1/* linux/drivers/mtd/nand/s3c2410.c
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 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17 * GNU General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
22*/
23
24#define pr_fmt(fmt) "nand-s3c2410: " fmt
25
26#ifdef CONFIG_MTD_NAND_S3C2410_DEBUG
27#define DEBUG
28#endif
29
30#include <linux/module.h>
31#include <linux/types.h>
32#include <linux/kernel.h>
33#include <linux/string.h>
34#include <linux/io.h>
35#include <linux/ioport.h>
36#include <linux/platform_device.h>
37#include <linux/delay.h>
38#include <linux/err.h>
39#include <linux/slab.h>
40#include <linux/clk.h>
41#include <linux/cpufreq.h>
42
43#include <linux/mtd/mtd.h>
44#include <linux/mtd/nand.h>
45#include <linux/mtd/nand_ecc.h>
46#include <linux/mtd/partitions.h>
47
48#include <linux/platform_data/mtd-nand-s3c2410.h>
49
50#define S3C2410_NFREG(x) (x)
51
52#define S3C2410_NFCONF		S3C2410_NFREG(0x00)
53#define S3C2410_NFCMD		S3C2410_NFREG(0x04)
54#define S3C2410_NFADDR		S3C2410_NFREG(0x08)
55#define S3C2410_NFDATA		S3C2410_NFREG(0x0C)
56#define S3C2410_NFSTAT		S3C2410_NFREG(0x10)
57#define S3C2410_NFECC		S3C2410_NFREG(0x14)
58#define S3C2440_NFCONT		S3C2410_NFREG(0x04)
59#define S3C2440_NFCMD		S3C2410_NFREG(0x08)
60#define S3C2440_NFADDR		S3C2410_NFREG(0x0C)
61#define S3C2440_NFDATA		S3C2410_NFREG(0x10)
62#define S3C2440_NFSTAT		S3C2410_NFREG(0x20)
63#define S3C2440_NFMECC0		S3C2410_NFREG(0x2C)
64#define S3C2412_NFSTAT		S3C2410_NFREG(0x28)
65#define S3C2412_NFMECC0		S3C2410_NFREG(0x34)
66#define S3C2410_NFCONF_EN		(1<<15)
67#define S3C2410_NFCONF_INITECC		(1<<12)
68#define S3C2410_NFCONF_nFCE		(1<<11)
69#define S3C2410_NFCONF_TACLS(x)		((x)<<8)
70#define S3C2410_NFCONF_TWRPH0(x)	((x)<<4)
71#define S3C2410_NFCONF_TWRPH1(x)	((x)<<0)
72#define S3C2410_NFSTAT_BUSY		(1<<0)
73#define S3C2440_NFCONF_TACLS(x)		((x)<<12)
74#define S3C2440_NFCONF_TWRPH0(x)	((x)<<8)
75#define S3C2440_NFCONF_TWRPH1(x)	((x)<<4)
76#define S3C2440_NFCONT_INITECC		(1<<4)
77#define S3C2440_NFCONT_nFCE		(1<<1)
78#define S3C2440_NFCONT_ENABLE		(1<<0)
79#define S3C2440_NFSTAT_READY		(1<<0)
80#define S3C2412_NFCONF_NANDBOOT		(1<<31)
81#define S3C2412_NFCONT_INIT_MAIN_ECC	(1<<5)
82#define S3C2412_NFCONT_nFCE0		(1<<1)
83#define S3C2412_NFSTAT_READY		(1<<0)
84
85/* new oob placement block for use with hardware ecc generation
86 */
87
88static struct nand_ecclayout nand_hw_eccoob = {
89	.eccbytes = 3,
90	.eccpos = {0, 1, 2},
91	.oobfree = {{8, 8}}
92};
93
94/* controller and mtd information */
95
96struct s3c2410_nand_info;
97
98/**
99 * struct s3c2410_nand_mtd - driver MTD structure
100 * @mtd: The MTD instance to pass to the MTD layer.
101 * @chip: The NAND chip information.
102 * @set: The platform information supplied for this set of NAND chips.
103 * @info: Link back to the hardware information.
104 * @scan_res: The result from calling nand_scan_ident().
105*/
106struct s3c2410_nand_mtd {
107	struct mtd_info			mtd;
108	struct nand_chip		chip;
109	struct s3c2410_nand_set		*set;
110	struct s3c2410_nand_info	*info;
111	int				scan_res;
112};
113
114enum s3c_cpu_type {
115	TYPE_S3C2410,
116	TYPE_S3C2412,
117	TYPE_S3C2440,
118};
119
120enum s3c_nand_clk_state {
121	CLOCK_DISABLE	= 0,
122	CLOCK_ENABLE,
123	CLOCK_SUSPEND,
124};
125
126/* overview of the s3c2410 nand state */
127
128/**
129 * struct s3c2410_nand_info - NAND controller state.
130 * @mtds: An array of MTD instances on this controoler.
131 * @platform: The platform data for this board.
132 * @device: The platform device we bound to.
133 * @clk: The clock resource for this controller.
134 * @regs: The area mapped for the hardware registers.
135 * @sel_reg: Pointer to the register controlling the NAND selection.
136 * @sel_bit: The bit in @sel_reg to select the NAND chip.
137 * @mtd_count: The number of MTDs created from this controller.
138 * @save_sel: The contents of @sel_reg to be saved over suspend.
139 * @clk_rate: The clock rate from @clk.
140 * @clk_state: The current clock state.
141 * @cpu_type: The exact type of this controller.
142 */
143struct s3c2410_nand_info {
144	/* mtd info */
145	struct nand_hw_control		controller;
146	struct s3c2410_nand_mtd		*mtds;
147	struct s3c2410_platform_nand	*platform;
148
149	/* device info */
150	struct device			*device;
151	struct clk			*clk;
152	void __iomem			*regs;
153	void __iomem			*sel_reg;
154	int				sel_bit;
155	int				mtd_count;
156	unsigned long			save_sel;
157	unsigned long			clk_rate;
158	enum s3c_nand_clk_state		clk_state;
159
160	enum s3c_cpu_type		cpu_type;
161
162#ifdef CONFIG_CPU_FREQ
163	struct notifier_block	freq_transition;
164#endif
165};
166
167/* conversion functions */
168
169static struct s3c2410_nand_mtd *s3c2410_nand_mtd_toours(struct mtd_info *mtd)
170{
171	return container_of(mtd, struct s3c2410_nand_mtd, mtd);
172}
173
174static struct s3c2410_nand_info *s3c2410_nand_mtd_toinfo(struct mtd_info *mtd)
175{
176	return s3c2410_nand_mtd_toours(mtd)->info;
177}
178
179static struct s3c2410_nand_info *to_nand_info(struct platform_device *dev)
180{
181	return platform_get_drvdata(dev);
182}
183
184static struct s3c2410_platform_nand *to_nand_plat(struct platform_device *dev)
185{
186	return dev_get_platdata(&dev->dev);
187}
188
189static inline int allow_clk_suspend(struct s3c2410_nand_info *info)
190{
191#ifdef CONFIG_MTD_NAND_S3C2410_CLKSTOP
192	return 1;
193#else
194	return 0;
195#endif
196}
197
198/**
199 * s3c2410_nand_clk_set_state - Enable, disable or suspend NAND clock.
200 * @info: The controller instance.
201 * @new_state: State to which clock should be set.
202 */
203static void s3c2410_nand_clk_set_state(struct s3c2410_nand_info *info,
204		enum s3c_nand_clk_state new_state)
205{
206	if (!allow_clk_suspend(info) && new_state == CLOCK_SUSPEND)
207		return;
208
209	if (info->clk_state == CLOCK_ENABLE) {
210		if (new_state != CLOCK_ENABLE)
211			clk_disable_unprepare(info->clk);
212	} else {
213		if (new_state == CLOCK_ENABLE)
214			clk_prepare_enable(info->clk);
215	}
216
217	info->clk_state = new_state;
218}
219
220/* timing calculations */
221
222#define NS_IN_KHZ 1000000
223
224/**
225 * s3c_nand_calc_rate - calculate timing data.
226 * @wanted: The cycle time in nanoseconds.
227 * @clk: The clock rate in kHz.
228 * @max: The maximum divider value.
229 *
230 * Calculate the timing value from the given parameters.
231 */
232static int s3c_nand_calc_rate(int wanted, unsigned long clk, int max)
233{
234	int result;
235
236	result = DIV_ROUND_UP((wanted * clk), NS_IN_KHZ);
237
238	pr_debug("result %d from %ld, %d\n", result, clk, wanted);
239
240	if (result > max) {
241		pr_err("%d ns is too big for current clock rate %ld\n",
242			wanted, clk);
243		return -1;
244	}
245
246	if (result < 1)
247		result = 1;
248
249	return result;
250}
251
252#define to_ns(ticks, clk) (((ticks) * NS_IN_KHZ) / (unsigned int)(clk))
253
254/* controller setup */
255
256/**
257 * s3c2410_nand_setrate - setup controller timing information.
258 * @info: The controller instance.
259 *
260 * Given the information supplied by the platform, calculate and set
261 * the necessary timing registers in the hardware to generate the
262 * necessary timing cycles to the hardware.
263 */
264static int s3c2410_nand_setrate(struct s3c2410_nand_info *info)
265{
266	struct s3c2410_platform_nand *plat = info->platform;
267	int tacls_max = (info->cpu_type == TYPE_S3C2412) ? 8 : 4;
268	int tacls, twrph0, twrph1;
269	unsigned long clkrate = clk_get_rate(info->clk);
270	unsigned long uninitialized_var(set), cfg, uninitialized_var(mask);
271	unsigned long flags;
272
273	/* calculate the timing information for the controller */
274
275	info->clk_rate = clkrate;
276	clkrate /= 1000;	/* turn clock into kHz for ease of use */
277
278	if (plat != NULL) {
279		tacls = s3c_nand_calc_rate(plat->tacls, clkrate, tacls_max);
280		twrph0 = s3c_nand_calc_rate(plat->twrph0, clkrate, 8);
281		twrph1 = s3c_nand_calc_rate(plat->twrph1, clkrate, 8);
282	} else {
283		/* default timings */
284		tacls = tacls_max;
285		twrph0 = 8;
286		twrph1 = 8;
287	}
288
289	if (tacls < 0 || twrph0 < 0 || twrph1 < 0) {
290		dev_err(info->device, "cannot get suitable timings\n");
291		return -EINVAL;
292	}
293
294	dev_info(info->device, "Tacls=%d, %dns Twrph0=%d %dns, Twrph1=%d %dns\n",
295		tacls, to_ns(tacls, clkrate), twrph0, to_ns(twrph0, clkrate),
296						twrph1, to_ns(twrph1, clkrate));
297
298	switch (info->cpu_type) {
299	case TYPE_S3C2410:
300		mask = (S3C2410_NFCONF_TACLS(3) |
301			S3C2410_NFCONF_TWRPH0(7) |
302			S3C2410_NFCONF_TWRPH1(7));
303		set = S3C2410_NFCONF_EN;
304		set |= S3C2410_NFCONF_TACLS(tacls - 1);
305		set |= S3C2410_NFCONF_TWRPH0(twrph0 - 1);
306		set |= S3C2410_NFCONF_TWRPH1(twrph1 - 1);
307		break;
308
309	case TYPE_S3C2440:
310	case TYPE_S3C2412:
311		mask = (S3C2440_NFCONF_TACLS(tacls_max - 1) |
312			S3C2440_NFCONF_TWRPH0(7) |
313			S3C2440_NFCONF_TWRPH1(7));
314
315		set = S3C2440_NFCONF_TACLS(tacls - 1);
316		set |= S3C2440_NFCONF_TWRPH0(twrph0 - 1);
317		set |= S3C2440_NFCONF_TWRPH1(twrph1 - 1);
318		break;
319
320	default:
321		BUG();
322	}
323
324	local_irq_save(flags);
325
326	cfg = readl(info->regs + S3C2410_NFCONF);
327	cfg &= ~mask;
328	cfg |= set;
329	writel(cfg, info->regs + S3C2410_NFCONF);
330
331	local_irq_restore(flags);
332
333	dev_dbg(info->device, "NF_CONF is 0x%lx\n", cfg);
334
335	return 0;
336}
337
338/**
339 * s3c2410_nand_inithw - basic hardware initialisation
340 * @info: The hardware state.
341 *
342 * Do the basic initialisation of the hardware, using s3c2410_nand_setrate()
343 * to setup the hardware access speeds and set the controller to be enabled.
344*/
345static int s3c2410_nand_inithw(struct s3c2410_nand_info *info)
346{
347	int ret;
348
349	ret = s3c2410_nand_setrate(info);
350	if (ret < 0)
351		return ret;
352
353	switch (info->cpu_type) {
354	case TYPE_S3C2410:
355	default:
356		break;
357
358	case TYPE_S3C2440:
359	case TYPE_S3C2412:
360		/* enable the controller and de-assert nFCE */
361
362		writel(S3C2440_NFCONT_ENABLE, info->regs + S3C2440_NFCONT);
363	}
364
365	return 0;
366}
367
368/**
369 * s3c2410_nand_select_chip - select the given nand chip
370 * @mtd: The MTD instance for this chip.
371 * @chip: The chip number.
372 *
373 * This is called by the MTD layer to either select a given chip for the
374 * @mtd instance, or to indicate that the access has finished and the
375 * chip can be de-selected.
376 *
377 * The routine ensures that the nFCE line is correctly setup, and any
378 * platform specific selection code is called to route nFCE to the specific
379 * chip.
380 */
381static void s3c2410_nand_select_chip(struct mtd_info *mtd, int chip)
382{
383	struct s3c2410_nand_info *info;
384	struct s3c2410_nand_mtd *nmtd;
385	struct nand_chip *this = mtd->priv;
386	unsigned long cur;
387
388	nmtd = this->priv;
389	info = nmtd->info;
390
391	if (chip != -1)
392		s3c2410_nand_clk_set_state(info, CLOCK_ENABLE);
393
394	cur = readl(info->sel_reg);
395
396	if (chip == -1) {
397		cur |= info->sel_bit;
398	} else {
399		if (nmtd->set != NULL && chip > nmtd->set->nr_chips) {
400			dev_err(info->device, "invalid chip %d\n", chip);
401			return;
402		}
403
404		if (info->platform != NULL) {
405			if (info->platform->select_chip != NULL)
406				(info->platform->select_chip) (nmtd->set, chip);
407		}
408
409		cur &= ~info->sel_bit;
410	}
411
412	writel(cur, info->sel_reg);
413
414	if (chip == -1)
415		s3c2410_nand_clk_set_state(info, CLOCK_SUSPEND);
416}
417
418/* s3c2410_nand_hwcontrol
419 *
420 * Issue command and address cycles to the chip
421*/
422
423static void s3c2410_nand_hwcontrol(struct mtd_info *mtd, int cmd,
424				   unsigned int ctrl)
425{
426	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
427
428	if (cmd == NAND_CMD_NONE)
429		return;
430
431	if (ctrl & NAND_CLE)
432		writeb(cmd, info->regs + S3C2410_NFCMD);
433	else
434		writeb(cmd, info->regs + S3C2410_NFADDR);
435}
436
437/* command and control functions */
438
439static void s3c2440_nand_hwcontrol(struct mtd_info *mtd, int cmd,
440				   unsigned int ctrl)
441{
442	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
443
444	if (cmd == NAND_CMD_NONE)
445		return;
446
447	if (ctrl & NAND_CLE)
448		writeb(cmd, info->regs + S3C2440_NFCMD);
449	else
450		writeb(cmd, info->regs + S3C2440_NFADDR);
451}
452
453/* s3c2410_nand_devready()
454 *
455 * returns 0 if the nand is busy, 1 if it is ready
456*/
457
458static int s3c2410_nand_devready(struct mtd_info *mtd)
459{
460	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
461	return readb(info->regs + S3C2410_NFSTAT) & S3C2410_NFSTAT_BUSY;
462}
463
464static int s3c2440_nand_devready(struct mtd_info *mtd)
465{
466	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
467	return readb(info->regs + S3C2440_NFSTAT) & S3C2440_NFSTAT_READY;
468}
469
470static int s3c2412_nand_devready(struct mtd_info *mtd)
471{
472	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
473	return readb(info->regs + S3C2412_NFSTAT) & S3C2412_NFSTAT_READY;
474}
475
476/* ECC handling functions */
477
478#ifdef CONFIG_MTD_NAND_S3C2410_HWECC
479static int s3c2410_nand_correct_data(struct mtd_info *mtd, u_char *dat,
480				     u_char *read_ecc, u_char *calc_ecc)
481{
482	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
483	unsigned int diff0, diff1, diff2;
484	unsigned int bit, byte;
485
486	pr_debug("%s(%p,%p,%p,%p)\n", __func__, mtd, dat, read_ecc, calc_ecc);
487
488	diff0 = read_ecc[0] ^ calc_ecc[0];
489	diff1 = read_ecc[1] ^ calc_ecc[1];
490	diff2 = read_ecc[2] ^ calc_ecc[2];
491
492	pr_debug("%s: rd %*phN calc %*phN diff %02x%02x%02x\n",
493		 __func__, 3, read_ecc, 3, calc_ecc,
494		 diff0, diff1, diff2);
495
496	if (diff0 == 0 && diff1 == 0 && diff2 == 0)
497		return 0;		/* ECC is ok */
498
499	/* sometimes people do not think about using the ECC, so check
500	 * to see if we have an 0xff,0xff,0xff read ECC and then ignore
501	 * the error, on the assumption that this is an un-eccd page.
502	 */
503	if (read_ecc[0] == 0xff && read_ecc[1] == 0xff && read_ecc[2] == 0xff
504	    && info->platform->ignore_unset_ecc)
505		return 0;
506
507	/* Can we correct this ECC (ie, one row and column change).
508	 * Note, this is similar to the 256 error code on smartmedia */
509
510	if (((diff0 ^ (diff0 >> 1)) & 0x55) == 0x55 &&
511	    ((diff1 ^ (diff1 >> 1)) & 0x55) == 0x55 &&
512	    ((diff2 ^ (diff2 >> 1)) & 0x55) == 0x55) {
513		/* calculate the bit position of the error */
514
515		bit  = ((diff2 >> 3) & 1) |
516		       ((diff2 >> 4) & 2) |
517		       ((diff2 >> 5) & 4);
518
519		/* calculate the byte position of the error */
520
521		byte = ((diff2 << 7) & 0x100) |
522		       ((diff1 << 0) & 0x80)  |
523		       ((diff1 << 1) & 0x40)  |
524		       ((diff1 << 2) & 0x20)  |
525		       ((diff1 << 3) & 0x10)  |
526		       ((diff0 >> 4) & 0x08)  |
527		       ((diff0 >> 3) & 0x04)  |
528		       ((diff0 >> 2) & 0x02)  |
529		       ((diff0 >> 1) & 0x01);
530
531		dev_dbg(info->device, "correcting error bit %d, byte %d\n",
532			bit, byte);
533
534		dat[byte] ^= (1 << bit);
535		return 1;
536	}
537
538	/* if there is only one bit difference in the ECC, then
539	 * one of only a row or column parity has changed, which
540	 * means the error is most probably in the ECC itself */
541
542	diff0 |= (diff1 << 8);
543	diff0 |= (diff2 << 16);
544
545	if ((diff0 & ~(1<<fls(diff0))) == 0)
546		return 1;
547
548	return -1;
549}
550
551/* ECC functions
552 *
553 * These allow the s3c2410 and s3c2440 to use the controller's ECC
554 * generator block to ECC the data as it passes through]
555*/
556
557static void s3c2410_nand_enable_hwecc(struct mtd_info *mtd, int mode)
558{
559	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
560	unsigned long ctrl;
561
562	ctrl = readl(info->regs + S3C2410_NFCONF);
563	ctrl |= S3C2410_NFCONF_INITECC;
564	writel(ctrl, info->regs + S3C2410_NFCONF);
565}
566
567static void s3c2412_nand_enable_hwecc(struct mtd_info *mtd, int mode)
568{
569	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
570	unsigned long ctrl;
571
572	ctrl = readl(info->regs + S3C2440_NFCONT);
573	writel(ctrl | S3C2412_NFCONT_INIT_MAIN_ECC,
574	       info->regs + S3C2440_NFCONT);
575}
576
577static void s3c2440_nand_enable_hwecc(struct mtd_info *mtd, int mode)
578{
579	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
580	unsigned long ctrl;
581
582	ctrl = readl(info->regs + S3C2440_NFCONT);
583	writel(ctrl | S3C2440_NFCONT_INITECC, info->regs + S3C2440_NFCONT);
584}
585
586static int s3c2410_nand_calculate_ecc(struct mtd_info *mtd, const u_char *dat,
587				      u_char *ecc_code)
588{
589	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
590
591	ecc_code[0] = readb(info->regs + S3C2410_NFECC + 0);
592	ecc_code[1] = readb(info->regs + S3C2410_NFECC + 1);
593	ecc_code[2] = readb(info->regs + S3C2410_NFECC + 2);
594
595	pr_debug("%s: returning ecc %*phN\n", __func__, 3, ecc_code);
596
597	return 0;
598}
599
600static int s3c2412_nand_calculate_ecc(struct mtd_info *mtd, const u_char *dat,
601				      u_char *ecc_code)
602{
603	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
604	unsigned long ecc = readl(info->regs + S3C2412_NFMECC0);
605
606	ecc_code[0] = ecc;
607	ecc_code[1] = ecc >> 8;
608	ecc_code[2] = ecc >> 16;
609
610	pr_debug("%s: returning ecc %*phN\n", __func__, 3, ecc_code);
611
612	return 0;
613}
614
615static int s3c2440_nand_calculate_ecc(struct mtd_info *mtd, const u_char *dat,
616				      u_char *ecc_code)
617{
618	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
619	unsigned long ecc = readl(info->regs + S3C2440_NFMECC0);
620
621	ecc_code[0] = ecc;
622	ecc_code[1] = ecc >> 8;
623	ecc_code[2] = ecc >> 16;
624
625	pr_debug("%s: returning ecc %06lx\n", __func__, ecc & 0xffffff);
626
627	return 0;
628}
629#endif
630
631/* over-ride the standard functions for a little more speed. We can
632 * use read/write block to move the data buffers to/from the controller
633*/
634
635static void s3c2410_nand_read_buf(struct mtd_info *mtd, u_char *buf, int len)
636{
637	struct nand_chip *this = mtd->priv;
638	readsb(this->IO_ADDR_R, buf, len);
639}
640
641static void s3c2440_nand_read_buf(struct mtd_info *mtd, u_char *buf, int len)
642{
643	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
644
645	readsl(info->regs + S3C2440_NFDATA, buf, len >> 2);
646
647	/* cleanup if we've got less than a word to do */
648	if (len & 3) {
649		buf += len & ~3;
650
651		for (; len & 3; len--)
652			*buf++ = readb(info->regs + S3C2440_NFDATA);
653	}
654}
655
656static void s3c2410_nand_write_buf(struct mtd_info *mtd, const u_char *buf,
657				   int len)
658{
659	struct nand_chip *this = mtd->priv;
660	writesb(this->IO_ADDR_W, buf, len);
661}
662
663static void s3c2440_nand_write_buf(struct mtd_info *mtd, const u_char *buf,
664				   int len)
665{
666	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
667
668	writesl(info->regs + S3C2440_NFDATA, buf, len >> 2);
669
670	/* cleanup any fractional write */
671	if (len & 3) {
672		buf += len & ~3;
673
674		for (; len & 3; len--, buf++)
675			writeb(*buf, info->regs + S3C2440_NFDATA);
676	}
677}
678
679/* cpufreq driver support */
680
681#ifdef CONFIG_CPU_FREQ
682
683static int s3c2410_nand_cpufreq_transition(struct notifier_block *nb,
684					  unsigned long val, void *data)
685{
686	struct s3c2410_nand_info *info;
687	unsigned long newclk;
688
689	info = container_of(nb, struct s3c2410_nand_info, freq_transition);
690	newclk = clk_get_rate(info->clk);
691
692	if ((val == CPUFREQ_POSTCHANGE && newclk < info->clk_rate) ||
693	    (val == CPUFREQ_PRECHANGE && newclk > info->clk_rate)) {
694		s3c2410_nand_setrate(info);
695	}
696
697	return 0;
698}
699
700static inline int s3c2410_nand_cpufreq_register(struct s3c2410_nand_info *info)
701{
702	info->freq_transition.notifier_call = s3c2410_nand_cpufreq_transition;
703
704	return cpufreq_register_notifier(&info->freq_transition,
705					 CPUFREQ_TRANSITION_NOTIFIER);
706}
707
708static inline void
709s3c2410_nand_cpufreq_deregister(struct s3c2410_nand_info *info)
710{
711	cpufreq_unregister_notifier(&info->freq_transition,
712				    CPUFREQ_TRANSITION_NOTIFIER);
713}
714
715#else
716static inline int s3c2410_nand_cpufreq_register(struct s3c2410_nand_info *info)
717{
718	return 0;
719}
720
721static inline void
722s3c2410_nand_cpufreq_deregister(struct s3c2410_nand_info *info)
723{
724}
725#endif
726
727/* device management functions */
728
729static int s3c24xx_nand_remove(struct platform_device *pdev)
730{
731	struct s3c2410_nand_info *info = to_nand_info(pdev);
732
733	if (info == NULL)
734		return 0;
735
736	s3c2410_nand_cpufreq_deregister(info);
737
738	/* Release all our mtds  and their partitions, then go through
739	 * freeing the resources used
740	 */
741
742	if (info->mtds != NULL) {
743		struct s3c2410_nand_mtd *ptr = info->mtds;
744		int mtdno;
745
746		for (mtdno = 0; mtdno < info->mtd_count; mtdno++, ptr++) {
747			pr_debug("releasing mtd %d (%p)\n", mtdno, ptr);
748			nand_release(&ptr->mtd);
749		}
750	}
751
752	/* free the common resources */
753
754	if (!IS_ERR(info->clk))
755		s3c2410_nand_clk_set_state(info, CLOCK_DISABLE);
756
757	return 0;
758}
759
760static int s3c2410_nand_add_partition(struct s3c2410_nand_info *info,
761				      struct s3c2410_nand_mtd *mtd,
762				      struct s3c2410_nand_set *set)
763{
764	if (set) {
765		mtd->mtd.name = set->name;
766
767		return mtd_device_parse_register(&mtd->mtd, NULL, NULL,
768					 set->partitions, set->nr_partitions);
769	}
770
771	return -ENODEV;
772}
773
774/**
775 * s3c2410_nand_init_chip - initialise a single instance of an chip
776 * @info: The base NAND controller the chip is on.
777 * @nmtd: The new controller MTD instance to fill in.
778 * @set: The information passed from the board specific platform data.
779 *
780 * Initialise the given @nmtd from the information in @info and @set. This
781 * readies the structure for use with the MTD layer functions by ensuring
782 * all pointers are setup and the necessary control routines selected.
783 */
784static void s3c2410_nand_init_chip(struct s3c2410_nand_info *info,
785				   struct s3c2410_nand_mtd *nmtd,
786				   struct s3c2410_nand_set *set)
787{
788	struct nand_chip *chip = &nmtd->chip;
789	void __iomem *regs = info->regs;
790
791	chip->write_buf    = s3c2410_nand_write_buf;
792	chip->read_buf     = s3c2410_nand_read_buf;
793	chip->select_chip  = s3c2410_nand_select_chip;
794	chip->chip_delay   = 50;
795	chip->priv	   = nmtd;
796	chip->options	   = set->options;
797	chip->controller   = &info->controller;
798
799	switch (info->cpu_type) {
800	case TYPE_S3C2410:
801		chip->IO_ADDR_W = regs + S3C2410_NFDATA;
802		info->sel_reg   = regs + S3C2410_NFCONF;
803		info->sel_bit	= S3C2410_NFCONF_nFCE;
804		chip->cmd_ctrl  = s3c2410_nand_hwcontrol;
805		chip->dev_ready = s3c2410_nand_devready;
806		break;
807
808	case TYPE_S3C2440:
809		chip->IO_ADDR_W = regs + S3C2440_NFDATA;
810		info->sel_reg   = regs + S3C2440_NFCONT;
811		info->sel_bit	= S3C2440_NFCONT_nFCE;
812		chip->cmd_ctrl  = s3c2440_nand_hwcontrol;
813		chip->dev_ready = s3c2440_nand_devready;
814		chip->read_buf  = s3c2440_nand_read_buf;
815		chip->write_buf	= s3c2440_nand_write_buf;
816		break;
817
818	case TYPE_S3C2412:
819		chip->IO_ADDR_W = regs + S3C2440_NFDATA;
820		info->sel_reg   = regs + S3C2440_NFCONT;
821		info->sel_bit	= S3C2412_NFCONT_nFCE0;
822		chip->cmd_ctrl  = s3c2440_nand_hwcontrol;
823		chip->dev_ready = s3c2412_nand_devready;
824
825		if (readl(regs + S3C2410_NFCONF) & S3C2412_NFCONF_NANDBOOT)
826			dev_info(info->device, "System booted from NAND\n");
827
828		break;
829	}
830
831	chip->IO_ADDR_R = chip->IO_ADDR_W;
832
833	nmtd->info	   = info;
834	nmtd->mtd.priv	   = chip;
835	nmtd->mtd.owner    = THIS_MODULE;
836	nmtd->set	   = set;
837
838#ifdef CONFIG_MTD_NAND_S3C2410_HWECC
839	chip->ecc.calculate = s3c2410_nand_calculate_ecc;
840	chip->ecc.correct   = s3c2410_nand_correct_data;
841	chip->ecc.mode	    = NAND_ECC_HW;
842	chip->ecc.strength  = 1;
843
844	switch (info->cpu_type) {
845	case TYPE_S3C2410:
846		chip->ecc.hwctl	    = s3c2410_nand_enable_hwecc;
847		chip->ecc.calculate = s3c2410_nand_calculate_ecc;
848		break;
849
850	case TYPE_S3C2412:
851		chip->ecc.hwctl     = s3c2412_nand_enable_hwecc;
852		chip->ecc.calculate = s3c2412_nand_calculate_ecc;
853		break;
854
855	case TYPE_S3C2440:
856		chip->ecc.hwctl     = s3c2440_nand_enable_hwecc;
857		chip->ecc.calculate = s3c2440_nand_calculate_ecc;
858		break;
859	}
860#else
861	chip->ecc.mode	    = NAND_ECC_SOFT;
862#endif
863
864	if (set->ecc_layout != NULL)
865		chip->ecc.layout = set->ecc_layout;
866
867	if (set->disable_ecc)
868		chip->ecc.mode	= NAND_ECC_NONE;
869
870	switch (chip->ecc.mode) {
871	case NAND_ECC_NONE:
872		dev_info(info->device, "NAND ECC disabled\n");
873		break;
874	case NAND_ECC_SOFT:
875		dev_info(info->device, "NAND soft ECC\n");
876		break;
877	case NAND_ECC_HW:
878		dev_info(info->device, "NAND hardware ECC\n");
879		break;
880	default:
881		dev_info(info->device, "NAND ECC UNKNOWN\n");
882		break;
883	}
884
885	/* If you use u-boot BBT creation code, specifying this flag will
886	 * let the kernel fish out the BBT from the NAND, and also skip the
887	 * full NAND scan that can take 1/2s or so. Little things... */
888	if (set->flash_bbt) {
889		chip->bbt_options |= NAND_BBT_USE_FLASH;
890		chip->options |= NAND_SKIP_BBTSCAN;
891	}
892}
893
894/**
895 * s3c2410_nand_update_chip - post probe update
896 * @info: The controller instance.
897 * @nmtd: The driver version of the MTD instance.
898 *
899 * This routine is called after the chip probe has successfully completed
900 * and the relevant per-chip information updated. This call ensure that
901 * we update the internal state accordingly.
902 *
903 * The internal state is currently limited to the ECC state information.
904*/
905static void s3c2410_nand_update_chip(struct s3c2410_nand_info *info,
906				     struct s3c2410_nand_mtd *nmtd)
907{
908	struct nand_chip *chip = &nmtd->chip;
909
910	dev_dbg(info->device, "chip %p => page shift %d\n",
911		chip, chip->page_shift);
912
913	if (chip->ecc.mode != NAND_ECC_HW)
914		return;
915
916		/* change the behaviour depending on whether we are using
917		 * the large or small page nand device */
918
919	if (chip->page_shift > 10) {
920		chip->ecc.size	    = 256;
921		chip->ecc.bytes	    = 3;
922	} else {
923		chip->ecc.size	    = 512;
924		chip->ecc.bytes	    = 3;
925		chip->ecc.layout    = &nand_hw_eccoob;
926	}
927}
928
929/* s3c24xx_nand_probe
930 *
931 * called by device layer when it finds a device matching
932 * one our driver can handled. This code checks to see if
933 * it can allocate all necessary resources then calls the
934 * nand layer to look for devices
935*/
936static int s3c24xx_nand_probe(struct platform_device *pdev)
937{
938	struct s3c2410_platform_nand *plat = to_nand_plat(pdev);
939	enum s3c_cpu_type cpu_type;
940	struct s3c2410_nand_info *info;
941	struct s3c2410_nand_mtd *nmtd;
942	struct s3c2410_nand_set *sets;
943	struct resource *res;
944	int err = 0;
945	int size;
946	int nr_sets;
947	int setno;
948
949	cpu_type = platform_get_device_id(pdev)->driver_data;
950
951	info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
952	if (info == NULL) {
953		err = -ENOMEM;
954		goto exit_error;
955	}
956
957	platform_set_drvdata(pdev, info);
958
959	spin_lock_init(&info->controller.lock);
960	init_waitqueue_head(&info->controller.wq);
961
962	/* get the clock source and enable it */
963
964	info->clk = devm_clk_get(&pdev->dev, "nand");
965	if (IS_ERR(info->clk)) {
966		dev_err(&pdev->dev, "failed to get clock\n");
967		err = -ENOENT;
968		goto exit_error;
969	}
970
971	s3c2410_nand_clk_set_state(info, CLOCK_ENABLE);
972
973	/* allocate and map the resource */
974
975	/* currently we assume we have the one resource */
976	res = pdev->resource;
977	size = resource_size(res);
978
979	info->device	= &pdev->dev;
980	info->platform	= plat;
981	info->cpu_type	= cpu_type;
982
983	info->regs = devm_ioremap_resource(&pdev->dev, res);
984	if (IS_ERR(info->regs)) {
985		err = PTR_ERR(info->regs);
986		goto exit_error;
987	}
988
989	dev_dbg(&pdev->dev, "mapped registers at %p\n", info->regs);
990
991	/* initialise the hardware */
992
993	err = s3c2410_nand_inithw(info);
994	if (err != 0)
995		goto exit_error;
996
997	sets = (plat != NULL) ? plat->sets : NULL;
998	nr_sets = (plat != NULL) ? plat->nr_sets : 1;
999
1000	info->mtd_count = nr_sets;
1001
1002	/* allocate our information */
1003
1004	size = nr_sets * sizeof(*info->mtds);
1005	info->mtds = devm_kzalloc(&pdev->dev, size, GFP_KERNEL);
1006	if (info->mtds == NULL) {
1007		err = -ENOMEM;
1008		goto exit_error;
1009	}
1010
1011	/* initialise all possible chips */
1012
1013	nmtd = info->mtds;
1014
1015	for (setno = 0; setno < nr_sets; setno++, nmtd++) {
1016		pr_debug("initialising set %d (%p, info %p)\n",
1017			 setno, nmtd, info);
1018
1019		s3c2410_nand_init_chip(info, nmtd, sets);
1020
1021		nmtd->scan_res = nand_scan_ident(&nmtd->mtd,
1022						 (sets) ? sets->nr_chips : 1,
1023						 NULL);
1024
1025		if (nmtd->scan_res == 0) {
1026			s3c2410_nand_update_chip(info, nmtd);
1027			nand_scan_tail(&nmtd->mtd);
1028			s3c2410_nand_add_partition(info, nmtd, sets);
1029		}
1030
1031		if (sets != NULL)
1032			sets++;
1033	}
1034
1035	err = s3c2410_nand_cpufreq_register(info);
1036	if (err < 0) {
1037		dev_err(&pdev->dev, "failed to init cpufreq support\n");
1038		goto exit_error;
1039	}
1040
1041	if (allow_clk_suspend(info)) {
1042		dev_info(&pdev->dev, "clock idle support enabled\n");
1043		s3c2410_nand_clk_set_state(info, CLOCK_SUSPEND);
1044	}
1045
1046	return 0;
1047
1048 exit_error:
1049	s3c24xx_nand_remove(pdev);
1050
1051	if (err == 0)
1052		err = -EINVAL;
1053	return err;
1054}
1055
1056/* PM Support */
1057#ifdef CONFIG_PM
1058
1059static int s3c24xx_nand_suspend(struct platform_device *dev, pm_message_t pm)
1060{
1061	struct s3c2410_nand_info *info = platform_get_drvdata(dev);
1062
1063	if (info) {
1064		info->save_sel = readl(info->sel_reg);
1065
1066		/* For the moment, we must ensure nFCE is high during
1067		 * the time we are suspended. This really should be
1068		 * handled by suspending the MTDs we are using, but
1069		 * that is currently not the case. */
1070
1071		writel(info->save_sel | info->sel_bit, info->sel_reg);
1072
1073		s3c2410_nand_clk_set_state(info, CLOCK_DISABLE);
1074	}
1075
1076	return 0;
1077}
1078
1079static int s3c24xx_nand_resume(struct platform_device *dev)
1080{
1081	struct s3c2410_nand_info *info = platform_get_drvdata(dev);
1082	unsigned long sel;
1083
1084	if (info) {
1085		s3c2410_nand_clk_set_state(info, CLOCK_ENABLE);
1086		s3c2410_nand_inithw(info);
1087
1088		/* Restore the state of the nFCE line. */
1089
1090		sel = readl(info->sel_reg);
1091		sel &= ~info->sel_bit;
1092		sel |= info->save_sel & info->sel_bit;
1093		writel(sel, info->sel_reg);
1094
1095		s3c2410_nand_clk_set_state(info, CLOCK_SUSPEND);
1096	}
1097
1098	return 0;
1099}
1100
1101#else
1102#define s3c24xx_nand_suspend NULL
1103#define s3c24xx_nand_resume NULL
1104#endif
1105
1106/* driver device registration */
1107
1108static struct platform_device_id s3c24xx_driver_ids[] = {
1109	{
1110		.name		= "s3c2410-nand",
1111		.driver_data	= TYPE_S3C2410,
1112	}, {
1113		.name		= "s3c2440-nand",
1114		.driver_data	= TYPE_S3C2440,
1115	}, {
1116		.name		= "s3c2412-nand",
1117		.driver_data	= TYPE_S3C2412,
1118	}, {
1119		.name		= "s3c6400-nand",
1120		.driver_data	= TYPE_S3C2412, /* compatible with 2412 */
1121	},
1122	{ }
1123};
1124
1125MODULE_DEVICE_TABLE(platform, s3c24xx_driver_ids);
1126
1127static struct platform_driver s3c24xx_nand_driver = {
1128	.probe		= s3c24xx_nand_probe,
1129	.remove		= s3c24xx_nand_remove,
1130	.suspend	= s3c24xx_nand_suspend,
1131	.resume		= s3c24xx_nand_resume,
1132	.id_table	= s3c24xx_driver_ids,
1133	.driver		= {
1134		.name	= "s3c24xx-nand",
1135	},
1136};
1137
1138module_platform_driver(s3c24xx_nand_driver);
1139
1140MODULE_LICENSE("GPL");
1141MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
1142MODULE_DESCRIPTION("S3C24XX MTD NAND driver");
1143