xref: /openbmc/linux/drivers/mtd/nand/raw/txx9ndfmc.c (revision 4eb5928d)
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/nand_ecc.h>
18 #include <linux/mtd/partitions.h>
19 #include <linux/io.h>
20 #include <linux/platform_data/txx9/ndfmc.h>
21 
22 /* TXX9 NDFMC Registers */
23 #define TXX9_NDFDTR	0x00
24 #define TXX9_NDFMCR	0x04
25 #define TXX9_NDFSR	0x08
26 #define TXX9_NDFISR	0x0c
27 #define TXX9_NDFIMR	0x10
28 #define TXX9_NDFSPR	0x14
29 #define TXX9_NDFRSTR	0x18	/* not TX4939 */
30 
31 /* NDFMCR : NDFMC Mode Control */
32 #define TXX9_NDFMCR_WE	0x80
33 #define TXX9_NDFMCR_ECC_ALL	0x60
34 #define TXX9_NDFMCR_ECC_RESET	0x60
35 #define TXX9_NDFMCR_ECC_READ	0x40
36 #define TXX9_NDFMCR_ECC_ON	0x20
37 #define TXX9_NDFMCR_ECC_OFF	0x00
38 #define TXX9_NDFMCR_CE	0x10
39 #define TXX9_NDFMCR_BSPRT	0x04	/* TX4925/TX4926 only */
40 #define TXX9_NDFMCR_ALE	0x02
41 #define TXX9_NDFMCR_CLE	0x01
42 /* TX4939 only */
43 #define TXX9_NDFMCR_X16	0x0400
44 #define TXX9_NDFMCR_DMAREQ_MASK	0x0300
45 #define TXX9_NDFMCR_DMAREQ_NODMA	0x0000
46 #define TXX9_NDFMCR_DMAREQ_128	0x0100
47 #define TXX9_NDFMCR_DMAREQ_256	0x0200
48 #define TXX9_NDFMCR_DMAREQ_512	0x0300
49 #define TXX9_NDFMCR_CS_MASK	0x0c
50 #define TXX9_NDFMCR_CS(ch)	((ch) << 2)
51 
52 /* NDFMCR : NDFMC Status */
53 #define TXX9_NDFSR_BUSY	0x80
54 /* TX4939 only */
55 #define TXX9_NDFSR_DMARUN	0x40
56 
57 /* NDFMCR : NDFMC Reset */
58 #define TXX9_NDFRSTR_RST	0x01
59 
60 struct txx9ndfmc_priv {
61 	struct platform_device *dev;
62 	struct nand_chip chip;
63 	int cs;
64 	const char *mtdname;
65 };
66 
67 #define MAX_TXX9NDFMC_DEV	4
68 struct txx9ndfmc_drvdata {
69 	struct mtd_info *mtds[MAX_TXX9NDFMC_DEV];
70 	void __iomem *base;
71 	unsigned char hold;	/* in gbusclock */
72 	unsigned char spw;	/* in gbusclock */
73 	struct nand_controller controller;
74 };
75 
76 static struct platform_device *mtd_to_platdev(struct mtd_info *mtd)
77 {
78 	struct nand_chip *chip = mtd_to_nand(mtd);
79 	struct txx9ndfmc_priv *txx9_priv = nand_get_controller_data(chip);
80 	return txx9_priv->dev;
81 }
82 
83 static void __iomem *ndregaddr(struct platform_device *dev, unsigned int reg)
84 {
85 	struct txx9ndfmc_drvdata *drvdata = platform_get_drvdata(dev);
86 	struct txx9ndfmc_platform_data *plat = dev_get_platdata(&dev->dev);
87 
88 	return drvdata->base + (reg << plat->shift);
89 }
90 
91 static u32 txx9ndfmc_read(struct platform_device *dev, unsigned int reg)
92 {
93 	return __raw_readl(ndregaddr(dev, reg));
94 }
95 
96 static void txx9ndfmc_write(struct platform_device *dev,
97 			    u32 val, unsigned int reg)
98 {
99 	__raw_writel(val, ndregaddr(dev, reg));
100 }
101 
102 static uint8_t txx9ndfmc_read_byte(struct nand_chip *chip)
103 {
104 	struct platform_device *dev = mtd_to_platdev(nand_to_mtd(chip));
105 
106 	return txx9ndfmc_read(dev, TXX9_NDFDTR);
107 }
108 
109 static void txx9ndfmc_write_buf(struct nand_chip *chip, const uint8_t *buf,
110 				int len)
111 {
112 	struct platform_device *dev = mtd_to_platdev(nand_to_mtd(chip));
113 	void __iomem *ndfdtr = ndregaddr(dev, TXX9_NDFDTR);
114 	u32 mcr = txx9ndfmc_read(dev, TXX9_NDFMCR);
115 
116 	txx9ndfmc_write(dev, mcr | TXX9_NDFMCR_WE, TXX9_NDFMCR);
117 	while (len--)
118 		__raw_writel(*buf++, ndfdtr);
119 	txx9ndfmc_write(dev, mcr, TXX9_NDFMCR);
120 }
121 
122 static void txx9ndfmc_read_buf(struct nand_chip *chip, uint8_t *buf, int len)
123 {
124 	struct platform_device *dev = mtd_to_platdev(nand_to_mtd(chip));
125 	void __iomem *ndfdtr = ndregaddr(dev, TXX9_NDFDTR);
126 
127 	while (len--)
128 		*buf++ = __raw_readl(ndfdtr);
129 }
130 
131 static void txx9ndfmc_cmd_ctrl(struct nand_chip *chip, int cmd,
132 			       unsigned int ctrl)
133 {
134 	struct txx9ndfmc_priv *txx9_priv = nand_get_controller_data(chip);
135 	struct platform_device *dev = txx9_priv->dev;
136 	struct txx9ndfmc_platform_data *plat = dev_get_platdata(&dev->dev);
137 
138 	if (ctrl & NAND_CTRL_CHANGE) {
139 		u32 mcr = txx9ndfmc_read(dev, TXX9_NDFMCR);
140 
141 		mcr &= ~(TXX9_NDFMCR_CLE | TXX9_NDFMCR_ALE | TXX9_NDFMCR_CE);
142 		mcr |= ctrl & NAND_CLE ? TXX9_NDFMCR_CLE : 0;
143 		mcr |= ctrl & NAND_ALE ? TXX9_NDFMCR_ALE : 0;
144 		/* TXX9_NDFMCR_CE bit is 0:high 1:low */
145 		mcr |= ctrl & NAND_NCE ? TXX9_NDFMCR_CE : 0;
146 		if (txx9_priv->cs >= 0 && (ctrl & NAND_NCE)) {
147 			mcr &= ~TXX9_NDFMCR_CS_MASK;
148 			mcr |= TXX9_NDFMCR_CS(txx9_priv->cs);
149 		}
150 		txx9ndfmc_write(dev, mcr, TXX9_NDFMCR);
151 	}
152 	if (cmd != NAND_CMD_NONE)
153 		txx9ndfmc_write(dev, cmd & 0xff, TXX9_NDFDTR);
154 	if (plat->flags & NDFMC_PLAT_FLAG_DUMMYWRITE) {
155 		/* dummy write to update external latch */
156 		if ((ctrl & NAND_CTRL_CHANGE) && cmd == NAND_CMD_NONE)
157 			txx9ndfmc_write(dev, 0, TXX9_NDFDTR);
158 	}
159 }
160 
161 static int txx9ndfmc_dev_ready(struct nand_chip *chip)
162 {
163 	struct platform_device *dev = mtd_to_platdev(nand_to_mtd(chip));
164 
165 	return !(txx9ndfmc_read(dev, TXX9_NDFSR) & TXX9_NDFSR_BUSY);
166 }
167 
168 static int txx9ndfmc_calculate_ecc(struct nand_chip *chip, const uint8_t *dat,
169 				   uint8_t *ecc_code)
170 {
171 	struct platform_device *dev = mtd_to_platdev(nand_to_mtd(chip));
172 	int eccbytes;
173 	u32 mcr = txx9ndfmc_read(dev, TXX9_NDFMCR);
174 
175 	mcr &= ~TXX9_NDFMCR_ECC_ALL;
176 	txx9ndfmc_write(dev, mcr | TXX9_NDFMCR_ECC_OFF, TXX9_NDFMCR);
177 	txx9ndfmc_write(dev, mcr | TXX9_NDFMCR_ECC_READ, TXX9_NDFMCR);
178 	for (eccbytes = chip->ecc.bytes; eccbytes > 0; eccbytes -= 3) {
179 		ecc_code[1] = txx9ndfmc_read(dev, TXX9_NDFDTR);
180 		ecc_code[0] = txx9ndfmc_read(dev, TXX9_NDFDTR);
181 		ecc_code[2] = txx9ndfmc_read(dev, TXX9_NDFDTR);
182 		ecc_code += 3;
183 	}
184 	txx9ndfmc_write(dev, mcr | TXX9_NDFMCR_ECC_OFF, TXX9_NDFMCR);
185 	return 0;
186 }
187 
188 static int txx9ndfmc_correct_data(struct nand_chip *chip, unsigned char *buf,
189 				  unsigned char *read_ecc,
190 				  unsigned char *calc_ecc)
191 {
192 	int eccsize;
193 	int corrected = 0;
194 	int stat;
195 
196 	for (eccsize = chip->ecc.size; eccsize > 0; eccsize -= 256) {
197 		stat = __nand_correct_data(buf, read_ecc, calc_ecc, 256,
198 					   false);
199 		if (stat < 0)
200 			return stat;
201 		corrected += stat;
202 		buf += 256;
203 		read_ecc += 3;
204 		calc_ecc += 3;
205 	}
206 	return corrected;
207 }
208 
209 static void txx9ndfmc_enable_hwecc(struct nand_chip *chip, int mode)
210 {
211 	struct platform_device *dev = mtd_to_platdev(nand_to_mtd(chip));
212 	u32 mcr = txx9ndfmc_read(dev, TXX9_NDFMCR);
213 
214 	mcr &= ~TXX9_NDFMCR_ECC_ALL;
215 	txx9ndfmc_write(dev, mcr | TXX9_NDFMCR_ECC_RESET, TXX9_NDFMCR);
216 	txx9ndfmc_write(dev, mcr | TXX9_NDFMCR_ECC_OFF, TXX9_NDFMCR);
217 	txx9ndfmc_write(dev, mcr | TXX9_NDFMCR_ECC_ON, TXX9_NDFMCR);
218 }
219 
220 static void txx9ndfmc_initialize(struct platform_device *dev)
221 {
222 	struct txx9ndfmc_platform_data *plat = dev_get_platdata(&dev->dev);
223 	struct txx9ndfmc_drvdata *drvdata = platform_get_drvdata(dev);
224 	int tmout = 100;
225 
226 	if (plat->flags & NDFMC_PLAT_FLAG_NO_RSTR)
227 		; /* no NDFRSTR.  Write to NDFSPR resets the NDFMC. */
228 	else {
229 		/* reset NDFMC */
230 		txx9ndfmc_write(dev,
231 				txx9ndfmc_read(dev, TXX9_NDFRSTR) |
232 				TXX9_NDFRSTR_RST,
233 				TXX9_NDFRSTR);
234 		while (txx9ndfmc_read(dev, TXX9_NDFRSTR) & TXX9_NDFRSTR_RST) {
235 			if (--tmout == 0) {
236 				dev_err(&dev->dev, "reset failed.\n");
237 				break;
238 			}
239 			udelay(1);
240 		}
241 	}
242 	/* setup Hold Time, Strobe Pulse Width */
243 	txx9ndfmc_write(dev, (drvdata->hold << 4) | drvdata->spw, TXX9_NDFSPR);
244 	txx9ndfmc_write(dev,
245 			(plat->flags & NDFMC_PLAT_FLAG_USE_BSPRT) ?
246 			TXX9_NDFMCR_BSPRT : 0, TXX9_NDFMCR);
247 }
248 
249 #define TXX9NDFMC_NS_TO_CYC(gbusclk, ns) \
250 	DIV_ROUND_UP((ns) * DIV_ROUND_UP(gbusclk, 1000), 1000000)
251 
252 static int txx9ndfmc_attach_chip(struct nand_chip *chip)
253 {
254 	struct mtd_info *mtd = nand_to_mtd(chip);
255 
256 	if (mtd->writesize >= 512) {
257 		chip->ecc.size = 512;
258 		chip->ecc.bytes = 6;
259 	} else {
260 		chip->ecc.size = 256;
261 		chip->ecc.bytes = 3;
262 	}
263 
264 	return 0;
265 }
266 
267 static const struct nand_controller_ops txx9ndfmc_controller_ops = {
268 	.attach_chip = txx9ndfmc_attach_chip,
269 };
270 
271 static int __init txx9ndfmc_probe(struct platform_device *dev)
272 {
273 	struct txx9ndfmc_platform_data *plat = dev_get_platdata(&dev->dev);
274 	int hold, spw;
275 	int i;
276 	struct txx9ndfmc_drvdata *drvdata;
277 	unsigned long gbusclk = plat->gbus_clock;
278 	struct resource *res;
279 
280 	drvdata = devm_kzalloc(&dev->dev, sizeof(*drvdata), GFP_KERNEL);
281 	if (!drvdata)
282 		return -ENOMEM;
283 	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
284 	drvdata->base = devm_ioremap_resource(&dev->dev, res);
285 	if (IS_ERR(drvdata->base))
286 		return PTR_ERR(drvdata->base);
287 
288 	hold = plat->hold ?: 20; /* tDH */
289 	spw = plat->spw ?: 90; /* max(tREADID, tWP, tRP) */
290 
291 	hold = TXX9NDFMC_NS_TO_CYC(gbusclk, hold);
292 	spw = TXX9NDFMC_NS_TO_CYC(gbusclk, spw);
293 	if (plat->flags & NDFMC_PLAT_FLAG_HOLDADD)
294 		hold -= 2;	/* actual hold time : (HOLD + 2) BUSCLK */
295 	spw -= 1;	/* actual wait time : (SPW + 1) BUSCLK */
296 	hold = clamp(hold, 1, 15);
297 	drvdata->hold = hold;
298 	spw = clamp(spw, 1, 15);
299 	drvdata->spw = spw;
300 	dev_info(&dev->dev, "CLK:%ldMHz HOLD:%d SPW:%d\n",
301 		 (gbusclk + 500000) / 1000000, hold, spw);
302 
303 	nand_controller_init(&drvdata->controller);
304 	drvdata->controller.ops = &txx9ndfmc_controller_ops;
305 
306 	platform_set_drvdata(dev, drvdata);
307 	txx9ndfmc_initialize(dev);
308 
309 	for (i = 0; i < MAX_TXX9NDFMC_DEV; i++) {
310 		struct txx9ndfmc_priv *txx9_priv;
311 		struct nand_chip *chip;
312 		struct mtd_info *mtd;
313 
314 		if (!(plat->ch_mask & (1 << i)))
315 			continue;
316 		txx9_priv = kzalloc(sizeof(struct txx9ndfmc_priv),
317 				    GFP_KERNEL);
318 		if (!txx9_priv)
319 			continue;
320 		chip = &txx9_priv->chip;
321 		mtd = nand_to_mtd(chip);
322 		mtd->dev.parent = &dev->dev;
323 
324 		chip->legacy.read_byte = txx9ndfmc_read_byte;
325 		chip->legacy.read_buf = txx9ndfmc_read_buf;
326 		chip->legacy.write_buf = txx9ndfmc_write_buf;
327 		chip->legacy.cmd_ctrl = txx9ndfmc_cmd_ctrl;
328 		chip->legacy.dev_ready = txx9ndfmc_dev_ready;
329 		chip->ecc.calculate = txx9ndfmc_calculate_ecc;
330 		chip->ecc.correct = txx9ndfmc_correct_data;
331 		chip->ecc.hwctl = txx9ndfmc_enable_hwecc;
332 		chip->ecc.mode = NAND_ECC_HW;
333 		chip->ecc.strength = 1;
334 		chip->legacy.chip_delay = 100;
335 		chip->controller = &drvdata->controller;
336 
337 		nand_set_controller_data(chip, txx9_priv);
338 		txx9_priv->dev = dev;
339 
340 		if (plat->ch_mask != 1) {
341 			txx9_priv->cs = i;
342 			txx9_priv->mtdname = kasprintf(GFP_KERNEL, "%s.%u",
343 						       dev_name(&dev->dev), i);
344 		} else {
345 			txx9_priv->cs = -1;
346 			txx9_priv->mtdname = kstrdup(dev_name(&dev->dev),
347 						     GFP_KERNEL);
348 		}
349 		if (!txx9_priv->mtdname) {
350 			kfree(txx9_priv);
351 			dev_err(&dev->dev, "Unable to allocate MTD name.\n");
352 			continue;
353 		}
354 		if (plat->wide_mask & (1 << i))
355 			chip->options |= NAND_BUSWIDTH_16;
356 
357 		if (nand_scan(chip, 1)) {
358 			kfree(txx9_priv->mtdname);
359 			kfree(txx9_priv);
360 			continue;
361 		}
362 		mtd->name = txx9_priv->mtdname;
363 
364 		mtd_device_register(mtd, NULL, 0);
365 		drvdata->mtds[i] = mtd;
366 	}
367 
368 	return 0;
369 }
370 
371 static int __exit txx9ndfmc_remove(struct platform_device *dev)
372 {
373 	struct txx9ndfmc_drvdata *drvdata = platform_get_drvdata(dev);
374 	int ret, i;
375 
376 	if (!drvdata)
377 		return 0;
378 	for (i = 0; i < MAX_TXX9NDFMC_DEV; i++) {
379 		struct mtd_info *mtd = drvdata->mtds[i];
380 		struct nand_chip *chip;
381 		struct txx9ndfmc_priv *txx9_priv;
382 
383 		if (!mtd)
384 			continue;
385 		chip = mtd_to_nand(mtd);
386 		txx9_priv = nand_get_controller_data(chip);
387 
388 		ret = mtd_device_unregister(nand_to_mtd(chip));
389 		WARN_ON(ret);
390 		nand_cleanup(chip);
391 		kfree(txx9_priv->mtdname);
392 		kfree(txx9_priv);
393 	}
394 	return 0;
395 }
396 
397 #ifdef CONFIG_PM
398 static int txx9ndfmc_resume(struct platform_device *dev)
399 {
400 	if (platform_get_drvdata(dev))
401 		txx9ndfmc_initialize(dev);
402 	return 0;
403 }
404 #else
405 #define txx9ndfmc_resume NULL
406 #endif
407 
408 static struct platform_driver txx9ndfmc_driver = {
409 	.remove		= __exit_p(txx9ndfmc_remove),
410 	.resume		= txx9ndfmc_resume,
411 	.driver		= {
412 		.name	= "txx9ndfmc",
413 	},
414 };
415 
416 module_platform_driver_probe(txx9ndfmc_driver, txx9ndfmc_probe);
417 
418 MODULE_LICENSE("GPL");
419 MODULE_DESCRIPTION("TXx9 SoC NAND flash controller driver");
420 MODULE_ALIAS("platform:txx9ndfmc");
421