xref: /openbmc/linux/drivers/mtd/nand/raw/txx9ndfmc.c (revision 67559900)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * TXx9 NAND flash memory controller driver
4  * Based on RBTX49xx patch from CELF patch archive.
5  *
6  * (C) Copyright TOSHIBA CORPORATION 2004-2007
7  * All Rights Reserved.
8  */
9 #include <linux/err.h>
10 #include <linux/init.h>
11 #include <linux/slab.h>
12 #include <linux/module.h>
13 #include <linux/platform_device.h>
14 #include <linux/delay.h>
15 #include <linux/mtd/mtd.h>
16 #include <linux/mtd/rawnand.h>
17 #include <linux/mtd/partitions.h>
18 #include <linux/io.h>
19 #include <linux/platform_data/txx9/ndfmc.h>
20 
21 /* TXX9 NDFMC Registers */
22 #define TXX9_NDFDTR	0x00
23 #define TXX9_NDFMCR	0x04
24 #define TXX9_NDFSR	0x08
25 #define TXX9_NDFISR	0x0c
26 #define TXX9_NDFIMR	0x10
27 #define TXX9_NDFSPR	0x14
28 #define TXX9_NDFRSTR	0x18	/* not TX4939 */
29 
30 /* NDFMCR : NDFMC Mode Control */
31 #define TXX9_NDFMCR_WE	0x80
32 #define TXX9_NDFMCR_ECC_ALL	0x60
33 #define TXX9_NDFMCR_ECC_RESET	0x60
34 #define TXX9_NDFMCR_ECC_READ	0x40
35 #define TXX9_NDFMCR_ECC_ON	0x20
36 #define TXX9_NDFMCR_ECC_OFF	0x00
37 #define TXX9_NDFMCR_CE	0x10
38 #define TXX9_NDFMCR_BSPRT	0x04	/* TX4925/TX4926 only */
39 #define TXX9_NDFMCR_ALE	0x02
40 #define TXX9_NDFMCR_CLE	0x01
41 /* TX4939 only */
42 #define TXX9_NDFMCR_X16	0x0400
43 #define TXX9_NDFMCR_DMAREQ_MASK	0x0300
44 #define TXX9_NDFMCR_DMAREQ_NODMA	0x0000
45 #define TXX9_NDFMCR_DMAREQ_128	0x0100
46 #define TXX9_NDFMCR_DMAREQ_256	0x0200
47 #define TXX9_NDFMCR_DMAREQ_512	0x0300
48 #define TXX9_NDFMCR_CS_MASK	0x0c
49 #define TXX9_NDFMCR_CS(ch)	((ch) << 2)
50 
51 /* NDFMCR : NDFMC Status */
52 #define TXX9_NDFSR_BUSY	0x80
53 /* TX4939 only */
54 #define TXX9_NDFSR_DMARUN	0x40
55 
56 /* NDFMCR : NDFMC Reset */
57 #define TXX9_NDFRSTR_RST	0x01
58 
59 struct txx9ndfmc_priv {
60 	struct platform_device *dev;
61 	struct nand_chip chip;
62 	int cs;
63 	const char *mtdname;
64 };
65 
66 #define MAX_TXX9NDFMC_DEV	4
67 struct txx9ndfmc_drvdata {
68 	struct mtd_info *mtds[MAX_TXX9NDFMC_DEV];
69 	void __iomem *base;
70 	unsigned char hold;	/* in gbusclock */
71 	unsigned char spw;	/* in gbusclock */
72 	struct nand_controller controller;
73 };
74 
75 static struct platform_device *mtd_to_platdev(struct mtd_info *mtd)
76 {
77 	struct nand_chip *chip = mtd_to_nand(mtd);
78 	struct txx9ndfmc_priv *txx9_priv = nand_get_controller_data(chip);
79 	return txx9_priv->dev;
80 }
81 
82 static void __iomem *ndregaddr(struct platform_device *dev, unsigned int reg)
83 {
84 	struct txx9ndfmc_drvdata *drvdata = platform_get_drvdata(dev);
85 	struct txx9ndfmc_platform_data *plat = dev_get_platdata(&dev->dev);
86 
87 	return drvdata->base + (reg << plat->shift);
88 }
89 
90 static u32 txx9ndfmc_read(struct platform_device *dev, unsigned int reg)
91 {
92 	return __raw_readl(ndregaddr(dev, reg));
93 }
94 
95 static void txx9ndfmc_write(struct platform_device *dev,
96 			    u32 val, unsigned int reg)
97 {
98 	__raw_writel(val, ndregaddr(dev, reg));
99 }
100 
101 static uint8_t txx9ndfmc_read_byte(struct nand_chip *chip)
102 {
103 	struct platform_device *dev = mtd_to_platdev(nand_to_mtd(chip));
104 
105 	return txx9ndfmc_read(dev, TXX9_NDFDTR);
106 }
107 
108 static void txx9ndfmc_write_buf(struct nand_chip *chip, const uint8_t *buf,
109 				int len)
110 {
111 	struct platform_device *dev = mtd_to_platdev(nand_to_mtd(chip));
112 	void __iomem *ndfdtr = ndregaddr(dev, TXX9_NDFDTR);
113 	u32 mcr = txx9ndfmc_read(dev, TXX9_NDFMCR);
114 
115 	txx9ndfmc_write(dev, mcr | TXX9_NDFMCR_WE, TXX9_NDFMCR);
116 	while (len--)
117 		__raw_writel(*buf++, ndfdtr);
118 	txx9ndfmc_write(dev, mcr, TXX9_NDFMCR);
119 }
120 
121 static void txx9ndfmc_read_buf(struct nand_chip *chip, uint8_t *buf, int len)
122 {
123 	struct platform_device *dev = mtd_to_platdev(nand_to_mtd(chip));
124 	void __iomem *ndfdtr = ndregaddr(dev, TXX9_NDFDTR);
125 
126 	while (len--)
127 		*buf++ = __raw_readl(ndfdtr);
128 }
129 
130 static void txx9ndfmc_cmd_ctrl(struct nand_chip *chip, int cmd,
131 			       unsigned int ctrl)
132 {
133 	struct txx9ndfmc_priv *txx9_priv = nand_get_controller_data(chip);
134 	struct platform_device *dev = txx9_priv->dev;
135 	struct txx9ndfmc_platform_data *plat = dev_get_platdata(&dev->dev);
136 
137 	if (ctrl & NAND_CTRL_CHANGE) {
138 		u32 mcr = txx9ndfmc_read(dev, TXX9_NDFMCR);
139 
140 		mcr &= ~(TXX9_NDFMCR_CLE | TXX9_NDFMCR_ALE | TXX9_NDFMCR_CE);
141 		mcr |= ctrl & NAND_CLE ? TXX9_NDFMCR_CLE : 0;
142 		mcr |= ctrl & NAND_ALE ? TXX9_NDFMCR_ALE : 0;
143 		/* TXX9_NDFMCR_CE bit is 0:high 1:low */
144 		mcr |= ctrl & NAND_NCE ? TXX9_NDFMCR_CE : 0;
145 		if (txx9_priv->cs >= 0 && (ctrl & NAND_NCE)) {
146 			mcr &= ~TXX9_NDFMCR_CS_MASK;
147 			mcr |= TXX9_NDFMCR_CS(txx9_priv->cs);
148 		}
149 		txx9ndfmc_write(dev, mcr, TXX9_NDFMCR);
150 	}
151 	if (cmd != NAND_CMD_NONE)
152 		txx9ndfmc_write(dev, cmd & 0xff, TXX9_NDFDTR);
153 	if (plat->flags & NDFMC_PLAT_FLAG_DUMMYWRITE) {
154 		/* dummy write to update external latch */
155 		if ((ctrl & NAND_CTRL_CHANGE) && cmd == NAND_CMD_NONE)
156 			txx9ndfmc_write(dev, 0, TXX9_NDFDTR);
157 	}
158 }
159 
160 static int txx9ndfmc_dev_ready(struct nand_chip *chip)
161 {
162 	struct platform_device *dev = mtd_to_platdev(nand_to_mtd(chip));
163 
164 	return !(txx9ndfmc_read(dev, TXX9_NDFSR) & TXX9_NDFSR_BUSY);
165 }
166 
167 static int txx9ndfmc_calculate_ecc(struct nand_chip *chip, const uint8_t *dat,
168 				   uint8_t *ecc_code)
169 {
170 	struct platform_device *dev = mtd_to_platdev(nand_to_mtd(chip));
171 	int eccbytes;
172 	u32 mcr = txx9ndfmc_read(dev, TXX9_NDFMCR);
173 
174 	mcr &= ~TXX9_NDFMCR_ECC_ALL;
175 	txx9ndfmc_write(dev, mcr | TXX9_NDFMCR_ECC_OFF, TXX9_NDFMCR);
176 	txx9ndfmc_write(dev, mcr | TXX9_NDFMCR_ECC_READ, TXX9_NDFMCR);
177 	for (eccbytes = chip->ecc.bytes; eccbytes > 0; eccbytes -= 3) {
178 		ecc_code[1] = txx9ndfmc_read(dev, TXX9_NDFDTR);
179 		ecc_code[0] = txx9ndfmc_read(dev, TXX9_NDFDTR);
180 		ecc_code[2] = txx9ndfmc_read(dev, TXX9_NDFDTR);
181 		ecc_code += 3;
182 	}
183 	txx9ndfmc_write(dev, mcr | TXX9_NDFMCR_ECC_OFF, TXX9_NDFMCR);
184 	return 0;
185 }
186 
187 static int txx9ndfmc_correct_data(struct nand_chip *chip, unsigned char *buf,
188 				  unsigned char *read_ecc,
189 				  unsigned char *calc_ecc)
190 {
191 	int eccsize;
192 	int corrected = 0;
193 	int stat;
194 
195 	for (eccsize = chip->ecc.size; eccsize > 0; eccsize -= 256) {
196 		stat = rawnand_sw_hamming_correct(chip, buf, read_ecc,
197 						  calc_ecc);
198 		if (stat < 0)
199 			return stat;
200 		corrected += stat;
201 		buf += 256;
202 		read_ecc += 3;
203 		calc_ecc += 3;
204 	}
205 	return corrected;
206 }
207 
208 static void txx9ndfmc_enable_hwecc(struct nand_chip *chip, int mode)
209 {
210 	struct platform_device *dev = mtd_to_platdev(nand_to_mtd(chip));
211 	u32 mcr = txx9ndfmc_read(dev, TXX9_NDFMCR);
212 
213 	mcr &= ~TXX9_NDFMCR_ECC_ALL;
214 	txx9ndfmc_write(dev, mcr | TXX9_NDFMCR_ECC_RESET, TXX9_NDFMCR);
215 	txx9ndfmc_write(dev, mcr | TXX9_NDFMCR_ECC_OFF, TXX9_NDFMCR);
216 	txx9ndfmc_write(dev, mcr | TXX9_NDFMCR_ECC_ON, TXX9_NDFMCR);
217 }
218 
219 static void txx9ndfmc_initialize(struct platform_device *dev)
220 {
221 	struct txx9ndfmc_platform_data *plat = dev_get_platdata(&dev->dev);
222 	struct txx9ndfmc_drvdata *drvdata = platform_get_drvdata(dev);
223 	int tmout = 100;
224 
225 	if (plat->flags & NDFMC_PLAT_FLAG_NO_RSTR)
226 		; /* no NDFRSTR.  Write to NDFSPR resets the NDFMC. */
227 	else {
228 		/* reset NDFMC */
229 		txx9ndfmc_write(dev,
230 				txx9ndfmc_read(dev, TXX9_NDFRSTR) |
231 				TXX9_NDFRSTR_RST,
232 				TXX9_NDFRSTR);
233 		while (txx9ndfmc_read(dev, TXX9_NDFRSTR) & TXX9_NDFRSTR_RST) {
234 			if (--tmout == 0) {
235 				dev_err(&dev->dev, "reset failed.\n");
236 				break;
237 			}
238 			udelay(1);
239 		}
240 	}
241 	/* setup Hold Time, Strobe Pulse Width */
242 	txx9ndfmc_write(dev, (drvdata->hold << 4) | drvdata->spw, TXX9_NDFSPR);
243 	txx9ndfmc_write(dev,
244 			(plat->flags & NDFMC_PLAT_FLAG_USE_BSPRT) ?
245 			TXX9_NDFMCR_BSPRT : 0, TXX9_NDFMCR);
246 }
247 
248 #define TXX9NDFMC_NS_TO_CYC(gbusclk, ns) \
249 	DIV_ROUND_UP((ns) * DIV_ROUND_UP(gbusclk, 1000), 1000000)
250 
251 static int txx9ndfmc_attach_chip(struct nand_chip *chip)
252 {
253 	struct mtd_info *mtd = nand_to_mtd(chip);
254 
255 	if (chip->ecc.engine_type != NAND_ECC_ENGINE_TYPE_ON_HOST)
256 		return 0;
257 
258 	chip->ecc.strength = 1;
259 
260 	if (mtd->writesize >= 512) {
261 		chip->ecc.size = 512;
262 		chip->ecc.bytes = 6;
263 	} else {
264 		chip->ecc.size = 256;
265 		chip->ecc.bytes = 3;
266 	}
267 
268 	chip->ecc.calculate = txx9ndfmc_calculate_ecc;
269 	chip->ecc.correct = txx9ndfmc_correct_data;
270 	chip->ecc.hwctl = txx9ndfmc_enable_hwecc;
271 
272 	return 0;
273 }
274 
275 static const struct nand_controller_ops txx9ndfmc_controller_ops = {
276 	.attach_chip = txx9ndfmc_attach_chip,
277 };
278 
279 static int __init txx9ndfmc_probe(struct platform_device *dev)
280 {
281 	struct txx9ndfmc_platform_data *plat = dev_get_platdata(&dev->dev);
282 	int hold, spw;
283 	int i;
284 	struct txx9ndfmc_drvdata *drvdata;
285 	unsigned long gbusclk = plat->gbus_clock;
286 
287 	drvdata = devm_kzalloc(&dev->dev, sizeof(*drvdata), GFP_KERNEL);
288 	if (!drvdata)
289 		return -ENOMEM;
290 	drvdata->base = devm_platform_ioremap_resource(dev, 0);
291 	if (IS_ERR(drvdata->base))
292 		return PTR_ERR(drvdata->base);
293 
294 	hold = plat->hold ?: 20; /* tDH */
295 	spw = plat->spw ?: 90; /* max(tREADID, tWP, tRP) */
296 
297 	hold = TXX9NDFMC_NS_TO_CYC(gbusclk, hold);
298 	spw = TXX9NDFMC_NS_TO_CYC(gbusclk, spw);
299 	if (plat->flags & NDFMC_PLAT_FLAG_HOLDADD)
300 		hold -= 2;	/* actual hold time : (HOLD + 2) BUSCLK */
301 	spw -= 1;	/* actual wait time : (SPW + 1) BUSCLK */
302 	hold = clamp(hold, 1, 15);
303 	drvdata->hold = hold;
304 	spw = clamp(spw, 1, 15);
305 	drvdata->spw = spw;
306 	dev_info(&dev->dev, "CLK:%ldMHz HOLD:%d SPW:%d\n",
307 		 (gbusclk + 500000) / 1000000, hold, spw);
308 
309 	nand_controller_init(&drvdata->controller);
310 	drvdata->controller.ops = &txx9ndfmc_controller_ops;
311 
312 	platform_set_drvdata(dev, drvdata);
313 	txx9ndfmc_initialize(dev);
314 
315 	for (i = 0; i < MAX_TXX9NDFMC_DEV; i++) {
316 		struct txx9ndfmc_priv *txx9_priv;
317 		struct nand_chip *chip;
318 		struct mtd_info *mtd;
319 
320 		if (!(plat->ch_mask & (1 << i)))
321 			continue;
322 		txx9_priv = kzalloc(sizeof(struct txx9ndfmc_priv),
323 				    GFP_KERNEL);
324 		if (!txx9_priv)
325 			continue;
326 		chip = &txx9_priv->chip;
327 		mtd = nand_to_mtd(chip);
328 		mtd->dev.parent = &dev->dev;
329 
330 		chip->legacy.read_byte = txx9ndfmc_read_byte;
331 		chip->legacy.read_buf = txx9ndfmc_read_buf;
332 		chip->legacy.write_buf = txx9ndfmc_write_buf;
333 		chip->legacy.cmd_ctrl = txx9ndfmc_cmd_ctrl;
334 		chip->legacy.dev_ready = txx9ndfmc_dev_ready;
335 		chip->legacy.chip_delay = 100;
336 		chip->controller = &drvdata->controller;
337 
338 		nand_set_controller_data(chip, txx9_priv);
339 		txx9_priv->dev = dev;
340 
341 		if (plat->ch_mask != 1) {
342 			txx9_priv->cs = i;
343 			txx9_priv->mtdname = kasprintf(GFP_KERNEL, "%s.%u",
344 						       dev_name(&dev->dev), i);
345 		} else {
346 			txx9_priv->cs = -1;
347 			txx9_priv->mtdname = kstrdup(dev_name(&dev->dev),
348 						     GFP_KERNEL);
349 		}
350 		if (!txx9_priv->mtdname) {
351 			kfree(txx9_priv);
352 			dev_err(&dev->dev, "Unable to allocate MTD name.\n");
353 			continue;
354 		}
355 		if (plat->wide_mask & (1 << i))
356 			chip->options |= NAND_BUSWIDTH_16;
357 
358 		if (nand_scan(chip, 1)) {
359 			kfree(txx9_priv->mtdname);
360 			kfree(txx9_priv);
361 			continue;
362 		}
363 		mtd->name = txx9_priv->mtdname;
364 
365 		mtd_device_register(mtd, NULL, 0);
366 		drvdata->mtds[i] = mtd;
367 	}
368 
369 	return 0;
370 }
371 
372 static int __exit txx9ndfmc_remove(struct platform_device *dev)
373 {
374 	struct txx9ndfmc_drvdata *drvdata = platform_get_drvdata(dev);
375 	int ret, i;
376 
377 	if (!drvdata)
378 		return 0;
379 	for (i = 0; i < MAX_TXX9NDFMC_DEV; i++) {
380 		struct mtd_info *mtd = drvdata->mtds[i];
381 		struct nand_chip *chip;
382 		struct txx9ndfmc_priv *txx9_priv;
383 
384 		if (!mtd)
385 			continue;
386 		chip = mtd_to_nand(mtd);
387 		txx9_priv = nand_get_controller_data(chip);
388 
389 		ret = mtd_device_unregister(nand_to_mtd(chip));
390 		WARN_ON(ret);
391 		nand_cleanup(chip);
392 		kfree(txx9_priv->mtdname);
393 		kfree(txx9_priv);
394 	}
395 	return 0;
396 }
397 
398 #ifdef CONFIG_PM
399 static int txx9ndfmc_resume(struct platform_device *dev)
400 {
401 	if (platform_get_drvdata(dev))
402 		txx9ndfmc_initialize(dev);
403 	return 0;
404 }
405 #else
406 #define txx9ndfmc_resume NULL
407 #endif
408 
409 static struct platform_driver txx9ndfmc_driver = {
410 	.remove		= __exit_p(txx9ndfmc_remove),
411 	.resume		= txx9ndfmc_resume,
412 	.driver		= {
413 		.name	= "txx9ndfmc",
414 	},
415 };
416 
417 module_platform_driver_probe(txx9ndfmc_driver, txx9ndfmc_probe);
418 
419 MODULE_LICENSE("GPL");
420 MODULE_DESCRIPTION("TXx9 SoC NAND flash controller driver");
421 MODULE_ALIAS("platform:txx9ndfmc");
422