1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Flash memory access on SA11x0 based devices 4 * 5 * (C) 2000 Nicolas Pitre <nico@fluxnic.net> 6 */ 7 #include <linux/module.h> 8 #include <linux/types.h> 9 #include <linux/ioport.h> 10 #include <linux/kernel.h> 11 #include <linux/init.h> 12 #include <linux/errno.h> 13 #include <linux/slab.h> 14 #include <linux/platform_device.h> 15 #include <linux/err.h> 16 #include <linux/io.h> 17 18 #include <linux/mtd/mtd.h> 19 #include <linux/mtd/map.h> 20 #include <linux/mtd/partitions.h> 21 #include <linux/mtd/concat.h> 22 23 #include <mach/hardware.h> 24 #include <linux/sizes.h> 25 #include <asm/mach/flash.h> 26 27 struct sa_subdev_info { 28 char name[16]; 29 struct map_info map; 30 struct mtd_info *mtd; 31 struct flash_platform_data *plat; 32 }; 33 34 struct sa_info { 35 struct mtd_info *mtd; 36 int num_subdev; 37 struct sa_subdev_info subdev[0]; 38 }; 39 40 static DEFINE_SPINLOCK(sa1100_vpp_lock); 41 static int sa1100_vpp_refcnt; 42 static void sa1100_set_vpp(struct map_info *map, int on) 43 { 44 struct sa_subdev_info *subdev = container_of(map, struct sa_subdev_info, map); 45 unsigned long flags; 46 47 spin_lock_irqsave(&sa1100_vpp_lock, flags); 48 if (on) { 49 if (++sa1100_vpp_refcnt == 1) /* first nested 'on' */ 50 subdev->plat->set_vpp(1); 51 } else { 52 if (--sa1100_vpp_refcnt == 0) /* last nested 'off' */ 53 subdev->plat->set_vpp(0); 54 } 55 spin_unlock_irqrestore(&sa1100_vpp_lock, flags); 56 } 57 58 static void sa1100_destroy_subdev(struct sa_subdev_info *subdev) 59 { 60 if (subdev->mtd) 61 map_destroy(subdev->mtd); 62 if (subdev->map.virt) 63 iounmap(subdev->map.virt); 64 release_mem_region(subdev->map.phys, subdev->map.size); 65 } 66 67 static int sa1100_probe_subdev(struct sa_subdev_info *subdev, struct resource *res) 68 { 69 unsigned long phys; 70 unsigned int size; 71 int ret; 72 73 phys = res->start; 74 size = res->end - phys + 1; 75 76 /* 77 * Retrieve the bankwidth from the MSC registers. 78 * We currently only implement CS0 and CS1 here. 79 */ 80 switch (phys) { 81 default: 82 printk(KERN_WARNING "SA1100 flash: unknown base address " 83 "0x%08lx, assuming CS0\n", phys); 84 /* Fall through */ 85 86 case SA1100_CS0_PHYS: 87 subdev->map.bankwidth = (MSC0 & MSC_RBW) ? 2 : 4; 88 break; 89 90 case SA1100_CS1_PHYS: 91 subdev->map.bankwidth = ((MSC0 >> 16) & MSC_RBW) ? 2 : 4; 92 break; 93 } 94 95 if (!request_mem_region(phys, size, subdev->name)) { 96 ret = -EBUSY; 97 goto out; 98 } 99 100 if (subdev->plat->set_vpp) 101 subdev->map.set_vpp = sa1100_set_vpp; 102 103 subdev->map.phys = phys; 104 subdev->map.size = size; 105 subdev->map.virt = ioremap(phys, size); 106 if (!subdev->map.virt) { 107 ret = -ENOMEM; 108 goto err; 109 } 110 111 simple_map_init(&subdev->map); 112 113 /* 114 * Now let's probe for the actual flash. Do it here since 115 * specific machine settings might have been set above. 116 */ 117 subdev->mtd = do_map_probe(subdev->plat->map_name, &subdev->map); 118 if (subdev->mtd == NULL) { 119 ret = -ENXIO; 120 goto err; 121 } 122 123 printk(KERN_INFO "SA1100 flash: CFI device at 0x%08lx, %uMiB, %d-bit\n", 124 phys, (unsigned)(subdev->mtd->size >> 20), 125 subdev->map.bankwidth * 8); 126 127 return 0; 128 129 err: 130 sa1100_destroy_subdev(subdev); 131 out: 132 return ret; 133 } 134 135 static void sa1100_destroy(struct sa_info *info, struct flash_platform_data *plat) 136 { 137 int i; 138 139 if (info->mtd) { 140 mtd_device_unregister(info->mtd); 141 if (info->mtd != info->subdev[0].mtd) 142 mtd_concat_destroy(info->mtd); 143 } 144 145 for (i = info->num_subdev - 1; i >= 0; i--) 146 sa1100_destroy_subdev(&info->subdev[i]); 147 kfree(info); 148 149 if (plat->exit) 150 plat->exit(); 151 } 152 153 static struct sa_info *sa1100_setup_mtd(struct platform_device *pdev, 154 struct flash_platform_data *plat) 155 { 156 struct sa_info *info; 157 int nr, size, i, ret = 0; 158 159 /* 160 * Count number of devices. 161 */ 162 for (nr = 0; ; nr++) 163 if (!platform_get_resource(pdev, IORESOURCE_MEM, nr)) 164 break; 165 166 if (nr == 0) { 167 ret = -ENODEV; 168 goto out; 169 } 170 171 size = sizeof(struct sa_info) + sizeof(struct sa_subdev_info) * nr; 172 173 /* 174 * Allocate the map_info structs in one go. 175 */ 176 info = kzalloc(size, GFP_KERNEL); 177 if (!info) { 178 ret = -ENOMEM; 179 goto out; 180 } 181 182 if (plat->init) { 183 ret = plat->init(); 184 if (ret) 185 goto err; 186 } 187 188 /* 189 * Claim and then map the memory regions. 190 */ 191 for (i = 0; i < nr; i++) { 192 struct sa_subdev_info *subdev = &info->subdev[i]; 193 struct resource *res; 194 195 res = platform_get_resource(pdev, IORESOURCE_MEM, i); 196 if (!res) 197 break; 198 199 subdev->map.name = subdev->name; 200 sprintf(subdev->name, "%s-%d", plat->name, i); 201 subdev->plat = plat; 202 203 ret = sa1100_probe_subdev(subdev, res); 204 if (ret) 205 break; 206 } 207 208 info->num_subdev = i; 209 210 /* 211 * ENXIO is special. It means we didn't find a chip when we probed. 212 */ 213 if (ret != 0 && !(ret == -ENXIO && info->num_subdev > 0)) 214 goto err; 215 216 /* 217 * If we found one device, don't bother with concat support. If 218 * we found multiple devices, use concat if we have it available, 219 * otherwise fail. Either way, it'll be called "sa1100". 220 */ 221 if (info->num_subdev == 1) { 222 strcpy(info->subdev[0].name, plat->name); 223 info->mtd = info->subdev[0].mtd; 224 ret = 0; 225 } else if (info->num_subdev > 1) { 226 struct mtd_info **cdev; 227 228 cdev = kmalloc_array(nr, sizeof(*cdev), GFP_KERNEL); 229 if (!cdev) { 230 ret = -ENOMEM; 231 goto err; 232 } 233 234 /* 235 * We detected multiple devices. Concatenate them together. 236 */ 237 for (i = 0; i < info->num_subdev; i++) 238 cdev[i] = info->subdev[i].mtd; 239 240 info->mtd = mtd_concat_create(cdev, info->num_subdev, 241 plat->name); 242 kfree(cdev); 243 if (info->mtd == NULL) { 244 ret = -ENXIO; 245 goto err; 246 } 247 } 248 info->mtd->dev.parent = &pdev->dev; 249 250 if (ret == 0) 251 return info; 252 253 err: 254 sa1100_destroy(info, plat); 255 out: 256 return ERR_PTR(ret); 257 } 258 259 static const char * const part_probes[] = { "cmdlinepart", "RedBoot", NULL }; 260 261 static int sa1100_mtd_probe(struct platform_device *pdev) 262 { 263 struct flash_platform_data *plat = dev_get_platdata(&pdev->dev); 264 struct sa_info *info; 265 int err; 266 267 if (!plat) 268 return -ENODEV; 269 270 info = sa1100_setup_mtd(pdev, plat); 271 if (IS_ERR(info)) { 272 err = PTR_ERR(info); 273 goto out; 274 } 275 276 /* 277 * Partition selection stuff. 278 */ 279 mtd_device_parse_register(info->mtd, part_probes, NULL, plat->parts, 280 plat->nr_parts); 281 282 platform_set_drvdata(pdev, info); 283 err = 0; 284 285 out: 286 return err; 287 } 288 289 static int sa1100_mtd_remove(struct platform_device *pdev) 290 { 291 struct sa_info *info = platform_get_drvdata(pdev); 292 struct flash_platform_data *plat = dev_get_platdata(&pdev->dev); 293 294 sa1100_destroy(info, plat); 295 296 return 0; 297 } 298 299 static struct platform_driver sa1100_mtd_driver = { 300 .probe = sa1100_mtd_probe, 301 .remove = sa1100_mtd_remove, 302 .driver = { 303 .name = "sa1100-mtd", 304 }, 305 }; 306 307 module_platform_driver(sa1100_mtd_driver); 308 309 MODULE_AUTHOR("Nicolas Pitre"); 310 MODULE_DESCRIPTION("SA1100 CFI map driver"); 311 MODULE_LICENSE("GPL"); 312 MODULE_ALIAS("platform:sa1100-mtd"); 313