1 /* 2 * Copyright (c) 2001 Maciej W. Rozycki 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation; either version 7 * 2 of the License, or (at your option) any later version. 8 * 9 * $Id: ms02-nv.c,v 1.11 2005/11/14 13:41:47 macro Exp $ 10 */ 11 12 #include <linux/init.h> 13 #include <linux/ioport.h> 14 #include <linux/kernel.h> 15 #include <linux/module.h> 16 #include <linux/mtd/mtd.h> 17 #include <linux/slab.h> 18 #include <linux/types.h> 19 20 #include <asm/addrspace.h> 21 #include <asm/bootinfo.h> 22 #include <asm/dec/ioasic_addrs.h> 23 #include <asm/dec/kn02.h> 24 #include <asm/dec/kn03.h> 25 #include <asm/io.h> 26 #include <asm/paccess.h> 27 28 #include "ms02-nv.h" 29 30 31 static char version[] __initdata = 32 "ms02-nv.c: v.1.0.0 13 Aug 2001 Maciej W. Rozycki.\n"; 33 34 MODULE_AUTHOR("Maciej W. Rozycki <macro@linux-mips.org>"); 35 MODULE_DESCRIPTION("DEC MS02-NV NVRAM module driver"); 36 MODULE_LICENSE("GPL"); 37 38 39 /* 40 * Addresses we probe for an MS02-NV at. Modules may be located 41 * at any 8MiB boundary within a 0MiB up to 112MiB range or at any 32MiB 42 * boundary within a 0MiB up to 448MiB range. We don't support a module 43 * at 0MiB, though. 44 */ 45 static ulong ms02nv_addrs[] __initdata = { 46 0x07000000, 0x06800000, 0x06000000, 0x05800000, 0x05000000, 47 0x04800000, 0x04000000, 0x03800000, 0x03000000, 0x02800000, 48 0x02000000, 0x01800000, 0x01000000, 0x00800000 49 }; 50 51 static const char ms02nv_name[] = "DEC MS02-NV NVRAM"; 52 static const char ms02nv_res_diag_ram[] = "Diagnostic RAM"; 53 static const char ms02nv_res_user_ram[] = "General-purpose RAM"; 54 static const char ms02nv_res_csr[] = "Control and status register"; 55 56 static struct mtd_info *root_ms02nv_mtd; 57 58 59 static int ms02nv_read(struct mtd_info *mtd, loff_t from, 60 size_t len, size_t *retlen, u_char *buf) 61 { 62 struct ms02nv_private *mp = mtd->priv; 63 64 if (from + len > mtd->size) 65 return -EINVAL; 66 67 memcpy(buf, mp->uaddr + from, len); 68 *retlen = len; 69 70 return 0; 71 } 72 73 static int ms02nv_write(struct mtd_info *mtd, loff_t to, 74 size_t len, size_t *retlen, const u_char *buf) 75 { 76 struct ms02nv_private *mp = mtd->priv; 77 78 if (to + len > mtd->size) 79 return -EINVAL; 80 81 memcpy(mp->uaddr + to, buf, len); 82 *retlen = len; 83 84 return 0; 85 } 86 87 88 static inline uint ms02nv_probe_one(ulong addr) 89 { 90 ms02nv_uint *ms02nv_diagp; 91 ms02nv_uint *ms02nv_magicp; 92 uint ms02nv_diag; 93 uint ms02nv_magic; 94 size_t size; 95 96 int err; 97 98 /* 99 * The firmware writes MS02NV_ID at MS02NV_MAGIC and also 100 * a diagnostic status at MS02NV_DIAG. 101 */ 102 ms02nv_diagp = (ms02nv_uint *)(CKSEG1ADDR(addr + MS02NV_DIAG)); 103 ms02nv_magicp = (ms02nv_uint *)(CKSEG1ADDR(addr + MS02NV_MAGIC)); 104 err = get_dbe(ms02nv_magic, ms02nv_magicp); 105 if (err) 106 return 0; 107 if (ms02nv_magic != MS02NV_ID) 108 return 0; 109 110 ms02nv_diag = *ms02nv_diagp; 111 size = (ms02nv_diag & MS02NV_DIAG_SIZE_MASK) << MS02NV_DIAG_SIZE_SHIFT; 112 if (size > MS02NV_CSR) 113 size = MS02NV_CSR; 114 115 return size; 116 } 117 118 static int __init ms02nv_init_one(ulong addr) 119 { 120 struct mtd_info *mtd; 121 struct ms02nv_private *mp; 122 struct resource *mod_res; 123 struct resource *diag_res; 124 struct resource *user_res; 125 struct resource *csr_res; 126 ulong fixaddr; 127 size_t size, fixsize; 128 129 static int version_printed; 130 131 int ret = -ENODEV; 132 133 /* The module decodes 8MiB of address space. */ 134 mod_res = kzalloc(sizeof(*mod_res), GFP_KERNEL); 135 if (!mod_res) 136 return -ENOMEM; 137 138 mod_res->name = ms02nv_name; 139 mod_res->start = addr; 140 mod_res->end = addr + MS02NV_SLOT_SIZE - 1; 141 mod_res->flags = IORESOURCE_MEM | IORESOURCE_BUSY; 142 if (request_resource(&iomem_resource, mod_res) < 0) 143 goto err_out_mod_res; 144 145 size = ms02nv_probe_one(addr); 146 if (!size) 147 goto err_out_mod_res_rel; 148 149 if (!version_printed) { 150 printk(KERN_INFO "%s", version); 151 version_printed = 1; 152 } 153 154 ret = -ENOMEM; 155 mtd = kzalloc(sizeof(*mtd), GFP_KERNEL); 156 if (!mtd) 157 goto err_out_mod_res_rel; 158 mp = kzalloc(sizeof(*mp), GFP_KERNEL); 159 if (!mp) 160 goto err_out_mtd; 161 162 mtd->priv = mp; 163 mp->resource.module = mod_res; 164 165 /* Firmware's diagnostic NVRAM area. */ 166 diag_res = kzalloc(sizeof(*diag_res), GFP_KERNEL); 167 if (!diag_res) 168 goto err_out_mp; 169 170 diag_res->name = ms02nv_res_diag_ram; 171 diag_res->start = addr; 172 diag_res->end = addr + MS02NV_RAM - 1; 173 diag_res->flags = IORESOURCE_BUSY; 174 request_resource(mod_res, diag_res); 175 176 mp->resource.diag_ram = diag_res; 177 178 /* User-available general-purpose NVRAM area. */ 179 user_res = kzalloc(sizeof(*user_res), GFP_KERNEL); 180 if (!user_res) 181 goto err_out_diag_res; 182 183 user_res->name = ms02nv_res_user_ram; 184 user_res->start = addr + MS02NV_RAM; 185 user_res->end = addr + size - 1; 186 user_res->flags = IORESOURCE_BUSY; 187 request_resource(mod_res, user_res); 188 189 mp->resource.user_ram = user_res; 190 191 /* Control and status register. */ 192 csr_res = kzalloc(sizeof(*csr_res), GFP_KERNEL); 193 if (!csr_res) 194 goto err_out_user_res; 195 196 csr_res->name = ms02nv_res_csr; 197 csr_res->start = addr + MS02NV_CSR; 198 csr_res->end = addr + MS02NV_CSR + 3; 199 csr_res->flags = IORESOURCE_BUSY; 200 request_resource(mod_res, csr_res); 201 202 mp->resource.csr = csr_res; 203 204 mp->addr = phys_to_virt(addr); 205 mp->size = size; 206 207 /* 208 * Hide the firmware's diagnostic area. It may get destroyed 209 * upon a reboot. Take paging into account for mapping support. 210 */ 211 fixaddr = (addr + MS02NV_RAM + PAGE_SIZE - 1) & ~(PAGE_SIZE - 1); 212 fixsize = (size - (fixaddr - addr)) & ~(PAGE_SIZE - 1); 213 mp->uaddr = phys_to_virt(fixaddr); 214 215 mtd->type = MTD_RAM; 216 mtd->flags = MTD_CAP_RAM; 217 mtd->size = fixsize; 218 mtd->name = (char *)ms02nv_name; 219 mtd->owner = THIS_MODULE; 220 mtd->read = ms02nv_read; 221 mtd->write = ms02nv_write; 222 mtd->writesize = 1; 223 224 ret = -EIO; 225 if (add_mtd_device(mtd)) { 226 printk(KERN_ERR 227 "ms02-nv: Unable to register MTD device, aborting!\n"); 228 goto err_out_csr_res; 229 } 230 231 printk(KERN_INFO "mtd%d: %s at 0x%08lx, size %zuMiB.\n", 232 mtd->index, ms02nv_name, addr, size >> 20); 233 234 mp->next = root_ms02nv_mtd; 235 root_ms02nv_mtd = mtd; 236 237 return 0; 238 239 240 err_out_csr_res: 241 release_resource(csr_res); 242 kfree(csr_res); 243 err_out_user_res: 244 release_resource(user_res); 245 kfree(user_res); 246 err_out_diag_res: 247 release_resource(diag_res); 248 kfree(diag_res); 249 err_out_mp: 250 kfree(mp); 251 err_out_mtd: 252 kfree(mtd); 253 err_out_mod_res_rel: 254 release_resource(mod_res); 255 err_out_mod_res: 256 kfree(mod_res); 257 return ret; 258 } 259 260 static void __exit ms02nv_remove_one(void) 261 { 262 struct mtd_info *mtd = root_ms02nv_mtd; 263 struct ms02nv_private *mp = mtd->priv; 264 265 root_ms02nv_mtd = mp->next; 266 267 del_mtd_device(mtd); 268 269 release_resource(mp->resource.csr); 270 kfree(mp->resource.csr); 271 release_resource(mp->resource.user_ram); 272 kfree(mp->resource.user_ram); 273 release_resource(mp->resource.diag_ram); 274 kfree(mp->resource.diag_ram); 275 release_resource(mp->resource.module); 276 kfree(mp->resource.module); 277 kfree(mp); 278 kfree(mtd); 279 } 280 281 282 static int __init ms02nv_init(void) 283 { 284 volatile u32 *csr; 285 uint stride = 0; 286 int count = 0; 287 int i; 288 289 switch (mips_machtype) { 290 case MACH_DS5000_200: 291 csr = (volatile u32 *)CKSEG1ADDR(KN02_SLOT_BASE + KN02_CSR); 292 if (*csr & KN02_CSR_BNK32M) 293 stride = 2; 294 break; 295 case MACH_DS5000_2X0: 296 case MACH_DS5900: 297 csr = (volatile u32 *)CKSEG1ADDR(KN03_SLOT_BASE + IOASIC_MCR); 298 if (*csr & KN03_MCR_BNK32M) 299 stride = 2; 300 break; 301 default: 302 return -ENODEV; 303 break; 304 } 305 306 for (i = 0; i < ARRAY_SIZE(ms02nv_addrs); i++) 307 if (!ms02nv_init_one(ms02nv_addrs[i] << stride)) 308 count++; 309 310 return (count > 0) ? 0 : -ENODEV; 311 } 312 313 static void __exit ms02nv_cleanup(void) 314 { 315 while (root_ms02nv_mtd) 316 ms02nv_remove_one(); 317 } 318 319 320 module_init(ms02nv_init); 321 module_exit(ms02nv_cleanup); 322