1 /*
2  *  drivers/mtd/nand/edb7312.c
3  *
4  *  Copyright (C) 2002 Marius Gröger (mag@sysgo.de)
5  *
6  *  Derived from drivers/mtd/nand/autcpu12.c
7  *       Copyright (c) 2001 Thomas Gleixner (gleixner@autronix.de)
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11  * published by the Free Software Foundation.
12  *
13  *  Overview:
14  *   This is a device driver for the NAND flash device found on the
15  *   CLEP7312 board which utilizes the Toshiba TC58V64AFT part. This is
16  *   a 64Mibit (8MiB x 8 bits) NAND flash device.
17  */
18 
19 #include <linux/slab.h>
20 #include <linux/module.h>
21 #include <linux/init.h>
22 #include <linux/mtd/mtd.h>
23 #include <linux/mtd/nand.h>
24 #include <linux/mtd/partitions.h>
25 #include <asm/io.h>
26 #include <mach/hardware.h>	/* for CLPS7111_VIRT_BASE */
27 #include <asm/sizes.h>
28 #include <asm/hardware/clps7111.h>
29 
30 /*
31  * MTD structure for EDB7312 board
32  */
33 static struct mtd_info *ep7312_mtd = NULL;
34 
35 /*
36  * Values specific to the EDB7312 board (used with EP7312 processor)
37  */
38 #define EP7312_FIO_PBASE 0x10000000	/* Phys address of flash */
39 #define EP7312_PXDR	0x0001	/*
40 				 * IO offset to Port B data register
41 				 * where the CLE, ALE and NCE pins
42 				 * are wired to.
43 				 */
44 #define EP7312_PXDDR	0x0041	/*
45 				 * IO offset to Port B data direction
46 				 * register so we can control the IO
47 				 * lines.
48 				 */
49 
50 /*
51  * Module stuff
52  */
53 
54 static unsigned long ep7312_fio_pbase = EP7312_FIO_PBASE;
55 static void __iomem *ep7312_pxdr = (void __iomem *)EP7312_PXDR;
56 static void __iomem *ep7312_pxddr = (void __iomem *)EP7312_PXDDR;
57 
58 #ifdef CONFIG_MTD_PARTITIONS
59 /*
60  * Define static partitions for flash device
61  */
62 static struct mtd_partition partition_info[] = {
63 	{.name = "EP7312 Nand Flash",
64 	 .offset = 0,
65 	 .size = 8 * 1024 * 1024}
66 };
67 
68 #define NUM_PARTITIONS 1
69 
70 #endif
71 
72 /*
73  *	hardware specific access to control-lines
74  *
75  *	NAND_NCE: bit 0 -> bit 6 (bit 7 = 1)
76  *	NAND_CLE: bit 1 -> bit 4
77  *	NAND_ALE: bit 2 -> bit 5
78  */
ep7312_hwcontrol(struct mtd_info * mtd,int cmd,unsigned int ctrl)79 static void ep7312_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int ctrl)
80 {
81 	struct nand_chip *chip = mtd->priv;
82 
83 	if (ctrl & NAND_CTRL_CHANGE) {
84 		unsigned char bits = 0x80;
85 
86 		bits |= (ctrl & (NAND_CLE | NAND_ALE)) << 3;
87 		bits |= (ctrl & NAND_NCE) ? 0x00 : 0x40;
88 
89 		clps_writeb((clps_readb(ep7312_pxdr)  & 0xF0) | bits,
90 			    ep7312_pxdr);
91 	}
92 	if (cmd != NAND_CMD_NONE)
93 		writeb(cmd, chip->IO_ADDR_W);
94 }
95 
96 /*
97  *	read device ready pin
98  */
ep7312_device_ready(struct mtd_info * mtd)99 static int ep7312_device_ready(struct mtd_info *mtd)
100 {
101 	return 1;
102 }
103 
104 #ifdef CONFIG_MTD_PARTITIONS
105 const char *part_probes[] = { "cmdlinepart", NULL };
106 #endif
107 
108 /*
109  * Main initialization routine
110  */
ep7312_init(void)111 static int __init ep7312_init(void)
112 {
113 	struct nand_chip *this;
114 	const char *part_type = 0;
115 	int mtd_parts_nb = 0;
116 	struct mtd_partition *mtd_parts = 0;
117 	void __iomem *ep7312_fio_base;
118 
119 	/* Allocate memory for MTD device structure and private data */
120 	ep7312_mtd = kmalloc(sizeof(struct mtd_info) + sizeof(struct nand_chip), GFP_KERNEL);
121 	if (!ep7312_mtd) {
122 		printk("Unable to allocate EDB7312 NAND MTD device structure.\n");
123 		return -ENOMEM;
124 	}
125 
126 	/* map physical address */
127 	ep7312_fio_base = ioremap(ep7312_fio_pbase, SZ_1K);
128 	if (!ep7312_fio_base) {
129 		printk("ioremap EDB7312 NAND flash failed\n");
130 		kfree(ep7312_mtd);
131 		return -EIO;
132 	}
133 
134 	/* Get pointer to private data */
135 	this = (struct nand_chip *)(&ep7312_mtd[1]);
136 
137 	/* Initialize structures */
138 	memset(ep7312_mtd, 0, sizeof(struct mtd_info));
139 	memset(this, 0, sizeof(struct nand_chip));
140 
141 	/* Link the private data with the MTD structure */
142 	ep7312_mtd->priv = this;
143 	ep7312_mtd->owner = THIS_MODULE;
144 
145 	/*
146 	 * Set GPIO Port B control register so that the pins are configured
147 	 * to be outputs for controlling the NAND flash.
148 	 */
149 	clps_writeb(0xf0, ep7312_pxddr);
150 
151 	/* insert callbacks */
152 	this->IO_ADDR_R = ep7312_fio_base;
153 	this->IO_ADDR_W = ep7312_fio_base;
154 	this->cmd_ctrl = ep7312_hwcontrol;
155 	this->dev_ready = ep7312_device_ready;
156 	/* 15 us command delay time */
157 	this->chip_delay = 15;
158 
159 	/* Scan to find existence of the device */
160 	if (nand_scan(ep7312_mtd, 1)) {
161 		iounmap((void *)ep7312_fio_base);
162 		kfree(ep7312_mtd);
163 		return -ENXIO;
164 	}
165 #ifdef CONFIG_MTD_PARTITIONS
166 	ep7312_mtd->name = "edb7312-nand";
167 	mtd_parts_nb = parse_mtd_partitions(ep7312_mtd, part_probes, &mtd_parts, 0);
168 	if (mtd_parts_nb > 0)
169 		part_type = "command line";
170 	else
171 		mtd_parts_nb = 0;
172 #endif
173 	if (mtd_parts_nb == 0) {
174 		mtd_parts = partition_info;
175 		mtd_parts_nb = NUM_PARTITIONS;
176 		part_type = "static";
177 	}
178 
179 	/* Register the partitions */
180 	printk(KERN_NOTICE "Using %s partition definition\n", part_type);
181 	add_mtd_partitions(ep7312_mtd, mtd_parts, mtd_parts_nb);
182 
183 	/* Return happy */
184 	return 0;
185 }
186 
187 module_init(ep7312_init);
188 
189 /*
190  * Clean up routine
191  */
ep7312_cleanup(void)192 static void __exit ep7312_cleanup(void)
193 {
194 	struct nand_chip *this = (struct nand_chip *)&ep7312_mtd[1];
195 
196 	/* Release resources, unregister device */
197 	nand_release(ap7312_mtd);
198 
199 	/* Release io resource */
200 	iounmap(this->IO_ADDR_R);
201 
202 	/* Free the MTD device structure */
203 	kfree(ep7312_mtd);
204 }
205 
206 module_exit(ep7312_cleanup);
207 
208 MODULE_LICENSE("GPL");
209 MODULE_AUTHOR("Marius Groeger <mag@sysgo.de>");
210 MODULE_DESCRIPTION("MTD map driver for Cogent EDB7312 board");
211