xref: /openbmc/linux/drivers/mtd/nand/raw/ndfc.c (revision c900529f3d9161bfde5cca0754f83b4d3c3e0220)
1  // SPDX-License-Identifier: GPL-2.0-or-later
2  /*
3   *  Overview:
4   *   Platform independent driver for NDFC (NanD Flash Controller)
5   *   integrated into EP440 cores
6   *
7   *   Ported to an OF platform driver by Sean MacLennan
8   *
9   *   The NDFC supports multiple chips, but this driver only supports a
10   *   single chip since I do not have access to any boards with
11   *   multiple chips.
12   *
13   *  Author: Thomas Gleixner
14   *
15   *  Copyright 2006 IBM
16   *  Copyright 2008 PIKA Technologies
17   *    Sean MacLennan <smaclennan@pikatech.com>
18   */
19  #include <linux/module.h>
20  #include <linux/mtd/rawnand.h>
21  #include <linux/mtd/partitions.h>
22  #include <linux/mtd/ndfc.h>
23  #include <linux/slab.h>
24  #include <linux/mtd/mtd.h>
25  #include <linux/of.h>
26  #include <linux/of_address.h>
27  #include <linux/platform_device.h>
28  #include <asm/io.h>
29  
30  #define NDFC_MAX_CS    4
31  
32  struct ndfc_controller {
33  	struct platform_device *ofdev;
34  	void __iomem *ndfcbase;
35  	struct nand_chip chip;
36  	int chip_select;
37  	struct nand_controller ndfc_control;
38  };
39  
40  static struct ndfc_controller ndfc_ctrl[NDFC_MAX_CS];
41  
ndfc_select_chip(struct nand_chip * nchip,int chip)42  static void ndfc_select_chip(struct nand_chip *nchip, int chip)
43  {
44  	uint32_t ccr;
45  	struct ndfc_controller *ndfc = nand_get_controller_data(nchip);
46  
47  	ccr = in_be32(ndfc->ndfcbase + NDFC_CCR);
48  	if (chip >= 0) {
49  		ccr &= ~NDFC_CCR_BS_MASK;
50  		ccr |= NDFC_CCR_BS(chip + ndfc->chip_select);
51  	} else
52  		ccr |= NDFC_CCR_RESET_CE;
53  	out_be32(ndfc->ndfcbase + NDFC_CCR, ccr);
54  }
55  
ndfc_hwcontrol(struct nand_chip * chip,int cmd,unsigned int ctrl)56  static void ndfc_hwcontrol(struct nand_chip *chip, int cmd, unsigned int ctrl)
57  {
58  	struct ndfc_controller *ndfc = nand_get_controller_data(chip);
59  
60  	if (cmd == NAND_CMD_NONE)
61  		return;
62  
63  	if (ctrl & NAND_CLE)
64  		writel(cmd & 0xFF, ndfc->ndfcbase + NDFC_CMD);
65  	else
66  		writel(cmd & 0xFF, ndfc->ndfcbase + NDFC_ALE);
67  }
68  
ndfc_ready(struct nand_chip * chip)69  static int ndfc_ready(struct nand_chip *chip)
70  {
71  	struct ndfc_controller *ndfc = nand_get_controller_data(chip);
72  
73  	return in_be32(ndfc->ndfcbase + NDFC_STAT) & NDFC_STAT_IS_READY;
74  }
75  
ndfc_enable_hwecc(struct nand_chip * chip,int mode)76  static void ndfc_enable_hwecc(struct nand_chip *chip, int mode)
77  {
78  	uint32_t ccr;
79  	struct ndfc_controller *ndfc = nand_get_controller_data(chip);
80  
81  	ccr = in_be32(ndfc->ndfcbase + NDFC_CCR);
82  	ccr |= NDFC_CCR_RESET_ECC;
83  	out_be32(ndfc->ndfcbase + NDFC_CCR, ccr);
84  	wmb();
85  }
86  
ndfc_calculate_ecc(struct nand_chip * chip,const u_char * dat,u_char * ecc_code)87  static int ndfc_calculate_ecc(struct nand_chip *chip,
88  			      const u_char *dat, u_char *ecc_code)
89  {
90  	struct ndfc_controller *ndfc = nand_get_controller_data(chip);
91  	uint32_t ecc;
92  	uint8_t *p = (uint8_t *)&ecc;
93  
94  	wmb();
95  	ecc = in_be32(ndfc->ndfcbase + NDFC_ECC);
96  	/* The NDFC uses Smart Media (SMC) bytes order */
97  	ecc_code[0] = p[1];
98  	ecc_code[1] = p[2];
99  	ecc_code[2] = p[3];
100  
101  	return 0;
102  }
103  
104  /*
105   * Speedups for buffer read/write/verify
106   *
107   * NDFC allows 32bit read/write of data. So we can speed up the buffer
108   * functions. No further checking, as nand_base will always read/write
109   * page aligned.
110   */
ndfc_read_buf(struct nand_chip * chip,uint8_t * buf,int len)111  static void ndfc_read_buf(struct nand_chip *chip, uint8_t *buf, int len)
112  {
113  	struct ndfc_controller *ndfc = nand_get_controller_data(chip);
114  	uint32_t *p = (uint32_t *) buf;
115  
116  	for(;len > 0; len -= 4)
117  		*p++ = in_be32(ndfc->ndfcbase + NDFC_DATA);
118  }
119  
ndfc_write_buf(struct nand_chip * chip,const uint8_t * buf,int len)120  static void ndfc_write_buf(struct nand_chip *chip, const uint8_t *buf, int len)
121  {
122  	struct ndfc_controller *ndfc = nand_get_controller_data(chip);
123  	uint32_t *p = (uint32_t *) buf;
124  
125  	for(;len > 0; len -= 4)
126  		out_be32(ndfc->ndfcbase + NDFC_DATA, *p++);
127  }
128  
129  /*
130   * Initialize chip structure
131   */
ndfc_chip_init(struct ndfc_controller * ndfc,struct device_node * node)132  static int ndfc_chip_init(struct ndfc_controller *ndfc,
133  			  struct device_node *node)
134  {
135  	struct device_node *flash_np;
136  	struct nand_chip *chip = &ndfc->chip;
137  	struct mtd_info *mtd = nand_to_mtd(chip);
138  	int ret;
139  
140  	chip->legacy.IO_ADDR_R = ndfc->ndfcbase + NDFC_DATA;
141  	chip->legacy.IO_ADDR_W = ndfc->ndfcbase + NDFC_DATA;
142  	chip->legacy.cmd_ctrl = ndfc_hwcontrol;
143  	chip->legacy.dev_ready = ndfc_ready;
144  	chip->legacy.select_chip = ndfc_select_chip;
145  	chip->legacy.chip_delay = 50;
146  	chip->controller = &ndfc->ndfc_control;
147  	chip->legacy.read_buf = ndfc_read_buf;
148  	chip->legacy.write_buf = ndfc_write_buf;
149  	chip->ecc.correct = rawnand_sw_hamming_correct;
150  	chip->ecc.hwctl = ndfc_enable_hwecc;
151  	chip->ecc.calculate = ndfc_calculate_ecc;
152  	chip->ecc.engine_type = NAND_ECC_ENGINE_TYPE_ON_HOST;
153  	chip->ecc.size = 256;
154  	chip->ecc.bytes = 3;
155  	chip->ecc.strength = 1;
156  	nand_set_controller_data(chip, ndfc);
157  
158  	mtd->dev.parent = &ndfc->ofdev->dev;
159  
160  	flash_np = of_get_next_child(node, NULL);
161  	if (!flash_np)
162  		return -ENODEV;
163  	nand_set_flash_node(chip, flash_np);
164  
165  	mtd->name = kasprintf(GFP_KERNEL, "%s.%pOFn", dev_name(&ndfc->ofdev->dev),
166  			      flash_np);
167  	if (!mtd->name) {
168  		ret = -ENOMEM;
169  		goto err;
170  	}
171  
172  	ret = nand_scan(chip, 1);
173  	if (ret)
174  		goto err;
175  
176  	ret = mtd_device_register(mtd, NULL, 0);
177  
178  err:
179  	of_node_put(flash_np);
180  	if (ret)
181  		kfree(mtd->name);
182  	return ret;
183  }
184  
ndfc_probe(struct platform_device * ofdev)185  static int ndfc_probe(struct platform_device *ofdev)
186  {
187  	struct ndfc_controller *ndfc;
188  	const __be32 *reg;
189  	u32 ccr;
190  	u32 cs;
191  	int err, len;
192  
193  	/* Read the reg property to get the chip select */
194  	reg = of_get_property(ofdev->dev.of_node, "reg", &len);
195  	if (reg == NULL || len != 12) {
196  		dev_err(&ofdev->dev, "unable read reg property (%d)\n", len);
197  		return -ENOENT;
198  	}
199  
200  	cs = be32_to_cpu(reg[0]);
201  	if (cs >= NDFC_MAX_CS) {
202  		dev_err(&ofdev->dev, "invalid CS number (%d)\n", cs);
203  		return -EINVAL;
204  	}
205  
206  	ndfc = &ndfc_ctrl[cs];
207  	ndfc->chip_select = cs;
208  
209  	nand_controller_init(&ndfc->ndfc_control);
210  	ndfc->ofdev = ofdev;
211  	dev_set_drvdata(&ofdev->dev, ndfc);
212  
213  	ndfc->ndfcbase = of_iomap(ofdev->dev.of_node, 0);
214  	if (!ndfc->ndfcbase) {
215  		dev_err(&ofdev->dev, "failed to get memory\n");
216  		return -EIO;
217  	}
218  
219  	ccr = NDFC_CCR_BS(ndfc->chip_select);
220  
221  	/* It is ok if ccr does not exist - just default to 0 */
222  	reg = of_get_property(ofdev->dev.of_node, "ccr", NULL);
223  	if (reg)
224  		ccr |= be32_to_cpup(reg);
225  
226  	out_be32(ndfc->ndfcbase + NDFC_CCR, ccr);
227  
228  	/* Set the bank settings if given */
229  	reg = of_get_property(ofdev->dev.of_node, "bank-settings", NULL);
230  	if (reg) {
231  		int offset = NDFC_BCFG0 + (ndfc->chip_select << 2);
232  		out_be32(ndfc->ndfcbase + offset, be32_to_cpup(reg));
233  	}
234  
235  	err = ndfc_chip_init(ndfc, ofdev->dev.of_node);
236  	if (err) {
237  		iounmap(ndfc->ndfcbase);
238  		return err;
239  	}
240  
241  	return 0;
242  }
243  
ndfc_remove(struct platform_device * ofdev)244  static void ndfc_remove(struct platform_device *ofdev)
245  {
246  	struct ndfc_controller *ndfc = dev_get_drvdata(&ofdev->dev);
247  	struct nand_chip *chip = &ndfc->chip;
248  	struct mtd_info *mtd = nand_to_mtd(chip);
249  	int ret;
250  
251  	ret = mtd_device_unregister(mtd);
252  	WARN_ON(ret);
253  	nand_cleanup(chip);
254  	kfree(mtd->name);
255  }
256  
257  static const struct of_device_id ndfc_match[] = {
258  	{ .compatible = "ibm,ndfc", },
259  	{}
260  };
261  MODULE_DEVICE_TABLE(of, ndfc_match);
262  
263  static struct platform_driver ndfc_driver = {
264  	.driver = {
265  		.name = "ndfc",
266  		.of_match_table = ndfc_match,
267  	},
268  	.probe = ndfc_probe,
269  	.remove_new = ndfc_remove,
270  };
271  
272  module_platform_driver(ndfc_driver);
273  
274  MODULE_LICENSE("GPL");
275  MODULE_AUTHOR("Thomas Gleixner <tglx@linutronix.de>");
276  MODULE_DESCRIPTION("OF Platform driver for NDFC");
277