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 1.8 2005/01/05 18:05:12 dwmw2 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 *)(KSEG1ADDR(addr + MS02NV_DIAG)); 103 ms02nv_magicp = (ms02nv_uint *)(KSEG1ADDR(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 = kmalloc(sizeof(*mod_res), GFP_KERNEL); 135 if (!mod_res) 136 return -ENOMEM; 137 138 memset(mod_res, 0, sizeof(*mod_res)); 139 mod_res->name = ms02nv_name; 140 mod_res->start = addr; 141 mod_res->end = addr + MS02NV_SLOT_SIZE - 1; 142 mod_res->flags = IORESOURCE_MEM | IORESOURCE_BUSY; 143 if (request_resource(&iomem_resource, mod_res) < 0) 144 goto err_out_mod_res; 145 146 size = ms02nv_probe_one(addr); 147 if (!size) 148 goto err_out_mod_res_rel; 149 150 if (!version_printed) { 151 printk(KERN_INFO "%s", version); 152 version_printed = 1; 153 } 154 155 ret = -ENOMEM; 156 mtd = kmalloc(sizeof(*mtd), GFP_KERNEL); 157 if (!mtd) 158 goto err_out_mod_res_rel; 159 memset(mtd, 0, sizeof(*mtd)); 160 mp = kmalloc(sizeof(*mp), GFP_KERNEL); 161 if (!mp) 162 goto err_out_mtd; 163 memset(mp, 0, sizeof(*mp)); 164 165 mtd->priv = mp; 166 mp->resource.module = mod_res; 167 168 /* Firmware's diagnostic NVRAM area. */ 169 diag_res = kmalloc(sizeof(*diag_res), GFP_KERNEL); 170 if (!diag_res) 171 goto err_out_mp; 172 173 memset(diag_res, 0, sizeof(*diag_res)); 174 diag_res->name = ms02nv_res_diag_ram; 175 diag_res->start = addr; 176 diag_res->end = addr + MS02NV_RAM - 1; 177 diag_res->flags = IORESOURCE_BUSY; 178 request_resource(mod_res, diag_res); 179 180 mp->resource.diag_ram = diag_res; 181 182 /* User-available general-purpose NVRAM area. */ 183 user_res = kmalloc(sizeof(*user_res), GFP_KERNEL); 184 if (!user_res) 185 goto err_out_diag_res; 186 187 memset(user_res, 0, sizeof(*user_res)); 188 user_res->name = ms02nv_res_user_ram; 189 user_res->start = addr + MS02NV_RAM; 190 user_res->end = addr + size - 1; 191 user_res->flags = IORESOURCE_BUSY; 192 request_resource(mod_res, user_res); 193 194 mp->resource.user_ram = user_res; 195 196 /* Control and status register. */ 197 csr_res = kmalloc(sizeof(*csr_res), GFP_KERNEL); 198 if (!csr_res) 199 goto err_out_user_res; 200 201 memset(csr_res, 0, sizeof(*csr_res)); 202 csr_res->name = ms02nv_res_csr; 203 csr_res->start = addr + MS02NV_CSR; 204 csr_res->end = addr + MS02NV_CSR + 3; 205 csr_res->flags = IORESOURCE_BUSY; 206 request_resource(mod_res, csr_res); 207 208 mp->resource.csr = csr_res; 209 210 mp->addr = phys_to_virt(addr); 211 mp->size = size; 212 213 /* 214 * Hide the firmware's diagnostic area. It may get destroyed 215 * upon a reboot. Take paging into account for mapping support. 216 */ 217 fixaddr = (addr + MS02NV_RAM + PAGE_SIZE - 1) & ~(PAGE_SIZE - 1); 218 fixsize = (size - (fixaddr - addr)) & ~(PAGE_SIZE - 1); 219 mp->uaddr = phys_to_virt(fixaddr); 220 221 mtd->type = MTD_RAM; 222 mtd->flags = MTD_CAP_RAM | MTD_XIP; 223 mtd->size = fixsize; 224 mtd->name = (char *)ms02nv_name; 225 mtd->owner = THIS_MODULE; 226 mtd->read = ms02nv_read; 227 mtd->write = ms02nv_write; 228 229 ret = -EIO; 230 if (add_mtd_device(mtd)) { 231 printk(KERN_ERR 232 "ms02-nv: Unable to register MTD device, aborting!\n"); 233 goto err_out_csr_res; 234 } 235 236 printk(KERN_INFO "mtd%d: %s at 0x%08lx, size %uMiB.\n", 237 mtd->index, ms02nv_name, addr, size >> 20); 238 239 mp->next = root_ms02nv_mtd; 240 root_ms02nv_mtd = mtd; 241 242 return 0; 243 244 245 err_out_csr_res: 246 release_resource(csr_res); 247 kfree(csr_res); 248 err_out_user_res: 249 release_resource(user_res); 250 kfree(user_res); 251 err_out_diag_res: 252 release_resource(diag_res); 253 kfree(diag_res); 254 err_out_mp: 255 kfree(mp); 256 err_out_mtd: 257 kfree(mtd); 258 err_out_mod_res_rel: 259 release_resource(mod_res); 260 err_out_mod_res: 261 kfree(mod_res); 262 return ret; 263 } 264 265 static void __exit ms02nv_remove_one(void) 266 { 267 struct mtd_info *mtd = root_ms02nv_mtd; 268 struct ms02nv_private *mp = mtd->priv; 269 270 root_ms02nv_mtd = mp->next; 271 272 del_mtd_device(mtd); 273 274 release_resource(mp->resource.csr); 275 kfree(mp->resource.csr); 276 release_resource(mp->resource.user_ram); 277 kfree(mp->resource.user_ram); 278 release_resource(mp->resource.diag_ram); 279 kfree(mp->resource.diag_ram); 280 release_resource(mp->resource.module); 281 kfree(mp->resource.module); 282 kfree(mp); 283 kfree(mtd); 284 } 285 286 287 static int __init ms02nv_init(void) 288 { 289 volatile u32 *csr; 290 uint stride = 0; 291 int count = 0; 292 int i; 293 294 switch (mips_machtype) { 295 case MACH_DS5000_200: 296 csr = (volatile u32 *)KN02_CSR_BASE; 297 if (*csr & KN02_CSR_BNK32M) 298 stride = 2; 299 break; 300 case MACH_DS5000_2X0: 301 case MACH_DS5900: 302 csr = (volatile u32 *)KN03_MCR_BASE; 303 if (*csr & KN03_MCR_BNK32M) 304 stride = 2; 305 break; 306 default: 307 return -ENODEV; 308 break; 309 } 310 311 for (i = 0; i < (sizeof(ms02nv_addrs) / sizeof(*ms02nv_addrs)); i++) 312 if (!ms02nv_init_one(ms02nv_addrs[i] << stride)) 313 count++; 314 315 return (count > 0) ? 0 : -ENODEV; 316 } 317 318 static void __exit ms02nv_cleanup(void) 319 { 320 while (root_ms02nv_mtd) 321 ms02nv_remove_one(); 322 } 323 324 325 module_init(ms02nv_init); 326 module_exit(ms02nv_cleanup); 327