1 /*
2  *  drivers/mtd/nand/spia.c
3  *
4  *  Copyright (C) 2000 Steven J. Hill (sjhill@realitydiluted.com)
5  *
6  *
7  *	10-29-2001 TG	change to support hardwarespecific access
8  *			to controllines	(due to change in nand.c)
9  *			page_cache added
10  *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License version 2 as
13  * published by the Free Software Foundation.
14  *
15  *  Overview:
16  *   This is a device driver for the NAND flash device found on the
17  *   SPIA board which utilizes the Toshiba TC58V64AFT part. This is
18  *   a 64Mibit (8MiB x 8 bits) NAND flash device.
19  */
20 
21 #include <linux/kernel.h>
22 #include <linux/init.h>
23 #include <linux/slab.h>
24 #include <linux/module.h>
25 #include <linux/mtd/mtd.h>
26 #include <linux/mtd/nand.h>
27 #include <linux/mtd/partitions.h>
28 #include <asm/io.h>
29 
30 /*
31  * MTD structure for SPIA board
32  */
33 static struct mtd_info *spia_mtd = NULL;
34 
35 /*
36  * Values specific to the SPIA board (used with EP7212 processor)
37  */
38 #define SPIA_IO_BASE	0xd0000000	/* Start of EP7212 IO address space */
39 #define SPIA_FIO_BASE	0xf0000000	/* Address where flash is mapped */
40 #define SPIA_PEDR	0x0080	/*
41 				 * IO offset to Port E data register
42 				 * where the CLE, ALE and NCE pins
43 				 * are wired to.
44 				 */
45 #define SPIA_PEDDR	0x00c0	/*
46 				 * IO offset to Port E data direction
47 				 * register so we can control the IO
48 				 * lines.
49 				 */
50 
51 /*
52  * Module stuff
53  */
54 
55 static int spia_io_base = SPIA_IO_BASE;
56 static int spia_fio_base = SPIA_FIO_BASE;
57 static int spia_pedr = SPIA_PEDR;
58 static int spia_peddr = SPIA_PEDDR;
59 
60 module_param(spia_io_base, int, 0);
61 module_param(spia_fio_base, int, 0);
62 module_param(spia_pedr, int, 0);
63 module_param(spia_peddr, int, 0);
64 
65 /*
66  * Define partitions for flash device
67  */
68 static const struct mtd_partition partition_info[] = {
69 	{
70 	 .name = "SPIA flash partition 1",
71 	 .offset = 0,
72 	 .size = 2 * 1024 * 1024},
73 	{
74 	 .name = "SPIA flash partition 2",
75 	 .offset = 2 * 1024 * 1024,
76 	 .size = 6 * 1024 * 1024}
77 };
78 
79 #define NUM_PARTITIONS 2
80 
81 /*
82  *	hardware specific access to control-lines
83  *
84  *	ctrl:
85  *	NAND_CNE: bit 0 -> bit 2
86  *	NAND_CLE: bit 1 -> bit 0
87  *	NAND_ALE: bit 2 -> bit 1
88  */
spia_hwcontrol(struct mtd_info * mtd,int cmd)89 static void spia_hwcontrol(struct mtd_info *mtd, int cmd)
90 {
91 	struct nand_chip *chip = mtd->priv;
92 
93 	if (ctrl & NAND_CTRL_CHANGE) {
94 		void __iomem *addr = spia_io_base + spia_pedr;
95 		unsigned char bits;
96 
97 		bits = (ctrl & NAND_CNE) << 2;
98 		bits |= (ctrl & NAND_CLE | NAND_ALE) >> 1;
99 		writeb((readb(addr) & ~0x7) | bits, addr);
100 	}
101 
102 	if (cmd != NAND_CMD_NONE)
103 		writeb(cmd, chip->IO_ADDR_W);
104 }
105 
106 /*
107  * Main initialization routine
108  */
spia_init(void)109 static int __init spia_init(void)
110 {
111 	struct nand_chip *this;
112 
113 	/* Allocate memory for MTD device structure and private data */
114 	spia_mtd = kmalloc(sizeof(struct mtd_info) + sizeof(struct nand_chip), GFP_KERNEL);
115 	if (!spia_mtd) {
116 		printk("Unable to allocate SPIA NAND MTD device structure.\n");
117 		return -ENOMEM;
118 	}
119 
120 	/* Get pointer to private data */
121 	this = (struct nand_chip *)(&spia_mtd[1]);
122 
123 	/* Initialize structures */
124 	memset(spia_mtd, 0, sizeof(struct mtd_info));
125 	memset(this, 0, sizeof(struct nand_chip));
126 
127 	/* Link the private data with the MTD structure */
128 	spia_mtd->priv = this;
129 	spia_mtd->owner = THIS_MODULE;
130 
131 	/*
132 	 * Set GPIO Port E control register so that the pins are configured
133 	 * to be outputs for controlling the NAND flash.
134 	 */
135 	(*(volatile unsigned char *)(spia_io_base + spia_peddr)) = 0x07;
136 
137 	/* Set address of NAND IO lines */
138 	this->IO_ADDR_R = (void __iomem *)spia_fio_base;
139 	this->IO_ADDR_W = (void __iomem *)spia_fio_base;
140 	/* Set address of hardware control function */
141 	this->cmd_ctrl = spia_hwcontrol;
142 	/* 15 us command delay time */
143 	this->chip_delay = 15;
144 
145 	/* Scan to find existence of the device */
146 	if (nand_scan(spia_mtd, 1)) {
147 		kfree(spia_mtd);
148 		return -ENXIO;
149 	}
150 
151 	/* Register the partitions */
152 	mtd_device_register(spia_mtd, partition_info, NUM_PARTITIONS);
153 
154 	/* Return happy */
155 	return 0;
156 }
157 
158 module_init(spia_init);
159 
160 /*
161  * Clean up routine
162  */
spia_cleanup(void)163 static void __exit spia_cleanup(void)
164 {
165 	/* Release resources, unregister device */
166 	nand_release(spia_mtd);
167 
168 	/* Free the MTD device structure */
169 	kfree(spia_mtd);
170 }
171 
172 module_exit(spia_cleanup);
173 
174 MODULE_LICENSE("GPL");
175 MODULE_AUTHOR("Steven J. Hill <sjhill@realitydiluted.com");
176 MODULE_DESCRIPTION("Board-specific glue layer for NAND flash on SPIA board");
177