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1/* elan-104nc.c -- MTD map driver for Arcom Control Systems ELAN-104NC
2
3 Copyright (C) 2000 Arcom Control System Ltd
4
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2 of the License, or
8 (at your option) any later version.
9
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
14
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software
17 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
18
19 $Id: elan-104nc.c,v 1.25 2004/11/28 09:40:39 dwmw2 Exp $
20
21The ELAN-104NC has up to 8 Mibyte of Intel StrataFlash (28F320/28F640) in x16
22mode. This drivers uses the CFI probe and Intel Extended Command Set drivers.
23
24The flash is accessed as follows:
25
26 32 kbyte memory window at 0xb0000-0xb7fff
27
28 16 bit I/O port (0x22) for some sort of paging.
29
30The single flash device is divided into 3 partition which appear as separate
31MTD devices.
32
33Linux thinks that the I/O port is used by the PIC and hence check_region() will
34always fail. So we don't do it. I just hope it doesn't break anything.
35*/
36#include <linux/module.h>
37#include <linux/slab.h>
38#include <linux/ioport.h>
39#include <linux/init.h>
40#include <asm/io.h>
41
42#include <linux/mtd/map.h>
43#include <linux/mtd/mtd.h>
44#include <linux/mtd/partitions.h>
45
46#define WINDOW_START 0xb0000
47/* Number of bits in offset. */
48#define WINDOW_SHIFT 15
49#define WINDOW_LENGTH (1 << WINDOW_SHIFT)
50/* The bits for the offset into the window. */
51#define WINDOW_MASK (WINDOW_LENGTH-1)
52#define PAGE_IO 0x22
53#define PAGE_IO_SIZE 2
54
55static volatile int page_in_window = -1; // Current page in window.
56static void __iomem *iomapadr;
57static DEFINE_SPINLOCK(elan_104nc_spin);
58
59/* partition_info gives details on the logical partitions that the split the
60 * single flash device into. If the size if zero we use up to the end of the
61 * device. */
62static struct mtd_partition partition_info[]={
63 { .name = "ELAN-104NC flash boot partition",
64 .offset = 0,
65 .size = 640*1024 },
66 { .name = "ELAN-104NC flash partition 1",
67 .offset = 640*1024,
68 .size = 896*1024 },
69 { .name = "ELAN-104NC flash partition 2",
70 .offset = (640+896)*1024 }
71};
72#define NUM_PARTITIONS (sizeof(partition_info)/sizeof(partition_info[0]))
73
74/*
75 * If no idea what is going on here. This is taken from the FlashFX stuff.
76 */
77#define ROMCS 1
78
79static inline void elan_104nc_setup(void)
80{
81 u16 t;
82
83 outw( 0x0023 + ROMCS*2, PAGE_IO );
84 t=inb( PAGE_IO+1 );
85
86 t=(t & 0xf9) | 0x04;
87
88 outw( ((0x0023 + ROMCS*2) | (t << 8)), PAGE_IO );
89}
90
91static inline void elan_104nc_page(struct map_info *map, unsigned long ofs)
92{
93 unsigned long page = ofs >> WINDOW_SHIFT;
94
95 if( page!=page_in_window ) {
96 int cmd1;
97 int cmd2;
98
99 cmd1=(page & 0x700) + 0x0833 + ROMCS*0x4000;
100 cmd2=((page & 0xff) << 8) + 0x0032;
101
102 outw( cmd1, PAGE_IO );
103 outw( cmd2, PAGE_IO );
104
105 page_in_window = page;
106 }
107}
108
109
110static map_word elan_104nc_read16(struct map_info *map, unsigned long ofs)
111{
112 map_word ret;
113 spin_lock(&elan_104nc_spin);
114 elan_104nc_page(map, ofs);
115 ret.x[0] = readw(iomapadr + (ofs & WINDOW_MASK));
116 spin_unlock(&elan_104nc_spin);
117 return ret;
118}
119
120static void elan_104nc_copy_from(struct map_info *map, void *to, unsigned long from, ssize_t len)
121{
122 while (len) {
123 unsigned long thislen = len;
124 if (len > (WINDOW_LENGTH - (from & WINDOW_MASK)))
125 thislen = WINDOW_LENGTH-(from & WINDOW_MASK);
126
127 spin_lock(&elan_104nc_spin);
128 elan_104nc_page(map, from);
129 memcpy_fromio(to, iomapadr + (from & WINDOW_MASK), thislen);
130 spin_unlock(&elan_104nc_spin);
131 to += thislen;
132 from += thislen;
133 len -= thislen;
134 }
135}
136
137static void elan_104nc_write16(struct map_info *map, map_word d, unsigned long adr)
138{
139 spin_lock(&elan_104nc_spin);
140 elan_104nc_page(map, adr);
141 writew(d.x[0], iomapadr + (adr & WINDOW_MASK));
142 spin_unlock(&elan_104nc_spin);
143}
144
145static void elan_104nc_copy_to(struct map_info *map, unsigned long to, const void *from, ssize_t len)
146{
147 while(len) {
148 unsigned long thislen = len;
149 if (len > (WINDOW_LENGTH - (to & WINDOW_MASK)))
150 thislen = WINDOW_LENGTH-(to & WINDOW_MASK);
151
152 spin_lock(&elan_104nc_spin);
153 elan_104nc_page(map, to);
154 memcpy_toio(iomapadr + (to & WINDOW_MASK), from, thislen);
155 spin_unlock(&elan_104nc_spin);
156 to += thislen;
157 from += thislen;
158 len -= thislen;
159 }
160}
161
162static struct map_info elan_104nc_map = {
163 .name = "ELAN-104NC flash",
164 .phys = NO_XIP,
165 .size = 8*1024*1024, /* this must be set to a maximum possible amount
166 of flash so the cfi probe routines find all
167 the chips */
168 .bankwidth = 2,
169 .read = elan_104nc_read16,
170 .copy_from = elan_104nc_copy_from,
171 .write = elan_104nc_write16,
172 .copy_to = elan_104nc_copy_to
173};
174
175/* MTD device for all of the flash. */
176static struct mtd_info *all_mtd;
177
178static void cleanup_elan_104nc(void)
179{
180 if( all_mtd ) {
181 del_mtd_partitions( all_mtd );
182 map_destroy( all_mtd );
183 }
184
185 iounmap(iomapadr);
186}
187
188static int __init init_elan_104nc(void)
189{
190 /* Urg! We use I/O port 0x22 without request_region()ing it,
191 because it's already allocated to the PIC. */
192
193 iomapadr = ioremap(WINDOW_START, WINDOW_LENGTH);
194 if (!iomapadr) {
195 printk( KERN_ERR"%s: failed to ioremap memory region\n",
196 elan_104nc_map.name );
197 return -EIO;
198 }
199
200 printk( KERN_INFO"%s: IO:0x%x-0x%x MEM:0x%x-0x%x\n",
201 elan_104nc_map.name,
202 PAGE_IO, PAGE_IO+PAGE_IO_SIZE-1,
203 WINDOW_START, WINDOW_START+WINDOW_LENGTH-1 );
204
205 elan_104nc_setup();
206
207 /* Probe for chip. */
208 all_mtd = do_map_probe("cfi_probe", &elan_104nc_map );
209 if( !all_mtd ) {
210 cleanup_elan_104nc();
211 return -ENXIO;
212 }
213
214 all_mtd->owner = THIS_MODULE;
215
216 /* Create MTD devices for each partition. */
217 add_mtd_partitions( all_mtd, partition_info, NUM_PARTITIONS );
218
219 return 0;
220}
221
222module_init(init_elan_104nc);
223module_exit(cleanup_elan_104nc);
224
225
226MODULE_LICENSE("GPL");
227MODULE_AUTHOR("Arcom Control Systems Ltd.");
228MODULE_DESCRIPTION("MTD map driver for Arcom Control Systems ELAN-104NC");