1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright �� 2004-2008 Simtec Electronics
4 *	http://armlinux.simtec.co.uk/
5 *	Ben Dooks <ben@simtec.co.uk>
6 *
7 * Samsung S3C2410/S3C2440/S3C2412 NAND driver
8*/
9
10#define pr_fmt(fmt) "nand-s3c2410: " fmt
11
12#ifdef CONFIG_MTD_NAND_S3C2410_DEBUG
13#define DEBUG
14#endif
15
16#include <linux/module.h>
17#include <linux/types.h>
18#include <linux/kernel.h>
19#include <linux/string.h>
20#include <linux/io.h>
21#include <linux/ioport.h>
22#include <linux/platform_device.h>
23#include <linux/delay.h>
24#include <linux/err.h>
25#include <linux/slab.h>
26#include <linux/clk.h>
27#include <linux/cpufreq.h>
28#include <linux/of.h>
29
30#include <linux/mtd/mtd.h>
31#include <linux/mtd/rawnand.h>
32#include <linux/mtd/partitions.h>
33
34#include <linux/platform_data/mtd-nand-s3c2410.h>
35
36#define S3C2410_NFREG(x) (x)
37
38#define S3C2410_NFCONF		S3C2410_NFREG(0x00)
39#define S3C2410_NFCMD		S3C2410_NFREG(0x04)
40#define S3C2410_NFADDR		S3C2410_NFREG(0x08)
41#define S3C2410_NFDATA		S3C2410_NFREG(0x0C)
42#define S3C2410_NFSTAT		S3C2410_NFREG(0x10)
43#define S3C2410_NFECC		S3C2410_NFREG(0x14)
44#define S3C2440_NFCONT		S3C2410_NFREG(0x04)
45#define S3C2440_NFCMD		S3C2410_NFREG(0x08)
46#define S3C2440_NFADDR		S3C2410_NFREG(0x0C)
47#define S3C2440_NFDATA		S3C2410_NFREG(0x10)
48#define S3C2440_NFSTAT		S3C2410_NFREG(0x20)
49#define S3C2440_NFMECC0		S3C2410_NFREG(0x2C)
50#define S3C2412_NFSTAT		S3C2410_NFREG(0x28)
51#define S3C2412_NFMECC0		S3C2410_NFREG(0x34)
52#define S3C2410_NFCONF_EN		(1<<15)
53#define S3C2410_NFCONF_INITECC		(1<<12)
54#define S3C2410_NFCONF_nFCE		(1<<11)
55#define S3C2410_NFCONF_TACLS(x)		((x)<<8)
56#define S3C2410_NFCONF_TWRPH0(x)	((x)<<4)
57#define S3C2410_NFCONF_TWRPH1(x)	((x)<<0)
58#define S3C2410_NFSTAT_BUSY		(1<<0)
59#define S3C2440_NFCONF_TACLS(x)		((x)<<12)
60#define S3C2440_NFCONF_TWRPH0(x)	((x)<<8)
61#define S3C2440_NFCONF_TWRPH1(x)	((x)<<4)
62#define S3C2440_NFCONT_INITECC		(1<<4)
63#define S3C2440_NFCONT_nFCE		(1<<1)
64#define S3C2440_NFCONT_ENABLE		(1<<0)
65#define S3C2440_NFSTAT_READY		(1<<0)
66#define S3C2412_NFCONF_NANDBOOT		(1<<31)
67#define S3C2412_NFCONT_INIT_MAIN_ECC	(1<<5)
68#define S3C2412_NFCONT_nFCE0		(1<<1)
69#define S3C2412_NFSTAT_READY		(1<<0)
70
71/* new oob placement block for use with hardware ecc generation
72 */
73static int s3c2410_ooblayout_ecc(struct mtd_info *mtd, int section,
74				 struct mtd_oob_region *oobregion)
75{
76	if (section)
77		return -ERANGE;
78
79	oobregion->offset = 0;
80	oobregion->length = 3;
81
82	return 0;
83}
84
85static int s3c2410_ooblayout_free(struct mtd_info *mtd, int section,
86				  struct mtd_oob_region *oobregion)
87{
88	if (section)
89		return -ERANGE;
90
91	oobregion->offset = 8;
92	oobregion->length = 8;
93
94	return 0;
95}
96
97static const struct mtd_ooblayout_ops s3c2410_ooblayout_ops = {
98	.ecc = s3c2410_ooblayout_ecc,
99	.free = s3c2410_ooblayout_free,
100};
101
102/* controller and mtd information */
103
104struct s3c2410_nand_info;
105
106/**
107 * struct s3c2410_nand_mtd - driver MTD structure
108 * @chip: The NAND chip information.
109 * @set: The platform information supplied for this set of NAND chips.
110 * @info: Link back to the hardware information.
111*/
112struct s3c2410_nand_mtd {
113	struct nand_chip		chip;
114	struct s3c2410_nand_set		*set;
115	struct s3c2410_nand_info	*info;
116};
117
118enum s3c_cpu_type {
119	TYPE_S3C2410,
120	TYPE_S3C2412,
121	TYPE_S3C2440,
122};
123
124enum s3c_nand_clk_state {
125	CLOCK_DISABLE	= 0,
126	CLOCK_ENABLE,
127	CLOCK_SUSPEND,
128};
129
130/* overview of the s3c2410 nand state */
131
132/**
133 * struct s3c2410_nand_info - NAND controller state.
134 * @controller: Base controller structure.
135 * @mtds: An array of MTD instances on this controller.
136 * @platform: The platform data for this board.
137 * @device: The platform device we bound to.
138 * @clk: The clock resource for this controller.
139 * @regs: The area mapped for the hardware registers.
140 * @sel_reg: Pointer to the register controlling the NAND selection.
141 * @sel_bit: The bit in @sel_reg to select the NAND chip.
142 * @mtd_count: The number of MTDs created from this controller.
143 * @save_sel: The contents of @sel_reg to be saved over suspend.
144 * @clk_rate: The clock rate from @clk.
145 * @clk_state: The current clock state.
146 * @cpu_type: The exact type of this controller.
147 */
148struct s3c2410_nand_info {
149	/* mtd info */
150	struct nand_controller		controller;
151	struct s3c2410_nand_mtd		*mtds;
152	struct s3c2410_platform_nand	*platform;
153
154	/* device info */
155	struct device			*device;
156	struct clk			*clk;
157	void __iomem			*regs;
158	void __iomem			*sel_reg;
159	int				sel_bit;
160	int				mtd_count;
161	unsigned long			save_sel;
162	unsigned long			clk_rate;
163	enum s3c_nand_clk_state		clk_state;
164
165	enum s3c_cpu_type		cpu_type;
166};
167
168struct s3c24XX_nand_devtype_data {
169	enum s3c_cpu_type type;
170};
171
172static const struct s3c24XX_nand_devtype_data s3c2410_nand_devtype_data = {
173	.type = TYPE_S3C2410,
174};
175
176static const struct s3c24XX_nand_devtype_data s3c2412_nand_devtype_data = {
177	.type = TYPE_S3C2412,
178};
179
180static const struct s3c24XX_nand_devtype_data s3c2440_nand_devtype_data = {
181	.type = TYPE_S3C2440,
182};
183
184/* conversion functions */
185
186static struct s3c2410_nand_mtd *s3c2410_nand_mtd_toours(struct mtd_info *mtd)
187{
188	return container_of(mtd_to_nand(mtd), struct s3c2410_nand_mtd,
189			    chip);
190}
191
192static struct s3c2410_nand_info *s3c2410_nand_mtd_toinfo(struct mtd_info *mtd)
193{
194	return s3c2410_nand_mtd_toours(mtd)->info;
195}
196
197static struct s3c2410_nand_info *to_nand_info(struct platform_device *dev)
198{
199	return platform_get_drvdata(dev);
200}
201
202static struct s3c2410_platform_nand *to_nand_plat(struct platform_device *dev)
203{
204	return dev_get_platdata(&dev->dev);
205}
206
207static inline int allow_clk_suspend(struct s3c2410_nand_info *info)
208{
209#ifdef CONFIG_MTD_NAND_S3C2410_CLKSTOP
210	return 1;
211#else
212	return 0;
213#endif
214}
215
216/**
217 * s3c2410_nand_clk_set_state - Enable, disable or suspend NAND clock.
218 * @info: The controller instance.
219 * @new_state: State to which clock should be set.
220 */
221static void s3c2410_nand_clk_set_state(struct s3c2410_nand_info *info,
222		enum s3c_nand_clk_state new_state)
223{
224	if (!allow_clk_suspend(info) && new_state == CLOCK_SUSPEND)
225		return;
226
227	if (info->clk_state == CLOCK_ENABLE) {
228		if (new_state != CLOCK_ENABLE)
229			clk_disable_unprepare(info->clk);
230	} else {
231		if (new_state == CLOCK_ENABLE)
232			clk_prepare_enable(info->clk);
233	}
234
235	info->clk_state = new_state;
236}
237
238/* timing calculations */
239
240#define NS_IN_KHZ 1000000
241
242/**
243 * s3c_nand_calc_rate - calculate timing data.
244 * @wanted: The cycle time in nanoseconds.
245 * @clk: The clock rate in kHz.
246 * @max: The maximum divider value.
247 *
248 * Calculate the timing value from the given parameters.
249 */
250static int s3c_nand_calc_rate(int wanted, unsigned long clk, int max)
251{
252	int result;
253
254	result = DIV_ROUND_UP((wanted * clk), NS_IN_KHZ);
255
256	pr_debug("result %d from %ld, %d\n", result, clk, wanted);
257
258	if (result > max) {
259		pr_err("%d ns is too big for current clock rate %ld\n",
260			wanted, clk);
261		return -1;
262	}
263
264	if (result < 1)
265		result = 1;
266
267	return result;
268}
269
270#define to_ns(ticks, clk) (((ticks) * NS_IN_KHZ) / (unsigned int)(clk))
271
272/* controller setup */
273
274/**
275 * s3c2410_nand_setrate - setup controller timing information.
276 * @info: The controller instance.
277 *
278 * Given the information supplied by the platform, calculate and set
279 * the necessary timing registers in the hardware to generate the
280 * necessary timing cycles to the hardware.
281 */
282static int s3c2410_nand_setrate(struct s3c2410_nand_info *info)
283{
284	struct s3c2410_platform_nand *plat = info->platform;
285	int tacls_max = (info->cpu_type == TYPE_S3C2412) ? 8 : 4;
286	int tacls, twrph0, twrph1;
287	unsigned long clkrate = clk_get_rate(info->clk);
288	unsigned long set, cfg, mask;
289	unsigned long flags;
290
291	/* calculate the timing information for the controller */
292
293	info->clk_rate = clkrate;
294	clkrate /= 1000;	/* turn clock into kHz for ease of use */
295
296	if (plat != NULL) {
297		tacls = s3c_nand_calc_rate(plat->tacls, clkrate, tacls_max);
298		twrph0 = s3c_nand_calc_rate(plat->twrph0, clkrate, 8);
299		twrph1 = s3c_nand_calc_rate(plat->twrph1, clkrate, 8);
300	} else {
301		/* default timings */
302		tacls = tacls_max;
303		twrph0 = 8;
304		twrph1 = 8;
305	}
306
307	if (tacls < 0 || twrph0 < 0 || twrph1 < 0) {
308		dev_err(info->device, "cannot get suitable timings\n");
309		return -EINVAL;
310	}
311
312	dev_info(info->device, "Tacls=%d, %dns Twrph0=%d %dns, Twrph1=%d %dns\n",
313		tacls, to_ns(tacls, clkrate), twrph0, to_ns(twrph0, clkrate),
314						twrph1, to_ns(twrph1, clkrate));
315
316	switch (info->cpu_type) {
317	case TYPE_S3C2410:
318		mask = (S3C2410_NFCONF_TACLS(3) |
319			S3C2410_NFCONF_TWRPH0(7) |
320			S3C2410_NFCONF_TWRPH1(7));
321		set = S3C2410_NFCONF_EN;
322		set |= S3C2410_NFCONF_TACLS(tacls - 1);
323		set |= S3C2410_NFCONF_TWRPH0(twrph0 - 1);
324		set |= S3C2410_NFCONF_TWRPH1(twrph1 - 1);
325		break;
326
327	case TYPE_S3C2440:
328	case TYPE_S3C2412:
329		mask = (S3C2440_NFCONF_TACLS(tacls_max - 1) |
330			S3C2440_NFCONF_TWRPH0(7) |
331			S3C2440_NFCONF_TWRPH1(7));
332
333		set = S3C2440_NFCONF_TACLS(tacls - 1);
334		set |= S3C2440_NFCONF_TWRPH0(twrph0 - 1);
335		set |= S3C2440_NFCONF_TWRPH1(twrph1 - 1);
336		break;
337
338	default:
339		BUG();
340	}
341
342	local_irq_save(flags);
343
344	cfg = readl(info->regs + S3C2410_NFCONF);
345	cfg &= ~mask;
346	cfg |= set;
347	writel(cfg, info->regs + S3C2410_NFCONF);
348
349	local_irq_restore(flags);
350
351	dev_dbg(info->device, "NF_CONF is 0x%lx\n", cfg);
352
353	return 0;
354}
355
356/**
357 * s3c2410_nand_inithw - basic hardware initialisation
358 * @info: The hardware state.
359 *
360 * Do the basic initialisation of the hardware, using s3c2410_nand_setrate()
361 * to setup the hardware access speeds and set the controller to be enabled.
362*/
363static int s3c2410_nand_inithw(struct s3c2410_nand_info *info)
364{
365	int ret;
366
367	ret = s3c2410_nand_setrate(info);
368	if (ret < 0)
369		return ret;
370
371	switch (info->cpu_type) {
372	case TYPE_S3C2410:
373	default:
374		break;
375
376	case TYPE_S3C2440:
377	case TYPE_S3C2412:
378		/* enable the controller and de-assert nFCE */
379
380		writel(S3C2440_NFCONT_ENABLE, info->regs + S3C2440_NFCONT);
381	}
382
383	return 0;
384}
385
386/**
387 * s3c2410_nand_select_chip - select the given nand chip
388 * @this: NAND chip object.
389 * @chip: The chip number.
390 *
391 * This is called by the MTD layer to either select a given chip for the
392 * @mtd instance, or to indicate that the access has finished and the
393 * chip can be de-selected.
394 *
395 * The routine ensures that the nFCE line is correctly setup, and any
396 * platform specific selection code is called to route nFCE to the specific
397 * chip.
398 */
399static void s3c2410_nand_select_chip(struct nand_chip *this, int chip)
400{
401	struct s3c2410_nand_info *info;
402	struct s3c2410_nand_mtd *nmtd;
403	unsigned long cur;
404
405	nmtd = nand_get_controller_data(this);
406	info = nmtd->info;
407
408	if (chip != -1)
409		s3c2410_nand_clk_set_state(info, CLOCK_ENABLE);
410
411	cur = readl(info->sel_reg);
412
413	if (chip == -1) {
414		cur |= info->sel_bit;
415	} else {
416		if (nmtd->set != NULL && chip > nmtd->set->nr_chips) {
417			dev_err(info->device, "invalid chip %d\n", chip);
418			return;
419		}
420
421		if (info->platform != NULL) {
422			if (info->platform->select_chip != NULL)
423				(info->platform->select_chip) (nmtd->set, chip);
424		}
425
426		cur &= ~info->sel_bit;
427	}
428
429	writel(cur, info->sel_reg);
430
431	if (chip == -1)
432		s3c2410_nand_clk_set_state(info, CLOCK_SUSPEND);
433}
434
435/* s3c2410_nand_hwcontrol
436 *
437 * Issue command and address cycles to the chip
438*/
439
440static void s3c2410_nand_hwcontrol(struct nand_chip *chip, int cmd,
441				   unsigned int ctrl)
442{
443	struct mtd_info *mtd = nand_to_mtd(chip);
444	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
445
446	if (cmd == NAND_CMD_NONE)
447		return;
448
449	if (ctrl & NAND_CLE)
450		writeb(cmd, info->regs + S3C2410_NFCMD);
451	else
452		writeb(cmd, info->regs + S3C2410_NFADDR);
453}
454
455/* command and control functions */
456
457static void s3c2440_nand_hwcontrol(struct nand_chip *chip, int cmd,
458				   unsigned int ctrl)
459{
460	struct mtd_info *mtd = nand_to_mtd(chip);
461	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
462
463	if (cmd == NAND_CMD_NONE)
464		return;
465
466	if (ctrl & NAND_CLE)
467		writeb(cmd, info->regs + S3C2440_NFCMD);
468	else
469		writeb(cmd, info->regs + S3C2440_NFADDR);
470}
471
472/* s3c2410_nand_devready()
473 *
474 * returns 0 if the nand is busy, 1 if it is ready
475*/
476
477static int s3c2410_nand_devready(struct nand_chip *chip)
478{
479	struct mtd_info *mtd = nand_to_mtd(chip);
480	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
481	return readb(info->regs + S3C2410_NFSTAT) & S3C2410_NFSTAT_BUSY;
482}
483
484static int s3c2440_nand_devready(struct nand_chip *chip)
485{
486	struct mtd_info *mtd = nand_to_mtd(chip);
487	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
488	return readb(info->regs + S3C2440_NFSTAT) & S3C2440_NFSTAT_READY;
489}
490
491static int s3c2412_nand_devready(struct nand_chip *chip)
492{
493	struct mtd_info *mtd = nand_to_mtd(chip);
494	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
495	return readb(info->regs + S3C2412_NFSTAT) & S3C2412_NFSTAT_READY;
496}
497
498/* ECC handling functions */
499
500static int s3c2410_nand_correct_data(struct nand_chip *chip, u_char *dat,
501				     u_char *read_ecc, u_char *calc_ecc)
502{
503	struct mtd_info *mtd = nand_to_mtd(chip);
504	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
505	unsigned int diff0, diff1, diff2;
506	unsigned int bit, byte;
507
508	pr_debug("%s(%p,%p,%p,%p)\n", __func__, mtd, dat, read_ecc, calc_ecc);
509
510	diff0 = read_ecc[0] ^ calc_ecc[0];
511	diff1 = read_ecc[1] ^ calc_ecc[1];
512	diff2 = read_ecc[2] ^ calc_ecc[2];
513
514	pr_debug("%s: rd %*phN calc %*phN diff %02x%02x%02x\n",
515		 __func__, 3, read_ecc, 3, calc_ecc,
516		 diff0, diff1, diff2);
517
518	if (diff0 == 0 && diff1 == 0 && diff2 == 0)
519		return 0;		/* ECC is ok */
520
521	/* sometimes people do not think about using the ECC, so check
522	 * to see if we have an 0xff,0xff,0xff read ECC and then ignore
523	 * the error, on the assumption that this is an un-eccd page.
524	 */
525	if (read_ecc[0] == 0xff && read_ecc[1] == 0xff && read_ecc[2] == 0xff
526	    && info->platform->ignore_unset_ecc)
527		return 0;
528
529	/* Can we correct this ECC (ie, one row and column change).
530	 * Note, this is similar to the 256 error code on smartmedia */
531
532	if (((diff0 ^ (diff0 >> 1)) & 0x55) == 0x55 &&
533	    ((diff1 ^ (diff1 >> 1)) & 0x55) == 0x55 &&
534	    ((diff2 ^ (diff2 >> 1)) & 0x55) == 0x55) {
535		/* calculate the bit position of the error */
536
537		bit  = ((diff2 >> 3) & 1) |
538		       ((diff2 >> 4) & 2) |
539		       ((diff2 >> 5) & 4);
540
541		/* calculate the byte position of the error */
542
543		byte = ((diff2 << 7) & 0x100) |
544		       ((diff1 << 0) & 0x80)  |
545		       ((diff1 << 1) & 0x40)  |
546		       ((diff1 << 2) & 0x20)  |
547		       ((diff1 << 3) & 0x10)  |
548		       ((diff0 >> 4) & 0x08)  |
549		       ((diff0 >> 3) & 0x04)  |
550		       ((diff0 >> 2) & 0x02)  |
551		       ((diff0 >> 1) & 0x01);
552
553		dev_dbg(info->device, "correcting error bit %d, byte %d\n",
554			bit, byte);
555
556		dat[byte] ^= (1 << bit);
557		return 1;
558	}
559
560	/* if there is only one bit difference in the ECC, then
561	 * one of only a row or column parity has changed, which
562	 * means the error is most probably in the ECC itself */
563
564	diff0 |= (diff1 << 8);
565	diff0 |= (diff2 << 16);
566
567	/* equal to "(diff0 & ~(1 << __ffs(diff0)))" */
568	if ((diff0 & (diff0 - 1)) == 0)
569		return 1;
570
571	return -1;
572}
573
574/* ECC functions
575 *
576 * These allow the s3c2410 and s3c2440 to use the controller's ECC
577 * generator block to ECC the data as it passes through]
578*/
579
580static void s3c2410_nand_enable_hwecc(struct nand_chip *chip, int mode)
581{
582	struct s3c2410_nand_info *info;
583	unsigned long ctrl;
584
585	info = s3c2410_nand_mtd_toinfo(nand_to_mtd(chip));
586	ctrl = readl(info->regs + S3C2410_NFCONF);
587	ctrl |= S3C2410_NFCONF_INITECC;
588	writel(ctrl, info->regs + S3C2410_NFCONF);
589}
590
591static void s3c2412_nand_enable_hwecc(struct nand_chip *chip, int mode)
592{
593	struct s3c2410_nand_info *info;
594	unsigned long ctrl;
595
596	info = s3c2410_nand_mtd_toinfo(nand_to_mtd(chip));
597	ctrl = readl(info->regs + S3C2440_NFCONT);
598	writel(ctrl | S3C2412_NFCONT_INIT_MAIN_ECC,
599	       info->regs + S3C2440_NFCONT);
600}
601
602static void s3c2440_nand_enable_hwecc(struct nand_chip *chip, int mode)
603{
604	struct s3c2410_nand_info *info;
605	unsigned long ctrl;
606
607	info = s3c2410_nand_mtd_toinfo(nand_to_mtd(chip));
608	ctrl = readl(info->regs + S3C2440_NFCONT);
609	writel(ctrl | S3C2440_NFCONT_INITECC, info->regs + S3C2440_NFCONT);
610}
611
612static int s3c2410_nand_calculate_ecc(struct nand_chip *chip,
613				      const u_char *dat, u_char *ecc_code)
614{
615	struct mtd_info *mtd = nand_to_mtd(chip);
616	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
617
618	ecc_code[0] = readb(info->regs + S3C2410_NFECC + 0);
619	ecc_code[1] = readb(info->regs + S3C2410_NFECC + 1);
620	ecc_code[2] = readb(info->regs + S3C2410_NFECC + 2);
621
622	pr_debug("%s: returning ecc %*phN\n", __func__, 3, ecc_code);
623
624	return 0;
625}
626
627static int s3c2412_nand_calculate_ecc(struct nand_chip *chip,
628				      const u_char *dat, u_char *ecc_code)
629{
630	struct mtd_info *mtd = nand_to_mtd(chip);
631	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
632	unsigned long ecc = readl(info->regs + S3C2412_NFMECC0);
633
634	ecc_code[0] = ecc;
635	ecc_code[1] = ecc >> 8;
636	ecc_code[2] = ecc >> 16;
637
638	pr_debug("%s: returning ecc %*phN\n", __func__, 3, ecc_code);
639
640	return 0;
641}
642
643static int s3c2440_nand_calculate_ecc(struct nand_chip *chip,
644				      const u_char *dat, u_char *ecc_code)
645{
646	struct mtd_info *mtd = nand_to_mtd(chip);
647	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
648	unsigned long ecc = readl(info->regs + S3C2440_NFMECC0);
649
650	ecc_code[0] = ecc;
651	ecc_code[1] = ecc >> 8;
652	ecc_code[2] = ecc >> 16;
653
654	pr_debug("%s: returning ecc %06lx\n", __func__, ecc & 0xffffff);
655
656	return 0;
657}
658
659/* over-ride the standard functions for a little more speed. We can
660 * use read/write block to move the data buffers to/from the controller
661*/
662
663static void s3c2410_nand_read_buf(struct nand_chip *this, u_char *buf, int len)
664{
665	readsb(this->legacy.IO_ADDR_R, buf, len);
666}
667
668static void s3c2440_nand_read_buf(struct nand_chip *this, u_char *buf, int len)
669{
670	struct mtd_info *mtd = nand_to_mtd(this);
671	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
672
673	readsl(info->regs + S3C2440_NFDATA, buf, len >> 2);
674
675	/* cleanup if we've got less than a word to do */
676	if (len & 3) {
677		buf += len & ~3;
678
679		for (; len & 3; len--)
680			*buf++ = readb(info->regs + S3C2440_NFDATA);
681	}
682}
683
684static void s3c2410_nand_write_buf(struct nand_chip *this, const u_char *buf,
685				   int len)
686{
687	writesb(this->legacy.IO_ADDR_W, buf, len);
688}
689
690static void s3c2440_nand_write_buf(struct nand_chip *this, const u_char *buf,
691				   int len)
692{
693	struct mtd_info *mtd = nand_to_mtd(this);
694	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
695
696	writesl(info->regs + S3C2440_NFDATA, buf, len >> 2);
697
698	/* cleanup any fractional write */
699	if (len & 3) {
700		buf += len & ~3;
701
702		for (; len & 3; len--, buf++)
703			writeb(*buf, info->regs + S3C2440_NFDATA);
704	}
705}
706
707/* device management functions */
708
709static void s3c24xx_nand_remove(struct platform_device *pdev)
710{
711	struct s3c2410_nand_info *info = to_nand_info(pdev);
712
713	if (info == NULL)
714		return;
715
716	/* Release all our mtds  and their partitions, then go through
717	 * freeing the resources used
718	 */
719
720	if (info->mtds != NULL) {
721		struct s3c2410_nand_mtd *ptr = info->mtds;
722		int mtdno;
723
724		for (mtdno = 0; mtdno < info->mtd_count; mtdno++, ptr++) {
725			pr_debug("releasing mtd %d (%p)\n", mtdno, ptr);
726			WARN_ON(mtd_device_unregister(nand_to_mtd(&ptr->chip)));
727			nand_cleanup(&ptr->chip);
728		}
729	}
730
731	/* free the common resources */
732
733	if (!IS_ERR(info->clk))
734		s3c2410_nand_clk_set_state(info, CLOCK_DISABLE);
735}
736
737static int s3c2410_nand_add_partition(struct s3c2410_nand_info *info,
738				      struct s3c2410_nand_mtd *mtd,
739				      struct s3c2410_nand_set *set)
740{
741	if (set) {
742		struct mtd_info *mtdinfo = nand_to_mtd(&mtd->chip);
743
744		mtdinfo->name = set->name;
745
746		return mtd_device_register(mtdinfo, set->partitions,
747					   set->nr_partitions);
748	}
749
750	return -ENODEV;
751}
752
753static int s3c2410_nand_setup_interface(struct nand_chip *chip, int csline,
754					const struct nand_interface_config *conf)
755{
756	struct mtd_info *mtd = nand_to_mtd(chip);
757	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
758	struct s3c2410_platform_nand *pdata = info->platform;
759	const struct nand_sdr_timings *timings;
760	int tacls;
761
762	timings = nand_get_sdr_timings(conf);
763	if (IS_ERR(timings))
764		return -ENOTSUPP;
765
766	tacls = timings->tCLS_min - timings->tWP_min;
767	if (tacls < 0)
768		tacls = 0;
769
770	pdata->tacls  = DIV_ROUND_UP(tacls, 1000);
771	pdata->twrph0 = DIV_ROUND_UP(timings->tWP_min, 1000);
772	pdata->twrph1 = DIV_ROUND_UP(timings->tCLH_min, 1000);
773
774	return s3c2410_nand_setrate(info);
775}
776
777/**
778 * s3c2410_nand_init_chip - initialise a single instance of an chip
779 * @info: The base NAND controller the chip is on.
780 * @nmtd: The new controller MTD instance to fill in.
781 * @set: The information passed from the board specific platform data.
782 *
783 * Initialise the given @nmtd from the information in @info and @set. This
784 * readies the structure for use with the MTD layer functions by ensuring
785 * all pointers are setup and the necessary control routines selected.
786 */
787static void s3c2410_nand_init_chip(struct s3c2410_nand_info *info,
788				   struct s3c2410_nand_mtd *nmtd,
789				   struct s3c2410_nand_set *set)
790{
791	struct device_node *np = info->device->of_node;
792	struct nand_chip *chip = &nmtd->chip;
793	void __iomem *regs = info->regs;
794
795	nand_set_flash_node(chip, set->of_node);
796
797	chip->legacy.write_buf    = s3c2410_nand_write_buf;
798	chip->legacy.read_buf     = s3c2410_nand_read_buf;
799	chip->legacy.select_chip  = s3c2410_nand_select_chip;
800	chip->legacy.chip_delay   = 50;
801	nand_set_controller_data(chip, nmtd);
802	chip->options	   = set->options;
803	chip->controller   = &info->controller;
804
805	/*
806	 * let's keep behavior unchanged for legacy boards booting via pdata and
807	 * auto-detect timings only when booting with a device tree.
808	 */
809	if (!np)
810		chip->options |= NAND_KEEP_TIMINGS;
811
812	switch (info->cpu_type) {
813	case TYPE_S3C2410:
814		chip->legacy.IO_ADDR_W = regs + S3C2410_NFDATA;
815		info->sel_reg   = regs + S3C2410_NFCONF;
816		info->sel_bit	= S3C2410_NFCONF_nFCE;
817		chip->legacy.cmd_ctrl  = s3c2410_nand_hwcontrol;
818		chip->legacy.dev_ready = s3c2410_nand_devready;
819		break;
820
821	case TYPE_S3C2440:
822		chip->legacy.IO_ADDR_W = regs + S3C2440_NFDATA;
823		info->sel_reg   = regs + S3C2440_NFCONT;
824		info->sel_bit	= S3C2440_NFCONT_nFCE;
825		chip->legacy.cmd_ctrl  = s3c2440_nand_hwcontrol;
826		chip->legacy.dev_ready = s3c2440_nand_devready;
827		chip->legacy.read_buf  = s3c2440_nand_read_buf;
828		chip->legacy.write_buf	= s3c2440_nand_write_buf;
829		break;
830
831	case TYPE_S3C2412:
832		chip->legacy.IO_ADDR_W = regs + S3C2440_NFDATA;
833		info->sel_reg   = regs + S3C2440_NFCONT;
834		info->sel_bit	= S3C2412_NFCONT_nFCE0;
835		chip->legacy.cmd_ctrl  = s3c2440_nand_hwcontrol;
836		chip->legacy.dev_ready = s3c2412_nand_devready;
837
838		if (readl(regs + S3C2410_NFCONF) & S3C2412_NFCONF_NANDBOOT)
839			dev_info(info->device, "System booted from NAND\n");
840
841		break;
842	}
843
844	chip->legacy.IO_ADDR_R = chip->legacy.IO_ADDR_W;
845
846	nmtd->info	   = info;
847	nmtd->set	   = set;
848
849	chip->ecc.engine_type = info->platform->engine_type;
850
851	/*
852	 * If you use u-boot BBT creation code, specifying this flag will
853	 * let the kernel fish out the BBT from the NAND.
854	 */
855	if (set->flash_bbt)
856		chip->bbt_options |= NAND_BBT_USE_FLASH;
857}
858
859/**
860 * s3c2410_nand_attach_chip - Init the ECC engine after NAND scan
861 * @chip: The NAND chip
862 *
863 * This hook is called by the core after the identification of the NAND chip,
864 * once the relevant per-chip information is up to date.. This call ensure that
865 * we update the internal state accordingly.
866 *
867 * The internal state is currently limited to the ECC state information.
868*/
869static int s3c2410_nand_attach_chip(struct nand_chip *chip)
870{
871	struct mtd_info *mtd = nand_to_mtd(chip);
872	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
873
874	switch (chip->ecc.engine_type) {
875
876	case NAND_ECC_ENGINE_TYPE_NONE:
877		dev_info(info->device, "ECC disabled\n");
878		break;
879
880	case NAND_ECC_ENGINE_TYPE_SOFT:
881		/*
882		 * This driver expects Hamming based ECC when engine_type is set
883		 * to NAND_ECC_ENGINE_TYPE_SOFT. Force ecc.algo to
884		 * NAND_ECC_ALGO_HAMMING to avoid adding an extra ecc_algo field
885		 * to s3c2410_platform_nand.
886		 */
887		chip->ecc.algo = NAND_ECC_ALGO_HAMMING;
888		dev_info(info->device, "soft ECC\n");
889		break;
890
891	case NAND_ECC_ENGINE_TYPE_ON_HOST:
892		chip->ecc.calculate = s3c2410_nand_calculate_ecc;
893		chip->ecc.correct   = s3c2410_nand_correct_data;
894		chip->ecc.strength  = 1;
895
896		switch (info->cpu_type) {
897		case TYPE_S3C2410:
898			chip->ecc.hwctl	    = s3c2410_nand_enable_hwecc;
899			chip->ecc.calculate = s3c2410_nand_calculate_ecc;
900			break;
901
902		case TYPE_S3C2412:
903			chip->ecc.hwctl     = s3c2412_nand_enable_hwecc;
904			chip->ecc.calculate = s3c2412_nand_calculate_ecc;
905			break;
906
907		case TYPE_S3C2440:
908			chip->ecc.hwctl     = s3c2440_nand_enable_hwecc;
909			chip->ecc.calculate = s3c2440_nand_calculate_ecc;
910			break;
911		}
912
913		dev_dbg(info->device, "chip %p => page shift %d\n",
914			chip, chip->page_shift);
915
916		/* change the behaviour depending on whether we are using
917		 * the large or small page nand device */
918		if (chip->page_shift > 10) {
919			chip->ecc.size	    = 256;
920			chip->ecc.bytes	    = 3;
921		} else {
922			chip->ecc.size	    = 512;
923			chip->ecc.bytes	    = 3;
924			mtd_set_ooblayout(nand_to_mtd(chip),
925					  &s3c2410_ooblayout_ops);
926		}
927
928		dev_info(info->device, "hardware ECC\n");
929		break;
930
931	default:
932		dev_err(info->device, "invalid ECC mode!\n");
933		return -EINVAL;
934	}
935
936	if (chip->bbt_options & NAND_BBT_USE_FLASH)
937		chip->options |= NAND_SKIP_BBTSCAN;
938
939	return 0;
940}
941
942static const struct nand_controller_ops s3c24xx_nand_controller_ops = {
943	.attach_chip = s3c2410_nand_attach_chip,
944	.setup_interface = s3c2410_nand_setup_interface,
945};
946
947static const struct of_device_id s3c24xx_nand_dt_ids[] = {
948	{
949		.compatible = "samsung,s3c2410-nand",
950		.data = &s3c2410_nand_devtype_data,
951	}, {
952		/* also compatible with s3c6400 */
953		.compatible = "samsung,s3c2412-nand",
954		.data = &s3c2412_nand_devtype_data,
955	}, {
956		.compatible = "samsung,s3c2440-nand",
957		.data = &s3c2440_nand_devtype_data,
958	},
959	{ /* sentinel */ }
960};
961MODULE_DEVICE_TABLE(of, s3c24xx_nand_dt_ids);
962
963static int s3c24xx_nand_probe_dt(struct platform_device *pdev)
964{
965	const struct s3c24XX_nand_devtype_data *devtype_data;
966	struct s3c2410_platform_nand *pdata;
967	struct s3c2410_nand_info *info = platform_get_drvdata(pdev);
968	struct device_node *np = pdev->dev.of_node, *child;
969	struct s3c2410_nand_set *sets;
970
971	devtype_data = of_device_get_match_data(&pdev->dev);
972	if (!devtype_data)
973		return -ENODEV;
974
975	info->cpu_type = devtype_data->type;
976
977	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
978	if (!pdata)
979		return -ENOMEM;
980
981	pdev->dev.platform_data = pdata;
982
983	pdata->nr_sets = of_get_child_count(np);
984	if (!pdata->nr_sets)
985		return 0;
986
987	sets = devm_kcalloc(&pdev->dev, pdata->nr_sets, sizeof(*sets),
988			    GFP_KERNEL);
989	if (!sets)
990		return -ENOMEM;
991
992	pdata->sets = sets;
993
994	for_each_available_child_of_node(np, child) {
995		sets->name = (char *)child->name;
996		sets->of_node = child;
997		sets->nr_chips = 1;
998
999		of_node_get(child);
1000
1001		sets++;
1002	}
1003
1004	return 0;
1005}
1006
1007static int s3c24xx_nand_probe_pdata(struct platform_device *pdev)
1008{
1009	struct s3c2410_nand_info *info = platform_get_drvdata(pdev);
1010
1011	info->cpu_type = platform_get_device_id(pdev)->driver_data;
1012
1013	return 0;
1014}
1015
1016/* s3c24xx_nand_probe
1017 *
1018 * called by device layer when it finds a device matching
1019 * one our driver can handled. This code checks to see if
1020 * it can allocate all necessary resources then calls the
1021 * nand layer to look for devices
1022*/
1023static int s3c24xx_nand_probe(struct platform_device *pdev)
1024{
1025	struct s3c2410_platform_nand *plat;
1026	struct s3c2410_nand_info *info;
1027	struct s3c2410_nand_mtd *nmtd;
1028	struct s3c2410_nand_set *sets;
1029	struct resource *res;
1030	int err = 0;
1031	int size;
1032	int nr_sets;
1033	int setno;
1034
1035	info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
1036	if (info == NULL) {
1037		err = -ENOMEM;
1038		goto exit_error;
1039	}
1040
1041	platform_set_drvdata(pdev, info);
1042
1043	nand_controller_init(&info->controller);
1044	info->controller.ops = &s3c24xx_nand_controller_ops;
1045
1046	/* get the clock source and enable it */
1047
1048	info->clk = devm_clk_get(&pdev->dev, "nand");
1049	if (IS_ERR(info->clk)) {
1050		dev_err(&pdev->dev, "failed to get clock\n");
1051		err = -ENOENT;
1052		goto exit_error;
1053	}
1054
1055	s3c2410_nand_clk_set_state(info, CLOCK_ENABLE);
1056
1057	if (pdev->dev.of_node)
1058		err = s3c24xx_nand_probe_dt(pdev);
1059	else
1060		err = s3c24xx_nand_probe_pdata(pdev);
1061
1062	if (err)
1063		goto exit_error;
1064
1065	plat = to_nand_plat(pdev);
1066
1067	/* allocate and map the resource */
1068
1069	/* currently we assume we have the one resource */
1070	res = pdev->resource;
1071	size = resource_size(res);
1072
1073	info->device	= &pdev->dev;
1074	info->platform	= plat;
1075
1076	info->regs = devm_ioremap_resource(&pdev->dev, res);
1077	if (IS_ERR(info->regs)) {
1078		err = PTR_ERR(info->regs);
1079		goto exit_error;
1080	}
1081
1082	dev_dbg(&pdev->dev, "mapped registers at %p\n", info->regs);
1083
1084	if (!plat->sets || plat->nr_sets < 1) {
1085		err = -EINVAL;
1086		goto exit_error;
1087	}
1088
1089	sets = plat->sets;
1090	nr_sets = plat->nr_sets;
1091
1092	info->mtd_count = nr_sets;
1093
1094	/* allocate our information */
1095
1096	size = nr_sets * sizeof(*info->mtds);
1097	info->mtds = devm_kzalloc(&pdev->dev, size, GFP_KERNEL);
1098	if (info->mtds == NULL) {
1099		err = -ENOMEM;
1100		goto exit_error;
1101	}
1102
1103	/* initialise all possible chips */
1104
1105	nmtd = info->mtds;
1106
1107	for (setno = 0; setno < nr_sets; setno++, nmtd++, sets++) {
1108		struct mtd_info *mtd = nand_to_mtd(&nmtd->chip);
1109
1110		pr_debug("initialising set %d (%p, info %p)\n",
1111			 setno, nmtd, info);
1112
1113		mtd->dev.parent = &pdev->dev;
1114		s3c2410_nand_init_chip(info, nmtd, sets);
1115
1116		err = nand_scan(&nmtd->chip, sets ? sets->nr_chips : 1);
1117		if (err)
1118			goto exit_error;
1119
1120		s3c2410_nand_add_partition(info, nmtd, sets);
1121	}
1122
1123	/* initialise the hardware */
1124	err = s3c2410_nand_inithw(info);
1125	if (err != 0)
1126		goto exit_error;
1127
1128	if (allow_clk_suspend(info)) {
1129		dev_info(&pdev->dev, "clock idle support enabled\n");
1130		s3c2410_nand_clk_set_state(info, CLOCK_SUSPEND);
1131	}
1132
1133	return 0;
1134
1135 exit_error:
1136	s3c24xx_nand_remove(pdev);
1137
1138	if (err == 0)
1139		err = -EINVAL;
1140	return err;
1141}
1142
1143/* PM Support */
1144#ifdef CONFIG_PM
1145
1146static int s3c24xx_nand_suspend(struct platform_device *dev, pm_message_t pm)
1147{
1148	struct s3c2410_nand_info *info = platform_get_drvdata(dev);
1149
1150	if (info) {
1151		info->save_sel = readl(info->sel_reg);
1152
1153		/* For the moment, we must ensure nFCE is high during
1154		 * the time we are suspended. This really should be
1155		 * handled by suspending the MTDs we are using, but
1156		 * that is currently not the case. */
1157
1158		writel(info->save_sel | info->sel_bit, info->sel_reg);
1159
1160		s3c2410_nand_clk_set_state(info, CLOCK_DISABLE);
1161	}
1162
1163	return 0;
1164}
1165
1166static int s3c24xx_nand_resume(struct platform_device *dev)
1167{
1168	struct s3c2410_nand_info *info = platform_get_drvdata(dev);
1169	unsigned long sel;
1170
1171	if (info) {
1172		s3c2410_nand_clk_set_state(info, CLOCK_ENABLE);
1173		s3c2410_nand_inithw(info);
1174
1175		/* Restore the state of the nFCE line. */
1176
1177		sel = readl(info->sel_reg);
1178		sel &= ~info->sel_bit;
1179		sel |= info->save_sel & info->sel_bit;
1180		writel(sel, info->sel_reg);
1181
1182		s3c2410_nand_clk_set_state(info, CLOCK_SUSPEND);
1183	}
1184
1185	return 0;
1186}
1187
1188#else
1189#define s3c24xx_nand_suspend NULL
1190#define s3c24xx_nand_resume NULL
1191#endif
1192
1193/* driver device registration */
1194
1195static const struct platform_device_id s3c24xx_driver_ids[] = {
1196	{
1197		.name		= "s3c2410-nand",
1198		.driver_data	= TYPE_S3C2410,
1199	}, {
1200		.name		= "s3c2440-nand",
1201		.driver_data	= TYPE_S3C2440,
1202	}, {
1203		.name		= "s3c2412-nand",
1204		.driver_data	= TYPE_S3C2412,
1205	}, {
1206		.name		= "s3c6400-nand",
1207		.driver_data	= TYPE_S3C2412, /* compatible with 2412 */
1208	},
1209	{ }
1210};
1211
1212MODULE_DEVICE_TABLE(platform, s3c24xx_driver_ids);
1213
1214static struct platform_driver s3c24xx_nand_driver = {
1215	.probe		= s3c24xx_nand_probe,
1216	.remove_new	= s3c24xx_nand_remove,
1217	.suspend	= s3c24xx_nand_suspend,
1218	.resume		= s3c24xx_nand_resume,
1219	.id_table	= s3c24xx_driver_ids,
1220	.driver		= {
1221		.name	= "s3c24xx-nand",
1222		.of_match_table = s3c24xx_nand_dt_ids,
1223	},
1224};
1225
1226module_platform_driver(s3c24xx_nand_driver);
1227
1228MODULE_LICENSE("GPL");
1229MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
1230MODULE_DESCRIPTION("S3C24XX MTD NAND driver");
1231