drivers/mtd/maps/elan-104nc.c

   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
  21 The ELAN-104NC has up to 8 Mibyte of Intel StrataFlash (28F320/28F640) in x16
  22 mode.  This drivers uses the CFI probe and Intel Extended Command Set drivers.
  23
  24 The 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
  30 The single flash device is divided into 3 partition which appear as separate
  31 MTD devices.
  32
  33 Linux thinks that the I/O port is used by the PIC and hence check_region() will
  34 always 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
  55 static volatile int page_in_window = -1; // Current page in window.
  56 static void __iomem *iomapadr;
  57 static 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. */
  62 static 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
  79 static 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
  91 static 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
 110 static 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
 120 static 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
 137 static 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
 145 static 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
 162 static 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. */
 176 static struct mtd_info *all_mtd;
 177
 178 static 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
 188 static 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
 222 module_init(init_elan_104nc);
 223 module_exit(cleanup_elan_104nc);
 224
 225
 226 MODULE_LICENSE("GPL");
 227 MODULE_AUTHOR("Arcom Control Systems Ltd.");
 228 MODULE_DESCRIPTION("MTD map driver for Arcom Control Systems ELAN-104NC");