summaryrefslogtreecommitdiffstats
path: root/drivers/mtd/maps/elan-104nc.c
blob: e9465f5c069e630da54aa260f848efb659925a3d (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
/* elan-104nc.c -- MTD map driver for Arcom Control Systems ELAN-104NC
 
   Copyright (C) 2000 Arcom Control System Ltd
 
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.
 
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
 
   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA

   $Id: elan-104nc.c,v 1.25 2004/11/28 09:40:39 dwmw2 Exp $

The ELAN-104NC has up to 8 Mibyte of Intel StrataFlash (28F320/28F640) in x16
mode.  This drivers uses the CFI probe and Intel Extended Command Set drivers.

The flash is accessed as follows:

   32 kbyte memory window at 0xb0000-0xb7fff
   
   16 bit I/O port (0x22) for some sort of paging.

The single flash device is divided into 3 partition which appear as separate
MTD devices.

Linux thinks that the I/O port is used by the PIC and hence check_region() will
always fail.  So we don't do it.  I just hope it doesn't break anything.
*/
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/ioport.h>
#include <linux/init.h>
#include <asm/io.h>

#include <linux/mtd/map.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/partitions.h>

#define WINDOW_START 0xb0000
/* Number of bits in offset. */
#define WINDOW_SHIFT 15
#define WINDOW_LENGTH (1 << WINDOW_SHIFT)
/* The bits for the offset into the window. */
#define WINDOW_MASK (WINDOW_LENGTH-1)
#define PAGE_IO 0x22
#define PAGE_IO_SIZE 2

static volatile int page_in_window = -1; // Current page in window.
static void __iomem *iomapadr;
static DEFINE_SPINLOCK(elan_104nc_spin);

/* partition_info gives details on the logical partitions that the split the 
 * single flash device into. If the size if zero we use up to the end of the
 * device. */
static struct mtd_partition partition_info[]={
    { .name = "ELAN-104NC flash boot partition", 
      .offset = 0, 
      .size = 640*1024 },
    { .name = "ELAN-104NC flash partition 1", 
      .offset = 640*1024, 
      .size = 896*1024 },
    { .name = "ELAN-104NC flash partition 2", 
      .offset = (640+896)*1024 }
};
#define NUM_PARTITIONS (sizeof(partition_info)/sizeof(partition_info[0]))

/*
 * If no idea what is going on here.  This is taken from the FlashFX stuff.
 */
#define ROMCS 1

static inline void elan_104nc_setup(void)
{
    u16 t;

    outw( 0x0023 + ROMCS*2, PAGE_IO );
    t=inb( PAGE_IO+1 );

    t=(t & 0xf9) | 0x04;

    outw( ((0x0023 + ROMCS*2) | (t << 8)), PAGE_IO );
}

static inline void elan_104nc_page(struct map_info *map, unsigned long ofs)
{
	unsigned long page = ofs >> WINDOW_SHIFT;
       
	if( page!=page_in_window ) {
		int cmd1;
		int cmd2;

		cmd1=(page & 0x700) + 0x0833 + ROMCS*0x4000;
		cmd2=((page & 0xff) << 8) + 0x0032;

		outw( cmd1, PAGE_IO );
		outw( cmd2, PAGE_IO );

		page_in_window = page;
	}
}


static map_word elan_104nc_read16(struct map_info *map, unsigned long ofs)
{
	map_word ret;
	spin_lock(&elan_104nc_spin);
	elan_104nc_page(map, ofs);
	ret.x[0] = readw(iomapadr + (ofs & WINDOW_MASK));
	spin_unlock(&elan_104nc_spin);
	return ret;
}

static void elan_104nc_copy_from(struct map_info *map, void *to, unsigned long from, ssize_t len)
{
	while (len) {
		unsigned long thislen = len;
		if (len > (WINDOW_LENGTH - (from & WINDOW_MASK)))
			thislen = WINDOW_LENGTH-(from & WINDOW_MASK);
		
		spin_lock(&elan_104nc_spin);
		elan_104nc_page(map, from);
		memcpy_fromio(to, iomapadr + (from & WINDOW_MASK), thislen);
		spin_unlock(&elan_104nc_spin);
		to += thislen;
		from += thislen;
		len -= thislen;
	}
}

static void elan_104nc_write16(struct map_info *map, map_word d, unsigned long adr)
{
	spin_lock(&elan_104nc_spin);
	elan_104nc_page(map, adr);
	writew(d.x[0], iomapadr + (adr & WINDOW_MASK));
	spin_unlock(&elan_104nc_spin);
}

static void elan_104nc_copy_to(struct map_info *map, unsigned long to, const void *from, ssize_t len)
{	
	while(len) {
		unsigned long thislen = len;
		if (len > (WINDOW_LENGTH - (to & WINDOW_MASK)))
			thislen = WINDOW_LENGTH-(to & WINDOW_MASK);
		
		spin_lock(&elan_104nc_spin);
		elan_104nc_page(map, to);
		memcpy_toio(iomapadr + (to & WINDOW_MASK), from, thislen);
		spin_unlock(&elan_104nc_spin);
		to += thislen;
		from += thislen;
		len -= thislen;
	}
}

static struct map_info elan_104nc_map = {
	.name = "ELAN-104NC flash",
	.phys = NO_XIP,
	.size = 8*1024*1024, /* this must be set to a maximum possible amount
			of flash so the cfi probe routines find all
			the chips */
	.bankwidth = 2,
	.read = elan_104nc_read16,
	.copy_from = elan_104nc_copy_from,
	.write = elan_104nc_write16,
	.copy_to = elan_104nc_copy_to
};

/* MTD device for all of the flash. */
static struct mtd_info *all_mtd;

static void cleanup_elan_104nc(void)
{
	if( all_mtd ) {
		del_mtd_partitions( all_mtd );
		map_destroy( all_mtd );
	}

	iounmap(iomapadr);
}

static int __init init_elan_104nc(void)
{
	/* Urg! We use I/O port 0x22 without request_region()ing it,
	   because it's already allocated to the PIC. */

  	iomapadr = ioremap(WINDOW_START, WINDOW_LENGTH);
	if (!iomapadr) {
		printk( KERN_ERR"%s: failed to ioremap memory region\n",
			elan_104nc_map.name );
		return -EIO;
	}

	printk( KERN_INFO"%s: IO:0x%x-0x%x MEM:0x%x-0x%x\n",
		elan_104nc_map.name,
		PAGE_IO, PAGE_IO+PAGE_IO_SIZE-1,
		WINDOW_START, WINDOW_START+WINDOW_LENGTH-1 );

	elan_104nc_setup();

	/* Probe for chip. */
	all_mtd = do_map_probe("cfi_probe",  &elan_104nc_map );
	if( !all_mtd ) {
		cleanup_elan_104nc();
		return -ENXIO;
	}
	
	all_mtd->owner = THIS_MODULE;

	/* Create MTD devices for each partition. */
	add_mtd_partitions( all_mtd, partition_info, NUM_PARTITIONS );

	return 0;
}

module_init(init_elan_104nc);
module_exit(cleanup_elan_104nc);


MODULE_LICENSE("GPL");
MODULE_AUTHOR("Arcom Control Systems Ltd.");
MODULE_DESCRIPTION("MTD map driver for Arcom Control Systems ELAN-104NC");
OpenPOWER on IntegriCloud