
376 	nand->busy_gpio = devm_gpiod_get_optional(dev, "rb", GPIOD_IN);
377 
378 	if (IS_ERR(nand->busy_gpio)) {
379 		ret = PTR_ERR(nand->busy_gpio);
380 		dev_err(dev, "failed to request busy GPIO: %d\n", ret);
381 		return ret;
382 	}
383 
384 	/*
385 	 * The rb-gpios semantics was undocumented and qi,lb60 (along with
386 	 * the ingenic driver) got it wrong. The active state encodes the
387 	 * NAND ready state, which is high level. Since there's no signal
388 	 * inverter on this board, it should be active-high. Let's fix that
389 	 * here for older DTs so we can re-use the generic nand_gpio_waitrdy()
390 	 * helper, and be consistent with what other drivers do.
391 	 */
392 	if (of_machine_is_compatible("qi,lb60") &&
393 	    gpiod_is_active_low(nand->busy_gpio))
394 		gpiod_toggle_active_low(nand->busy_gpio);
395 
396 	nand->wp_gpio = devm_gpiod_get_optional(dev, "wp", GPIOD_OUT_LOW);
397 
398 	if (IS_ERR(nand->wp_gpio)) {
399 		ret = PTR_ERR(nand->wp_gpio);
400 		dev_err(dev, "failed to request WP GPIO: %d\n", ret);
401 		return ret;
402 	}
403 
404 	chip = &nand->chip;
405 	mtd = nand_to_mtd(chip);
406 	mtd->name = devm_kasprintf(dev, GFP_KERNEL, "%s.%d", dev_name(dev),
407 				   cs->bank);
408 	if (!mtd->name)
409 		return -ENOMEM;
410 	mtd->dev.parent = dev;
411 
412 	chip->options = NAND_NO_SUBPAGE_WRITE;
413 	chip->ecc.engine_type = NAND_ECC_ENGINE_TYPE_ON_HOST;
414 	chip->controller = &nfc->controller;
415 	nand_set_flash_node(chip, np);
416 
417 	chip->controller->ops = &ingenic_nand_controller_ops;
418 	ret = nand_scan(chip, 1);
419 	if (ret)
420 		return ret;
421 
422 	ret = mtd_device_register(mtd, NULL, 0);
423 	if (ret) {
424 		nand_cleanup(chip);
425 		return ret;
426 	}
427 
428 	list_add_tail(&nand->chip_list, &nfc->chips);
429 
430 	return 0;
431 }
432 
433 static void ingenic_nand_cleanup_chips(struct ingenic_nfc *nfc)
434 {
435 	struct ingenic_nand *ingenic_chip;
436 	struct nand_chip *chip;
437 	int ret;
438 
439 	while (!list_empty(&nfc->chips)) {
440 		ingenic_chip = list_first_entry(&nfc->chips,
441 						struct ingenic_nand, chip_list);
442 		chip = &ingenic_chip->chip;
443 		ret = mtd_device_unregister(nand_to_mtd(chip));
444 		WARN_ON(ret);
445 		nand_cleanup(chip);
446 		list_del(&ingenic_chip->chip_list);
447 	}
448 }
449 
450 static int ingenic_nand_init_chips(struct ingenic_nfc *nfc,
451 				   struct platform_device *pdev)
452 {
453 	struct device *dev = &pdev->dev;
454 	struct device_node *np;
455 	int i = 0;
456 	int ret;
457 	int num_chips = of_get_child_count(dev->of_node);
458 
459 	if (num_chips > nfc->num_banks) {
460 		dev_err(dev, "found %d chips but only %d banks\n",
461 			num_chips, nfc->num_banks);
462 		return -EINVAL;
463 	}
464 
465 	for_each_child_of_node(dev->of_node, np) {
466 		ret = ingenic_nand_init_chip(pdev, nfc, np, i);
467 		if (ret) {
468 			ingenic_nand_cleanup_chips(nfc);
469 			of_node_put(np);
470 			return ret;
471 		}
472 
473 		i++;
474 	}
475 
476 	return 0;
477 }
478 
479 static int ingenic_nand_probe(struct platform_device *pdev)
480 {
481 	struct device *dev = &pdev->dev;
482 	unsigned int num_banks;
483 	struct ingenic_nfc *nfc;
484 	int ret;
485 
486 	num_banks = jz4780_nemc_num_banks(dev);
487 	if (num_banks == 0) {
488 		dev_err(dev, "no banks found\n");
489 		return -ENODEV;
490 	}
491 
492 	nfc = devm_kzalloc(dev, struct_size(nfc, cs, num_banks), GFP_KERNEL);
493 	if (!nfc)
494 		return -ENOMEM;
495 
496 	nfc->soc_info = device_get_match_data(dev);
497 	if (!nfc->soc_info)
498 		return -EINVAL;
499 
500 	/*
501 	 * Check for ECC HW before we call nand_scan_ident, to prevent us from
502 	 * having to call it again if the ECC driver returns -EPROBE_DEFER.
503 	 */
504 	nfc->ecc = of_ingenic_ecc_get(dev->of_node);
505 	if (IS_ERR(nfc->ecc))
506 		return PTR_ERR(nfc->ecc);
507 
508 	nfc->dev = dev;
509 	nfc->num_banks = num_banks;
510 
511 	nand_controller_init(&nfc->controller);
512 	INIT_LIST_HEAD(&nfc->chips);
513 
514 	ret = ingenic_nand_init_chips(nfc, pdev);
515 	if (ret) {
516 		if (nfc->ecc)
517 			ingenic_ecc_release(nfc->ecc);
518 		return ret;
519 	}
520 
521 	platform_set_drvdata(pdev, nfc);
522 	return 0;
523 }
524 
525 static int ingenic_nand_remove(struct platform_device *pdev)
526 {
527 	struct ingenic_nfc *nfc = platform_get_drvdata(pdev);
528 
529 	if (nfc->ecc)
530 		ingenic_ecc_release(nfc->ecc);
531 
532 	ingenic_nand_cleanup_chips(nfc);
533 
534 	return 0;
535 }
536 
537 static const struct jz_soc_info jz4740_soc_info = {
538 	.data_offset = 0x00000000,
539 	.cmd_offset = 0x00008000,
540 	.addr_offset = 0x00010000,
541 	.oob_first = true,
542 };
543 
544 static const struct jz_soc_info jz4725b_soc_info = {
545 	.data_offset = 0x00000000,
546 	.cmd_offset = 0x00008000,
547 	.addr_offset = 0x00010000,
548 	.oob_layout = &jz4725b_ooblayout_ops,
549 };
550 
551 static const struct jz_soc_info jz4780_soc_info = {
552 	.data_offset = 0x00000000,
553 	.cmd_offset = 0x00400000,
554 	.addr_offset = 0x00800000,
555 };
556 
557 static const struct of_device_id ingenic_nand_dt_match[] = {
558 	{ .compatible = "ingenic,jz4740-nand", .data = &jz4740_soc_info },
559 	{ .compatible = "ingenic,jz4725b-nand", .data = &jz4725b_soc_info },
560 	{ .compatible = "ingenic,jz4780-nand", .data = &jz4780_soc_info },
561 	{},
562 };
563 MODULE_DEVICE_TABLE(of, ingenic_nand_dt_match);
564 
565 static struct platform_driver ingenic_nand_driver = {
566 	.probe		= ingenic_nand_probe,
567 	.remove		= ingenic_nand_remove,
568 	.driver	= {
569 		.name	= DRV_NAME,
570 		.of_match_table = ingenic_nand_dt_match,
571 	},
572 };
573 module_platform_driver(ingenic_nand_driver);
574 
575 MODULE_AUTHOR("Alex Smith <alex@alex-smith.me.uk>");
576 MODULE_AUTHOR("Harvey Hunt <harveyhuntnexus@gmail.com>");
577 MODULE_DESCRIPTION("Ingenic JZ47xx NAND driver");
578 MODULE_LICENSE("GPL v2");
579