1 /*
2  * TXx9 NAND flash memory controller driver
3  * Based on RBTX49xx patch from CELF patch archive.
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 as
7  * published by the Free Software Foundation.
8  *
9  * (C) Copyright TOSHIBA CORPORATION 2004-2007
10  * All Rights Reserved.
11  */
12 #include <linux/init.h>
13 #include <linux/slab.h>
14 #include <linux/module.h>
15 #include <linux/platform_device.h>
16 #include <linux/delay.h>
17 #include <linux/mtd/mtd.h>
18 #include <linux/mtd/nand.h>
19 #include <linux/mtd/nand_ecc.h>
20 #include <linux/mtd/partitions.h>
21 #include <linux/io.h>
22 #include <asm/txx9/ndfmc.h>
23 
24 /* TXX9 NDFMC Registers */
25 #define TXX9_NDFDTR	0x00
26 #define TXX9_NDFMCR	0x04
27 #define TXX9_NDFSR	0x08
28 #define TXX9_NDFISR	0x0c
29 #define TXX9_NDFIMR	0x10
30 #define TXX9_NDFSPR	0x14
31 #define TXX9_NDFRSTR	0x18	/* not TX4939 */
32 
33 /* NDFMCR : NDFMC Mode Control */
34 #define TXX9_NDFMCR_WE	0x80
35 #define TXX9_NDFMCR_ECC_ALL	0x60
36 #define TXX9_NDFMCR_ECC_RESET	0x60
37 #define TXX9_NDFMCR_ECC_READ	0x40
38 #define TXX9_NDFMCR_ECC_ON	0x20
39 #define TXX9_NDFMCR_ECC_OFF	0x00
40 #define TXX9_NDFMCR_CE	0x10
41 #define TXX9_NDFMCR_BSPRT	0x04	/* TX4925/TX4926 only */
42 #define TXX9_NDFMCR_ALE	0x02
43 #define TXX9_NDFMCR_CLE	0x01
44 /* TX4939 only */
45 #define TXX9_NDFMCR_X16	0x0400
46 #define TXX9_NDFMCR_DMAREQ_MASK	0x0300
47 #define TXX9_NDFMCR_DMAREQ_NODMA	0x0000
48 #define TXX9_NDFMCR_DMAREQ_128	0x0100
49 #define TXX9_NDFMCR_DMAREQ_256	0x0200
50 #define TXX9_NDFMCR_DMAREQ_512	0x0300
51 #define TXX9_NDFMCR_CS_MASK	0x0c
52 #define TXX9_NDFMCR_CS(ch)	((ch) << 2)
53 
54 /* NDFMCR : NDFMC Status */
55 #define TXX9_NDFSR_BUSY	0x80
56 /* TX4939 only */
57 #define TXX9_NDFSR_DMARUN	0x40
58 
59 /* NDFMCR : NDFMC Reset */
60 #define TXX9_NDFRSTR_RST	0x01
61 
62 struct txx9ndfmc_priv {
63 	struct platform_device *dev;
64 	struct nand_chip chip;
65 	struct mtd_info mtd;
66 	int cs;
67 	const char *mtdname;
68 };
69 
70 #define MAX_TXX9NDFMC_DEV	4
71 struct txx9ndfmc_drvdata {
72 	struct mtd_info *mtds[MAX_TXX9NDFMC_DEV];
73 	void __iomem *base;
74 	unsigned char hold;	/* in gbusclock */
75 	unsigned char spw;	/* in gbusclock */
76 	struct nand_hw_control hw_control;
77 #ifdef CONFIG_MTD_PARTITIONS
78 	struct mtd_partition *parts[MAX_TXX9NDFMC_DEV];
79 #endif
80 };
81 
mtd_to_platdev(struct mtd_info * mtd)82 static struct platform_device *mtd_to_platdev(struct mtd_info *mtd)
83 {
84 	struct nand_chip *chip = mtd->priv;
85 	struct txx9ndfmc_priv *txx9_priv = chip->priv;
86 	return txx9_priv->dev;
87 }
88 
ndregaddr(struct platform_device * dev,unsigned int reg)89 static void __iomem *ndregaddr(struct platform_device *dev, unsigned int reg)
90 {
91 	struct txx9ndfmc_drvdata *drvdata = platform_get_drvdata(dev);
92 	struct txx9ndfmc_platform_data *plat = dev->dev.platform_data;
93 
94 	return drvdata->base + (reg << plat->shift);
95 }
96 
txx9ndfmc_read(struct platform_device * dev,unsigned int reg)97 static u32 txx9ndfmc_read(struct platform_device *dev, unsigned int reg)
98 {
99 	return __raw_readl(ndregaddr(dev, reg));
100 }
101 
txx9ndfmc_write(struct platform_device * dev,u32 val,unsigned int reg)102 static void txx9ndfmc_write(struct platform_device *dev,
103 			    u32 val, unsigned int reg)
104 {
105 	__raw_writel(val, ndregaddr(dev, reg));
106 }
107 
txx9ndfmc_read_byte(struct mtd_info * mtd)108 static uint8_t txx9ndfmc_read_byte(struct mtd_info *mtd)
109 {
110 	struct platform_device *dev = mtd_to_platdev(mtd);
111 
112 	return txx9ndfmc_read(dev, TXX9_NDFDTR);
113 }
114 
txx9ndfmc_write_buf(struct mtd_info * mtd,const uint8_t * buf,int len)115 static void txx9ndfmc_write_buf(struct mtd_info *mtd, const uint8_t *buf,
116 				int len)
117 {
118 	struct platform_device *dev = mtd_to_platdev(mtd);
119 	void __iomem *ndfdtr = ndregaddr(dev, TXX9_NDFDTR);
120 	u32 mcr = txx9ndfmc_read(dev, TXX9_NDFMCR);
121 
122 	txx9ndfmc_write(dev, mcr | TXX9_NDFMCR_WE, TXX9_NDFMCR);
123 	while (len--)
124 		__raw_writel(*buf++, ndfdtr);
125 	txx9ndfmc_write(dev, mcr, TXX9_NDFMCR);
126 }
127 
txx9ndfmc_read_buf(struct mtd_info * mtd,uint8_t * buf,int len)128 static void txx9ndfmc_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
129 {
130 	struct platform_device *dev = mtd_to_platdev(mtd);
131 	void __iomem *ndfdtr = ndregaddr(dev, TXX9_NDFDTR);
132 
133 	while (len--)
134 		*buf++ = __raw_readl(ndfdtr);
135 }
136 
txx9ndfmc_verify_buf(struct mtd_info * mtd,const uint8_t * buf,int len)137 static int txx9ndfmc_verify_buf(struct mtd_info *mtd, const uint8_t *buf,
138 				int len)
139 {
140 	struct platform_device *dev = mtd_to_platdev(mtd);
141 	void __iomem *ndfdtr = ndregaddr(dev, TXX9_NDFDTR);
142 
143 	while (len--)
144 		if (*buf++ != (uint8_t)__raw_readl(ndfdtr))
145 			return -EFAULT;
146 	return 0;
147 }
148 
txx9ndfmc_cmd_ctrl(struct mtd_info * mtd,int cmd,unsigned int ctrl)149 static void txx9ndfmc_cmd_ctrl(struct mtd_info *mtd, int cmd,
150 			       unsigned int ctrl)
151 {
152 	struct nand_chip *chip = mtd->priv;
153 	struct txx9ndfmc_priv *txx9_priv = chip->priv;
154 	struct platform_device *dev = txx9_priv->dev;
155 	struct txx9ndfmc_platform_data *plat = dev->dev.platform_data;
156 
157 	if (ctrl & NAND_CTRL_CHANGE) {
158 		u32 mcr = txx9ndfmc_read(dev, TXX9_NDFMCR);
159 
160 		mcr &= ~(TXX9_NDFMCR_CLE | TXX9_NDFMCR_ALE | TXX9_NDFMCR_CE);
161 		mcr |= ctrl & NAND_CLE ? TXX9_NDFMCR_CLE : 0;
162 		mcr |= ctrl & NAND_ALE ? TXX9_NDFMCR_ALE : 0;
163 		/* TXX9_NDFMCR_CE bit is 0:high 1:low */
164 		mcr |= ctrl & NAND_NCE ? TXX9_NDFMCR_CE : 0;
165 		if (txx9_priv->cs >= 0 && (ctrl & NAND_NCE)) {
166 			mcr &= ~TXX9_NDFMCR_CS_MASK;
167 			mcr |= TXX9_NDFMCR_CS(txx9_priv->cs);
168 		}
169 		txx9ndfmc_write(dev, mcr, TXX9_NDFMCR);
170 	}
171 	if (cmd != NAND_CMD_NONE)
172 		txx9ndfmc_write(dev, cmd & 0xff, TXX9_NDFDTR);
173 	if (plat->flags & NDFMC_PLAT_FLAG_DUMMYWRITE) {
174 		/* dummy write to update external latch */
175 		if ((ctrl & NAND_CTRL_CHANGE) && cmd == NAND_CMD_NONE)
176 			txx9ndfmc_write(dev, 0, TXX9_NDFDTR);
177 	}
178 	mmiowb();
179 }
180 
txx9ndfmc_dev_ready(struct mtd_info * mtd)181 static int txx9ndfmc_dev_ready(struct mtd_info *mtd)
182 {
183 	struct platform_device *dev = mtd_to_platdev(mtd);
184 
185 	return !(txx9ndfmc_read(dev, TXX9_NDFSR) & TXX9_NDFSR_BUSY);
186 }
187 
txx9ndfmc_calculate_ecc(struct mtd_info * mtd,const uint8_t * dat,uint8_t * ecc_code)188 static int txx9ndfmc_calculate_ecc(struct mtd_info *mtd, const uint8_t *dat,
189 				   uint8_t *ecc_code)
190 {
191 	struct platform_device *dev = mtd_to_platdev(mtd);
192 	struct nand_chip *chip = mtd->priv;
193 	int eccbytes;
194 	u32 mcr = txx9ndfmc_read(dev, TXX9_NDFMCR);
195 
196 	mcr &= ~TXX9_NDFMCR_ECC_ALL;
197 	txx9ndfmc_write(dev, mcr | TXX9_NDFMCR_ECC_OFF, TXX9_NDFMCR);
198 	txx9ndfmc_write(dev, mcr | TXX9_NDFMCR_ECC_READ, TXX9_NDFMCR);
199 	for (eccbytes = chip->ecc.bytes; eccbytes > 0; eccbytes -= 3) {
200 		ecc_code[1] = txx9ndfmc_read(dev, TXX9_NDFDTR);
201 		ecc_code[0] = txx9ndfmc_read(dev, TXX9_NDFDTR);
202 		ecc_code[2] = txx9ndfmc_read(dev, TXX9_NDFDTR);
203 		ecc_code += 3;
204 	}
205 	txx9ndfmc_write(dev, mcr | TXX9_NDFMCR_ECC_OFF, TXX9_NDFMCR);
206 	return 0;
207 }
208 
txx9ndfmc_correct_data(struct mtd_info * mtd,unsigned char * buf,unsigned char * read_ecc,unsigned char * calc_ecc)209 static int txx9ndfmc_correct_data(struct mtd_info *mtd, unsigned char *buf,
210 		unsigned char *read_ecc, unsigned char *calc_ecc)
211 {
212 	struct nand_chip *chip = mtd->priv;
213 	int eccsize;
214 	int corrected = 0;
215 	int stat;
216 
217 	for (eccsize = chip->ecc.size; eccsize > 0; eccsize -= 256) {
218 		stat = __nand_correct_data(buf, read_ecc, calc_ecc, 256);
219 		if (stat < 0)
220 			return stat;
221 		corrected += stat;
222 		buf += 256;
223 		read_ecc += 3;
224 		calc_ecc += 3;
225 	}
226 	return corrected;
227 }
228 
txx9ndfmc_enable_hwecc(struct mtd_info * mtd,int mode)229 static void txx9ndfmc_enable_hwecc(struct mtd_info *mtd, int mode)
230 {
231 	struct platform_device *dev = mtd_to_platdev(mtd);
232 	u32 mcr = txx9ndfmc_read(dev, TXX9_NDFMCR);
233 
234 	mcr &= ~TXX9_NDFMCR_ECC_ALL;
235 	txx9ndfmc_write(dev, mcr | TXX9_NDFMCR_ECC_RESET, TXX9_NDFMCR);
236 	txx9ndfmc_write(dev, mcr | TXX9_NDFMCR_ECC_OFF, TXX9_NDFMCR);
237 	txx9ndfmc_write(dev, mcr | TXX9_NDFMCR_ECC_ON, TXX9_NDFMCR);
238 }
239 
txx9ndfmc_initialize(struct platform_device * dev)240 static void txx9ndfmc_initialize(struct platform_device *dev)
241 {
242 	struct txx9ndfmc_platform_data *plat = dev->dev.platform_data;
243 	struct txx9ndfmc_drvdata *drvdata = platform_get_drvdata(dev);
244 	int tmout = 100;
245 
246 	if (plat->flags & NDFMC_PLAT_FLAG_NO_RSTR)
247 		; /* no NDFRSTR.  Write to NDFSPR resets the NDFMC. */
248 	else {
249 		/* reset NDFMC */
250 		txx9ndfmc_write(dev,
251 				txx9ndfmc_read(dev, TXX9_NDFRSTR) |
252 				TXX9_NDFRSTR_RST,
253 				TXX9_NDFRSTR);
254 		while (txx9ndfmc_read(dev, TXX9_NDFRSTR) & TXX9_NDFRSTR_RST) {
255 			if (--tmout == 0) {
256 				dev_err(&dev->dev, "reset failed.\n");
257 				break;
258 			}
259 			udelay(1);
260 		}
261 	}
262 	/* setup Hold Time, Strobe Pulse Width */
263 	txx9ndfmc_write(dev, (drvdata->hold << 4) | drvdata->spw, TXX9_NDFSPR);
264 	txx9ndfmc_write(dev,
265 			(plat->flags & NDFMC_PLAT_FLAG_USE_BSPRT) ?
266 			TXX9_NDFMCR_BSPRT : 0, TXX9_NDFMCR);
267 }
268 
269 #define TXX9NDFMC_NS_TO_CYC(gbusclk, ns) \
270 	DIV_ROUND_UP((ns) * DIV_ROUND_UP(gbusclk, 1000), 1000000)
271 
txx9ndfmc_nand_scan(struct mtd_info * mtd)272 static int txx9ndfmc_nand_scan(struct mtd_info *mtd)
273 {
274 	struct nand_chip *chip = mtd->priv;
275 	int ret;
276 
277 	ret = nand_scan_ident(mtd, 1, NULL);
278 	if (!ret) {
279 		if (mtd->writesize >= 512) {
280 			/* Hardware ECC 6 byte ECC per 512 Byte data */
281 			chip->ecc.size = 512;
282 			chip->ecc.bytes = 6;
283 		}
284 		ret = nand_scan_tail(mtd);
285 	}
286 	return ret;
287 }
288 
txx9ndfmc_probe(struct platform_device * dev)289 static int __init txx9ndfmc_probe(struct platform_device *dev)
290 {
291 	struct txx9ndfmc_platform_data *plat = dev->dev.platform_data;
292 #ifdef CONFIG_MTD_PARTITIONS
293 	static const char *probes[] = { "cmdlinepart", NULL };
294 #endif
295 	int hold, spw;
296 	int i;
297 	struct txx9ndfmc_drvdata *drvdata;
298 	unsigned long gbusclk = plat->gbus_clock;
299 	struct resource *res;
300 
301 	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
302 	if (!res)
303 		return -ENODEV;
304 	drvdata = devm_kzalloc(&dev->dev, sizeof(*drvdata), GFP_KERNEL);
305 	if (!drvdata)
306 		return -ENOMEM;
307 	if (!devm_request_mem_region(&dev->dev, res->start,
308 				     resource_size(res), dev_name(&dev->dev)))
309 		return -EBUSY;
310 	drvdata->base = devm_ioremap(&dev->dev, res->start,
311 				     resource_size(res));
312 	if (!drvdata->base)
313 		return -EBUSY;
314 
315 	hold = plat->hold ?: 20; /* tDH */
316 	spw = plat->spw ?: 90; /* max(tREADID, tWP, tRP) */
317 
318 	hold = TXX9NDFMC_NS_TO_CYC(gbusclk, hold);
319 	spw = TXX9NDFMC_NS_TO_CYC(gbusclk, spw);
320 	if (plat->flags & NDFMC_PLAT_FLAG_HOLDADD)
321 		hold -= 2;	/* actual hold time : (HOLD + 2) BUSCLK */
322 	spw -= 1;	/* actual wait time : (SPW + 1) BUSCLK */
323 	hold = clamp(hold, 1, 15);
324 	drvdata->hold = hold;
325 	spw = clamp(spw, 1, 15);
326 	drvdata->spw = spw;
327 	dev_info(&dev->dev, "CLK:%ldMHz HOLD:%d SPW:%d\n",
328 		 (gbusclk + 500000) / 1000000, hold, spw);
329 
330 	spin_lock_init(&drvdata->hw_control.lock);
331 	init_waitqueue_head(&drvdata->hw_control.wq);
332 
333 	platform_set_drvdata(dev, drvdata);
334 	txx9ndfmc_initialize(dev);
335 
336 	for (i = 0; i < MAX_TXX9NDFMC_DEV; i++) {
337 		struct txx9ndfmc_priv *txx9_priv;
338 		struct nand_chip *chip;
339 		struct mtd_info *mtd;
340 #ifdef CONFIG_MTD_PARTITIONS
341 		int nr_parts;
342 #endif
343 
344 		if (!(plat->ch_mask & (1 << i)))
345 			continue;
346 		txx9_priv = kzalloc(sizeof(struct txx9ndfmc_priv),
347 				    GFP_KERNEL);
348 		if (!txx9_priv) {
349 			dev_err(&dev->dev, "Unable to allocate "
350 				"TXx9 NDFMC MTD device structure.\n");
351 			continue;
352 		}
353 		chip = &txx9_priv->chip;
354 		mtd = &txx9_priv->mtd;
355 		mtd->owner = THIS_MODULE;
356 
357 		mtd->priv = chip;
358 
359 		chip->read_byte = txx9ndfmc_read_byte;
360 		chip->read_buf = txx9ndfmc_read_buf;
361 		chip->write_buf = txx9ndfmc_write_buf;
362 		chip->verify_buf = txx9ndfmc_verify_buf;
363 		chip->cmd_ctrl = txx9ndfmc_cmd_ctrl;
364 		chip->dev_ready = txx9ndfmc_dev_ready;
365 		chip->ecc.calculate = txx9ndfmc_calculate_ecc;
366 		chip->ecc.correct = txx9ndfmc_correct_data;
367 		chip->ecc.hwctl = txx9ndfmc_enable_hwecc;
368 		chip->ecc.mode = NAND_ECC_HW;
369 		/* txx9ndfmc_nand_scan will overwrite ecc.size and ecc.bytes */
370 		chip->ecc.size = 256;
371 		chip->ecc.bytes = 3;
372 		chip->chip_delay = 100;
373 		chip->controller = &drvdata->hw_control;
374 
375 		chip->priv = txx9_priv;
376 		txx9_priv->dev = dev;
377 
378 		if (plat->ch_mask != 1) {
379 			txx9_priv->cs = i;
380 			txx9_priv->mtdname = kasprintf(GFP_KERNEL, "%s.%u",
381 						       dev_name(&dev->dev), i);
382 		} else {
383 			txx9_priv->cs = -1;
384 			txx9_priv->mtdname = kstrdup(dev_name(&dev->dev),
385 						     GFP_KERNEL);
386 		}
387 		if (!txx9_priv->mtdname) {
388 			kfree(txx9_priv);
389 			dev_err(&dev->dev, "Unable to allocate MTD name.\n");
390 			continue;
391 		}
392 		if (plat->wide_mask & (1 << i))
393 			chip->options |= NAND_BUSWIDTH_16;
394 
395 		if (txx9ndfmc_nand_scan(mtd)) {
396 			kfree(txx9_priv->mtdname);
397 			kfree(txx9_priv);
398 			continue;
399 		}
400 		mtd->name = txx9_priv->mtdname;
401 
402 #ifdef CONFIG_MTD_PARTITIONS
403 		nr_parts = parse_mtd_partitions(mtd, probes,
404 						&drvdata->parts[i], 0);
405 		if (nr_parts > 0)
406 			add_mtd_partitions(mtd, drvdata->parts[i], nr_parts);
407 #endif
408 		add_mtd_device(mtd);
409 		drvdata->mtds[i] = mtd;
410 	}
411 
412 	return 0;
413 }
414 
txx9ndfmc_remove(struct platform_device * dev)415 static int __exit txx9ndfmc_remove(struct platform_device *dev)
416 {
417 	struct txx9ndfmc_drvdata *drvdata = platform_get_drvdata(dev);
418 	int i;
419 
420 	platform_set_drvdata(dev, NULL);
421 	if (!drvdata)
422 		return 0;
423 	for (i = 0; i < MAX_TXX9NDFMC_DEV; i++) {
424 		struct mtd_info *mtd = drvdata->mtds[i];
425 		struct nand_chip *chip;
426 		struct txx9ndfmc_priv *txx9_priv;
427 
428 		if (!mtd)
429 			continue;
430 		chip = mtd->priv;
431 		txx9_priv = chip->priv;
432 
433 		nand_release(mtd);
434 #ifdef CONFIG_MTD_PARTITIONS
435 		kfree(drvdata->parts[i]);
436 #endif
437 		kfree(txx9_priv->mtdname);
438 		kfree(txx9_priv);
439 	}
440 	return 0;
441 }
442 
443 #ifdef CONFIG_PM
txx9ndfmc_resume(struct platform_device * dev)444 static int txx9ndfmc_resume(struct platform_device *dev)
445 {
446 	if (platform_get_drvdata(dev))
447 		txx9ndfmc_initialize(dev);
448 	return 0;
449 }
450 #else
451 #define txx9ndfmc_resume NULL
452 #endif
453 
454 static struct platform_driver txx9ndfmc_driver = {
455 	.remove		= __exit_p(txx9ndfmc_remove),
456 	.resume		= txx9ndfmc_resume,
457 	.driver		= {
458 		.name	= "txx9ndfmc",
459 		.owner	= THIS_MODULE,
460 	},
461 };
462 
txx9ndfmc_init(void)463 static int __init txx9ndfmc_init(void)
464 {
465 	return platform_driver_probe(&txx9ndfmc_driver, txx9ndfmc_probe);
466 }
467 
txx9ndfmc_exit(void)468 static void __exit txx9ndfmc_exit(void)
469 {
470 	platform_driver_unregister(&txx9ndfmc_driver);
471 }
472 
473 module_init(txx9ndfmc_init);
474 module_exit(txx9ndfmc_exit);
475 
476 MODULE_LICENSE("GPL");
477 MODULE_DESCRIPTION("TXx9 SoC NAND flash controller driver");
478 MODULE_ALIAS("platform:txx9ndfmc");
479