1 /*
2 * Copyright (C) 2009-2010, Lars-Peter Clausen <lars@metafoo.de>
3 * JZ4740 SoC NAND controller driver
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License as published by the
7 * Free Software Foundation; either version 2 of the License, or (at your
8 * option) any later version.
9 *
10 * You should have received a copy of the GNU General Public License along
11 * with this program; if not, write to the Free Software Foundation, Inc.,
12 * 675 Mass Ave, Cambridge, MA 02139, USA.
13 *
14 */
15
16 #include <linux/ioport.h>
17 #include <linux/kernel.h>
18 #include <linux/module.h>
19 #include <linux/platform_device.h>
20 #include <linux/slab.h>
21
22 #include <linux/mtd/mtd.h>
23 #include <linux/mtd/nand.h>
24 #include <linux/mtd/partitions.h>
25
26 #include <linux/gpio.h>
27
28 #include <asm/mach-jz4740/jz4740_nand.h>
29
30 #define JZ_REG_NAND_CTRL 0x50
31 #define JZ_REG_NAND_ECC_CTRL 0x100
32 #define JZ_REG_NAND_DATA 0x104
33 #define JZ_REG_NAND_PAR0 0x108
34 #define JZ_REG_NAND_PAR1 0x10C
35 #define JZ_REG_NAND_PAR2 0x110
36 #define JZ_REG_NAND_IRQ_STAT 0x114
37 #define JZ_REG_NAND_IRQ_CTRL 0x118
38 #define JZ_REG_NAND_ERR(x) (0x11C + ((x) << 2))
39
40 #define JZ_NAND_ECC_CTRL_PAR_READY BIT(4)
41 #define JZ_NAND_ECC_CTRL_ENCODING BIT(3)
42 #define JZ_NAND_ECC_CTRL_RS BIT(2)
43 #define JZ_NAND_ECC_CTRL_RESET BIT(1)
44 #define JZ_NAND_ECC_CTRL_ENABLE BIT(0)
45
46 #define JZ_NAND_STATUS_ERR_COUNT (BIT(31) | BIT(30) | BIT(29))
47 #define JZ_NAND_STATUS_PAD_FINISH BIT(4)
48 #define JZ_NAND_STATUS_DEC_FINISH BIT(3)
49 #define JZ_NAND_STATUS_ENC_FINISH BIT(2)
50 #define JZ_NAND_STATUS_UNCOR_ERROR BIT(1)
51 #define JZ_NAND_STATUS_ERROR BIT(0)
52
53 #define JZ_NAND_CTRL_ENABLE_CHIP(x) BIT((x) << 1)
54 #define JZ_NAND_CTRL_ASSERT_CHIP(x) BIT(((x) << 1) + 1)
55
56 #define JZ_NAND_MEM_ADDR_OFFSET 0x10000
57 #define JZ_NAND_MEM_CMD_OFFSET 0x08000
58
59 struct jz_nand {
60 struct mtd_info mtd;
61 struct nand_chip chip;
62 void __iomem *base;
63 struct resource *mem;
64
65 void __iomem *bank_base;
66 struct resource *bank_mem;
67
68 struct jz_nand_platform_data *pdata;
69 bool is_reading;
70 };
71
mtd_to_jz_nand(struct mtd_info * mtd)72 static inline struct jz_nand *mtd_to_jz_nand(struct mtd_info *mtd)
73 {
74 return container_of(mtd, struct jz_nand, mtd);
75 }
76
jz_nand_cmd_ctrl(struct mtd_info * mtd,int dat,unsigned int ctrl)77 static void jz_nand_cmd_ctrl(struct mtd_info *mtd, int dat, unsigned int ctrl)
78 {
79 struct jz_nand *nand = mtd_to_jz_nand(mtd);
80 struct nand_chip *chip = mtd->priv;
81 uint32_t reg;
82
83 if (ctrl & NAND_CTRL_CHANGE) {
84 BUG_ON((ctrl & NAND_ALE) && (ctrl & NAND_CLE));
85 if (ctrl & NAND_ALE)
86 chip->IO_ADDR_W = nand->bank_base + JZ_NAND_MEM_ADDR_OFFSET;
87 else if (ctrl & NAND_CLE)
88 chip->IO_ADDR_W = nand->bank_base + JZ_NAND_MEM_CMD_OFFSET;
89 else
90 chip->IO_ADDR_W = nand->bank_base;
91
92 reg = readl(nand->base + JZ_REG_NAND_CTRL);
93 if (ctrl & NAND_NCE)
94 reg |= JZ_NAND_CTRL_ASSERT_CHIP(0);
95 else
96 reg &= ~JZ_NAND_CTRL_ASSERT_CHIP(0);
97 writel(reg, nand->base + JZ_REG_NAND_CTRL);
98 }
99 if (dat != NAND_CMD_NONE)
100 writeb(dat, chip->IO_ADDR_W);
101 }
102
jz_nand_dev_ready(struct mtd_info * mtd)103 static int jz_nand_dev_ready(struct mtd_info *mtd)
104 {
105 struct jz_nand *nand = mtd_to_jz_nand(mtd);
106 return gpio_get_value_cansleep(nand->pdata->busy_gpio);
107 }
108
jz_nand_hwctl(struct mtd_info * mtd,int mode)109 static void jz_nand_hwctl(struct mtd_info *mtd, int mode)
110 {
111 struct jz_nand *nand = mtd_to_jz_nand(mtd);
112 uint32_t reg;
113
114 writel(0, nand->base + JZ_REG_NAND_IRQ_STAT);
115 reg = readl(nand->base + JZ_REG_NAND_ECC_CTRL);
116
117 reg |= JZ_NAND_ECC_CTRL_RESET;
118 reg |= JZ_NAND_ECC_CTRL_ENABLE;
119 reg |= JZ_NAND_ECC_CTRL_RS;
120
121 switch (mode) {
122 case NAND_ECC_READ:
123 reg &= ~JZ_NAND_ECC_CTRL_ENCODING;
124 nand->is_reading = true;
125 break;
126 case NAND_ECC_WRITE:
127 reg |= JZ_NAND_ECC_CTRL_ENCODING;
128 nand->is_reading = false;
129 break;
130 default:
131 break;
132 }
133
134 writel(reg, nand->base + JZ_REG_NAND_ECC_CTRL);
135 }
136
jz_nand_calculate_ecc_rs(struct mtd_info * mtd,const uint8_t * dat,uint8_t * ecc_code)137 static int jz_nand_calculate_ecc_rs(struct mtd_info *mtd, const uint8_t *dat,
138 uint8_t *ecc_code)
139 {
140 struct jz_nand *nand = mtd_to_jz_nand(mtd);
141 uint32_t reg, status;
142 int i;
143 unsigned int timeout = 1000;
144 static uint8_t empty_block_ecc[] = {0xcd, 0x9d, 0x90, 0x58, 0xf4,
145 0x8b, 0xff, 0xb7, 0x6f};
146
147 if (nand->is_reading)
148 return 0;
149
150 do {
151 status = readl(nand->base + JZ_REG_NAND_IRQ_STAT);
152 } while (!(status & JZ_NAND_STATUS_ENC_FINISH) && --timeout);
153
154 if (timeout == 0)
155 return -1;
156
157 reg = readl(nand->base + JZ_REG_NAND_ECC_CTRL);
158 reg &= ~JZ_NAND_ECC_CTRL_ENABLE;
159 writel(reg, nand->base + JZ_REG_NAND_ECC_CTRL);
160
161 for (i = 0; i < 9; ++i)
162 ecc_code[i] = readb(nand->base + JZ_REG_NAND_PAR0 + i);
163
164 /* If the written data is completly 0xff, we also want to write 0xff as
165 * ecc, otherwise we will get in trouble when doing subpage writes. */
166 if (memcmp(ecc_code, empty_block_ecc, 9) == 0)
167 memset(ecc_code, 0xff, 9);
168
169 return 0;
170 }
171
jz_nand_correct_data(uint8_t * dat,int index,int mask)172 static void jz_nand_correct_data(uint8_t *dat, int index, int mask)
173 {
174 int offset = index & 0x7;
175 uint16_t data;
176
177 index += (index >> 3);
178
179 data = dat[index];
180 data |= dat[index+1] << 8;
181
182 mask ^= (data >> offset) & 0x1ff;
183 data &= ~(0x1ff << offset);
184 data |= (mask << offset);
185
186 dat[index] = data & 0xff;
187 dat[index+1] = (data >> 8) & 0xff;
188 }
189
jz_nand_correct_ecc_rs(struct mtd_info * mtd,uint8_t * dat,uint8_t * read_ecc,uint8_t * calc_ecc)190 static int jz_nand_correct_ecc_rs(struct mtd_info *mtd, uint8_t *dat,
191 uint8_t *read_ecc, uint8_t *calc_ecc)
192 {
193 struct jz_nand *nand = mtd_to_jz_nand(mtd);
194 int i, error_count, index;
195 uint32_t reg, status, error;
196 uint32_t t;
197 unsigned int timeout = 1000;
198
199 t = read_ecc[0];
200
201 if (t == 0xff) {
202 for (i = 1; i < 9; ++i)
203 t &= read_ecc[i];
204
205 t &= dat[0];
206 t &= dat[nand->chip.ecc.size / 2];
207 t &= dat[nand->chip.ecc.size - 1];
208
209 if (t == 0xff) {
210 for (i = 1; i < nand->chip.ecc.size - 1; ++i)
211 t &= dat[i];
212 if (t == 0xff)
213 return 0;
214 }
215 }
216
217 for (i = 0; i < 9; ++i)
218 writeb(read_ecc[i], nand->base + JZ_REG_NAND_PAR0 + i);
219
220 reg = readl(nand->base + JZ_REG_NAND_ECC_CTRL);
221 reg |= JZ_NAND_ECC_CTRL_PAR_READY;
222 writel(reg, nand->base + JZ_REG_NAND_ECC_CTRL);
223
224 do {
225 status = readl(nand->base + JZ_REG_NAND_IRQ_STAT);
226 } while (!(status & JZ_NAND_STATUS_DEC_FINISH) && --timeout);
227
228 if (timeout == 0)
229 return -1;
230
231 reg = readl(nand->base + JZ_REG_NAND_ECC_CTRL);
232 reg &= ~JZ_NAND_ECC_CTRL_ENABLE;
233 writel(reg, nand->base + JZ_REG_NAND_ECC_CTRL);
234
235 if (status & JZ_NAND_STATUS_ERROR) {
236 if (status & JZ_NAND_STATUS_UNCOR_ERROR)
237 return -1;
238
239 error_count = (status & JZ_NAND_STATUS_ERR_COUNT) >> 29;
240
241 for (i = 0; i < error_count; ++i) {
242 error = readl(nand->base + JZ_REG_NAND_ERR(i));
243 index = ((error >> 16) & 0x1ff) - 1;
244 if (index >= 0 && index < 512)
245 jz_nand_correct_data(dat, index, error & 0x1ff);
246 }
247
248 return error_count;
249 }
250
251 return 0;
252 }
253
jz_nand_ioremap_resource(struct platform_device * pdev,const char * name,struct resource ** res,void __iomem ** base)254 static int jz_nand_ioremap_resource(struct platform_device *pdev,
255 const char *name, struct resource **res, void __iomem **base)
256 {
257 int ret;
258
259 *res = platform_get_resource_byname(pdev, IORESOURCE_MEM, name);
260 if (!*res) {
261 dev_err(&pdev->dev, "Failed to get platform %s memory\n", name);
262 ret = -ENXIO;
263 goto err;
264 }
265
266 *res = request_mem_region((*res)->start, resource_size(*res),
267 pdev->name);
268 if (!*res) {
269 dev_err(&pdev->dev, "Failed to request %s memory region\n", name);
270 ret = -EBUSY;
271 goto err;
272 }
273
274 *base = ioremap((*res)->start, resource_size(*res));
275 if (!*base) {
276 dev_err(&pdev->dev, "Failed to ioremap %s memory region\n", name);
277 ret = -EBUSY;
278 goto err_release_mem;
279 }
280
281 return 0;
282
283 err_release_mem:
284 release_mem_region((*res)->start, resource_size(*res));
285 err:
286 *res = NULL;
287 *base = NULL;
288 return ret;
289 }
290
jz_nand_probe(struct platform_device * pdev)291 static int __devinit jz_nand_probe(struct platform_device *pdev)
292 {
293 int ret;
294 struct jz_nand *nand;
295 struct nand_chip *chip;
296 struct mtd_info *mtd;
297 struct jz_nand_platform_data *pdata = pdev->dev.platform_data;
298
299 nand = kzalloc(sizeof(*nand), GFP_KERNEL);
300 if (!nand) {
301 dev_err(&pdev->dev, "Failed to allocate device structure.\n");
302 return -ENOMEM;
303 }
304
305 ret = jz_nand_ioremap_resource(pdev, "mmio", &nand->mem, &nand->base);
306 if (ret)
307 goto err_free;
308 ret = jz_nand_ioremap_resource(pdev, "bank", &nand->bank_mem,
309 &nand->bank_base);
310 if (ret)
311 goto err_iounmap_mmio;
312
313 if (pdata && gpio_is_valid(pdata->busy_gpio)) {
314 ret = gpio_request(pdata->busy_gpio, "NAND busy pin");
315 if (ret) {
316 dev_err(&pdev->dev,
317 "Failed to request busy gpio %d: %d\n",
318 pdata->busy_gpio, ret);
319 goto err_iounmap_mem;
320 }
321 }
322
323 mtd = &nand->mtd;
324 chip = &nand->chip;
325 mtd->priv = chip;
326 mtd->owner = THIS_MODULE;
327 mtd->name = "jz4740-nand";
328
329 chip->ecc.hwctl = jz_nand_hwctl;
330 chip->ecc.calculate = jz_nand_calculate_ecc_rs;
331 chip->ecc.correct = jz_nand_correct_ecc_rs;
332 chip->ecc.mode = NAND_ECC_HW_OOB_FIRST;
333 chip->ecc.size = 512;
334 chip->ecc.bytes = 9;
335 chip->ecc.strength = 2;
336 /*
337 * FIXME: ecc_strength value of 2 bits per 512 bytes of data is a
338 * conservative guess, given 9 ecc bytes and reed-solomon alg.
339 */
340
341 if (pdata)
342 chip->ecc.layout = pdata->ecc_layout;
343
344 chip->chip_delay = 50;
345 chip->cmd_ctrl = jz_nand_cmd_ctrl;
346
347 if (pdata && gpio_is_valid(pdata->busy_gpio))
348 chip->dev_ready = jz_nand_dev_ready;
349
350 chip->IO_ADDR_R = nand->bank_base;
351 chip->IO_ADDR_W = nand->bank_base;
352
353 nand->pdata = pdata;
354 platform_set_drvdata(pdev, nand);
355
356 writel(JZ_NAND_CTRL_ENABLE_CHIP(0), nand->base + JZ_REG_NAND_CTRL);
357
358 ret = nand_scan_ident(mtd, 1, NULL);
359 if (ret) {
360 dev_err(&pdev->dev, "Failed to scan nand\n");
361 goto err_gpio_free;
362 }
363
364 if (pdata && pdata->ident_callback) {
365 pdata->ident_callback(pdev, chip, &pdata->partitions,
366 &pdata->num_partitions);
367 }
368
369 ret = nand_scan_tail(mtd);
370 if (ret) {
371 dev_err(&pdev->dev, "Failed to scan nand\n");
372 goto err_gpio_free;
373 }
374
375 ret = mtd_device_parse_register(mtd, NULL, NULL,
376 pdata ? pdata->partitions : NULL,
377 pdata ? pdata->num_partitions : 0);
378
379 if (ret) {
380 dev_err(&pdev->dev, "Failed to add mtd device\n");
381 goto err_nand_release;
382 }
383
384 dev_info(&pdev->dev, "Successfully registered JZ4740 NAND driver\n");
385
386 return 0;
387
388 err_nand_release:
389 nand_release(&nand->mtd);
390 err_gpio_free:
391 platform_set_drvdata(pdev, NULL);
392 gpio_free(pdata->busy_gpio);
393 err_iounmap_mem:
394 iounmap(nand->bank_base);
395 err_iounmap_mmio:
396 iounmap(nand->base);
397 err_free:
398 kfree(nand);
399 return ret;
400 }
401
jz_nand_remove(struct platform_device * pdev)402 static int __devexit jz_nand_remove(struct platform_device *pdev)
403 {
404 struct jz_nand *nand = platform_get_drvdata(pdev);
405
406 nand_release(&nand->mtd);
407
408 /* Deassert and disable all chips */
409 writel(0, nand->base + JZ_REG_NAND_CTRL);
410
411 iounmap(nand->bank_base);
412 release_mem_region(nand->bank_mem->start, resource_size(nand->bank_mem));
413 iounmap(nand->base);
414 release_mem_region(nand->mem->start, resource_size(nand->mem));
415
416 platform_set_drvdata(pdev, NULL);
417 kfree(nand);
418
419 return 0;
420 }
421
422 static struct platform_driver jz_nand_driver = {
423 .probe = jz_nand_probe,
424 .remove = __devexit_p(jz_nand_remove),
425 .driver = {
426 .name = "jz4740-nand",
427 .owner = THIS_MODULE,
428 },
429 };
430
431 module_platform_driver(jz_nand_driver);
432
433 MODULE_LICENSE("GPL");
434 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
435 MODULE_DESCRIPTION("NAND controller driver for JZ4740 SoC");
436 MODULE_ALIAS("platform:jz4740-nand");
437