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 DEFINE_SPINLOCK(sa1100_vpp_lock); 40 static int sa1100_vpp_refcnt; 41 static void sa1100_set_vpp(struct map_info *map, int on) 42 { 43 struct sa_subdev_info *subdev = container_of(map, struct sa_subdev_info, map); 44 unsigned long flags; 45 46 spin_lock_irqsave(&sa1100_vpp_lock, flags); 47 if (on) { 48 if (++sa1100_vpp_refcnt == 1) /* first nested 'on' */ 49 subdev->plat->set_vpp(1); 50 } else { 51 if (--sa1100_vpp_refcnt == 0) /* last nested 'off' */ 52 subdev->plat->set_vpp(0); 53 } 54 spin_unlock_irqrestore(&sa1100_vpp_lock, flags); 55 } 56 57 static void sa1100_destroy_subdev(struct sa_subdev_info *subdev) 58 { 59 if (subdev->mtd) 60 map_destroy(subdev->mtd); 61 if (subdev->map.virt) 62 iounmap(subdev->map.virt); 63 release_mem_region(subdev->map.phys, subdev->map.size); 64 } 65 66 static int sa1100_probe_subdev(struct sa_subdev_info *subdev, struct resource *res) 67 { 68 unsigned long phys; 69 unsigned int size; 70 int ret; 71 72 phys = res->start; 73 size = res->end - phys + 1; 74 75 /* 76 * Retrieve the bankwidth from the MSC registers. 77 * We currently only implement CS0 and CS1 here. 78 */ 79 switch (phys) { 80 default: 81 printk(KERN_WARNING "SA1100 flash: unknown base address " 82 "0x%08lx, assuming CS0\n", phys); 83 84 case SA1100_CS0_PHYS: 85 subdev->map.bankwidth = (MSC0 & MSC_RBW) ? 2 : 4; 86 break; 87 88 case SA1100_CS1_PHYS: 89 subdev->map.bankwidth = ((MSC0 >> 16) & MSC_RBW) ? 2 : 4; 90 break; 91 } 92 93 if (!request_mem_region(phys, size, subdev->name)) { 94 ret = -EBUSY; 95 goto out; 96 } 97 98 if (subdev->plat->set_vpp) 99 subdev->map.set_vpp = sa1100_set_vpp; 100 101 subdev->map.phys = phys; 102 subdev->map.size = size; 103 subdev->map.virt = ioremap(phys, size); 104 if (!subdev->map.virt) { 105 ret = -ENOMEM; 106 goto err; 107 } 108 109 simple_map_init(&subdev->map); 110 111 /* 112 * Now let's probe for the actual flash. Do it here since 113 * specific machine settings might have been set above. 114 */ 115 subdev->mtd = do_map_probe(subdev->plat->map_name, &subdev->map); 116 if (subdev->mtd == NULL) { 117 ret = -ENXIO; 118 goto err; 119 } 120 121 printk(KERN_INFO "SA1100 flash: CFI device at 0x%08lx, %uMiB, %d-bit\n", 122 phys, (unsigned)(subdev->mtd->size >> 20), 123 subdev->map.bankwidth * 8); 124 125 return 0; 126 127 err: 128 sa1100_destroy_subdev(subdev); 129 out: 130 return ret; 131 } 132 133 static void sa1100_destroy(struct sa_info *info, struct flash_platform_data *plat) 134 { 135 int i; 136 137 if (info->mtd) { 138 mtd_device_unregister(info->mtd); 139 if (info->mtd != info->subdev[0].mtd) 140 mtd_concat_destroy(info->mtd); 141 } 142 143 for (i = info->num_subdev - 1; i >= 0; i--) 144 sa1100_destroy_subdev(&info->subdev[i]); 145 kfree(info); 146 147 if (plat->exit) 148 plat->exit(); 149 } 150 151 static struct sa_info *sa1100_setup_mtd(struct platform_device *pdev, 152 struct flash_platform_data *plat) 153 { 154 struct sa_info *info; 155 int nr, size, i, ret = 0; 156 157 /* 158 * Count number of devices. 159 */ 160 for (nr = 0; ; nr++) 161 if (!platform_get_resource(pdev, IORESOURCE_MEM, nr)) 162 break; 163 164 if (nr == 0) { 165 ret = -ENODEV; 166 goto out; 167 } 168 169 size = sizeof(struct sa_info) + sizeof(struct sa_subdev_info) * nr; 170 171 /* 172 * Allocate the map_info structs in one go. 173 */ 174 info = kzalloc(size, GFP_KERNEL); 175 if (!info) { 176 ret = -ENOMEM; 177 goto out; 178 } 179 180 if (plat->init) { 181 ret = plat->init(); 182 if (ret) 183 goto err; 184 } 185 186 /* 187 * Claim and then map the memory regions. 188 */ 189 for (i = 0; i < nr; i++) { 190 struct sa_subdev_info *subdev = &info->subdev[i]; 191 struct resource *res; 192 193 res = platform_get_resource(pdev, IORESOURCE_MEM, i); 194 if (!res) 195 break; 196 197 subdev->map.name = subdev->name; 198 sprintf(subdev->name, "%s-%d", plat->name, i); 199 subdev->plat = plat; 200 201 ret = sa1100_probe_subdev(subdev, res); 202 if (ret) 203 break; 204 } 205 206 info->num_subdev = i; 207 208 /* 209 * ENXIO is special. It means we didn't find a chip when we probed. 210 */ 211 if (ret != 0 && !(ret == -ENXIO && info->num_subdev > 0)) 212 goto err; 213 214 /* 215 * If we found one device, don't bother with concat support. If 216 * we found multiple devices, use concat if we have it available, 217 * otherwise fail. Either way, it'll be called "sa1100". 218 */ 219 if (info->num_subdev == 1) { 220 strcpy(info->subdev[0].name, plat->name); 221 info->mtd = info->subdev[0].mtd; 222 ret = 0; 223 } else if (info->num_subdev > 1) { 224 struct mtd_info *cdev[nr]; 225 /* 226 * We detected multiple devices. Concatenate them together. 227 */ 228 for (i = 0; i < info->num_subdev; i++) 229 cdev[i] = info->subdev[i].mtd; 230 231 info->mtd = mtd_concat_create(cdev, info->num_subdev, 232 plat->name); 233 if (info->mtd == NULL) { 234 ret = -ENXIO; 235 goto err; 236 } 237 } 238 info->mtd->dev.parent = &pdev->dev; 239 240 if (ret == 0) 241 return info; 242 243 err: 244 sa1100_destroy(info, plat); 245 out: 246 return ERR_PTR(ret); 247 } 248 249 static const char * const part_probes[] = { "cmdlinepart", "RedBoot", NULL }; 250 251 static int sa1100_mtd_probe(struct platform_device *pdev) 252 { 253 struct flash_platform_data *plat = dev_get_platdata(&pdev->dev); 254 struct sa_info *info; 255 int err; 256 257 if (!plat) 258 return -ENODEV; 259 260 info = sa1100_setup_mtd(pdev, plat); 261 if (IS_ERR(info)) { 262 err = PTR_ERR(info); 263 goto out; 264 } 265 266 /* 267 * Partition selection stuff. 268 */ 269 mtd_device_parse_register(info->mtd, part_probes, NULL, plat->parts, 270 plat->nr_parts); 271 272 platform_set_drvdata(pdev, info); 273 err = 0; 274 275 out: 276 return err; 277 } 278 279 static int sa1100_mtd_remove(struct platform_device *pdev) 280 { 281 struct sa_info *info = platform_get_drvdata(pdev); 282 struct flash_platform_data *plat = dev_get_platdata(&pdev->dev); 283 284 sa1100_destroy(info, plat); 285 286 return 0; 287 } 288 289 static struct platform_driver sa1100_mtd_driver = { 290 .probe = sa1100_mtd_probe, 291 .remove = sa1100_mtd_remove, 292 .driver = { 293 .name = "sa1100-mtd", 294 }, 295 }; 296 297 module_platform_driver(sa1100_mtd_driver); 298 299 MODULE_AUTHOR("Nicolas Pitre"); 300 MODULE_DESCRIPTION("SA1100 CFI map driver"); 301 MODULE_LICENSE("GPL"); 302 MODULE_ALIAS("platform:sa1100-mtd"); 303