Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable
[linux-2.6] / drivers / mtd / nand / ndfc.c
1 /*
2  *  drivers/mtd/ndfc.c
3  *
4  *  Overview:
5  *   Platform independent driver for NDFC (NanD Flash Controller)
6  *   integrated into EP440 cores
7  *
8  *   Ported to an OF platform driver by Sean MacLennan
9  *
10  *   The NDFC supports multiple chips, but this driver only supports a
11  *   single chip since I do not have access to any boards with
12  *   multiple chips.
13  *
14  *  Author: Thomas Gleixner
15  *
16  *  Copyright 2006 IBM
17  *  Copyright 2008 PIKA Technologies
18  *    Sean MacLennan <smaclennan@pikatech.com>
19  *
20  *  This program is free software; you can redistribute  it and/or modify it
21  *  under  the terms of  the GNU General  Public License as published by the
22  *  Free Software Foundation;  either version 2 of the  License, or (at your
23  *  option) any later version.
24  *
25  */
26 #include <linux/module.h>
27 #include <linux/mtd/nand.h>
28 #include <linux/mtd/nand_ecc.h>
29 #include <linux/mtd/partitions.h>
30 #include <linux/mtd/ndfc.h>
31 #include <linux/mtd/mtd.h>
32 #include <linux/of_platform.h>
33 #include <asm/io.h>
34
35
36 struct ndfc_controller {
37         struct of_device *ofdev;
38         void __iomem *ndfcbase;
39         struct mtd_info mtd;
40         struct nand_chip chip;
41         int chip_select;
42         struct nand_hw_control ndfc_control;
43 #ifdef CONFIG_MTD_PARTITIONS
44         struct mtd_partition *parts;
45 #endif
46 };
47
48 static struct ndfc_controller ndfc_ctrl;
49
50 static void ndfc_select_chip(struct mtd_info *mtd, int chip)
51 {
52         uint32_t ccr;
53         struct ndfc_controller *ndfc = &ndfc_ctrl;
54
55         ccr = in_be32(ndfc->ndfcbase + NDFC_CCR);
56         if (chip >= 0) {
57                 ccr &= ~NDFC_CCR_BS_MASK;
58                 ccr |= NDFC_CCR_BS(chip + ndfc->chip_select);
59         } else
60                 ccr |= NDFC_CCR_RESET_CE;
61         out_be32(ndfc->ndfcbase + NDFC_CCR, ccr);
62 }
63
64 static void ndfc_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int ctrl)
65 {
66         struct ndfc_controller *ndfc = &ndfc_ctrl;
67
68         if (cmd == NAND_CMD_NONE)
69                 return;
70
71         if (ctrl & NAND_CLE)
72                 writel(cmd & 0xFF, ndfc->ndfcbase + NDFC_CMD);
73         else
74                 writel(cmd & 0xFF, ndfc->ndfcbase + NDFC_ALE);
75 }
76
77 static int ndfc_ready(struct mtd_info *mtd)
78 {
79         struct ndfc_controller *ndfc = &ndfc_ctrl;
80
81         return in_be32(ndfc->ndfcbase + NDFC_STAT) & NDFC_STAT_IS_READY;
82 }
83
84 static void ndfc_enable_hwecc(struct mtd_info *mtd, int mode)
85 {
86         uint32_t ccr;
87         struct ndfc_controller *ndfc = &ndfc_ctrl;
88
89         ccr = in_be32(ndfc->ndfcbase + NDFC_CCR);
90         ccr |= NDFC_CCR_RESET_ECC;
91         out_be32(ndfc->ndfcbase + NDFC_CCR, ccr);
92         wmb();
93 }
94
95 static int ndfc_calculate_ecc(struct mtd_info *mtd,
96                               const u_char *dat, u_char *ecc_code)
97 {
98         struct ndfc_controller *ndfc = &ndfc_ctrl;
99         uint32_t ecc;
100         uint8_t *p = (uint8_t *)&ecc;
101
102         wmb();
103         ecc = in_be32(ndfc->ndfcbase + NDFC_ECC);
104         /* The NDFC uses Smart Media (SMC) bytes order */
105         ecc_code[0] = p[2];
106         ecc_code[1] = p[1];
107         ecc_code[2] = p[3];
108
109         return 0;
110 }
111
112 /*
113  * Speedups for buffer read/write/verify
114  *
115  * NDFC allows 32bit read/write of data. So we can speed up the buffer
116  * functions. No further checking, as nand_base will always read/write
117  * page aligned.
118  */
119 static void ndfc_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
120 {
121         struct ndfc_controller *ndfc = &ndfc_ctrl;
122         uint32_t *p = (uint32_t *) buf;
123
124         for(;len > 0; len -= 4)
125                 *p++ = in_be32(ndfc->ndfcbase + NDFC_DATA);
126 }
127
128 static void ndfc_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
129 {
130         struct ndfc_controller *ndfc = &ndfc_ctrl;
131         uint32_t *p = (uint32_t *) buf;
132
133         for(;len > 0; len -= 4)
134                 out_be32(ndfc->ndfcbase + NDFC_DATA, *p++);
135 }
136
137 static int ndfc_verify_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
138 {
139         struct ndfc_controller *ndfc = &ndfc_ctrl;
140         uint32_t *p = (uint32_t *) buf;
141
142         for(;len > 0; len -= 4)
143                 if (*p++ != in_be32(ndfc->ndfcbase + NDFC_DATA))
144                         return -EFAULT;
145         return 0;
146 }
147
148 /*
149  * Initialize chip structure
150  */
151 static int ndfc_chip_init(struct ndfc_controller *ndfc,
152                           struct device_node *node)
153 {
154 #ifdef CONFIG_MTD_PARTITIONS
155 #ifdef CONFIG_MTD_CMDLINE_PARTS
156         static const char *part_types[] = { "cmdlinepart", NULL };
157 #else
158         static const char *part_types[] = { NULL };
159 #endif
160 #endif
161         struct device_node *flash_np;
162         struct nand_chip *chip = &ndfc->chip;
163         int ret;
164
165         chip->IO_ADDR_R = ndfc->ndfcbase + NDFC_DATA;
166         chip->IO_ADDR_W = ndfc->ndfcbase + NDFC_DATA;
167         chip->cmd_ctrl = ndfc_hwcontrol;
168         chip->dev_ready = ndfc_ready;
169         chip->select_chip = ndfc_select_chip;
170         chip->chip_delay = 50;
171         chip->controller = &ndfc->ndfc_control;
172         chip->read_buf = ndfc_read_buf;
173         chip->write_buf = ndfc_write_buf;
174         chip->verify_buf = ndfc_verify_buf;
175         chip->ecc.correct = nand_correct_data;
176         chip->ecc.hwctl = ndfc_enable_hwecc;
177         chip->ecc.calculate = ndfc_calculate_ecc;
178         chip->ecc.mode = NAND_ECC_HW;
179         chip->ecc.size = 256;
180         chip->ecc.bytes = 3;
181
182         ndfc->mtd.priv = chip;
183         ndfc->mtd.owner = THIS_MODULE;
184
185         flash_np = of_get_next_child(node, NULL);
186         if (!flash_np)
187                 return -ENODEV;
188
189         ndfc->mtd.name = kasprintf(GFP_KERNEL, "%s.%s",
190                                    ndfc->ofdev->dev.bus_id, flash_np->name);
191         if (!ndfc->mtd.name) {
192                 ret = -ENOMEM;
193                 goto err;
194         }
195
196         ret = nand_scan(&ndfc->mtd, 1);
197         if (ret)
198                 goto err;
199
200 #ifdef CONFIG_MTD_PARTITIONS
201         ret = parse_mtd_partitions(&ndfc->mtd, part_types, &ndfc->parts, 0);
202         if (ret < 0)
203                 goto err;
204
205 #ifdef CONFIG_MTD_OF_PARTS
206         if (ret == 0) {
207                 ret = of_mtd_parse_partitions(&ndfc->ofdev->dev, flash_np,
208                                               &ndfc->parts);
209                 if (ret < 0)
210                         goto err;
211         }
212 #endif
213
214         if (ret > 0)
215                 ret = add_mtd_partitions(&ndfc->mtd, ndfc->parts, ret);
216         else
217 #endif
218                 ret = add_mtd_device(&ndfc->mtd);
219
220 err:
221         of_node_put(flash_np);
222         if (ret)
223                 kfree(ndfc->mtd.name);
224         return ret;
225 }
226
227 static int __devinit ndfc_probe(struct of_device *ofdev,
228                                 const struct of_device_id *match)
229 {
230         struct ndfc_controller *ndfc = &ndfc_ctrl;
231         const u32 *reg;
232         u32 ccr;
233         int err, len;
234
235         spin_lock_init(&ndfc->ndfc_control.lock);
236         init_waitqueue_head(&ndfc->ndfc_control.wq);
237         ndfc->ofdev = ofdev;
238         dev_set_drvdata(&ofdev->dev, ndfc);
239
240         /* Read the reg property to get the chip select */
241         reg = of_get_property(ofdev->node, "reg", &len);
242         if (reg == NULL || len != 12) {
243                 dev_err(&ofdev->dev, "unable read reg property (%d)\n", len);
244                 return -ENOENT;
245         }
246         ndfc->chip_select = reg[0];
247
248         ndfc->ndfcbase = of_iomap(ofdev->node, 0);
249         if (!ndfc->ndfcbase) {
250                 dev_err(&ofdev->dev, "failed to get memory\n");
251                 return -EIO;
252         }
253
254         ccr = NDFC_CCR_BS(ndfc->chip_select);
255
256         /* It is ok if ccr does not exist - just default to 0 */
257         reg = of_get_property(ofdev->node, "ccr", NULL);
258         if (reg)
259                 ccr |= *reg;
260
261         out_be32(ndfc->ndfcbase + NDFC_CCR, ccr);
262
263         /* Set the bank settings if given */
264         reg = of_get_property(ofdev->node, "bank-settings", NULL);
265         if (reg) {
266                 int offset = NDFC_BCFG0 + (ndfc->chip_select << 2);
267                 out_be32(ndfc->ndfcbase + offset, *reg);
268         }
269
270         err = ndfc_chip_init(ndfc, ofdev->node);
271         if (err) {
272                 iounmap(ndfc->ndfcbase);
273                 return err;
274         }
275
276         return 0;
277 }
278
279 static int __devexit ndfc_remove(struct of_device *ofdev)
280 {
281         struct ndfc_controller *ndfc = dev_get_drvdata(&ofdev->dev);
282
283         nand_release(&ndfc->mtd);
284
285         return 0;
286 }
287
288 static const struct of_device_id ndfc_match[] = {
289         { .compatible = "ibm,ndfc", },
290         {}
291 };
292 MODULE_DEVICE_TABLE(of, ndfc_match);
293
294 static struct of_platform_driver ndfc_driver = {
295         .driver = {
296                 .name   = "ndfc",
297         },
298         .match_table = ndfc_match,
299         .probe = ndfc_probe,
300         .remove = __devexit_p(ndfc_remove),
301 };
302
303 static int __init ndfc_nand_init(void)
304 {
305         return of_register_platform_driver(&ndfc_driver);
306 }
307
308 static void __exit ndfc_nand_exit(void)
309 {
310         of_unregister_platform_driver(&ndfc_driver);
311 }
312
313 module_init(ndfc_nand_init);
314 module_exit(ndfc_nand_exit);
315
316 MODULE_LICENSE("GPL");
317 MODULE_AUTHOR("Thomas Gleixner <tglx@linutronix.de>");
318 MODULE_DESCRIPTION("OF Platform driver for NDFC");