s3c2410.c revision 9db41f9edcb87ae050fcb171c44be7f212728d54
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#ifdef CONFIG_MTD_NAND_S3C2410_DEBUG
25#define DEBUG
26#endif
27
28#include <linux/module.h>
29#include <linux/types.h>
30#include <linux/init.h>
31#include <linux/kernel.h>
32#include <linux/string.h>
33#include <linux/ioport.h>
34#include <linux/platform_device.h>
35#include <linux/delay.h>
36#include <linux/err.h>
37#include <linux/slab.h>
38#include <linux/clk.h>
39#include <linux/cpufreq.h>
40
41#include <linux/mtd/mtd.h>
42#include <linux/mtd/nand.h>
43#include <linux/mtd/nand_ecc.h>
44#include <linux/mtd/partitions.h>
45
46#include <asm/io.h>
47
48#include <plat/regs-nand.h>
49#include <plat/nand.h>
50
51#ifdef CONFIG_MTD_NAND_S3C2410_HWECC
52static int hardware_ecc = 1;
53#else
54static int hardware_ecc = 0;
55#endif
56
57#ifdef CONFIG_MTD_NAND_S3C2410_CLKSTOP
58static int clock_stop = 1;
59#else
60static const int clock_stop = 0;
61#endif
62
63
64/* new oob placement block for use with hardware ecc generation
65 */
66
67static struct nand_ecclayout nand_hw_eccoob = {
68	.eccbytes = 3,
69	.eccpos = {0, 1, 2},
70	.oobfree = {{8, 8}}
71};
72
73/* controller and mtd information */
74
75struct s3c2410_nand_info;
76
77/**
78 * struct s3c2410_nand_mtd - driver MTD structure
79 * @mtd: The MTD instance to pass to the MTD layer.
80 * @chip: The NAND chip information.
81 * @set: The platform information supplied for this set of NAND chips.
82 * @info: Link back to the hardware information.
83 * @scan_res: The result from calling nand_scan_ident().
84*/
85struct s3c2410_nand_mtd {
86	struct mtd_info			mtd;
87	struct nand_chip		chip;
88	struct s3c2410_nand_set		*set;
89	struct s3c2410_nand_info	*info;
90	int				scan_res;
91};
92
93enum s3c_cpu_type {
94	TYPE_S3C2410,
95	TYPE_S3C2412,
96	TYPE_S3C2440,
97};
98
99/* overview of the s3c2410 nand state */
100
101/**
102 * struct s3c2410_nand_info - NAND controller state.
103 * @mtds: An array of MTD instances on this controoler.
104 * @platform: The platform data for this board.
105 * @device: The platform device we bound to.
106 * @area: The IO area resource that came from request_mem_region().
107 * @clk: The clock resource for this controller.
108 * @regs: The area mapped for the hardware registers described by @area.
109 * @sel_reg: Pointer to the register controlling the NAND selection.
110 * @sel_bit: The bit in @sel_reg to select the NAND chip.
111 * @mtd_count: The number of MTDs created from this controller.
112 * @save_sel: The contents of @sel_reg to be saved over suspend.
113 * @clk_rate: The clock rate from @clk.
114 * @cpu_type: The exact type of this controller.
115 */
116struct s3c2410_nand_info {
117	/* mtd info */
118	struct nand_hw_control		controller;
119	struct s3c2410_nand_mtd		*mtds;
120	struct s3c2410_platform_nand	*platform;
121
122	/* device info */
123	struct device			*device;
124	struct resource			*area;
125	struct clk			*clk;
126	void __iomem			*regs;
127	void __iomem			*sel_reg;
128	int				sel_bit;
129	int				mtd_count;
130	unsigned long			save_sel;
131	unsigned long			clk_rate;
132
133	enum s3c_cpu_type		cpu_type;
134
135#ifdef CONFIG_CPU_FREQ
136	struct notifier_block	freq_transition;
137#endif
138};
139
140/* conversion functions */
141
142static struct s3c2410_nand_mtd *s3c2410_nand_mtd_toours(struct mtd_info *mtd)
143{
144	return container_of(mtd, struct s3c2410_nand_mtd, mtd);
145}
146
147static struct s3c2410_nand_info *s3c2410_nand_mtd_toinfo(struct mtd_info *mtd)
148{
149	return s3c2410_nand_mtd_toours(mtd)->info;
150}
151
152static struct s3c2410_nand_info *to_nand_info(struct platform_device *dev)
153{
154	return platform_get_drvdata(dev);
155}
156
157static struct s3c2410_platform_nand *to_nand_plat(struct platform_device *dev)
158{
159	return dev->dev.platform_data;
160}
161
162static inline int allow_clk_stop(struct s3c2410_nand_info *info)
163{
164	return clock_stop;
165}
166
167/* timing calculations */
168
169#define NS_IN_KHZ 1000000
170
171/**
172 * s3c_nand_calc_rate - calculate timing data.
173 * @wanted: The cycle time in nanoseconds.
174 * @clk: The clock rate in kHz.
175 * @max: The maximum divider value.
176 *
177 * Calculate the timing value from the given parameters.
178 */
179static int s3c_nand_calc_rate(int wanted, unsigned long clk, int max)
180{
181	int result;
182
183	result = (wanted * clk) / NS_IN_KHZ;
184	result++;
185
186	pr_debug("result %d from %ld, %d\n", result, clk, wanted);
187
188	if (result > max) {
189		printk("%d ns is too big for current clock rate %ld\n", wanted, clk);
190		return -1;
191	}
192
193	if (result < 1)
194		result = 1;
195
196	return result;
197}
198
199#define to_ns(ticks,clk) (((ticks) * NS_IN_KHZ) / (unsigned int)(clk))
200
201/* controller setup */
202
203/**
204 * s3c2410_nand_setrate - setup controller timing information.
205 * @info: The controller instance.
206 *
207 * Given the information supplied by the platform, calculate and set
208 * the necessary timing registers in the hardware to generate the
209 * necessary timing cycles to the hardware.
210 */
211static int s3c2410_nand_setrate(struct s3c2410_nand_info *info)
212{
213	struct s3c2410_platform_nand *plat = info->platform;
214	int tacls_max = (info->cpu_type == TYPE_S3C2412) ? 8 : 4;
215	int tacls, twrph0, twrph1;
216	unsigned long clkrate = clk_get_rate(info->clk);
217	unsigned long uninitialized_var(set), cfg, uninitialized_var(mask);
218	unsigned long flags;
219
220	/* calculate the timing information for the controller */
221
222	info->clk_rate = clkrate;
223	clkrate /= 1000;	/* turn clock into kHz for ease of use */
224
225	if (plat != NULL) {
226		tacls = s3c_nand_calc_rate(plat->tacls, clkrate, tacls_max);
227		twrph0 = s3c_nand_calc_rate(plat->twrph0, clkrate, 8);
228		twrph1 = s3c_nand_calc_rate(plat->twrph1, clkrate, 8);
229	} else {
230		/* default timings */
231		tacls = tacls_max;
232		twrph0 = 8;
233		twrph1 = 8;
234	}
235
236	if (tacls < 0 || twrph0 < 0 || twrph1 < 0) {
237		dev_err(info->device, "cannot get suitable timings\n");
238		return -EINVAL;
239	}
240
241	dev_info(info->device, "Tacls=%d, %dns Twrph0=%d %dns, Twrph1=%d %dns\n",
242	       tacls, to_ns(tacls, clkrate), twrph0, to_ns(twrph0, clkrate), twrph1, to_ns(twrph1, clkrate));
243
244	switch (info->cpu_type) {
245	case TYPE_S3C2410:
246		mask = (S3C2410_NFCONF_TACLS(3) |
247			S3C2410_NFCONF_TWRPH0(7) |
248			S3C2410_NFCONF_TWRPH1(7));
249		set = S3C2410_NFCONF_EN;
250		set |= S3C2410_NFCONF_TACLS(tacls - 1);
251		set |= S3C2410_NFCONF_TWRPH0(twrph0 - 1);
252		set |= S3C2410_NFCONF_TWRPH1(twrph1 - 1);
253		break;
254
255	case TYPE_S3C2440:
256	case TYPE_S3C2412:
257		mask = (S3C2410_NFCONF_TACLS(tacls_max - 1) |
258			S3C2410_NFCONF_TWRPH0(7) |
259			S3C2410_NFCONF_TWRPH1(7));
260
261		set = S3C2440_NFCONF_TACLS(tacls - 1);
262		set |= S3C2440_NFCONF_TWRPH0(twrph0 - 1);
263		set |= S3C2440_NFCONF_TWRPH1(twrph1 - 1);
264		break;
265
266	default:
267		BUG();
268	}
269
270	local_irq_save(flags);
271
272	cfg = readl(info->regs + S3C2410_NFCONF);
273	cfg &= ~mask;
274	cfg |= set;
275	writel(cfg, info->regs + S3C2410_NFCONF);
276
277	local_irq_restore(flags);
278
279	dev_dbg(info->device, "NF_CONF is 0x%lx\n", cfg);
280
281	return 0;
282}
283
284/**
285 * s3c2410_nand_inithw - basic hardware initialisation
286 * @info: The hardware state.
287 *
288 * Do the basic initialisation of the hardware, using s3c2410_nand_setrate()
289 * to setup the hardware access speeds and set the controller to be enabled.
290*/
291static int s3c2410_nand_inithw(struct s3c2410_nand_info *info)
292{
293	int ret;
294
295	ret = s3c2410_nand_setrate(info);
296	if (ret < 0)
297		return ret;
298
299 	switch (info->cpu_type) {
300 	case TYPE_S3C2410:
301	default:
302		break;
303
304 	case TYPE_S3C2440:
305 	case TYPE_S3C2412:
306		/* enable the controller and de-assert nFCE */
307
308		writel(S3C2440_NFCONT_ENABLE, info->regs + S3C2440_NFCONT);
309	}
310
311	return 0;
312}
313
314/**
315 * s3c2410_nand_select_chip - select the given nand chip
316 * @mtd: The MTD instance for this chip.
317 * @chip: The chip number.
318 *
319 * This is called by the MTD layer to either select a given chip for the
320 * @mtd instance, or to indicate that the access has finished and the
321 * chip can be de-selected.
322 *
323 * The routine ensures that the nFCE line is correctly setup, and any
324 * platform specific selection code is called to route nFCE to the specific
325 * chip.
326 */
327static void s3c2410_nand_select_chip(struct mtd_info *mtd, int chip)
328{
329	struct s3c2410_nand_info *info;
330	struct s3c2410_nand_mtd *nmtd;
331	struct nand_chip *this = mtd->priv;
332	unsigned long cur;
333
334	nmtd = this->priv;
335	info = nmtd->info;
336
337	if (chip != -1 && allow_clk_stop(info))
338		clk_enable(info->clk);
339
340	cur = readl(info->sel_reg);
341
342	if (chip == -1) {
343		cur |= info->sel_bit;
344	} else {
345		if (nmtd->set != NULL && chip > nmtd->set->nr_chips) {
346			dev_err(info->device, "invalid chip %d\n", chip);
347			return;
348		}
349
350		if (info->platform != NULL) {
351			if (info->platform->select_chip != NULL)
352				(info->platform->select_chip) (nmtd->set, chip);
353		}
354
355		cur &= ~info->sel_bit;
356	}
357
358	writel(cur, info->sel_reg);
359
360	if (chip == -1 && allow_clk_stop(info))
361		clk_disable(info->clk);
362}
363
364/* s3c2410_nand_hwcontrol
365 *
366 * Issue command and address cycles to the chip
367*/
368
369static void s3c2410_nand_hwcontrol(struct mtd_info *mtd, int cmd,
370				   unsigned int ctrl)
371{
372	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
373
374	if (cmd == NAND_CMD_NONE)
375		return;
376
377	if (ctrl & NAND_CLE)
378		writeb(cmd, info->regs + S3C2410_NFCMD);
379	else
380		writeb(cmd, info->regs + S3C2410_NFADDR);
381}
382
383/* command and control functions */
384
385static void s3c2440_nand_hwcontrol(struct mtd_info *mtd, int cmd,
386				   unsigned int ctrl)
387{
388	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
389
390	if (cmd == NAND_CMD_NONE)
391		return;
392
393	if (ctrl & NAND_CLE)
394		writeb(cmd, info->regs + S3C2440_NFCMD);
395	else
396		writeb(cmd, info->regs + S3C2440_NFADDR);
397}
398
399/* s3c2410_nand_devready()
400 *
401 * returns 0 if the nand is busy, 1 if it is ready
402*/
403
404static int s3c2410_nand_devready(struct mtd_info *mtd)
405{
406	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
407	return readb(info->regs + S3C2410_NFSTAT) & S3C2410_NFSTAT_BUSY;
408}
409
410static int s3c2440_nand_devready(struct mtd_info *mtd)
411{
412	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
413	return readb(info->regs + S3C2440_NFSTAT) & S3C2440_NFSTAT_READY;
414}
415
416static int s3c2412_nand_devready(struct mtd_info *mtd)
417{
418	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
419	return readb(info->regs + S3C2412_NFSTAT) & S3C2412_NFSTAT_READY;
420}
421
422/* ECC handling functions */
423
424static int s3c2410_nand_correct_data(struct mtd_info *mtd, u_char *dat,
425				     u_char *read_ecc, u_char *calc_ecc)
426{
427	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
428	unsigned int diff0, diff1, diff2;
429	unsigned int bit, byte;
430
431	pr_debug("%s(%p,%p,%p,%p)\n", __func__, mtd, dat, read_ecc, calc_ecc);
432
433	diff0 = read_ecc[0] ^ calc_ecc[0];
434	diff1 = read_ecc[1] ^ calc_ecc[1];
435	diff2 = read_ecc[2] ^ calc_ecc[2];
436
437	pr_debug("%s: rd %02x%02x%02x calc %02x%02x%02x diff %02x%02x%02x\n",
438		 __func__,
439		 read_ecc[0], read_ecc[1], read_ecc[2],
440		 calc_ecc[0], calc_ecc[1], calc_ecc[2],
441		 diff0, diff1, diff2);
442
443	if (diff0 == 0 && diff1 == 0 && diff2 == 0)
444		return 0;		/* ECC is ok */
445
446	/* sometimes people do not think about using the ECC, so check
447	 * to see if we have an 0xff,0xff,0xff read ECC and then ignore
448	 * the error, on the assumption that this is an un-eccd page.
449	 */
450	if (read_ecc[0] == 0xff && read_ecc[1] == 0xff && read_ecc[2] == 0xff
451	    && info->platform->ignore_unset_ecc)
452		return 0;
453
454	/* Can we correct this ECC (ie, one row and column change).
455	 * Note, this is similar to the 256 error code on smartmedia */
456
457	if (((diff0 ^ (diff0 >> 1)) & 0x55) == 0x55 &&
458	    ((diff1 ^ (diff1 >> 1)) & 0x55) == 0x55 &&
459	    ((diff2 ^ (diff2 >> 1)) & 0x55) == 0x55) {
460		/* calculate the bit position of the error */
461
462		bit  = ((diff2 >> 3) & 1) |
463		       ((diff2 >> 4) & 2) |
464		       ((diff2 >> 5) & 4);
465
466		/* calculate the byte position of the error */
467
468		byte = ((diff2 << 7) & 0x100) |
469		       ((diff1 << 0) & 0x80)  |
470		       ((diff1 << 1) & 0x40)  |
471		       ((diff1 << 2) & 0x20)  |
472		       ((diff1 << 3) & 0x10)  |
473		       ((diff0 >> 4) & 0x08)  |
474		       ((diff0 >> 3) & 0x04)  |
475		       ((diff0 >> 2) & 0x02)  |
476		       ((diff0 >> 1) & 0x01);
477
478		dev_dbg(info->device, "correcting error bit %d, byte %d\n",
479			bit, byte);
480
481		dat[byte] ^= (1 << bit);
482		return 1;
483	}
484
485	/* if there is only one bit difference in the ECC, then
486	 * one of only a row or column parity has changed, which
487	 * means the error is most probably in the ECC itself */
488
489	diff0 |= (diff1 << 8);
490	diff0 |= (diff2 << 16);
491
492	if ((diff0 & ~(1<<fls(diff0))) == 0)
493		return 1;
494
495	return -1;
496}
497
498/* ECC functions
499 *
500 * These allow the s3c2410 and s3c2440 to use the controller's ECC
501 * generator block to ECC the data as it passes through]
502*/
503
504static void s3c2410_nand_enable_hwecc(struct mtd_info *mtd, int mode)
505{
506	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
507	unsigned long ctrl;
508
509	ctrl = readl(info->regs + S3C2410_NFCONF);
510	ctrl |= S3C2410_NFCONF_INITECC;
511	writel(ctrl, info->regs + S3C2410_NFCONF);
512}
513
514static void s3c2412_nand_enable_hwecc(struct mtd_info *mtd, int mode)
515{
516	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
517	unsigned long ctrl;
518
519	ctrl = readl(info->regs + S3C2440_NFCONT);
520	writel(ctrl | S3C2412_NFCONT_INIT_MAIN_ECC, info->regs + S3C2440_NFCONT);
521}
522
523static void s3c2440_nand_enable_hwecc(struct mtd_info *mtd, int mode)
524{
525	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
526	unsigned long ctrl;
527
528	ctrl = readl(info->regs + S3C2440_NFCONT);
529	writel(ctrl | S3C2440_NFCONT_INITECC, info->regs + S3C2440_NFCONT);
530}
531
532static int s3c2410_nand_calculate_ecc(struct mtd_info *mtd, const u_char *dat, u_char *ecc_code)
533{
534	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
535
536	ecc_code[0] = readb(info->regs + S3C2410_NFECC + 0);
537	ecc_code[1] = readb(info->regs + S3C2410_NFECC + 1);
538	ecc_code[2] = readb(info->regs + S3C2410_NFECC + 2);
539
540	pr_debug("%s: returning ecc %02x%02x%02x\n", __func__,
541		 ecc_code[0], ecc_code[1], ecc_code[2]);
542
543	return 0;
544}
545
546static int s3c2412_nand_calculate_ecc(struct mtd_info *mtd, const u_char *dat, u_char *ecc_code)
547{
548	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
549	unsigned long ecc = readl(info->regs + S3C2412_NFMECC0);
550
551	ecc_code[0] = ecc;
552	ecc_code[1] = ecc >> 8;
553	ecc_code[2] = ecc >> 16;
554
555	pr_debug("calculate_ecc: returning ecc %02x,%02x,%02x\n", ecc_code[0], ecc_code[1], ecc_code[2]);
556
557	return 0;
558}
559
560static int s3c2440_nand_calculate_ecc(struct mtd_info *mtd, const u_char *dat, u_char *ecc_code)
561{
562	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
563	unsigned long ecc = readl(info->regs + S3C2440_NFMECC0);
564
565	ecc_code[0] = ecc;
566	ecc_code[1] = ecc >> 8;
567	ecc_code[2] = ecc >> 16;
568
569	pr_debug("%s: returning ecc %06lx\n", __func__, ecc & 0xffffff);
570
571	return 0;
572}
573
574/* over-ride the standard functions for a little more speed. We can
575 * use read/write block to move the data buffers to/from the controller
576*/
577
578static void s3c2410_nand_read_buf(struct mtd_info *mtd, u_char *buf, int len)
579{
580	struct nand_chip *this = mtd->priv;
581	readsb(this->IO_ADDR_R, buf, len);
582}
583
584static void s3c2440_nand_read_buf(struct mtd_info *mtd, u_char *buf, int len)
585{
586	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
587	readsl(info->regs + S3C2440_NFDATA, buf, len / 4);
588}
589
590static void s3c2410_nand_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
591{
592	struct nand_chip *this = mtd->priv;
593	writesb(this->IO_ADDR_W, buf, len);
594}
595
596static void s3c2440_nand_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
597{
598	struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
599	writesl(info->regs + S3C2440_NFDATA, buf, len / 4);
600}
601
602/* cpufreq driver support */
603
604#ifdef CONFIG_CPU_FREQ
605
606static int s3c2410_nand_cpufreq_transition(struct notifier_block *nb,
607					  unsigned long val, void *data)
608{
609	struct s3c2410_nand_info *info;
610	unsigned long newclk;
611
612	info = container_of(nb, struct s3c2410_nand_info, freq_transition);
613	newclk = clk_get_rate(info->clk);
614
615	if ((val == CPUFREQ_POSTCHANGE && newclk < info->clk_rate) ||
616	    (val == CPUFREQ_PRECHANGE && newclk > info->clk_rate)) {
617		s3c2410_nand_setrate(info);
618	}
619
620	return 0;
621}
622
623static inline int s3c2410_nand_cpufreq_register(struct s3c2410_nand_info *info)
624{
625	info->freq_transition.notifier_call = s3c2410_nand_cpufreq_transition;
626
627	return cpufreq_register_notifier(&info->freq_transition,
628					 CPUFREQ_TRANSITION_NOTIFIER);
629}
630
631static inline void s3c2410_nand_cpufreq_deregister(struct s3c2410_nand_info *info)
632{
633	cpufreq_unregister_notifier(&info->freq_transition,
634				    CPUFREQ_TRANSITION_NOTIFIER);
635}
636
637#else
638static inline int s3c2410_nand_cpufreq_register(struct s3c2410_nand_info *info)
639{
640	return 0;
641}
642
643static inline void s3c2410_nand_cpufreq_deregister(struct s3c2410_nand_info *info)
644{
645}
646#endif
647
648/* device management functions */
649
650static int s3c24xx_nand_remove(struct platform_device *pdev)
651{
652	struct s3c2410_nand_info *info = to_nand_info(pdev);
653
654	platform_set_drvdata(pdev, NULL);
655
656	if (info == NULL)
657		return 0;
658
659	s3c2410_nand_cpufreq_deregister(info);
660
661	/* Release all our mtds  and their partitions, then go through
662	 * freeing the resources used
663	 */
664
665	if (info->mtds != NULL) {
666		struct s3c2410_nand_mtd *ptr = info->mtds;
667		int mtdno;
668
669		for (mtdno = 0; mtdno < info->mtd_count; mtdno++, ptr++) {
670			pr_debug("releasing mtd %d (%p)\n", mtdno, ptr);
671			nand_release(&ptr->mtd);
672		}
673
674		kfree(info->mtds);
675	}
676
677	/* free the common resources */
678
679	if (info->clk != NULL && !IS_ERR(info->clk)) {
680		if (!allow_clk_stop(info))
681			clk_disable(info->clk);
682		clk_put(info->clk);
683	}
684
685	if (info->regs != NULL) {
686		iounmap(info->regs);
687		info->regs = NULL;
688	}
689
690	if (info->area != NULL) {
691		release_resource(info->area);
692		kfree(info->area);
693		info->area = NULL;
694	}
695
696	kfree(info);
697
698	return 0;
699}
700
701#ifdef CONFIG_MTD_PARTITIONS
702const char *part_probes[] = { "cmdlinepart", NULL };
703static int s3c2410_nand_add_partition(struct s3c2410_nand_info *info,
704				      struct s3c2410_nand_mtd *mtd,
705				      struct s3c2410_nand_set *set)
706{
707	struct mtd_partition *part_info;
708	int nr_part = 0;
709
710	if (set == NULL)
711		return add_mtd_device(&mtd->mtd);
712
713	if (set->nr_partitions == 0) {
714		mtd->mtd.name = set->name;
715		nr_part = parse_mtd_partitions(&mtd->mtd, part_probes,
716						&part_info, 0);
717	} else {
718		if (set->nr_partitions > 0 && set->partitions != NULL) {
719			nr_part = set->nr_partitions;
720			part_info = set->partitions;
721		}
722	}
723
724	if (nr_part > 0 && part_info)
725		return add_mtd_partitions(&mtd->mtd, part_info, nr_part);
726
727	return add_mtd_device(&mtd->mtd);
728}
729#else
730static int s3c2410_nand_add_partition(struct s3c2410_nand_info *info,
731				      struct s3c2410_nand_mtd *mtd,
732				      struct s3c2410_nand_set *set)
733{
734	return add_mtd_device(&mtd->mtd);
735}
736#endif
737
738/**
739 * s3c2410_nand_init_chip - initialise a single instance of an chip
740 * @info: The base NAND controller the chip is on.
741 * @nmtd: The new controller MTD instance to fill in.
742 * @set: The information passed from the board specific platform data.
743 *
744 * Initialise the given @nmtd from the information in @info and @set. This
745 * readies the structure for use with the MTD layer functions by ensuring
746 * all pointers are setup and the necessary control routines selected.
747 */
748static void s3c2410_nand_init_chip(struct s3c2410_nand_info *info,
749				   struct s3c2410_nand_mtd *nmtd,
750				   struct s3c2410_nand_set *set)
751{
752	struct nand_chip *chip = &nmtd->chip;
753	void __iomem *regs = info->regs;
754
755	chip->write_buf    = s3c2410_nand_write_buf;
756	chip->read_buf     = s3c2410_nand_read_buf;
757	chip->select_chip  = s3c2410_nand_select_chip;
758	chip->chip_delay   = 50;
759	chip->priv	   = nmtd;
760	chip->options	   = 0;
761	chip->controller   = &info->controller;
762
763	switch (info->cpu_type) {
764	case TYPE_S3C2410:
765		chip->IO_ADDR_W = regs + S3C2410_NFDATA;
766		info->sel_reg   = regs + S3C2410_NFCONF;
767		info->sel_bit	= S3C2410_NFCONF_nFCE;
768		chip->cmd_ctrl  = s3c2410_nand_hwcontrol;
769		chip->dev_ready = s3c2410_nand_devready;
770		break;
771
772	case TYPE_S3C2440:
773		chip->IO_ADDR_W = regs + S3C2440_NFDATA;
774		info->sel_reg   = regs + S3C2440_NFCONT;
775		info->sel_bit	= S3C2440_NFCONT_nFCE;
776		chip->cmd_ctrl  = s3c2440_nand_hwcontrol;
777		chip->dev_ready = s3c2440_nand_devready;
778		chip->read_buf  = s3c2440_nand_read_buf;
779		chip->write_buf	= s3c2440_nand_write_buf;
780		break;
781
782	case TYPE_S3C2412:
783		chip->IO_ADDR_W = regs + S3C2440_NFDATA;
784		info->sel_reg   = regs + S3C2440_NFCONT;
785		info->sel_bit	= S3C2412_NFCONT_nFCE0;
786		chip->cmd_ctrl  = s3c2440_nand_hwcontrol;
787		chip->dev_ready = s3c2412_nand_devready;
788
789		if (readl(regs + S3C2410_NFCONF) & S3C2412_NFCONF_NANDBOOT)
790			dev_info(info->device, "System booted from NAND\n");
791
792		break;
793  	}
794
795	chip->IO_ADDR_R = chip->IO_ADDR_W;
796
797	nmtd->info	   = info;
798	nmtd->mtd.priv	   = chip;
799	nmtd->mtd.owner    = THIS_MODULE;
800	nmtd->set	   = set;
801
802	if (hardware_ecc) {
803		chip->ecc.calculate = s3c2410_nand_calculate_ecc;
804		chip->ecc.correct   = s3c2410_nand_correct_data;
805		chip->ecc.mode	    = NAND_ECC_HW;
806
807		switch (info->cpu_type) {
808		case TYPE_S3C2410:
809			chip->ecc.hwctl	    = s3c2410_nand_enable_hwecc;
810			chip->ecc.calculate = s3c2410_nand_calculate_ecc;
811			break;
812
813		case TYPE_S3C2412:
814  			chip->ecc.hwctl     = s3c2412_nand_enable_hwecc;
815  			chip->ecc.calculate = s3c2412_nand_calculate_ecc;
816			break;
817
818		case TYPE_S3C2440:
819  			chip->ecc.hwctl     = s3c2440_nand_enable_hwecc;
820  			chip->ecc.calculate = s3c2440_nand_calculate_ecc;
821			break;
822
823		}
824	} else {
825		chip->ecc.mode	    = NAND_ECC_SOFT;
826	}
827
828	if (set->ecc_layout != NULL)
829		chip->ecc.layout = set->ecc_layout;
830
831	if (set->disable_ecc)
832		chip->ecc.mode	= NAND_ECC_NONE;
833
834	switch (chip->ecc.mode) {
835	case NAND_ECC_NONE:
836		dev_info(info->device, "NAND ECC disabled\n");
837		break;
838	case NAND_ECC_SOFT:
839		dev_info(info->device, "NAND soft ECC\n");
840		break;
841	case NAND_ECC_HW:
842		dev_info(info->device, "NAND hardware ECC\n");
843		break;
844	default:
845		dev_info(info->device, "NAND ECC UNKNOWN\n");
846		break;
847	}
848
849	/* If you use u-boot BBT creation code, specifying this flag will
850	 * let the kernel fish out the BBT from the NAND, and also skip the
851	 * full NAND scan that can take 1/2s or so. Little things... */
852	if (set->flash_bbt)
853		chip->options |= NAND_USE_FLASH_BBT | NAND_SKIP_BBTSCAN;
854}
855
856/**
857 * s3c2410_nand_update_chip - post probe update
858 * @info: The controller instance.
859 * @nmtd: The driver version of the MTD instance.
860 *
861 * This routine is called after the chip probe has succesfully completed
862 * and the relevant per-chip information updated. This call ensure that
863 * we update the internal state accordingly.
864 *
865 * The internal state is currently limited to the ECC state information.
866*/
867static void s3c2410_nand_update_chip(struct s3c2410_nand_info *info,
868				     struct s3c2410_nand_mtd *nmtd)
869{
870	struct nand_chip *chip = &nmtd->chip;
871
872	dev_dbg(info->device, "chip %p => page shift %d\n",
873		chip, chip->page_shift);
874
875	if (chip->ecc.mode != NAND_ECC_HW)
876		return;
877
878		/* change the behaviour depending on wether we are using
879		 * the large or small page nand device */
880
881	if (chip->page_shift > 10) {
882		chip->ecc.size	    = 256;
883		chip->ecc.bytes	    = 3;
884	} else {
885		chip->ecc.size	    = 512;
886		chip->ecc.bytes	    = 3;
887		chip->ecc.layout    = &nand_hw_eccoob;
888	}
889}
890
891/* s3c24xx_nand_probe
892 *
893 * called by device layer when it finds a device matching
894 * one our driver can handled. This code checks to see if
895 * it can allocate all necessary resources then calls the
896 * nand layer to look for devices
897*/
898static int s3c24xx_nand_probe(struct platform_device *pdev)
899{
900	struct s3c2410_platform_nand *plat = to_nand_plat(pdev);
901	enum s3c_cpu_type cpu_type;
902	struct s3c2410_nand_info *info;
903	struct s3c2410_nand_mtd *nmtd;
904	struct s3c2410_nand_set *sets;
905	struct resource *res;
906	int err = 0;
907	int size;
908	int nr_sets;
909	int setno;
910
911	cpu_type = platform_get_device_id(pdev)->driver_data;
912
913	pr_debug("s3c2410_nand_probe(%p)\n", pdev);
914
915	info = kmalloc(sizeof(*info), GFP_KERNEL);
916	if (info == NULL) {
917		dev_err(&pdev->dev, "no memory for flash info\n");
918		err = -ENOMEM;
919		goto exit_error;
920	}
921
922	memset(info, 0, sizeof(*info));
923	platform_set_drvdata(pdev, info);
924
925	spin_lock_init(&info->controller.lock);
926	init_waitqueue_head(&info->controller.wq);
927
928	/* get the clock source and enable it */
929
930	info->clk = clk_get(&pdev->dev, "nand");
931	if (IS_ERR(info->clk)) {
932		dev_err(&pdev->dev, "failed to get clock\n");
933		err = -ENOENT;
934		goto exit_error;
935	}
936
937	clk_enable(info->clk);
938
939	/* allocate and map the resource */
940
941	/* currently we assume we have the one resource */
942	res  = pdev->resource;
943	size = res->end - res->start + 1;
944
945	info->area = request_mem_region(res->start, size, pdev->name);
946
947	if (info->area == NULL) {
948		dev_err(&pdev->dev, "cannot reserve register region\n");
949		err = -ENOENT;
950		goto exit_error;
951	}
952
953	info->device     = &pdev->dev;
954	info->platform   = plat;
955	info->regs       = ioremap(res->start, size);
956	info->cpu_type   = cpu_type;
957
958	if (info->regs == NULL) {
959		dev_err(&pdev->dev, "cannot reserve register region\n");
960		err = -EIO;
961		goto exit_error;
962	}
963
964	dev_dbg(&pdev->dev, "mapped registers at %p\n", info->regs);
965
966	/* initialise the hardware */
967
968	err = s3c2410_nand_inithw(info);
969	if (err != 0)
970		goto exit_error;
971
972	sets = (plat != NULL) ? plat->sets : NULL;
973	nr_sets = (plat != NULL) ? plat->nr_sets : 1;
974
975	info->mtd_count = nr_sets;
976
977	/* allocate our information */
978
979	size = nr_sets * sizeof(*info->mtds);
980	info->mtds = kmalloc(size, GFP_KERNEL);
981	if (info->mtds == NULL) {
982		dev_err(&pdev->dev, "failed to allocate mtd storage\n");
983		err = -ENOMEM;
984		goto exit_error;
985	}
986
987	memset(info->mtds, 0, size);
988
989	/* initialise all possible chips */
990
991	nmtd = info->mtds;
992
993	for (setno = 0; setno < nr_sets; setno++, nmtd++) {
994		pr_debug("initialising set %d (%p, info %p)\n", setno, nmtd, info);
995
996		s3c2410_nand_init_chip(info, nmtd, sets);
997
998		nmtd->scan_res = nand_scan_ident(&nmtd->mtd,
999						 (sets) ? sets->nr_chips : 1);
1000
1001		if (nmtd->scan_res == 0) {
1002			s3c2410_nand_update_chip(info, nmtd);
1003			nand_scan_tail(&nmtd->mtd);
1004			s3c2410_nand_add_partition(info, nmtd, sets);
1005		}
1006
1007		if (sets != NULL)
1008			sets++;
1009	}
1010
1011	err = s3c2410_nand_cpufreq_register(info);
1012	if (err < 0) {
1013		dev_err(&pdev->dev, "failed to init cpufreq support\n");
1014		goto exit_error;
1015	}
1016
1017	if (allow_clk_stop(info)) {
1018		dev_info(&pdev->dev, "clock idle support enabled\n");
1019		clk_disable(info->clk);
1020	}
1021
1022	pr_debug("initialised ok\n");
1023	return 0;
1024
1025 exit_error:
1026	s3c24xx_nand_remove(pdev);
1027
1028	if (err == 0)
1029		err = -EINVAL;
1030	return err;
1031}
1032
1033/* PM Support */
1034#ifdef CONFIG_PM
1035
1036static int s3c24xx_nand_suspend(struct platform_device *dev, pm_message_t pm)
1037{
1038	struct s3c2410_nand_info *info = platform_get_drvdata(dev);
1039
1040	if (info) {
1041		info->save_sel = readl(info->sel_reg);
1042
1043		/* For the moment, we must ensure nFCE is high during
1044		 * the time we are suspended. This really should be
1045		 * handled by suspending the MTDs we are using, but
1046		 * that is currently not the case. */
1047
1048		writel(info->save_sel | info->sel_bit, info->sel_reg);
1049
1050		if (!allow_clk_stop(info))
1051			clk_disable(info->clk);
1052	}
1053
1054	return 0;
1055}
1056
1057static int s3c24xx_nand_resume(struct platform_device *dev)
1058{
1059	struct s3c2410_nand_info *info = platform_get_drvdata(dev);
1060	unsigned long sel;
1061
1062	if (info) {
1063		clk_enable(info->clk);
1064		s3c2410_nand_inithw(info);
1065
1066		/* Restore the state of the nFCE line. */
1067
1068		sel = readl(info->sel_reg);
1069		sel &= ~info->sel_bit;
1070		sel |= info->save_sel & info->sel_bit;
1071		writel(sel, info->sel_reg);
1072
1073		if (allow_clk_stop(info))
1074			clk_disable(info->clk);
1075	}
1076
1077	return 0;
1078}
1079
1080#else
1081#define s3c24xx_nand_suspend NULL
1082#define s3c24xx_nand_resume NULL
1083#endif
1084
1085/* driver device registration */
1086
1087static struct platform_device_id s3c24xx_driver_ids[] = {
1088	{
1089		.name		= "s3c2410-nand",
1090		.driver_data	= TYPE_S3C2410,
1091	}, {
1092		.name		= "s3c2440-nand",
1093		.driver_data	= TYPE_S3C2440,
1094	}, {
1095		.name		= "s3c2412-nand",
1096		.driver_data	= TYPE_S3C2412,
1097	},
1098	{ }
1099};
1100
1101MODULE_DEVICE_TABLE(platform, s3c24xx_driver_ids);
1102
1103static struct platform_driver s3c24xx_nand_driver = {
1104	.probe		= s3c24xx_nand_probe,
1105	.remove		= s3c24xx_nand_remove,
1106	.suspend	= s3c24xx_nand_suspend,
1107	.resume		= s3c24xx_nand_resume,
1108	.id_table	= s3c24xx_driver_ids,
1109	.driver		= {
1110		.name	= "s3c24xx-nand",
1111		.owner	= THIS_MODULE,
1112	},
1113};
1114
1115static int __init s3c2410_nand_init(void)
1116{
1117	printk("S3C24XX NAND Driver, (c) 2004 Simtec Electronics\n");
1118
1119	return platform_driver_register(&s3c24xx_nand_driver);
1120}
1121
1122static void __exit s3c2410_nand_exit(void)
1123{
1124	platform_driver_unregister(&s3c24xx_nand_driver);
1125}
1126
1127module_init(s3c2410_nand_init);
1128module_exit(s3c2410_nand_exit);
1129
1130MODULE_LICENSE("GPL");
1131MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
1132MODULE_DESCRIPTION("S3C24XX MTD NAND driver");
1133