drivers/mtd/maps/sa1100-flash.c

   1 /*
   2  * Flash memory access on SA11x0 based devices
   3  *
   4  * (C) 2000 Nicolas Pitre <nico@fluxnic.net>
   5  */
   6 #include <linux/module.h>
   7 #include <linux/types.h>
   8 #include <linux/ioport.h>
   9 #include <linux/kernel.h>
  10 #include <linux/init.h>
  11 #include <linux/errno.h>
  12 #include <linux/slab.h>
  13 #include <linux/platform_device.h>
  14 #include <linux/err.h>
  15 #include <linux/io.h>
  16
  17 #include <linux/mtd/mtd.h>
  18 #include <linux/mtd/map.h>
  19 #include <linux/mtd/partitions.h>
  20 #include <linux/mtd/concat.h>
  21
  22 #include <mach/hardware.h>
  23 #include <asm/sizes.h>
  24 #include <asm/mach/flash.h>
  25
  26 struct sa_subdev_info {
  27         char name[16];
  28         struct map_info map;
  29         struct mtd_info *mtd;
  30         struct flash_platform_data *plat;
  31 };
  32
  33 struct sa_info {
  34         struct mtd_info         *mtd;
  35         int                     num_subdev;
  36         struct sa_subdev_info   subdev[0];
  37 };
  38
  39 static void sa1100_set_vpp(struct map_info *map, int on)
  40 {
  41         struct sa_subdev_info *subdev = container_of(map, struct sa_subdev_info, map);
  42         subdev->plat->set_vpp(on);
  43 }
  44
  45 static void sa1100_destroy_subdev(struct sa_subdev_info *subdev)
  46 {
  47         if (subdev->mtd)
  48                 map_destroy(subdev->mtd);
  49         if (subdev->map.virt)
  50                 iounmap(subdev->map.virt);
  51         release_mem_region(subdev->map.phys, subdev->map.size);
  52 }
  53
  54 static int sa1100_probe_subdev(struct sa_subdev_info *subdev, struct resource *res)
  55 {
  56         unsigned long phys;
  57         unsigned int size;
  58         int ret;
  59
  60         phys = res->start;
  61         size = res->end - phys + 1;
  62
  63         /*
  64          * Retrieve the bankwidth from the MSC registers.
  65          * We currently only implement CS0 and CS1 here.
  66          */
  67         switch (phys) {
  68         default:
  69                 printk(KERN_WARNING "SA1100 flash: unknown base address "
  70                        "0x%08lx, assuming CS0\n", phys);
  71
  72         case SA1100_CS0_PHYS:
  73                 subdev->map.bankwidth = (MSC0 & MSC_RBW) ? 2 : 4;
  74                 break;
  75
  76         case SA1100_CS1_PHYS:
  77                 subdev->map.bankwidth = ((MSC0 >> 16) & MSC_RBW) ? 2 : 4;
  78                 break;
  79         }
  80
  81         if (!request_mem_region(phys, size, subdev->name)) {
  82                 ret = -EBUSY;
  83                 goto out;
  84         }
  85
  86         if (subdev->plat->set_vpp)
  87                 subdev->map.set_vpp = sa1100_set_vpp;
  88
  89         subdev->map.phys = phys;
  90         subdev->map.size = size;
  91         subdev->map.virt = ioremap(phys, size);
  92         if (!subdev->map.virt) {
  93                 ret = -ENOMEM;
  94                 goto err;
  95         }
  96
  97         simple_map_init(&subdev->map);
  98
  99         /*
 100          * Now let's probe for the actual flash.  Do it here since
 101          * specific machine settings might have been set above.
 102          */
 103         subdev->mtd = do_map_probe(subdev->plat->map_name, &subdev->map);
 104         if (subdev->mtd == NULL) {
 105                 ret = -ENXIO;
 106                 goto err;
 107         }
 108         subdev->mtd->owner = THIS_MODULE;
 109
 110         printk(KERN_INFO "SA1100 flash: CFI device at 0x%08lx, %uMiB, %d-bit\n",
 111                 phys, (unsigned)(subdev->mtd->size >> 20),
 112                 subdev->map.bankwidth * 8);
 113
 114         return 0;
 115
 116  err:
 117         sa1100_destroy_subdev(subdev);
 118  out:
 119         return ret;
 120 }
 121
 122 static void sa1100_destroy(struct sa_info *info, struct flash_platform_data *plat)
 123 {
 124         int i;
 125
 126         if (info->mtd) {
 127                 mtd_device_unregister(info->mtd);
 128                 if (info->mtd != info->subdev[0].mtd)
 129                         mtd_concat_destroy(info->mtd);
 130         }
 131
 132         for (i = info->num_subdev - 1; i >= 0; i--)
 133                 sa1100_destroy_subdev(&info->subdev[i]);
 134         kfree(info);
 135
 136         if (plat->exit)
 137                 plat->exit();
 138 }
 139
 140 static struct sa_info *__devinit
 141 sa1100_setup_mtd(struct platform_device *pdev, struct flash_platform_data *plat)
 142 {
 143         struct sa_info *info;
 144         int nr, size, i, ret = 0;
 145
 146         /*
 147          * Count number of devices.
 148          */
 149         for (nr = 0; ; nr++)
 150                 if (!platform_get_resource(pdev, IORESOURCE_MEM, nr))
 151                         break;
 152
 153         if (nr == 0) {
 154                 ret = -ENODEV;
 155                 goto out;
 156         }
 157
 158         size = sizeof(struct sa_info) + sizeof(struct sa_subdev_info) * nr;
 159
 160         /*
 161          * Allocate the map_info structs in one go.
 162          */
 163         info = kzalloc(size, GFP_KERNEL);
 164         if (!info) {
 165                 ret = -ENOMEM;
 166                 goto out;
 167         }
 168
 169         if (plat->init) {
 170                 ret = plat->init();
 171                 if (ret)
 172                         goto err;
 173         }
 174
 175         /*
 176          * Claim and then map the memory regions.
 177          */
 178         for (i = 0; i < nr; i++) {
 179                 struct sa_subdev_info *subdev = &info->subdev[i];
 180                 struct resource *res;
 181
 182                 res = platform_get_resource(pdev, IORESOURCE_MEM, i);
 183                 if (!res)
 184                         break;
 185
 186                 subdev->map.name = subdev->name;
 187                 sprintf(subdev->name, "%s-%d", plat->name, i);
 188                 subdev->plat = plat;
 189
 190                 ret = sa1100_probe_subdev(subdev, res);
 191                 if (ret)
 192                         break;
 193         }
 194
 195         info->num_subdev = i;
 196
 197         /*
 198          * ENXIO is special.  It means we didn't find a chip when we probed.
 199          */
 200         if (ret != 0 && !(ret == -ENXIO && info->num_subdev > 0))
 201                 goto err;
 202
 203         /*
 204          * If we found one device, don't bother with concat support.  If
 205          * we found multiple devices, use concat if we have it available,
 206          * otherwise fail.  Either way, it'll be called "sa1100".
 207          */
 208         if (info->num_subdev == 1) {
 209                 strcpy(info->subdev[0].name, plat->name);
 210                 info->mtd = info->subdev[0].mtd;
 211                 ret = 0;
 212         } else if (info->num_subdev > 1) {
 213                 struct mtd_info *cdev[nr];
 214                 /*
 215                  * We detected multiple devices.  Concatenate them together.
 216                  */
 217                 for (i = 0; i < info->num_subdev; i++)
 218                         cdev[i] = info->subdev[i].mtd;
 219
 220                 info->mtd = mtd_concat_create(cdev, info->num_subdev,
 221                                               plat->name);
 222                 if (info->mtd == NULL)
 223                         ret = -ENXIO;
 224         }
 225
 226         if (ret == 0)
 227                 return info;
 228
 229  err:
 230         sa1100_destroy(info, plat);
 231  out:
 232         return ERR_PTR(ret);
 233 }
 234
 235 static const char *part_probes[] = { "cmdlinepart", "RedBoot", NULL };
 236
 237 static int __devinit sa1100_mtd_probe(struct platform_device *pdev)
 238 {
 239         struct flash_platform_data *plat = pdev->dev.platform_data;
 240         struct sa_info *info;
 241         int err;
 242
 243         if (!plat)
 244                 return -ENODEV;
 245
 246         info = sa1100_setup_mtd(pdev, plat);
 247         if (IS_ERR(info)) {
 248                 err = PTR_ERR(info);
 249                 goto out;
 250         }
 251
 252         /*
 253          * Partition selection stuff.
 254          */
 255         mtd_device_parse_register(info->mtd, part_probes, 0,
 256                         plat->parts, plat->nr_parts);
 257
 258         platform_set_drvdata(pdev, info);
 259         err = 0;
 260
 261  out:
 262         return err;
 263 }
 264
 265 static int __exit sa1100_mtd_remove(struct platform_device *pdev)
 266 {
 267         struct sa_info *info = platform_get_drvdata(pdev);
 268         struct flash_platform_data *plat = pdev->dev.platform_data;
 269
 270         platform_set_drvdata(pdev, NULL);
 271         sa1100_destroy(info, plat);
 272
 273         return 0;
 274 }
 275
 276 static struct platform_driver sa1100_mtd_driver = {
 277         .probe          = sa1100_mtd_probe,
 278         .remove         = __exit_p(sa1100_mtd_remove),
 279         .driver         = {
 280                 .name   = "sa1100-mtd",
 281                 .owner  = THIS_MODULE,
 282         },
 283 };
 284
 285 module_platform_driver(sa1100_mtd_driver);
 286
 287 MODULE_AUTHOR("Nicolas Pitre");
 288 MODULE_DESCRIPTION("SA1100 CFI map driver");
 289 MODULE_LICENSE("GPL");
 290 MODULE_ALIAS("platform:sa1100-mtd");