Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wirel...
[pandora-kernel.git] / drivers / mtd / nand / jz4740_nand.c
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
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
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
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
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
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
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
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
254 #ifdef CONFIG_MTD_CMDLINE_PARTS
255 static const char *part_probes[] = {"cmdline", NULL};
256 #endif
257
258 static int jz_nand_ioremap_resource(struct platform_device *pdev,
259         const char *name, struct resource **res, void __iomem **base)
260 {
261         int ret;
262
263         *res = platform_get_resource_byname(pdev, IORESOURCE_MEM, name);
264         if (!*res) {
265                 dev_err(&pdev->dev, "Failed to get platform %s memory\n", name);
266                 ret = -ENXIO;
267                 goto err;
268         }
269
270         *res = request_mem_region((*res)->start, resource_size(*res),
271                                 pdev->name);
272         if (!*res) {
273                 dev_err(&pdev->dev, "Failed to request %s memory region\n", name);
274                 ret = -EBUSY;
275                 goto err;
276         }
277
278         *base = ioremap((*res)->start, resource_size(*res));
279         if (!*base) {
280                 dev_err(&pdev->dev, "Failed to ioremap %s memory region\n", name);
281                 ret = -EBUSY;
282                 goto err_release_mem;
283         }
284
285         return 0;
286
287 err_release_mem:
288         release_mem_region((*res)->start, resource_size(*res));
289 err:
290         *res = NULL;
291         *base = NULL;
292         return ret;
293 }
294
295 static int __devinit jz_nand_probe(struct platform_device *pdev)
296 {
297         int ret;
298         struct jz_nand *nand;
299         struct nand_chip *chip;
300         struct mtd_info *mtd;
301         struct jz_nand_platform_data *pdata = pdev->dev.platform_data;
302         struct mtd_partition *partition_info;
303         int num_partitions = 0;
304
305         nand = kzalloc(sizeof(*nand), GFP_KERNEL);
306         if (!nand) {
307                 dev_err(&pdev->dev, "Failed to allocate device structure.\n");
308                 return -ENOMEM;
309         }
310
311         ret = jz_nand_ioremap_resource(pdev, "mmio", &nand->mem, &nand->base);
312         if (ret)
313                 goto err_free;
314         ret = jz_nand_ioremap_resource(pdev, "bank", &nand->bank_mem,
315                         &nand->bank_base);
316         if (ret)
317                 goto err_iounmap_mmio;
318
319         if (pdata && gpio_is_valid(pdata->busy_gpio)) {
320                 ret = gpio_request(pdata->busy_gpio, "NAND busy pin");
321                 if (ret) {
322                         dev_err(&pdev->dev,
323                                 "Failed to request busy gpio %d: %d\n",
324                                 pdata->busy_gpio, ret);
325                         goto err_iounmap_mem;
326                 }
327         }
328
329         mtd             = &nand->mtd;
330         chip            = &nand->chip;
331         mtd->priv       = chip;
332         mtd->owner      = THIS_MODULE;
333         mtd->name       = "jz4740-nand";
334
335         chip->ecc.hwctl         = jz_nand_hwctl;
336         chip->ecc.calculate     = jz_nand_calculate_ecc_rs;
337         chip->ecc.correct       = jz_nand_correct_ecc_rs;
338         chip->ecc.mode          = NAND_ECC_HW_OOB_FIRST;
339         chip->ecc.size          = 512;
340         chip->ecc.bytes         = 9;
341
342         if (pdata)
343                 chip->ecc.layout = pdata->ecc_layout;
344
345         chip->chip_delay = 50;
346         chip->cmd_ctrl = jz_nand_cmd_ctrl;
347
348         if (pdata && gpio_is_valid(pdata->busy_gpio))
349                 chip->dev_ready = jz_nand_dev_ready;
350
351         chip->IO_ADDR_R = nand->bank_base;
352         chip->IO_ADDR_W = nand->bank_base;
353
354         nand->pdata = pdata;
355         platform_set_drvdata(pdev, nand);
356
357         writel(JZ_NAND_CTRL_ENABLE_CHIP(0), nand->base + JZ_REG_NAND_CTRL);
358
359         ret = nand_scan_ident(mtd, 1, NULL);
360         if (ret) {
361                 dev_err(&pdev->dev,  "Failed to scan nand\n");
362                 goto err_gpio_free;
363         }
364
365         if (pdata && pdata->ident_callback) {
366                 pdata->ident_callback(pdev, chip, &pdata->partitions,
367                                         &pdata->num_partitions);
368         }
369
370         ret = nand_scan_tail(mtd);
371         if (ret) {
372                 dev_err(&pdev->dev,  "Failed to scan nand\n");
373                 goto err_gpio_free;
374         }
375
376 #ifdef CONFIG_MTD_CMDLINE_PARTS
377         num_partitions = parse_mtd_partitions(mtd, part_probes,
378                                                 &partition_info, 0);
379 #endif
380         if (num_partitions <= 0 && pdata) {
381                 num_partitions = pdata->num_partitions;
382                 partition_info = pdata->partitions;
383         }
384         ret = mtd_device_register(mtd, partition_info, num_partitions);
385
386         if (ret) {
387                 dev_err(&pdev->dev, "Failed to add mtd device\n");
388                 goto err_nand_release;
389         }
390
391         dev_info(&pdev->dev, "Successfully registered JZ4740 NAND driver\n");
392
393         return 0;
394
395 err_nand_release:
396         nand_release(&nand->mtd);
397 err_gpio_free:
398         platform_set_drvdata(pdev, NULL);
399         gpio_free(pdata->busy_gpio);
400 err_iounmap_mem:
401         iounmap(nand->bank_base);
402 err_iounmap_mmio:
403         iounmap(nand->base);
404 err_free:
405         kfree(nand);
406         return ret;
407 }
408
409 static int __devexit jz_nand_remove(struct platform_device *pdev)
410 {
411         struct jz_nand *nand = platform_get_drvdata(pdev);
412
413         nand_release(&nand->mtd);
414
415         /* Deassert and disable all chips */
416         writel(0, nand->base + JZ_REG_NAND_CTRL);
417
418         iounmap(nand->bank_base);
419         release_mem_region(nand->bank_mem->start, resource_size(nand->bank_mem));
420         iounmap(nand->base);
421         release_mem_region(nand->mem->start, resource_size(nand->mem));
422
423         platform_set_drvdata(pdev, NULL);
424         kfree(nand);
425
426         return 0;
427 }
428
429 static struct platform_driver jz_nand_driver = {
430         .probe = jz_nand_probe,
431         .remove = __devexit_p(jz_nand_remove),
432         .driver = {
433                 .name = "jz4740-nand",
434                 .owner = THIS_MODULE,
435         },
436 };
437
438 static int __init jz_nand_init(void)
439 {
440         return platform_driver_register(&jz_nand_driver);
441 }
442 module_init(jz_nand_init);
443
444 static void __exit jz_nand_exit(void)
445 {
446         platform_driver_unregister(&jz_nand_driver);
447 }
448 module_exit(jz_nand_exit);
449
450 MODULE_LICENSE("GPL");
451 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
452 MODULE_DESCRIPTION("NAND controller driver for JZ4740 SoC");
453 MODULE_ALIAS("platform:jz4740-nand");