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 };
78 
mtd_to_platdev(struct mtd_info * mtd)79 static struct platform_device *mtd_to_platdev(struct mtd_info *mtd)
80 {
81 	struct nand_chip *chip = mtd->priv;
82 	struct txx9ndfmc_priv *txx9_priv = chip->priv;
83 	return txx9_priv->dev;
84 }
85 
ndregaddr(struct platform_device * dev,unsigned int reg)86 static void __iomem *ndregaddr(struct platform_device *dev, unsigned int reg)
87 {
88 	struct txx9ndfmc_drvdata *drvdata = platform_get_drvdata(dev);
89 	struct txx9ndfmc_platform_data *plat = dev->dev.platform_data;
90 
91 	return drvdata->base + (reg << plat->shift);
92 }
93 
txx9ndfmc_read(struct platform_device * dev,unsigned int reg)94 static u32 txx9ndfmc_read(struct platform_device *dev, unsigned int reg)
95 {
96 	return __raw_readl(ndregaddr(dev, reg));
97 }
98 
txx9ndfmc_write(struct platform_device * dev,u32 val,unsigned int reg)99 static void txx9ndfmc_write(struct platform_device *dev,
100 			    u32 val, unsigned int reg)
101 {
102 	__raw_writel(val, ndregaddr(dev, reg));
103 }
104 
txx9ndfmc_read_byte(struct mtd_info * mtd)105 static uint8_t txx9ndfmc_read_byte(struct mtd_info *mtd)
106 {
107 	struct platform_device *dev = mtd_to_platdev(mtd);
108 
109 	return txx9ndfmc_read(dev, TXX9_NDFDTR);
110 }
111 
txx9ndfmc_write_buf(struct mtd_info * mtd,const uint8_t * buf,int len)112 static void txx9ndfmc_write_buf(struct mtd_info *mtd, const uint8_t *buf,
113 				int len)
114 {
115 	struct platform_device *dev = mtd_to_platdev(mtd);
116 	void __iomem *ndfdtr = ndregaddr(dev, TXX9_NDFDTR);
117 	u32 mcr = txx9ndfmc_read(dev, TXX9_NDFMCR);
118 
119 	txx9ndfmc_write(dev, mcr | TXX9_NDFMCR_WE, TXX9_NDFMCR);
120 	while (len--)
121 		__raw_writel(*buf++, ndfdtr);
122 	txx9ndfmc_write(dev, mcr, TXX9_NDFMCR);
123 }
124 
txx9ndfmc_read_buf(struct mtd_info * mtd,uint8_t * buf,int len)125 static void txx9ndfmc_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
126 {
127 	struct platform_device *dev = mtd_to_platdev(mtd);
128 	void __iomem *ndfdtr = ndregaddr(dev, TXX9_NDFDTR);
129 
130 	while (len--)
131 		*buf++ = __raw_readl(ndfdtr);
132 }
133 
txx9ndfmc_verify_buf(struct mtd_info * mtd,const uint8_t * buf,int len)134 static int txx9ndfmc_verify_buf(struct mtd_info *mtd, const uint8_t *buf,
135 				int len)
136 {
137 	struct platform_device *dev = mtd_to_platdev(mtd);
138 	void __iomem *ndfdtr = ndregaddr(dev, TXX9_NDFDTR);
139 
140 	while (len--)
141 		if (*buf++ != (uint8_t)__raw_readl(ndfdtr))
142 			return -EFAULT;
143 	return 0;
144 }
145 
txx9ndfmc_cmd_ctrl(struct mtd_info * mtd,int cmd,unsigned int ctrl)146 static void txx9ndfmc_cmd_ctrl(struct mtd_info *mtd, int cmd,
147 			       unsigned int ctrl)
148 {
149 	struct nand_chip *chip = mtd->priv;
150 	struct txx9ndfmc_priv *txx9_priv = chip->priv;
151 	struct platform_device *dev = txx9_priv->dev;
152 	struct txx9ndfmc_platform_data *plat = dev->dev.platform_data;
153 
154 	if (ctrl & NAND_CTRL_CHANGE) {
155 		u32 mcr = txx9ndfmc_read(dev, TXX9_NDFMCR);
156 
157 		mcr &= ~(TXX9_NDFMCR_CLE | TXX9_NDFMCR_ALE | TXX9_NDFMCR_CE);
158 		mcr |= ctrl & NAND_CLE ? TXX9_NDFMCR_CLE : 0;
159 		mcr |= ctrl & NAND_ALE ? TXX9_NDFMCR_ALE : 0;
160 		/* TXX9_NDFMCR_CE bit is 0:high 1:low */
161 		mcr |= ctrl & NAND_NCE ? TXX9_NDFMCR_CE : 0;
162 		if (txx9_priv->cs >= 0 && (ctrl & NAND_NCE)) {
163 			mcr &= ~TXX9_NDFMCR_CS_MASK;
164 			mcr |= TXX9_NDFMCR_CS(txx9_priv->cs);
165 		}
166 		txx9ndfmc_write(dev, mcr, TXX9_NDFMCR);
167 	}
168 	if (cmd != NAND_CMD_NONE)
169 		txx9ndfmc_write(dev, cmd & 0xff, TXX9_NDFDTR);
170 	if (plat->flags & NDFMC_PLAT_FLAG_DUMMYWRITE) {
171 		/* dummy write to update external latch */
172 		if ((ctrl & NAND_CTRL_CHANGE) && cmd == NAND_CMD_NONE)
173 			txx9ndfmc_write(dev, 0, TXX9_NDFDTR);
174 	}
175 	mmiowb();
176 }
177 
txx9ndfmc_dev_ready(struct mtd_info * mtd)178 static int txx9ndfmc_dev_ready(struct mtd_info *mtd)
179 {
180 	struct platform_device *dev = mtd_to_platdev(mtd);
181 
182 	return !(txx9ndfmc_read(dev, TXX9_NDFSR) & TXX9_NDFSR_BUSY);
183 }
184 
txx9ndfmc_calculate_ecc(struct mtd_info * mtd,const uint8_t * dat,uint8_t * ecc_code)185 static int txx9ndfmc_calculate_ecc(struct mtd_info *mtd, const uint8_t *dat,
186 				   uint8_t *ecc_code)
187 {
188 	struct platform_device *dev = mtd_to_platdev(mtd);
189 	struct nand_chip *chip = mtd->priv;
190 	int eccbytes;
191 	u32 mcr = txx9ndfmc_read(dev, TXX9_NDFMCR);
192 
193 	mcr &= ~TXX9_NDFMCR_ECC_ALL;
194 	txx9ndfmc_write(dev, mcr | TXX9_NDFMCR_ECC_OFF, TXX9_NDFMCR);
195 	txx9ndfmc_write(dev, mcr | TXX9_NDFMCR_ECC_READ, TXX9_NDFMCR);
196 	for (eccbytes = chip->ecc.bytes; eccbytes > 0; eccbytes -= 3) {
197 		ecc_code[1] = txx9ndfmc_read(dev, TXX9_NDFDTR);
198 		ecc_code[0] = txx9ndfmc_read(dev, TXX9_NDFDTR);
199 		ecc_code[2] = txx9ndfmc_read(dev, TXX9_NDFDTR);
200 		ecc_code += 3;
201 	}
202 	txx9ndfmc_write(dev, mcr | TXX9_NDFMCR_ECC_OFF, TXX9_NDFMCR);
203 	return 0;
204 }
205 
txx9ndfmc_correct_data(struct mtd_info * mtd,unsigned char * buf,unsigned char * read_ecc,unsigned char * calc_ecc)206 static int txx9ndfmc_correct_data(struct mtd_info *mtd, unsigned char *buf,
207 		unsigned char *read_ecc, unsigned char *calc_ecc)
208 {
209 	struct nand_chip *chip = mtd->priv;
210 	int eccsize;
211 	int corrected = 0;
212 	int stat;
213 
214 	for (eccsize = chip->ecc.size; eccsize > 0; eccsize -= 256) {
215 		stat = __nand_correct_data(buf, read_ecc, calc_ecc, 256);
216 		if (stat < 0)
217 			return stat;
218 		corrected += stat;
219 		buf += 256;
220 		read_ecc += 3;
221 		calc_ecc += 3;
222 	}
223 	return corrected;
224 }
225 
txx9ndfmc_enable_hwecc(struct mtd_info * mtd,int mode)226 static void txx9ndfmc_enable_hwecc(struct mtd_info *mtd, int mode)
227 {
228 	struct platform_device *dev = mtd_to_platdev(mtd);
229 	u32 mcr = txx9ndfmc_read(dev, TXX9_NDFMCR);
230 
231 	mcr &= ~TXX9_NDFMCR_ECC_ALL;
232 	txx9ndfmc_write(dev, mcr | TXX9_NDFMCR_ECC_RESET, TXX9_NDFMCR);
233 	txx9ndfmc_write(dev, mcr | TXX9_NDFMCR_ECC_OFF, TXX9_NDFMCR);
234 	txx9ndfmc_write(dev, mcr | TXX9_NDFMCR_ECC_ON, TXX9_NDFMCR);
235 }
236 
txx9ndfmc_initialize(struct platform_device * dev)237 static void txx9ndfmc_initialize(struct platform_device *dev)
238 {
239 	struct txx9ndfmc_platform_data *plat = dev->dev.platform_data;
240 	struct txx9ndfmc_drvdata *drvdata = platform_get_drvdata(dev);
241 	int tmout = 100;
242 
243 	if (plat->flags & NDFMC_PLAT_FLAG_NO_RSTR)
244 		; /* no NDFRSTR.  Write to NDFSPR resets the NDFMC. */
245 	else {
246 		/* reset NDFMC */
247 		txx9ndfmc_write(dev,
248 				txx9ndfmc_read(dev, TXX9_NDFRSTR) |
249 				TXX9_NDFRSTR_RST,
250 				TXX9_NDFRSTR);
251 		while (txx9ndfmc_read(dev, TXX9_NDFRSTR) & TXX9_NDFRSTR_RST) {
252 			if (--tmout == 0) {
253 				dev_err(&dev->dev, "reset failed.\n");
254 				break;
255 			}
256 			udelay(1);
257 		}
258 	}
259 	/* setup Hold Time, Strobe Pulse Width */
260 	txx9ndfmc_write(dev, (drvdata->hold << 4) | drvdata->spw, TXX9_NDFSPR);
261 	txx9ndfmc_write(dev,
262 			(plat->flags & NDFMC_PLAT_FLAG_USE_BSPRT) ?
263 			TXX9_NDFMCR_BSPRT : 0, TXX9_NDFMCR);
264 }
265 
266 #define TXX9NDFMC_NS_TO_CYC(gbusclk, ns) \
267 	DIV_ROUND_UP((ns) * DIV_ROUND_UP(gbusclk, 1000), 1000000)
268 
txx9ndfmc_nand_scan(struct mtd_info * mtd)269 static int txx9ndfmc_nand_scan(struct mtd_info *mtd)
270 {
271 	struct nand_chip *chip = mtd->priv;
272 	int ret;
273 
274 	ret = nand_scan_ident(mtd, 1, NULL);
275 	if (!ret) {
276 		if (mtd->writesize >= 512) {
277 			/* Hardware ECC 6 byte ECC per 512 Byte data */
278 			chip->ecc.size = 512;
279 			chip->ecc.bytes = 6;
280 		}
281 		ret = nand_scan_tail(mtd);
282 	}
283 	return ret;
284 }
285 
txx9ndfmc_probe(struct platform_device * dev)286 static int __init txx9ndfmc_probe(struct platform_device *dev)
287 {
288 	struct txx9ndfmc_platform_data *plat = dev->dev.platform_data;
289 	int hold, spw;
290 	int i;
291 	struct txx9ndfmc_drvdata *drvdata;
292 	unsigned long gbusclk = plat->gbus_clock;
293 	struct resource *res;
294 
295 	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
296 	if (!res)
297 		return -ENODEV;
298 	drvdata = devm_kzalloc(&dev->dev, sizeof(*drvdata), GFP_KERNEL);
299 	if (!drvdata)
300 		return -ENOMEM;
301 	drvdata->base = devm_request_and_ioremap(&dev->dev, res);
302 	if (!drvdata->base)
303 		return -EBUSY;
304 
305 	hold = plat->hold ?: 20; /* tDH */
306 	spw = plat->spw ?: 90; /* max(tREADID, tWP, tRP) */
307 
308 	hold = TXX9NDFMC_NS_TO_CYC(gbusclk, hold);
309 	spw = TXX9NDFMC_NS_TO_CYC(gbusclk, spw);
310 	if (plat->flags & NDFMC_PLAT_FLAG_HOLDADD)
311 		hold -= 2;	/* actual hold time : (HOLD + 2) BUSCLK */
312 	spw -= 1;	/* actual wait time : (SPW + 1) BUSCLK */
313 	hold = clamp(hold, 1, 15);
314 	drvdata->hold = hold;
315 	spw = clamp(spw, 1, 15);
316 	drvdata->spw = spw;
317 	dev_info(&dev->dev, "CLK:%ldMHz HOLD:%d SPW:%d\n",
318 		 (gbusclk + 500000) / 1000000, hold, spw);
319 
320 	spin_lock_init(&drvdata->hw_control.lock);
321 	init_waitqueue_head(&drvdata->hw_control.wq);
322 
323 	platform_set_drvdata(dev, drvdata);
324 	txx9ndfmc_initialize(dev);
325 
326 	for (i = 0; i < MAX_TXX9NDFMC_DEV; i++) {
327 		struct txx9ndfmc_priv *txx9_priv;
328 		struct nand_chip *chip;
329 		struct mtd_info *mtd;
330 
331 		if (!(plat->ch_mask & (1 << i)))
332 			continue;
333 		txx9_priv = kzalloc(sizeof(struct txx9ndfmc_priv),
334 				    GFP_KERNEL);
335 		if (!txx9_priv) {
336 			dev_err(&dev->dev, "Unable to allocate "
337 				"TXx9 NDFMC MTD device structure.\n");
338 			continue;
339 		}
340 		chip = &txx9_priv->chip;
341 		mtd = &txx9_priv->mtd;
342 		mtd->owner = THIS_MODULE;
343 
344 		mtd->priv = chip;
345 
346 		chip->read_byte = txx9ndfmc_read_byte;
347 		chip->read_buf = txx9ndfmc_read_buf;
348 		chip->write_buf = txx9ndfmc_write_buf;
349 		chip->verify_buf = txx9ndfmc_verify_buf;
350 		chip->cmd_ctrl = txx9ndfmc_cmd_ctrl;
351 		chip->dev_ready = txx9ndfmc_dev_ready;
352 		chip->ecc.calculate = txx9ndfmc_calculate_ecc;
353 		chip->ecc.correct = txx9ndfmc_correct_data;
354 		chip->ecc.hwctl = txx9ndfmc_enable_hwecc;
355 		chip->ecc.mode = NAND_ECC_HW;
356 		/* txx9ndfmc_nand_scan will overwrite ecc.size and ecc.bytes */
357 		chip->ecc.size = 256;
358 		chip->ecc.bytes = 3;
359 		chip->chip_delay = 100;
360 		chip->controller = &drvdata->hw_control;
361 
362 		chip->priv = txx9_priv;
363 		txx9_priv->dev = dev;
364 
365 		if (plat->ch_mask != 1) {
366 			txx9_priv->cs = i;
367 			txx9_priv->mtdname = kasprintf(GFP_KERNEL, "%s.%u",
368 						       dev_name(&dev->dev), i);
369 		} else {
370 			txx9_priv->cs = -1;
371 			txx9_priv->mtdname = kstrdup(dev_name(&dev->dev),
372 						     GFP_KERNEL);
373 		}
374 		if (!txx9_priv->mtdname) {
375 			kfree(txx9_priv);
376 			dev_err(&dev->dev, "Unable to allocate MTD name.\n");
377 			continue;
378 		}
379 		if (plat->wide_mask & (1 << i))
380 			chip->options |= NAND_BUSWIDTH_16;
381 
382 		if (txx9ndfmc_nand_scan(mtd)) {
383 			kfree(txx9_priv->mtdname);
384 			kfree(txx9_priv);
385 			continue;
386 		}
387 		mtd->name = txx9_priv->mtdname;
388 
389 		mtd_device_parse_register(mtd, NULL, 0, NULL, 0);
390 		drvdata->mtds[i] = mtd;
391 	}
392 
393 	return 0;
394 }
395 
txx9ndfmc_remove(struct platform_device * dev)396 static int __exit txx9ndfmc_remove(struct platform_device *dev)
397 {
398 	struct txx9ndfmc_drvdata *drvdata = platform_get_drvdata(dev);
399 	int i;
400 
401 	platform_set_drvdata(dev, NULL);
402 	if (!drvdata)
403 		return 0;
404 	for (i = 0; i < MAX_TXX9NDFMC_DEV; i++) {
405 		struct mtd_info *mtd = drvdata->mtds[i];
406 		struct nand_chip *chip;
407 		struct txx9ndfmc_priv *txx9_priv;
408 
409 		if (!mtd)
410 			continue;
411 		chip = mtd->priv;
412 		txx9_priv = chip->priv;
413 
414 		nand_release(mtd);
415 		kfree(txx9_priv->mtdname);
416 		kfree(txx9_priv);
417 	}
418 	return 0;
419 }
420 
421 #ifdef CONFIG_PM
txx9ndfmc_resume(struct platform_device * dev)422 static int txx9ndfmc_resume(struct platform_device *dev)
423 {
424 	if (platform_get_drvdata(dev))
425 		txx9ndfmc_initialize(dev);
426 	return 0;
427 }
428 #else
429 #define txx9ndfmc_resume NULL
430 #endif
431 
432 static struct platform_driver txx9ndfmc_driver = {
433 	.remove		= __exit_p(txx9ndfmc_remove),
434 	.resume		= txx9ndfmc_resume,
435 	.driver		= {
436 		.name	= "txx9ndfmc",
437 		.owner	= THIS_MODULE,
438 	},
439 };
440 
txx9ndfmc_init(void)441 static int __init txx9ndfmc_init(void)
442 {
443 	return platform_driver_probe(&txx9ndfmc_driver, txx9ndfmc_probe);
444 }
445 
txx9ndfmc_exit(void)446 static void __exit txx9ndfmc_exit(void)
447 {
448 	platform_driver_unregister(&txx9ndfmc_driver);
449 }
450 
451 module_init(txx9ndfmc_init);
452 module_exit(txx9ndfmc_exit);
453 
454 MODULE_LICENSE("GPL");
455 MODULE_DESCRIPTION("TXx9 SoC NAND flash controller driver");
456 MODULE_ALIAS("platform:txx9ndfmc");
457