sys/dev/powermac_nvram/powermac_nvram.c

   1 /*
   2  * Copyright (c) 2006 Maxim Sobolev <sobomax@FreeBSD.org>
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  16  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  17  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
  18  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  19  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  20  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  22  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
  23  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  24  * POSSIBILITY OF SUCH DAMAGE.
  25  *
  26  * $FreeBSD$
  27  */
  28
  29 #include <sys/param.h>
  30 #include <sys/systm.h>
  31 #include <sys/module.h>
  32 #include <sys/bus.h>
  33 #include <sys/conf.h>
  34 #include <sys/kernel.h>
  35 #include <sys/uio.h>
  36
  37 #include <dev/ofw/openfirm.h>
  38 #include <dev/ofw/ofw_bus.h>
  39
  40 #include <machine/bus.h>
  41 #include <machine/md_var.h>
  42 #include <machine/pio.h>
  43 #include <machine/resource.h>
  44
  45 #include <sys/rman.h>
  46
  47 #include <dev/powermac_nvram/powermac_nvramvar.h>
  48
  49 #include <vm/vm.h>
  50 #include <vm/pmap.h>
  51
  52 /*
  53  * Device interface.
  54  */
  55 static int              powermac_nvram_probe(device_t);
  56 static int              powermac_nvram_attach(device_t);
  57 static int              powermac_nvram_detach(device_t);
  58
  59 /* Helper functions */
  60 static int              powermac_nvram_check(void *data);
  61 static int              chrp_checksum(int sum, uint8_t *, uint8_t *);
  62 static uint32_t         adler_checksum(uint8_t *, int);
  63 static int              erase_bank(device_t, uint8_t *);
  64 static int              write_bank(device_t, uint8_t *, uint8_t *);
  65
  66 /*
  67  * Driver methods.
  68  */
  69 static device_method_t  powermac_nvram_methods[] = {
  70         /* Device interface */
  71         DEVMETHOD(device_probe,         powermac_nvram_probe),
  72         DEVMETHOD(device_attach,        powermac_nvram_attach),
  73         DEVMETHOD(device_detach,        powermac_nvram_detach),
  74
  75         { 0, 0 }
  76 };
  77
  78 static driver_t powermac_nvram_driver = {
  79         "powermac_nvram",
  80         powermac_nvram_methods,
  81         sizeof(struct powermac_nvram_softc)
  82 };
  83
  84 static devclass_t powermac_nvram_devclass;
  85
  86 DRIVER_MODULE(powermac_nvram, nexus, powermac_nvram_driver, powermac_nvram_devclass, 0, 0);
  87
  88 /*
  89  * Cdev methods.
  90  */
  91
  92 #define NVRAM_UNIT(dev)         dev2unit(dev)
  93 #define NVRAM_SOFTC(unit)       ((struct powermac_nvram_softc *) \
  94      devclass_get_softc(powermac_nvram_devclass, unit))
  95
  96 static  d_open_t        powermac_nvram_open;
  97 static  d_close_t       powermac_nvram_close;
  98 static  d_read_t        powermac_nvram_read;
  99 static  d_write_t       powermac_nvram_write;
 100
 101 static struct cdevsw powermac_nvram_cdevsw = {
 102         .d_version =    D_VERSION,
 103         .d_flags =      D_NEEDGIANT,
 104         .d_open =       powermac_nvram_open,
 105         .d_close =      powermac_nvram_close,
 106         .d_read =       powermac_nvram_read,
 107         .d_write =      powermac_nvram_write,
 108         .d_name =       "powermac_nvram",
 109 };
 110
 111 static int
 112 powermac_nvram_probe(device_t dev)
 113 {
 114         const char      *type, *compatible;
 115
 116         type = ofw_bus_get_type(dev);
 117         compatible = ofw_bus_get_compat(dev);
 118
 119         if (type == NULL || compatible == NULL)
 120                 return ENXIO;
 121
 122         if (strcmp(type, "nvram") != 0 || strcmp(compatible, "amd-0137") != 0)
 123                 return ENXIO;
 124
 125         device_set_desc(dev, "Apple NVRAM");
 126         return 0;
 127 }
 128
 129 static int
 130 powermac_nvram_attach(device_t dev)
 131 {
 132         struct powermac_nvram_softc *sc;
 133         phandle_t node;
 134         u_int32_t reg[2];
 135         int gen0, gen1;
 136
 137         node = ofw_bus_get_node(dev);
 138         sc = device_get_softc(dev);
 139
 140         if (OF_getprop(node, "reg", reg, sizeof(reg)) < 8)
 141                 return ENXIO;
 142
 143         sc->sc_dev = dev;
 144         sc->sc_node = node;
 145
 146         sc->sc_bank0 = (vm_offset_t)pmap_mapdev(reg[0], NVRAM_SIZE * 2);
 147         sc->sc_bank1 = sc->sc_bank0 + NVRAM_SIZE;
 148
 149         gen0 = powermac_nvram_check((void *)sc->sc_bank0);
 150         gen1 = powermac_nvram_check((void *)sc->sc_bank1);
 151
 152         if (gen0 == -1 && gen1 == -1) {
 153                 if ((void *)sc->sc_bank0 != NULL)
 154                         pmap_unmapdev(sc->sc_bank0, NVRAM_SIZE * 2);
 155                 device_printf(dev, "both banks appear to be corrupt\n");
 156                 return ENXIO;
 157         }
 158         device_printf(dev, "bank0 generation %d, bank1 generation %d\n",
 159             gen0, gen1);
 160
 161         sc->sc_bank = (gen0 > gen1) ? sc->sc_bank0 : sc->sc_bank1;
 162         bcopy((void *)sc->sc_bank, (void *)sc->sc_data, NVRAM_SIZE);
 163
 164         sc->sc_cdev = make_dev(&powermac_nvram_cdevsw, 0, 0, 0, 0600,
 165             "powermac_nvram");
 166
 167         return 0;
 168 }
 169
 170 static int
 171 powermac_nvram_detach(device_t dev)
 172 {
 173         struct powermac_nvram_softc *sc;
 174
 175         sc = device_get_softc(dev);
 176
 177         if ((void *)sc->sc_bank0 != NULL)
 178                 pmap_unmapdev(sc->sc_bank0, NVRAM_SIZE * 2);
 179
 180         if (sc->sc_cdev != NULL)
 181                 destroy_dev(sc->sc_cdev);
 182
 183         return 0;
 184 }
 185
 186 static int
 187 powermac_nvram_open(struct cdev *dev, int flags, int fmt, struct thread *td)
 188 {
 189         struct powermac_nvram_softc *sc;
 190
 191         sc = NVRAM_SOFTC(NVRAM_UNIT(dev));
 192         if (sc->sc_isopen)
 193                 return EBUSY;
 194         sc->sc_isopen = 1;
 195         sc->sc_rpos = sc->sc_wpos = 0;
 196         return 0;
 197 }
 198
 199 static int
 200 powermac_nvram_close(struct cdev *dev, int fflag, int devtype, struct thread *td)
 201 {
 202         struct powermac_nvram_softc *sc;
 203         struct core99_header *header;
 204         vm_offset_t bank;
 205
 206         sc = NVRAM_SOFTC(NVRAM_UNIT(dev));
 207
 208         if (sc->sc_wpos != sizeof(sc->sc_data)) {
 209                 /* Short write, restore in-memory copy */
 210                 bcopy((void *)sc->sc_bank, (void *)sc->sc_data, NVRAM_SIZE);
 211                 sc->sc_isopen = 0;
 212                 return 0;
 213         }
 214
 215         header = (struct core99_header *)sc->sc_data;
 216
 217         header->generation = ((struct core99_header *)sc->sc_bank)->generation;
 218         header->generation++;
 219         header->chrp_header.signature = CORE99_SIGNATURE;
 220
 221         header->adler_checksum =
 222             adler_checksum((uint8_t *)&(header->generation),
 223             NVRAM_SIZE - offsetof(struct core99_header, generation));
 224         header->chrp_header.chrp_checksum = chrp_checksum(header->chrp_header.signature,
 225             (uint8_t *)&(header->chrp_header.length),
 226             (uint8_t *)&(header->adler_checksum));
 227
 228         bank = (sc->sc_bank == sc->sc_bank0) ? sc->sc_bank1 : sc->sc_bank0;
 229         if (erase_bank(sc->sc_dev, (uint8_t *)bank) != 0 ||
 230             write_bank(sc->sc_dev, (uint8_t *)bank, sc->sc_data) != 0) {
 231                 sc->sc_isopen = 0;
 232                 return ENOSPC;
 233         }
 234         sc->sc_bank = bank;
 235         sc->sc_isopen = 0;
 236         return 0;
 237 }
 238
 239 static int
 240 powermac_nvram_read(struct cdev *dev, struct uio *uio, int ioflag)
 241 {
 242         int rv, amnt, data_available;
 243         struct powermac_nvram_softc *sc;
 244
 245         sc = NVRAM_SOFTC(NVRAM_UNIT(dev));
 246
 247         rv = 0;
 248         while (uio->uio_resid > 0) {
 249                 data_available = sizeof(sc->sc_data) - sc->sc_rpos;
 250                 if (data_available > 0) {
 251                         amnt = MIN(uio->uio_resid, data_available);
 252                         rv = uiomove((void *)(sc->sc_data + sc->sc_rpos),
 253                             amnt, uio);
 254                         if (rv != 0)
 255                                 break;
 256                         sc->sc_rpos += amnt;
 257                 } else {
 258                         break;
 259                 }
 260         }
 261         return rv;
 262 }
 263
 264 static int
 265 powermac_nvram_write(struct cdev *dev, struct uio *uio, int ioflag)
 266 {
 267         int rv, amnt, data_available;
 268         struct powermac_nvram_softc *sc;
 269
 270         sc = NVRAM_SOFTC(NVRAM_UNIT(dev));
 271
 272         if (sc->sc_wpos >= sizeof(sc->sc_data))
 273                 return EINVAL;
 274
 275         rv = 0;
 276         while (uio->uio_resid > 0) {
 277                 data_available = sizeof(sc->sc_data) - sc->sc_wpos;
 278                 if (data_available > 0) {
 279                         amnt = MIN(uio->uio_resid, data_available);
 280                         rv = uiomove((void *)(sc->sc_data + sc->sc_wpos),
 281                             amnt, uio);
 282                         if (rv != 0)
 283                                 break;
 284                         sc->sc_wpos += amnt;
 285                 } else {
 286                         break;
 287                 }
 288         }
 289         return rv;
 290 }
 291
 292 static int
 293 powermac_nvram_check(void *data)
 294 {
 295         struct core99_header *header;
 296
 297         header = (struct core99_header *)data;
 298
 299         if (header->chrp_header.signature != CORE99_SIGNATURE)
 300                 return -1;
 301         if (header->chrp_header.chrp_checksum !=
 302             chrp_checksum(header->chrp_header.signature,
 303             (uint8_t *)&(header->chrp_header.length),
 304             (uint8_t *)&(header->adler_checksum)))
 305                 return -1;
 306         if (header->adler_checksum !=
 307             adler_checksum((uint8_t *)&(header->generation),
 308             NVRAM_SIZE - offsetof(struct core99_header, generation)))
 309                 return -1;
 310         return header->generation;
 311 }
 312
 313 static int
 314 chrp_checksum(int sum, uint8_t *data, uint8_t *end)
 315 {
 316
 317         for (; data < end; data++)
 318                 sum += data[0];
 319         while (sum > 0xff)
 320                 sum = (sum & 0xff) + (sum >> 8);
 321         return sum;
 322 }
 323
 324 static uint32_t
 325 adler_checksum(uint8_t *data, int len)
 326 {
 327         uint32_t low, high;
 328         int i;
 329
 330         low = 1;
 331         high = 0;
 332         for (i = 0; i < len; i++) {
 333                 if ((i % 5000) == 0) {
 334                         high %= 65521UL;
 335                         high %= 65521UL;
 336                 }
 337                 low += data[i];
 338                 high += low;
 339         }
 340         low %= 65521UL;
 341         high %= 65521UL;
 342
 343         return (high << 16) | low;
 344 }
 345
 346 #define OUTB_DELAY(a, v)        outb(a, v); DELAY(1);
 347
 348 static int
 349 wait_operation_complete(uint8_t *bank)
 350 {
 351         int i;
 352
 353         for (i = 1000000; i != 0; i--)
 354                 if ((inb(bank) ^ inb(bank)) == 0)
 355                         return 0;
 356         return -1;
 357 }
 358
 359 static int
 360 erase_bank(device_t dev, uint8_t *bank)
 361 {
 362         unsigned int i;
 363
 364         /* Unlock 1 */
 365         OUTB_DELAY(bank + 0x555, 0xaa);
 366         /* Unlock 2 */
 367         OUTB_DELAY(bank + 0x2aa, 0x55);
 368
 369         /* Sector-Erase */
 370         OUTB_DELAY(bank + 0x555, 0x80);
 371         OUTB_DELAY(bank + 0x555, 0xaa);
 372         OUTB_DELAY(bank + 0x2aa, 0x55);
 373         OUTB_DELAY(bank, 0x30);
 374
 375         if (wait_operation_complete(bank) != 0) {
 376                 device_printf(dev, "flash erase timeout\n");
 377                 return -1;
 378         }
 379
 380         /* Reset */
 381         OUTB_DELAY(bank, 0xf0);
 382
 383         for (i = 0; i < NVRAM_SIZE; i++) {
 384                 if (bank[i] != 0xff) {
 385                         device_printf(dev, "flash erase has failed\n");
 386                         return -1;
 387                 }
 388         }
 389         return 0;
 390 }
 391
 392 static int
 393 write_bank(device_t dev, uint8_t *bank, uint8_t *data)
 394 {
 395         unsigned int i;
 396
 397         for (i = 0; i < NVRAM_SIZE; i++) {
 398                 /* Unlock 1 */
 399                 OUTB_DELAY(bank + 0x555, 0xaa);
 400                 /* Unlock 2 */
 401                 OUTB_DELAY(bank + 0x2aa, 0x55);
 402
 403                 /* Write single word */
 404                 OUTB_DELAY(bank + 0x555, 0xa0);
 405                 OUTB_DELAY(bank + i, data[i]);
 406                 if (wait_operation_complete(bank) != 0) {
 407                         device_printf(dev, "flash write timeout\n");
 408                         return -1;
 409                 }
 410         }
 411
 412         /* Reset */
 413         OUTB_DELAY(bank, 0xf0);
 414
 415         for (i = 0; i < NVRAM_SIZE; i++) {
 416                 if (bank[i] != data[i]) {
 417                         device_printf(dev, "flash write has failed\n");
 418                         return -1;
 419                 }
 420         }
 421         return 0;
 422 }