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#include <linux/of_device.h>
30
31#include <linux/mtd/mtd.h>
32#include <linux/mtd/rawnand.h>
33#include <linux/mtd/nand_ecc.h>
34#include <linux/mtd/partitions.h>
35
36#include <linux/platform_data/mtd-nand-s3c2410.h>
37
38#define S3C2410_NFREG(x) (x)
39
40#define S3C2410_NFCONF		S3C2410_NFREG(0x00)
41#define S3C2410_NFCMD		S3C2410_NFREG(0x04)
42#define S3C2410_NFADDR		S3C2410_NFREG(0x08)
43#define S3C2410_NFDATA		S3C2410_NFREG(0x0C)
44#define S3C2410_NFSTAT		S3C2410_NFREG(0x10)
45#define S3C2410_NFECC		S3C2410_NFREG(0x14)
46#define S3C2440_NFCONT		S3C2410_NFREG(0x04)
47#define S3C2440_NFCMD		S3C2410_NFREG(0x08)
48#define S3C2440_NFADDR		S3C2410_NFREG(0x0C)
49#define S3C2440_NFDATA		S3C2410_NFREG(0x10)
50#define S3C2440_NFSTAT		S3C2410_NFREG(0x20)
51#define S3C2440_NFMECC0		S3C2410_NFREG(0x2C)
52#define S3C2412_NFSTAT		S3C2410_NFREG(0x28)
53#define S3C2412_NFMECC0		S3C2410_NFREG(0x34)
54#define S3C2410_NFCONF_EN		(1<<15)
55#define S3C2410_NFCONF_INITECC		(1<<12)
56#define S3C2410_NFCONF_nFCE		(1<<11)
57#define S3C2410_NFCONF_TACLS(x)		((x)<<8)
58#define S3C2410_NFCONF_TWRPH0(x)	((x)<<4)
59#define S3C2410_NFCONF_TWRPH1(x)	((x)<<0)
60#define S3C2410_NFSTAT_BUSY		(1<<0)
61#define S3C2440_NFCONF_TACLS(x)		((x)<<12)
62#define S3C2440_NFCONF_TWRPH0(x)	((x)<<8)
63#define S3C2440_NFCONF_TWRPH1(x)	((x)<<4)
64#define S3C2440_NFCONT_INITECC		(1<<4)
65#define S3C2440_NFCONT_nFCE		(1<<1)
66#define S3C2440_NFCONT_ENABLE		(1<<0)
67#define S3C2440_NFSTAT_READY		(1<<0)
68#define S3C2412_NFCONF_NANDBOOT		(1<<31)
69#define S3C2412_NFCONT_INIT_MAIN_ECC	(1<<5)
70#define S3C2412_NFCONT_nFCE0		(1<<1)
71#define S3C2412_NFSTAT_READY		(1<<0)
72
73/* new oob placement block for use with hardware ecc generation
74 */
75static int s3c2410_ooblayout_ecc(struct mtd_info *mtd, int section,
76				 struct mtd_oob_region *oobregion)
77{
78	if (section)
79		return -ERANGE;
80
81	oobregion->offset = 0;
82	oobregion->length = 3;
83
84	return 0;
85}
86
87static int s3c2410_ooblayout_free(struct mtd_info *mtd, int section,
88				  struct mtd_oob_region *oobregion)
89{
90	if (section)
91		return -ERANGE;
92
93	oobregion->offset = 8;
94	oobregion->length = 8;
95
96	return 0;
97}
98
99static const struct mtd_ooblayout_ops s3c2410_ooblayout_ops = {
100	.ecc = s3c2410_ooblayout_ecc,
101	.free = s3c2410_ooblayout_free,
102};
103
104/* controller and mtd information */
105
106struct s3c2410_nand_info;
107
108/**
109 * struct s3c2410_nand_mtd - driver MTD structure
110 * @mtd: The MTD instance to pass to the MTD layer.
111 * @chip: The NAND chip information.
112 * @set: The platform information supplied for this set of NAND chips.
113 * @info: Link back to the hardware information.
114*/
115struct s3c2410_nand_mtd {
116	struct nand_chip		chip;
117	struct s3c2410_nand_set		*set;
118	struct s3c2410_nand_info	*info;
119};
120
121enum s3c_cpu_type {
122	TYPE_S3C2410,
123	TYPE_S3C2412,
124	TYPE_S3C2440,
125};
126
127enum s3c_nand_clk_state {
128	CLOCK_DISABLE	= 0,
129	CLOCK_ENABLE,
130	CLOCK_SUSPEND,
131};
132
133/* overview of the s3c2410 nand state */
134
135/**
136 * struct s3c2410_nand_info - NAND controller state.
137 * @mtds: An array of MTD instances on this controoler.
138 * @platform: The platform data for this board.
139 * @device: The platform device we bound to.
140 * @clk: The clock resource for this controller.
141 * @regs: The area mapped for the hardware registers.
142 * @sel_reg: Pointer to the register controlling the NAND selection.
143 * @sel_bit: The bit in @sel_reg to select the NAND chip.
144 * @mtd_count: The number of MTDs created from this controller.
145 * @save_sel: The contents of @sel_reg to be saved over suspend.
146 * @clk_rate: The clock rate from @clk.
147 * @clk_state: The current clock state.
148 * @cpu_type: The exact type of this controller.
149 */
150struct s3c2410_nand_info {
151	/* mtd info */
152	struct nand_controller		controller;
153	struct s3c2410_nand_mtd		*mtds;
154	struct s3c2410_platform_nand	*platform;
155
156	/* device info */
157	struct device			*device;
158	struct clk			*clk;
159	void __iomem			*regs;
160	void __iomem			*sel_reg;
161	int				sel_bit;
162	int				mtd_count;
163	unsigned long			save_sel;
164	unsigned long			clk_rate;
165	enum s3c_nand_clk_state		clk_state;
166
167	enum s3c_cpu_type		cpu_type;
168
169#ifdef CONFIG_ARM_S3C24XX_CPUFREQ
170	struct notifier_block	freq_transition;
171#endif
172};
173
174struct s3c24XX_nand_devtype_data {
175	enum s3c_cpu_type type;
176};
177
178static const struct s3c24XX_nand_devtype_data s3c2410_nand_devtype_data = {
179	.type = TYPE_S3C2410,
180};
181
182static const struct s3c24XX_nand_devtype_data s3c2412_nand_devtype_data = {
183	.type = TYPE_S3C2412,
184};
185
186static const struct s3c24XX_nand_devtype_data s3c2440_nand_devtype_data = {
187	.type = TYPE_S3C2440,
188};
189
190/* conversion functions */
191
192static struct s3c2410_nand_mtd *s3c2410_nand_mtd_toours(struct mtd_info *mtd)
193{
194	return container_of(mtd_to_nand(mtd), struct s3c2410_nand_mtd,
195			    chip);
196}
197
198static struct s3c2410_nand_info *s3c2410_nand_mtd_toinfo(struct mtd_info *mtd)
199{
200	return s3c2410_nand_mtd_toours(mtd)->info;
201}
202
203static struct s3c2410_nand_info *to_nand_info(struct platform_device *dev)
204{
205	return platform_get_drvdata(dev);
206}
207
208static struct s3c2410_platform_nand *to_nand_plat(struct platform_device *dev)
209{
210	return dev_get_platdata(&dev->dev);
211}
212
213static inline int allow_clk_suspend(struct s3c2410_nand_info *info)
214{
215#ifdef CONFIG_MTD_NAND_S3C2410_CLKSTOP
216	return 1;
217#else
218	return 0;
219#endif
220}
221
222/**
223 * s3c2410_nand_clk_set_state - Enable, disable or suspend NAND clock.
224 * @info: The controller instance.
225 * @new_state: State to which clock should be set.
226 */
227static void s3c2410_nand_clk_set_state(struct s3c2410_nand_info *info,
228		enum s3c_nand_clk_state new_state)
229{
230	if (!allow_clk_suspend(info) && new_state == CLOCK_SUSPEND)
231		return;
232
233	if (info->clk_state == CLOCK_ENABLE) {
234		if (new_state != CLOCK_ENABLE)
235			clk_disable_unprepare(info->clk);
236	} else {
237		if (new_state == CLOCK_ENABLE)
238			clk_prepare_enable(info->clk);
239	}
240
241	info->clk_state = new_state;
242}
243
244/* timing calculations */
245
246#define NS_IN_KHZ 1000000
247
248/**
249 * s3c_nand_calc_rate - calculate timing data.
250 * @wanted: The cycle time in nanoseconds.
251 * @clk: The clock rate in kHz.
252 * @max: The maximum divider value.
253 *
254 * Calculate the timing value from the given parameters.
255 */
256static int s3c_nand_calc_rate(int wanted, unsigned long clk, int max)
257{
258	int result;
259
260	result = DIV_ROUND_UP((wanted * clk), NS_IN_KHZ);
261
262	pr_debug("result %d from %ld, %d\n", result, clk, wanted);
263
264	if (result > max) {
265		pr_err("%d ns is too big for current clock rate %ld\n",
266			wanted, clk);
267		return -1;
268	}
269
270	if (result < 1)
271		result = 1;
272
273	return result;
274}
275
276#define to_ns(ticks, clk) (((ticks) * NS_IN_KHZ) / (unsigned int)(clk))
277
278/* controller setup */
279
280/**
281 * s3c2410_nand_setrate - setup controller timing information.
282 * @info: The controller instance.
283 *
284 * Given the information supplied by the platform, calculate and set
285 * the necessary timing registers in the hardware to generate the
286 * necessary timing cycles to the hardware.
287 */
288static int s3c2410_nand_setrate(struct s3c2410_nand_info *info)
289{
290	struct s3c2410_platform_nand *plat = info->platform;
291	int tacls_max = (info->cpu_type == TYPE_S3C2412) ? 8 : 4;
292	int tacls, twrph0, twrph1;
293	unsigned long clkrate = clk_get_rate(info->clk);
294	unsigned long set, cfg, mask;
295	unsigned long flags;
296
297	/* calculate the timing information for the controller */
298
299	info->clk_rate = clkrate;
300	clkrate /= 1000;	/* turn clock into kHz for ease of use */
301
302	if (plat != NULL) {
303		tacls = s3c_nand_calc_rate(plat->tacls, clkrate, tacls_max);
304		twrph0 = s3c_nand_calc_rate(plat->twrph0, clkrate, 8);
305		twrph1 = s3c_nand_calc_rate(plat->twrph1, clkrate, 8);
306	} else {
307		/* default timings */
308		tacls = tacls_max;
309		twrph0 = 8;
310		twrph1 = 8;
311	}
312
313	if (tacls < 0 || twrph0 < 0 || twrph1 < 0) {
314		dev_err(info->device, "cannot get suitable timings\n");
315		return -EINVAL;
316	}
317
318	dev_info(info->device, "Tacls=%d, %dns Twrph0=%d %dns, Twrph1=%d %dns\n",
319		tacls, to_ns(tacls, clkrate), twrph0, to_ns(twrph0, clkrate),
320						twrph1, to_ns(twrph1, clkrate));
321
322	switch (info->cpu_type) {
323	case TYPE_S3C2410:
324		mask = (S3C2410_NFCONF_TACLS(3) |
325			S3C2410_NFCONF_TWRPH0(7) |
326			S3C2410_NFCONF_TWRPH1(7));
327		set = S3C2410_NFCONF_EN;
328		set |= S3C2410_NFCONF_TACLS(tacls - 1);
329		set |= S3C2410_NFCONF_TWRPH0(twrph0 - 1);
330		set |= S3C2410_NFCONF_TWRPH1(twrph1 - 1);
331		break;
332
333	case TYPE_S3C2440:
334	case TYPE_S3C2412:
335		mask = (S3C2440_NFCONF_TACLS(tacls_max - 1) |
336			S3C2440_NFCONF_TWRPH0(7) |
337			S3C2440_NFCONF_TWRPH1(7));
338
339		set = S3C2440_NFCONF_TACLS(tacls - 1);
340		set |= S3C2440_NFCONF_TWRPH0(twrph0 - 1);
341		set |= S3C2440_NFCONF_TWRPH1(twrph1 - 1);
342		break;
343
344	default:
345		BUG();
346	}
347
348	local_irq_save(flags);
349
350	cfg = readl(info->regs + S3C2410_NFCONF);
351	cfg &= ~mask;
352	cfg |= set;
353	writel(cfg, info->regs + S3C2410_NFCONF);
354
355	local_irq_restore(flags);
356
357	dev_dbg(info->device, "NF_CONF is 0x%lx\n", cfg);
358
359	return 0;
360}
361
362/**
363 * s3c2410_nand_inithw - basic hardware initialisation
364 * @info: The hardware state.
365 *
366 * Do the basic initialisation of the hardware, using s3c2410_nand_setrate()
367 * to setup the hardware access speeds and set the controller to be enabled.
368*/
369static int s3c2410_nand_inithw(struct s3c2410_nand_info *info)
370{
371	int ret;
372
373	ret = s3c2410_nand_setrate(info);
374	if (ret < 0)
375		return ret;
376
377	switch (info->cpu_type) {
378	case TYPE_S3C2410:
379	default:
380		break;
381
382	case TYPE_S3C2440:
383	case TYPE_S3C2412:
384		/* enable the controller and de-assert nFCE */
385
386		writel(S3C2440_NFCONT_ENABLE, info->regs + S3C2440_NFCONT);
387	}
388
389	return 0;
390}
391
392/**
393 * s3c2410_nand_select_chip - select the given nand chip
394 * @this: NAND chip object.
395 * @chip: The chip number.
396 *
397 * This is called by the MTD layer to either select a given chip for the
398 * @mtd instance, or to indicate that the access has finished and the
399 * chip can be de-selected.
400 *
401 * The routine ensures that the nFCE line is correctly setup, and any
402 * platform specific selection code is called to route nFCE to the specific
403 * chip.
404 */
405static void s3c2410_nand_select_chip(struct nand_chip *this, int chip)
406{
407	struct s3c2410_nand_info *info;
408	struct s3c2410_nand_mtd *nmtd;
409	unsigned long cur;
410
411	nmtd = nand_get_controller_data(this);
412	info = nmtd->info;
413
414	if (chip != -1)
415		s3c2410_nand_clk_set_state(info, CLOCK_ENABLE);
416
417	cur = readl(info->sel_reg);
418
419	if (chip == -1) {
420		cur |= info->sel_bit;
421	} else {
422		if (nmtd->set != NULL && chip > nmtd->set->nr_chips) {
423			dev_err(info->device, "invalid chip %d\n", chip);
424			return;
425		}
426
427		if (info->platform != NULL) {
428			if (info->platform->select_chip != NULL)
429				(info->platform->select_chip) (nmtd->set, chip);
430		}
431
432		cur &= ~info->sel_bit;
433	}
434
435	writel(cur, info->sel_reg);
436
437	if (chip == -1)
438		s3c2410_nand_clk_set_state(info, CLOCK_SUSPEND);
439}
440
441/* s3c2410_nand_hwcontrol
442 *
443 * Issue command and address cycles to the chip
444*/
445
446static void s3c2410_nand_hwcontrol(struct nand_chip *chip, int cmd,
447				   unsigned int ctrl)
448{
449	struct mtd_info *mtd = nand_to_mtd(chip);
450	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
451
452	if (cmd == NAND_CMD_NONE)
453		return;
454
455	if (ctrl & NAND_CLE)
456		writeb(cmd, info->regs + S3C2410_NFCMD);
457	else
458		writeb(cmd, info->regs + S3C2410_NFADDR);
459}
460
461/* command and control functions */
462
463static void s3c2440_nand_hwcontrol(struct nand_chip *chip, int cmd,
464				   unsigned int ctrl)
465{
466	struct mtd_info *mtd = nand_to_mtd(chip);
467	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
468
469	if (cmd == NAND_CMD_NONE)
470		return;
471
472	if (ctrl & NAND_CLE)
473		writeb(cmd, info->regs + S3C2440_NFCMD);
474	else
475		writeb(cmd, info->regs + S3C2440_NFADDR);
476}
477
478/* s3c2410_nand_devready()
479 *
480 * returns 0 if the nand is busy, 1 if it is ready
481*/
482
483static int s3c2410_nand_devready(struct nand_chip *chip)
484{
485	struct mtd_info *mtd = nand_to_mtd(chip);
486	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
487	return readb(info->regs + S3C2410_NFSTAT) & S3C2410_NFSTAT_BUSY;
488}
489
490static int s3c2440_nand_devready(struct nand_chip *chip)
491{
492	struct mtd_info *mtd = nand_to_mtd(chip);
493	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
494	return readb(info->regs + S3C2440_NFSTAT) & S3C2440_NFSTAT_READY;
495}
496
497static int s3c2412_nand_devready(struct nand_chip *chip)
498{
499	struct mtd_info *mtd = nand_to_mtd(chip);
500	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
501	return readb(info->regs + S3C2412_NFSTAT) & S3C2412_NFSTAT_READY;
502}
503
504/* ECC handling functions */
505
506static int s3c2410_nand_correct_data(struct nand_chip *chip, u_char *dat,
507				     u_char *read_ecc, u_char *calc_ecc)
508{
509	struct mtd_info *mtd = nand_to_mtd(chip);
510	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
511	unsigned int diff0, diff1, diff2;
512	unsigned int bit, byte;
513
514	pr_debug("%s(%p,%p,%p,%p)\n", __func__, mtd, dat, read_ecc, calc_ecc);
515
516	diff0 = read_ecc[0] ^ calc_ecc[0];
517	diff1 = read_ecc[1] ^ calc_ecc[1];
518	diff2 = read_ecc[2] ^ calc_ecc[2];
519
520	pr_debug("%s: rd %*phN calc %*phN diff %02x%02x%02x\n",
521		 __func__, 3, read_ecc, 3, calc_ecc,
522		 diff0, diff1, diff2);
523
524	if (diff0 == 0 && diff1 == 0 && diff2 == 0)
525		return 0;		/* ECC is ok */
526
527	/* sometimes people do not think about using the ECC, so check
528	 * to see if we have an 0xff,0xff,0xff read ECC and then ignore
529	 * the error, on the assumption that this is an un-eccd page.
530	 */
531	if (read_ecc[0] == 0xff && read_ecc[1] == 0xff && read_ecc[2] == 0xff
532	    && info->platform->ignore_unset_ecc)
533		return 0;
534
535	/* Can we correct this ECC (ie, one row and column change).
536	 * Note, this is similar to the 256 error code on smartmedia */
537
538	if (((diff0 ^ (diff0 >> 1)) & 0x55) == 0x55 &&
539	    ((diff1 ^ (diff1 >> 1)) & 0x55) == 0x55 &&
540	    ((diff2 ^ (diff2 >> 1)) & 0x55) == 0x55) {
541		/* calculate the bit position of the error */
542
543		bit  = ((diff2 >> 3) & 1) |
544		       ((diff2 >> 4) & 2) |
545		       ((diff2 >> 5) & 4);
546
547		/* calculate the byte position of the error */
548
549		byte = ((diff2 << 7) & 0x100) |
550		       ((diff1 << 0) & 0x80)  |
551		       ((diff1 << 1) & 0x40)  |
552		       ((diff1 << 2) & 0x20)  |
553		       ((diff1 << 3) & 0x10)  |
554		       ((diff0 >> 4) & 0x08)  |
555		       ((diff0 >> 3) & 0x04)  |
556		       ((diff0 >> 2) & 0x02)  |
557		       ((diff0 >> 1) & 0x01);
558
559		dev_dbg(info->device, "correcting error bit %d, byte %d\n",
560			bit, byte);
561
562		dat[byte] ^= (1 << bit);
563		return 1;
564	}
565
566	/* if there is only one bit difference in the ECC, then
567	 * one of only a row or column parity has changed, which
568	 * means the error is most probably in the ECC itself */
569
570	diff0 |= (diff1 << 8);
571	diff0 |= (diff2 << 16);
572
573	/* equal to "(diff0 & ~(1 << __ffs(diff0)))" */
574	if ((diff0 & (diff0 - 1)) == 0)
575		return 1;
576
577	return -1;
578}
579
580/* ECC functions
581 *
582 * These allow the s3c2410 and s3c2440 to use the controller's ECC
583 * generator block to ECC the data as it passes through]
584*/
585
586static void s3c2410_nand_enable_hwecc(struct nand_chip *chip, int mode)
587{
588	struct s3c2410_nand_info *info;
589	unsigned long ctrl;
590
591	info = s3c2410_nand_mtd_toinfo(nand_to_mtd(chip));
592	ctrl = readl(info->regs + S3C2410_NFCONF);
593	ctrl |= S3C2410_NFCONF_INITECC;
594	writel(ctrl, info->regs + S3C2410_NFCONF);
595}
596
597static void s3c2412_nand_enable_hwecc(struct nand_chip *chip, int mode)
598{
599	struct s3c2410_nand_info *info;
600	unsigned long ctrl;
601
602	info = s3c2410_nand_mtd_toinfo(nand_to_mtd(chip));
603	ctrl = readl(info->regs + S3C2440_NFCONT);
604	writel(ctrl | S3C2412_NFCONT_INIT_MAIN_ECC,
605	       info->regs + S3C2440_NFCONT);
606}
607
608static void s3c2440_nand_enable_hwecc(struct nand_chip *chip, int mode)
609{
610	struct s3c2410_nand_info *info;
611	unsigned long ctrl;
612
613	info = s3c2410_nand_mtd_toinfo(nand_to_mtd(chip));
614	ctrl = readl(info->regs + S3C2440_NFCONT);
615	writel(ctrl | S3C2440_NFCONT_INITECC, info->regs + S3C2440_NFCONT);
616}
617
618static int s3c2410_nand_calculate_ecc(struct nand_chip *chip,
619				      const u_char *dat, u_char *ecc_code)
620{
621	struct mtd_info *mtd = nand_to_mtd(chip);
622	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
623
624	ecc_code[0] = readb(info->regs + S3C2410_NFECC + 0);
625	ecc_code[1] = readb(info->regs + S3C2410_NFECC + 1);
626	ecc_code[2] = readb(info->regs + S3C2410_NFECC + 2);
627
628	pr_debug("%s: returning ecc %*phN\n", __func__, 3, ecc_code);
629
630	return 0;
631}
632
633static int s3c2412_nand_calculate_ecc(struct nand_chip *chip,
634				      const u_char *dat, u_char *ecc_code)
635{
636	struct mtd_info *mtd = nand_to_mtd(chip);
637	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
638	unsigned long ecc = readl(info->regs + S3C2412_NFMECC0);
639
640	ecc_code[0] = ecc;
641	ecc_code[1] = ecc >> 8;
642	ecc_code[2] = ecc >> 16;
643
644	pr_debug("%s: returning ecc %*phN\n", __func__, 3, ecc_code);
645
646	return 0;
647}
648
649static int s3c2440_nand_calculate_ecc(struct nand_chip *chip,
650				      const u_char *dat, u_char *ecc_code)
651{
652	struct mtd_info *mtd = nand_to_mtd(chip);
653	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
654	unsigned long ecc = readl(info->regs + S3C2440_NFMECC0);
655
656	ecc_code[0] = ecc;
657	ecc_code[1] = ecc >> 8;
658	ecc_code[2] = ecc >> 16;
659
660	pr_debug("%s: returning ecc %06lx\n", __func__, ecc & 0xffffff);
661
662	return 0;
663}
664
665/* over-ride the standard functions for a little more speed. We can
666 * use read/write block to move the data buffers to/from the controller
667*/
668
669static void s3c2410_nand_read_buf(struct nand_chip *this, u_char *buf, int len)
670{
671	readsb(this->legacy.IO_ADDR_R, buf, len);
672}
673
674static void s3c2440_nand_read_buf(struct nand_chip *this, u_char *buf, int len)
675{
676	struct mtd_info *mtd = nand_to_mtd(this);
677	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
678
679	readsl(info->regs + S3C2440_NFDATA, buf, len >> 2);
680
681	/* cleanup if we've got less than a word to do */
682	if (len & 3) {
683		buf += len & ~3;
684
685		for (; len & 3; len--)
686			*buf++ = readb(info->regs + S3C2440_NFDATA);
687	}
688}
689
690static void s3c2410_nand_write_buf(struct nand_chip *this, const u_char *buf,
691				   int len)
692{
693	writesb(this->legacy.IO_ADDR_W, buf, len);
694}
695
696static void s3c2440_nand_write_buf(struct nand_chip *this, const u_char *buf,
697				   int len)
698{
699	struct mtd_info *mtd = nand_to_mtd(this);
700	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
701
702	writesl(info->regs + S3C2440_NFDATA, buf, len >> 2);
703
704	/* cleanup any fractional write */
705	if (len & 3) {
706		buf += len & ~3;
707
708		for (; len & 3; len--, buf++)
709			writeb(*buf, info->regs + S3C2440_NFDATA);
710	}
711}
712
713/* cpufreq driver support */
714
715#ifdef CONFIG_ARM_S3C24XX_CPUFREQ
716
717static int s3c2410_nand_cpufreq_transition(struct notifier_block *nb,
718					  unsigned long val, void *data)
719{
720	struct s3c2410_nand_info *info;
721	unsigned long newclk;
722
723	info = container_of(nb, struct s3c2410_nand_info, freq_transition);
724	newclk = clk_get_rate(info->clk);
725
726	if ((val == CPUFREQ_POSTCHANGE && newclk < info->clk_rate) ||
727	    (val == CPUFREQ_PRECHANGE && newclk > info->clk_rate)) {
728		s3c2410_nand_setrate(info);
729	}
730
731	return 0;
732}
733
734static inline int s3c2410_nand_cpufreq_register(struct s3c2410_nand_info *info)
735{
736	info->freq_transition.notifier_call = s3c2410_nand_cpufreq_transition;
737
738	return cpufreq_register_notifier(&info->freq_transition,
739					 CPUFREQ_TRANSITION_NOTIFIER);
740}
741
742static inline void
743s3c2410_nand_cpufreq_deregister(struct s3c2410_nand_info *info)
744{
745	cpufreq_unregister_notifier(&info->freq_transition,
746				    CPUFREQ_TRANSITION_NOTIFIER);
747}
748
749#else
750static inline int s3c2410_nand_cpufreq_register(struct s3c2410_nand_info *info)
751{
752	return 0;
753}
754
755static inline void
756s3c2410_nand_cpufreq_deregister(struct s3c2410_nand_info *info)
757{
758}
759#endif
760
761/* device management functions */
762
763static int s3c24xx_nand_remove(struct platform_device *pdev)
764{
765	struct s3c2410_nand_info *info = to_nand_info(pdev);
766
767	if (info == NULL)
768		return 0;
769
770	s3c2410_nand_cpufreq_deregister(info);
771
772	/* Release all our mtds  and their partitions, then go through
773	 * freeing the resources used
774	 */
775
776	if (info->mtds != NULL) {
777		struct s3c2410_nand_mtd *ptr = info->mtds;
778		int mtdno;
779
780		for (mtdno = 0; mtdno < info->mtd_count; mtdno++, ptr++) {
781			pr_debug("releasing mtd %d (%p)\n", mtdno, ptr);
782			WARN_ON(mtd_device_unregister(nand_to_mtd(&ptr->chip)));
783			nand_cleanup(&ptr->chip);
784		}
785	}
786
787	/* free the common resources */
788
789	if (!IS_ERR(info->clk))
790		s3c2410_nand_clk_set_state(info, CLOCK_DISABLE);
791
792	return 0;
793}
794
795static int s3c2410_nand_add_partition(struct s3c2410_nand_info *info,
796				      struct s3c2410_nand_mtd *mtd,
797				      struct s3c2410_nand_set *set)
798{
799	if (set) {
800		struct mtd_info *mtdinfo = nand_to_mtd(&mtd->chip);
801
802		mtdinfo->name = set->name;
803
804		return mtd_device_register(mtdinfo, set->partitions,
805					   set->nr_partitions);
806	}
807
808	return -ENODEV;
809}
810
811static int s3c2410_nand_setup_interface(struct nand_chip *chip, int csline,
812					const struct nand_interface_config *conf)
813{
814	struct mtd_info *mtd = nand_to_mtd(chip);
815	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
816	struct s3c2410_platform_nand *pdata = info->platform;
817	const struct nand_sdr_timings *timings;
818	int tacls;
819
820	timings = nand_get_sdr_timings(conf);
821	if (IS_ERR(timings))
822		return -ENOTSUPP;
823
824	tacls = timings->tCLS_min - timings->tWP_min;
825	if (tacls < 0)
826		tacls = 0;
827
828	pdata->tacls  = DIV_ROUND_UP(tacls, 1000);
829	pdata->twrph0 = DIV_ROUND_UP(timings->tWP_min, 1000);
830	pdata->twrph1 = DIV_ROUND_UP(timings->tCLH_min, 1000);
831
832	return s3c2410_nand_setrate(info);
833}
834
835/**
836 * s3c2410_nand_init_chip - initialise a single instance of an chip
837 * @info: The base NAND controller the chip is on.
838 * @nmtd: The new controller MTD instance to fill in.
839 * @set: The information passed from the board specific platform data.
840 *
841 * Initialise the given @nmtd from the information in @info and @set. This
842 * readies the structure for use with the MTD layer functions by ensuring
843 * all pointers are setup and the necessary control routines selected.
844 */
845static void s3c2410_nand_init_chip(struct s3c2410_nand_info *info,
846				   struct s3c2410_nand_mtd *nmtd,
847				   struct s3c2410_nand_set *set)
848{
849	struct device_node *np = info->device->of_node;
850	struct nand_chip *chip = &nmtd->chip;
851	void __iomem *regs = info->regs;
852
853	nand_set_flash_node(chip, set->of_node);
854
855	chip->legacy.write_buf    = s3c2410_nand_write_buf;
856	chip->legacy.read_buf     = s3c2410_nand_read_buf;
857	chip->legacy.select_chip  = s3c2410_nand_select_chip;
858	chip->legacy.chip_delay   = 50;
859	nand_set_controller_data(chip, nmtd);
860	chip->options	   = set->options;
861	chip->controller   = &info->controller;
862
863	/*
864	 * let's keep behavior unchanged for legacy boards booting via pdata and
865	 * auto-detect timings only when booting with a device tree.
866	 */
867	if (!np)
868		chip->options |= NAND_KEEP_TIMINGS;
869
870	switch (info->cpu_type) {
871	case TYPE_S3C2410:
872		chip->legacy.IO_ADDR_W = regs + S3C2410_NFDATA;
873		info->sel_reg   = regs + S3C2410_NFCONF;
874		info->sel_bit	= S3C2410_NFCONF_nFCE;
875		chip->legacy.cmd_ctrl  = s3c2410_nand_hwcontrol;
876		chip->legacy.dev_ready = s3c2410_nand_devready;
877		break;
878
879	case TYPE_S3C2440:
880		chip->legacy.IO_ADDR_W = regs + S3C2440_NFDATA;
881		info->sel_reg   = regs + S3C2440_NFCONT;
882		info->sel_bit	= S3C2440_NFCONT_nFCE;
883		chip->legacy.cmd_ctrl  = s3c2440_nand_hwcontrol;
884		chip->legacy.dev_ready = s3c2440_nand_devready;
885		chip->legacy.read_buf  = s3c2440_nand_read_buf;
886		chip->legacy.write_buf	= s3c2440_nand_write_buf;
887		break;
888
889	case TYPE_S3C2412:
890		chip->legacy.IO_ADDR_W = regs + S3C2440_NFDATA;
891		info->sel_reg   = regs + S3C2440_NFCONT;
892		info->sel_bit	= S3C2412_NFCONT_nFCE0;
893		chip->legacy.cmd_ctrl  = s3c2440_nand_hwcontrol;
894		chip->legacy.dev_ready = s3c2412_nand_devready;
895
896		if (readl(regs + S3C2410_NFCONF) & S3C2412_NFCONF_NANDBOOT)
897			dev_info(info->device, "System booted from NAND\n");
898
899		break;
900	}
901
902	chip->legacy.IO_ADDR_R = chip->legacy.IO_ADDR_W;
903
904	nmtd->info	   = info;
905	nmtd->set	   = set;
906
907	chip->ecc.engine_type = info->platform->engine_type;
908
909	/*
910	 * If you use u-boot BBT creation code, specifying this flag will
911	 * let the kernel fish out the BBT from the NAND.
912	 */
913	if (set->flash_bbt)
914		chip->bbt_options |= NAND_BBT_USE_FLASH;
915}
916
917/**
918 * s3c2410_nand_attach_chip - Init the ECC engine after NAND scan
919 * @chip: The NAND chip
920 *
921 * This hook is called by the core after the identification of the NAND chip,
922 * once the relevant per-chip information is up to date.. This call ensure that
923 * we update the internal state accordingly.
924 *
925 * The internal state is currently limited to the ECC state information.
926*/
927static int s3c2410_nand_attach_chip(struct nand_chip *chip)
928{
929	struct mtd_info *mtd = nand_to_mtd(chip);
930	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
931
932	switch (chip->ecc.engine_type) {
933
934	case NAND_ECC_ENGINE_TYPE_NONE:
935		dev_info(info->device, "ECC disabled\n");
936		break;
937
938	case NAND_ECC_ENGINE_TYPE_SOFT:
939		/*
940		 * This driver expects Hamming based ECC when engine_type is set
941		 * to NAND_ECC_ENGINE_TYPE_SOFT. Force ecc.algo to
942		 * NAND_ECC_ALGO_HAMMING to avoid adding an extra ecc_algo field
943		 * to s3c2410_platform_nand.
944		 */
945		chip->ecc.algo = NAND_ECC_ALGO_HAMMING;
946		dev_info(info->device, "soft ECC\n");
947		break;
948
949	case NAND_ECC_ENGINE_TYPE_ON_HOST:
950		chip->ecc.calculate = s3c2410_nand_calculate_ecc;
951		chip->ecc.correct   = s3c2410_nand_correct_data;
952		chip->ecc.strength  = 1;
953
954		switch (info->cpu_type) {
955		case TYPE_S3C2410:
956			chip->ecc.hwctl	    = s3c2410_nand_enable_hwecc;
957			chip->ecc.calculate = s3c2410_nand_calculate_ecc;
958			break;
959
960		case TYPE_S3C2412:
961			chip->ecc.hwctl     = s3c2412_nand_enable_hwecc;
962			chip->ecc.calculate = s3c2412_nand_calculate_ecc;
963			break;
964
965		case TYPE_S3C2440:
966			chip->ecc.hwctl     = s3c2440_nand_enable_hwecc;
967			chip->ecc.calculate = s3c2440_nand_calculate_ecc;
968			break;
969		}
970
971		dev_dbg(info->device, "chip %p => page shift %d\n",
972			chip, chip->page_shift);
973
974		/* change the behaviour depending on whether we are using
975		 * the large or small page nand device */
976		if (chip->page_shift > 10) {
977			chip->ecc.size	    = 256;
978			chip->ecc.bytes	    = 3;
979		} else {
980			chip->ecc.size	    = 512;
981			chip->ecc.bytes	    = 3;
982			mtd_set_ooblayout(nand_to_mtd(chip),
983					  &s3c2410_ooblayout_ops);
984		}
985
986		dev_info(info->device, "hardware ECC\n");
987		break;
988
989	default:
990		dev_err(info->device, "invalid ECC mode!\n");
991		return -EINVAL;
992	}
993
994	if (chip->bbt_options & NAND_BBT_USE_FLASH)
995		chip->options |= NAND_SKIP_BBTSCAN;
996
997	return 0;
998}
999
1000static const struct nand_controller_ops s3c24xx_nand_controller_ops = {
1001	.attach_chip = s3c2410_nand_attach_chip,
1002	.setup_interface = s3c2410_nand_setup_interface,
1003};
1004
1005static const struct of_device_id s3c24xx_nand_dt_ids[] = {
1006	{
1007		.compatible = "samsung,s3c2410-nand",
1008		.data = &s3c2410_nand_devtype_data,
1009	}, {
1010		/* also compatible with s3c6400 */
1011		.compatible = "samsung,s3c2412-nand",
1012		.data = &s3c2412_nand_devtype_data,
1013	}, {
1014		.compatible = "samsung,s3c2440-nand",
1015		.data = &s3c2440_nand_devtype_data,
1016	},
1017	{ /* sentinel */ }
1018};
1019MODULE_DEVICE_TABLE(of, s3c24xx_nand_dt_ids);
1020
1021static int s3c24xx_nand_probe_dt(struct platform_device *pdev)
1022{
1023	const struct s3c24XX_nand_devtype_data *devtype_data;
1024	struct s3c2410_platform_nand *pdata;
1025	struct s3c2410_nand_info *info = platform_get_drvdata(pdev);
1026	struct device_node *np = pdev->dev.of_node, *child;
1027	struct s3c2410_nand_set *sets;
1028
1029	devtype_data = of_device_get_match_data(&pdev->dev);
1030	if (!devtype_data)
1031		return -ENODEV;
1032
1033	info->cpu_type = devtype_data->type;
1034
1035	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
1036	if (!pdata)
1037		return -ENOMEM;
1038
1039	pdev->dev.platform_data = pdata;
1040
1041	pdata->nr_sets = of_get_child_count(np);
1042	if (!pdata->nr_sets)
1043		return 0;
1044
1045	sets = devm_kcalloc(&pdev->dev, pdata->nr_sets, sizeof(*sets),
1046			    GFP_KERNEL);
1047	if (!sets)
1048		return -ENOMEM;
1049
1050	pdata->sets = sets;
1051
1052	for_each_available_child_of_node(np, child) {
1053		sets->name = (char *)child->name;
1054		sets->of_node = child;
1055		sets->nr_chips = 1;
1056
1057		of_node_get(child);
1058
1059		sets++;
1060	}
1061
1062	return 0;
1063}
1064
1065static int s3c24xx_nand_probe_pdata(struct platform_device *pdev)
1066{
1067	struct s3c2410_nand_info *info = platform_get_drvdata(pdev);
1068
1069	info->cpu_type = platform_get_device_id(pdev)->driver_data;
1070
1071	return 0;
1072}
1073
1074/* s3c24xx_nand_probe
1075 *
1076 * called by device layer when it finds a device matching
1077 * one our driver can handled. This code checks to see if
1078 * it can allocate all necessary resources then calls the
1079 * nand layer to look for devices
1080*/
1081static int s3c24xx_nand_probe(struct platform_device *pdev)
1082{
1083	struct s3c2410_platform_nand *plat;
1084	struct s3c2410_nand_info *info;
1085	struct s3c2410_nand_mtd *nmtd;
1086	struct s3c2410_nand_set *sets;
1087	struct resource *res;
1088	int err = 0;
1089	int size;
1090	int nr_sets;
1091	int setno;
1092
1093	info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
1094	if (info == NULL) {
1095		err = -ENOMEM;
1096		goto exit_error;
1097	}
1098
1099	platform_set_drvdata(pdev, info);
1100
1101	nand_controller_init(&info->controller);
1102	info->controller.ops = &s3c24xx_nand_controller_ops;
1103
1104	/* get the clock source and enable it */
1105
1106	info->clk = devm_clk_get(&pdev->dev, "nand");
1107	if (IS_ERR(info->clk)) {
1108		dev_err(&pdev->dev, "failed to get clock\n");
1109		err = -ENOENT;
1110		goto exit_error;
1111	}
1112
1113	s3c2410_nand_clk_set_state(info, CLOCK_ENABLE);
1114
1115	if (pdev->dev.of_node)
1116		err = s3c24xx_nand_probe_dt(pdev);
1117	else
1118		err = s3c24xx_nand_probe_pdata(pdev);
1119
1120	if (err)
1121		goto exit_error;
1122
1123	plat = to_nand_plat(pdev);
1124
1125	/* allocate and map the resource */
1126
1127	/* currently we assume we have the one resource */
1128	res = pdev->resource;
1129	size = resource_size(res);
1130
1131	info->device	= &pdev->dev;
1132	info->platform	= plat;
1133
1134	info->regs = devm_ioremap_resource(&pdev->dev, res);
1135	if (IS_ERR(info->regs)) {
1136		err = PTR_ERR(info->regs);
1137		goto exit_error;
1138	}
1139
1140	dev_dbg(&pdev->dev, "mapped registers at %p\n", info->regs);
1141
1142	if (!plat->sets || plat->nr_sets < 1) {
1143		err = -EINVAL;
1144		goto exit_error;
1145	}
1146
1147	sets = plat->sets;
1148	nr_sets = plat->nr_sets;
1149
1150	info->mtd_count = nr_sets;
1151
1152	/* allocate our information */
1153
1154	size = nr_sets * sizeof(*info->mtds);
1155	info->mtds = devm_kzalloc(&pdev->dev, size, GFP_KERNEL);
1156	if (info->mtds == NULL) {
1157		err = -ENOMEM;
1158		goto exit_error;
1159	}
1160
1161	/* initialise all possible chips */
1162
1163	nmtd = info->mtds;
1164
1165	for (setno = 0; setno < nr_sets; setno++, nmtd++, sets++) {
1166		struct mtd_info *mtd = nand_to_mtd(&nmtd->chip);
1167
1168		pr_debug("initialising set %d (%p, info %p)\n",
1169			 setno, nmtd, info);
1170
1171		mtd->dev.parent = &pdev->dev;
1172		s3c2410_nand_init_chip(info, nmtd, sets);
1173
1174		err = nand_scan(&nmtd->chip, sets ? sets->nr_chips : 1);
1175		if (err)
1176			goto exit_error;
1177
1178		s3c2410_nand_add_partition(info, nmtd, sets);
1179	}
1180
1181	/* initialise the hardware */
1182	err = s3c2410_nand_inithw(info);
1183	if (err != 0)
1184		goto exit_error;
1185
1186	err = s3c2410_nand_cpufreq_register(info);
1187	if (err < 0) {
1188		dev_err(&pdev->dev, "failed to init cpufreq support\n");
1189		goto exit_error;
1190	}
1191
1192	if (allow_clk_suspend(info)) {
1193		dev_info(&pdev->dev, "clock idle support enabled\n");
1194		s3c2410_nand_clk_set_state(info, CLOCK_SUSPEND);
1195	}
1196
1197	return 0;
1198
1199 exit_error:
1200	s3c24xx_nand_remove(pdev);
1201
1202	if (err == 0)
1203		err = -EINVAL;
1204	return err;
1205}
1206
1207/* PM Support */
1208#ifdef CONFIG_PM
1209
1210static int s3c24xx_nand_suspend(struct platform_device *dev, pm_message_t pm)
1211{
1212	struct s3c2410_nand_info *info = platform_get_drvdata(dev);
1213
1214	if (info) {
1215		info->save_sel = readl(info->sel_reg);
1216
1217		/* For the moment, we must ensure nFCE is high during
1218		 * the time we are suspended. This really should be
1219		 * handled by suspending the MTDs we are using, but
1220		 * that is currently not the case. */
1221
1222		writel(info->save_sel | info->sel_bit, info->sel_reg);
1223
1224		s3c2410_nand_clk_set_state(info, CLOCK_DISABLE);
1225	}
1226
1227	return 0;
1228}
1229
1230static int s3c24xx_nand_resume(struct platform_device *dev)
1231{
1232	struct s3c2410_nand_info *info = platform_get_drvdata(dev);
1233	unsigned long sel;
1234
1235	if (info) {
1236		s3c2410_nand_clk_set_state(info, CLOCK_ENABLE);
1237		s3c2410_nand_inithw(info);
1238
1239		/* Restore the state of the nFCE line. */
1240
1241		sel = readl(info->sel_reg);
1242		sel &= ~info->sel_bit;
1243		sel |= info->save_sel & info->sel_bit;
1244		writel(sel, info->sel_reg);
1245
1246		s3c2410_nand_clk_set_state(info, CLOCK_SUSPEND);
1247	}
1248
1249	return 0;
1250}
1251
1252#else
1253#define s3c24xx_nand_suspend NULL
1254#define s3c24xx_nand_resume NULL
1255#endif
1256
1257/* driver device registration */
1258
1259static const struct platform_device_id s3c24xx_driver_ids[] = {
1260	{
1261		.name		= "s3c2410-nand",
1262		.driver_data	= TYPE_S3C2410,
1263	}, {
1264		.name		= "s3c2440-nand",
1265		.driver_data	= TYPE_S3C2440,
1266	}, {
1267		.name		= "s3c2412-nand",
1268		.driver_data	= TYPE_S3C2412,
1269	}, {
1270		.name		= "s3c6400-nand",
1271		.driver_data	= TYPE_S3C2412, /* compatible with 2412 */
1272	},
1273	{ }
1274};
1275
1276MODULE_DEVICE_TABLE(platform, s3c24xx_driver_ids);
1277
1278static struct platform_driver s3c24xx_nand_driver = {
1279	.probe		= s3c24xx_nand_probe,
1280	.remove		= s3c24xx_nand_remove,
1281	.suspend	= s3c24xx_nand_suspend,
1282	.resume		= s3c24xx_nand_resume,
1283	.id_table	= s3c24xx_driver_ids,
1284	.driver		= {
1285		.name	= "s3c24xx-nand",
1286		.of_match_table = s3c24xx_nand_dt_ids,
1287	},
1288};
1289
1290module_platform_driver(s3c24xx_nand_driver);
1291
1292MODULE_LICENSE("GPL");
1293MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
1294MODULE_DESCRIPTION("S3C24XX MTD NAND driver");
1295