summaryrefslogtreecommitdiffstats
path: root/drivers/mtd/nand/ams-delta.c
blob: 4936e9e0002f384701493e0cb823d73ee3f20fb6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
/*
 *  drivers/mtd/nand/ams-delta.c
 *
 *  Copyright (C) 2006 Jonathan McDowell <noodles@earth.li>
 *
 *  Derived from drivers/mtd/toto.c
 *  Converted to platform driver by Janusz Krzysztofik <jkrzyszt@tis.icnet.pl>
 *  Partially stolen from drivers/mtd/nand/plat_nand.c
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 *  Overview:
 *   This is a device driver for the NAND flash device found on the
 *   Amstrad E3 (Delta).
 */

#include <linux/slab.h>
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/nand.h>
#include <linux/mtd/partitions.h>
#include <linux/gpio.h>
#include <linux/platform_data/gpio-omap.h>

#include <asm/io.h>
#include <asm/sizes.h>

#include <mach/board-ams-delta.h>

#include <mach/hardware.h>

/*
 * MTD structure for E3 (Delta)
 */
static struct mtd_info *ams_delta_mtd = NULL;

/*
 * Define partitions for flash devices
 */

static struct mtd_partition partition_info[] = {
	{ .name		= "Kernel",
	  .offset	= 0,
	  .size		= 3 * SZ_1M + SZ_512K },
	{ .name		= "u-boot",
	  .offset	= 3 * SZ_1M + SZ_512K,
	  .size		= SZ_256K },
	{ .name		= "u-boot params",
	  .offset	= 3 * SZ_1M + SZ_512K + SZ_256K,
	  .size		= SZ_256K },
	{ .name		= "Amstrad LDR",
	  .offset	= 4 * SZ_1M,
	  .size		= SZ_256K },
	{ .name		= "File system",
	  .offset	= 4 * SZ_1M + 1 * SZ_256K,
	  .size		= 27 * SZ_1M },
	{ .name		= "PBL reserved",
	  .offset	= 32 * SZ_1M - 3 * SZ_256K,
	  .size		=  3 * SZ_256K },
};

static void ams_delta_write_byte(struct mtd_info *mtd, u_char byte)
{
	struct nand_chip *this = mtd->priv;
	void __iomem *io_base = this->priv;

	writew(0, io_base + OMAP_MPUIO_IO_CNTL);
	writew(byte, this->IO_ADDR_W);
	gpio_set_value(AMS_DELTA_GPIO_PIN_NAND_NWE, 0);
	ndelay(40);
	gpio_set_value(AMS_DELTA_GPIO_PIN_NAND_NWE, 1);
}

static u_char ams_delta_read_byte(struct mtd_info *mtd)
{
	u_char res;
	struct nand_chip *this = mtd->priv;
	void __iomem *io_base = this->priv;

	gpio_set_value(AMS_DELTA_GPIO_PIN_NAND_NRE, 0);
	ndelay(40);
	writew(~0, io_base + OMAP_MPUIO_IO_CNTL);
	res = readw(this->IO_ADDR_R);
	gpio_set_value(AMS_DELTA_GPIO_PIN_NAND_NRE, 1);

	return res;
}

static void ams_delta_write_buf(struct mtd_info *mtd, const u_char *buf,
				int len)
{
	int i;

	for (i=0; i<len; i++)
		ams_delta_write_byte(mtd, buf[i]);
}

static void ams_delta_read_buf(struct mtd_info *mtd, u_char *buf, int len)
{
	int i;

	for (i=0; i<len; i++)
		buf[i] = ams_delta_read_byte(mtd);
}

/*
 * Command control function
 *
 * ctrl:
 * NAND_NCE: bit 0 -> bit 2
 * NAND_CLE: bit 1 -> bit 7
 * NAND_ALE: bit 2 -> bit 6
 */
static void ams_delta_hwcontrol(struct mtd_info *mtd, int cmd,
				unsigned int ctrl)
{

	if (ctrl & NAND_CTRL_CHANGE) {
		gpio_set_value(AMS_DELTA_GPIO_PIN_NAND_NCE,
				(ctrl & NAND_NCE) == 0);
		gpio_set_value(AMS_DELTA_GPIO_PIN_NAND_CLE,
				(ctrl & NAND_CLE) != 0);
		gpio_set_value(AMS_DELTA_GPIO_PIN_NAND_ALE,
				(ctrl & NAND_ALE) != 0);
	}

	if (cmd != NAND_CMD_NONE)
		ams_delta_write_byte(mtd, cmd);
}

static int ams_delta_nand_ready(struct mtd_info *mtd)
{
	return gpio_get_value(AMS_DELTA_GPIO_PIN_NAND_RB);
}

static const struct gpio _mandatory_gpio[] = {
	{
		.gpio	= AMS_DELTA_GPIO_PIN_NAND_NCE,
		.flags	= GPIOF_OUT_INIT_HIGH,
		.label	= "nand_nce",
	},
	{
		.gpio	= AMS_DELTA_GPIO_PIN_NAND_NRE,
		.flags	= GPIOF_OUT_INIT_HIGH,
		.label	= "nand_nre",
	},
	{
		.gpio	= AMS_DELTA_GPIO_PIN_NAND_NWP,
		.flags	= GPIOF_OUT_INIT_HIGH,
		.label	= "nand_nwp",
	},
	{
		.gpio	= AMS_DELTA_GPIO_PIN_NAND_NWE,
		.flags	= GPIOF_OUT_INIT_HIGH,
		.label	= "nand_nwe",
	},
	{
		.gpio	= AMS_DELTA_GPIO_PIN_NAND_ALE,
		.flags	= GPIOF_OUT_INIT_LOW,
		.label	= "nand_ale",
	},
	{
		.gpio	= AMS_DELTA_GPIO_PIN_NAND_CLE,
		.flags	= GPIOF_OUT_INIT_LOW,
		.label	= "nand_cle",
	},
};

/*
 * Main initialization routine
 */
static int ams_delta_init(struct platform_device *pdev)
{
	struct nand_chip *this;
	struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	void __iomem *io_base;
	int err = 0;

	if (!res)
		return -ENXIO;

	/* Allocate memory for MTD device structure and private data */
	ams_delta_mtd = kmalloc(sizeof(struct mtd_info) +
				sizeof(struct nand_chip), GFP_KERNEL);
	if (!ams_delta_mtd) {
		printk (KERN_WARNING "Unable to allocate E3 NAND MTD device structure.\n");
		err = -ENOMEM;
		goto out;
	}

	ams_delta_mtd->owner = THIS_MODULE;

	/* Get pointer to private data */
	this = (struct nand_chip *) (&ams_delta_mtd[1]);

	/* Initialize structures */
	memset(ams_delta_mtd, 0, sizeof(struct mtd_info));
	memset(this, 0, sizeof(struct nand_chip));

	/* Link the private data with the MTD structure */
	ams_delta_mtd->priv = this;

	/*
	 * Don't try to request the memory region from here,
	 * it should have been already requested from the
	 * gpio-omap driver and requesting it again would fail.
	 */

	io_base = ioremap(res->start, resource_size(res));
	if (io_base == NULL) {
		dev_err(&pdev->dev, "ioremap failed\n");
		err = -EIO;
		goto out_free;
	}

	this->priv = io_base;

	/* Set address of NAND IO lines */
	this->IO_ADDR_R = io_base + OMAP_MPUIO_INPUT_LATCH;
	this->IO_ADDR_W = io_base + OMAP_MPUIO_OUTPUT;
	this->read_byte = ams_delta_read_byte;
	this->write_buf = ams_delta_write_buf;
	this->read_buf = ams_delta_read_buf;
	this->cmd_ctrl = ams_delta_hwcontrol;
	if (gpio_request(AMS_DELTA_GPIO_PIN_NAND_RB, "nand_rdy") == 0) {
		this->dev_ready = ams_delta_nand_ready;
	} else {
		this->dev_ready = NULL;
		printk(KERN_NOTICE "Couldn't request gpio for Delta NAND ready.\n");
	}
	/* 25 us command delay time */
	this->chip_delay = 30;
	this->ecc.mode = NAND_ECC_SOFT;

	platform_set_drvdata(pdev, io_base);

	/* Set chip enabled, but  */
	err = gpio_request_array(_mandatory_gpio, ARRAY_SIZE(_mandatory_gpio));
	if (err)
		goto out_gpio;

	/* Scan to find existence of the device */
	if (nand_scan(ams_delta_mtd, 1)) {
		err = -ENXIO;
		goto out_mtd;
	}

	/* Register the partitions */
	mtd_device_register(ams_delta_mtd, partition_info,
			    ARRAY_SIZE(partition_info));

	goto out;

 out_mtd:
	gpio_free_array(_mandatory_gpio, ARRAY_SIZE(_mandatory_gpio));
out_gpio:
	gpio_free(AMS_DELTA_GPIO_PIN_NAND_RB);
	iounmap(io_base);
out_free:
	kfree(ams_delta_mtd);
 out:
	return err;
}

/*
 * Clean up routine
 */
static int ams_delta_cleanup(struct platform_device *pdev)
{
	void __iomem *io_base = platform_get_drvdata(pdev);

	/* Release resources, unregister device */
	nand_release(ams_delta_mtd);

	gpio_free_array(_mandatory_gpio, ARRAY_SIZE(_mandatory_gpio));
	gpio_free(AMS_DELTA_GPIO_PIN_NAND_RB);
	iounmap(io_base);

	/* Free the MTD device structure */
	kfree(ams_delta_mtd);

	return 0;
}

static struct platform_driver ams_delta_nand_driver = {
	.probe		= ams_delta_init,
	.remove		= ams_delta_cleanup,
	.driver		= {
		.name	= "ams-delta-nand",
		.owner	= THIS_MODULE,
	},
};

module_platform_driver(ams_delta_nand_driver);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Jonathan McDowell <noodles@earth.li>");
MODULE_DESCRIPTION("Glue layer for NAND flash on Amstrad E3 (Delta)");
OpenPOWER on IntegriCloud