summaryrefslogtreecommitdiffstats
path: root/drivers/mtd/nand/edb7312.c
blob: 8400d0f6dada730b6d56463c72a8e9926a0a7663 (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
/*
 *  drivers/mtd/nand/edb7312.c
 *
 *  Copyright (C) 2002 Marius Gröger (mag@sysgo.de)
 *
 *  Derived from drivers/mtd/nand/autcpu12.c
 *       Copyright (c) 2001 Thomas Gleixner (gleixner@autronix.de)
 *
 * 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
 *   CLEP7312 board which utilizes the Toshiba TC58V64AFT part. This is
 *   a 64Mibit (8MiB x 8 bits) NAND flash device.
 */

#include <linux/slab.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/nand.h>
#include <linux/mtd/partitions.h>
#include <asm/io.h>
#include <mach/hardware.h>	/* for CLPS7111_VIRT_BASE */
#include <asm/sizes.h>
#include <asm/hardware/clps7111.h>

/*
 * MTD structure for EDB7312 board
 */
static struct mtd_info *ep7312_mtd = NULL;

/*
 * Values specific to the EDB7312 board (used with EP7312 processor)
 */
#define EP7312_FIO_PBASE 0x10000000	/* Phys address of flash */
#define EP7312_PXDR	0x0001	/*
				 * IO offset to Port B data register
				 * where the CLE, ALE and NCE pins
				 * are wired to.
				 */
#define EP7312_PXDDR	0x0041	/*
				 * IO offset to Port B data direction
				 * register so we can control the IO
				 * lines.
				 */

/*
 * Module stuff
 */

static unsigned long ep7312_fio_pbase = EP7312_FIO_PBASE;
static void __iomem *ep7312_pxdr = (void __iomem *)EP7312_PXDR;
static void __iomem *ep7312_pxddr = (void __iomem *)EP7312_PXDDR;

/*
 * Define static partitions for flash device
 */
static struct mtd_partition partition_info[] = {
	{.name = "EP7312 Nand Flash",
	 .offset = 0,
	 .size = 8 * 1024 * 1024}
};

#define NUM_PARTITIONS 1

/*
 *	hardware specific access to control-lines
 *
 *	NAND_NCE: bit 0 -> bit 6 (bit 7 = 1)
 *	NAND_CLE: bit 1 -> bit 4
 *	NAND_ALE: bit 2 -> bit 5
 */
static void ep7312_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int ctrl)
{
	struct nand_chip *chip = mtd->priv;

	if (ctrl & NAND_CTRL_CHANGE) {
		unsigned char bits = 0x80;

		bits |= (ctrl & (NAND_CLE | NAND_ALE)) << 3;
		bits |= (ctrl & NAND_NCE) ? 0x00 : 0x40;

		clps_writeb((clps_readb(ep7312_pxdr)  & 0xF0) | bits,
			    ep7312_pxdr);
	}
	if (cmd != NAND_CMD_NONE)
		writeb(cmd, chip->IO_ADDR_W);
}

/*
 *	read device ready pin
 */
static int ep7312_device_ready(struct mtd_info *mtd)
{
	return 1;
}

const char *part_probes[] = { "cmdlinepart", NULL };

/*
 * Main initialization routine
 */
static int __init ep7312_init(void)
{
	struct nand_chip *this;
	const char *part_type = 0;
	int mtd_parts_nb = 0;
	struct mtd_partition *mtd_parts = 0;
	void __iomem *ep7312_fio_base;

	/* Allocate memory for MTD device structure and private data */
	ep7312_mtd = kmalloc(sizeof(struct mtd_info) + sizeof(struct nand_chip), GFP_KERNEL);
	if (!ep7312_mtd) {
		printk("Unable to allocate EDB7312 NAND MTD device structure.\n");
		return -ENOMEM;
	}

	/* map physical address */
	ep7312_fio_base = ioremap(ep7312_fio_pbase, SZ_1K);
	if (!ep7312_fio_base) {
		printk("ioremap EDB7312 NAND flash failed\n");
		kfree(ep7312_mtd);
		return -EIO;
	}

	/* Get pointer to private data */
	this = (struct nand_chip *)(&ep7312_mtd[1]);

	/* Initialize structures */
	memset(ep7312_mtd, 0, sizeof(struct mtd_info));
	memset(this, 0, sizeof(struct nand_chip));

	/* Link the private data with the MTD structure */
	ep7312_mtd->priv = this;
	ep7312_mtd->owner = THIS_MODULE;

	/*
	 * Set GPIO Port B control register so that the pins are configured
	 * to be outputs for controlling the NAND flash.
	 */
	clps_writeb(0xf0, ep7312_pxddr);

	/* insert callbacks */
	this->IO_ADDR_R = ep7312_fio_base;
	this->IO_ADDR_W = ep7312_fio_base;
	this->cmd_ctrl = ep7312_hwcontrol;
	this->dev_ready = ep7312_device_ready;
	/* 15 us command delay time */
	this->chip_delay = 15;

	/* Scan to find existence of the device */
	if (nand_scan(ep7312_mtd, 1)) {
		iounmap((void *)ep7312_fio_base);
		kfree(ep7312_mtd);
		return -ENXIO;
	}
	ep7312_mtd->name = "edb7312-nand";
	mtd_parts_nb = parse_mtd_partitions(ep7312_mtd, part_probes, &mtd_parts, 0);
	if (mtd_parts_nb > 0)
		part_type = "command line";
	else
		mtd_parts_nb = 0;
	if (mtd_parts_nb == 0) {
		mtd_parts = partition_info;
		mtd_parts_nb = NUM_PARTITIONS;
		part_type = "static";
	}

	/* Register the partitions */
	printk(KERN_NOTICE "Using %s partition definition\n", part_type);
	mtd_device_register(ep7312_mtd, mtd_parts, mtd_parts_nb);

	/* Return happy */
	return 0;
}

module_init(ep7312_init);

/*
 * Clean up routine
 */
static void __exit ep7312_cleanup(void)
{
	struct nand_chip *this = (struct nand_chip *)&ep7312_mtd[1];

	/* Release resources, unregister device */
	nand_release(ap7312_mtd);

	/* Release io resource */
	iounmap(this->IO_ADDR_R);

	/* Free the MTD device structure */
	kfree(ep7312_mtd);
}

module_exit(ep7312_cleanup);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Marius Groeger <mag@sysgo.de>");
MODULE_DESCRIPTION("MTD map driver for Cogent EDB7312 board");
OpenPOWER on IntegriCloud