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 static  d_open_t        powermac_nvram_open;
  93 static  d_close_t       powermac_nvram_close;
  94 static  d_read_t        powermac_nvram_read;
  95 static  d_write_t       powermac_nvram_write;
  96
  97 static struct cdevsw powermac_nvram_cdevsw = {
  98         .d_version =    D_VERSION,
  99         .d_flags =      D_NEEDGIANT,
 100         .d_open =       powermac_nvram_open,
 101         .d_close =      powermac_nvram_close,
 102         .d_read =       powermac_nvram_read,
 103         .d_write =      powermac_nvram_write,
 104         .d_name =       "powermac_nvram",
 105 };
 106
 107 static int
 108 powermac_nvram_probe(device_t dev)
 109 {
 110         const char      *type, *compatible;
 111
 112         type = ofw_bus_get_type(dev);
 113         compatible = ofw_bus_get_compat(dev);
 114
 115         if (type == NULL || compatible == NULL)
 116                 return ENXIO;
 117
 118         if (strcmp(type, "nvram") != 0 || strcmp(compatible, "amd-0137") != 0)
 119                 return ENXIO;
 120
 121         device_set_desc(dev, "Apple NVRAM");
 122         return 0;
 123 }
 124
 125 static int
 126 powermac_nvram_attach(device_t dev)
 127 {
 128         struct powermac_nvram_softc *sc;
 129         phandle_t node;
 130         u_int32_t reg[3];
 131         int gen0, gen1, i;
 132
 133         node = ofw_bus_get_node(dev);
 134         sc = device_get_softc(dev);
 135
 136         if ((i = OF_getprop(node, "reg", reg, sizeof(reg))) < 8)
 137                 return ENXIO;
 138
 139         sc->sc_dev = dev;
 140         sc->sc_node = node;
 141
 142         /*
 143          * Find which byte of reg corresponds to the 32-bit physical address.
 144          * We should probably read #address-cells from /chosen instead.
 145          */
 146         i = (i/4) - 2;
 147
 148         sc->sc_bank0 = (vm_offset_t)pmap_mapdev(reg[i], NVRAM_SIZE * 2);
 149         sc->sc_bank1 = sc->sc_bank0 + NVRAM_SIZE;
 150
 151         gen0 = powermac_nvram_check((void *)sc->sc_bank0);
 152         gen1 = powermac_nvram_check((void *)sc->sc_bank1);
 153
 154         if (gen0 == -1 && gen1 == -1) {
 155                 if ((void *)sc->sc_bank0 != NULL)
 156                         pmap_unmapdev(sc->sc_bank0, NVRAM_SIZE * 2);
 157                 device_printf(dev, "both banks appear to be corrupt\n");
 158                 return ENXIO;
 159         }
 160         device_printf(dev, "bank0 generation %d, bank1 generation %d\n",
 161             gen0, gen1);
 162
 163         sc->sc_bank = (gen0 > gen1) ? sc->sc_bank0 : sc->sc_bank1;
 164         bcopy((void *)sc->sc_bank, (void *)sc->sc_data, NVRAM_SIZE);
 165
 166         sc->sc_cdev = make_dev(&powermac_nvram_cdevsw, 0, 0, 0, 0600,
 167             "powermac_nvram");
 168         sc->sc_cdev->si_drv1 = sc;
 169
 170         return 0;
 171 }
 172
 173 static int
 174 powermac_nvram_detach(device_t dev)
 175 {
 176         struct powermac_nvram_softc *sc;
 177
 178         sc = device_get_softc(dev);
 179
 180         if ((void *)sc->sc_bank0 != NULL)
 181                 pmap_unmapdev(sc->sc_bank0, NVRAM_SIZE * 2);
 182
 183         if (sc->sc_cdev != NULL)
 184                 destroy_dev(sc->sc_cdev);
 185
 186         return 0;
 187 }
 188
 189 static int
 190 powermac_nvram_open(struct cdev *dev, int flags, int fmt, struct thread *td)
 191 {
 192         struct powermac_nvram_softc *sc = dev->si_drv1;
 193
 194         if (sc->sc_isopen)
 195                 return EBUSY;
 196         sc->sc_isopen = 1;
 197         sc->sc_rpos = sc->sc_wpos = 0;
 198         return 0;
 199 }
 200
 201 static int
 202 powermac_nvram_close(struct cdev *dev, int fflag, int devtype, struct thread *td)
 203 {
 204         struct powermac_nvram_softc *sc = dev->si_drv1;
 205         struct core99_header *header;
 206         vm_offset_t bank;
 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 = dev->si_drv1;
 244
 245         rv = 0;
 246         while (uio->uio_resid > 0) {
 247                 data_available = sizeof(sc->sc_data) - sc->sc_rpos;
 248                 if (data_available > 0) {
 249                         amnt = MIN(uio->uio_resid, data_available);
 250                         rv = uiomove((void *)(sc->sc_data + sc->sc_rpos),
 251                             amnt, uio);
 252                         if (rv != 0)
 253                                 break;
 254                         sc->sc_rpos += amnt;
 255                 } else {
 256                         break;
 257                 }
 258         }
 259         return rv;
 260 }
 261
 262 static int
 263 powermac_nvram_write(struct cdev *dev, struct uio *uio, int ioflag)
 264 {
 265         int rv, amnt, data_available;
 266         struct powermac_nvram_softc *sc = dev->si_drv1;
 267
 268         if (sc->sc_wpos >= sizeof(sc->sc_data))
 269                 return EINVAL;
 270
 271         rv = 0;
 272         while (uio->uio_resid > 0) {
 273                 data_available = sizeof(sc->sc_data) - sc->sc_wpos;
 274                 if (data_available > 0) {
 275                         amnt = MIN(uio->uio_resid, data_available);
 276                         rv = uiomove((void *)(sc->sc_data + sc->sc_wpos),
 277                             amnt, uio);
 278                         if (rv != 0)
 279                                 break;
 280                         sc->sc_wpos += amnt;
 281                 } else {
 282                         break;
 283                 }
 284         }
 285         return rv;
 286 }
 287
 288 static int
 289 powermac_nvram_check(void *data)
 290 {
 291         struct core99_header *header;
 292
 293         header = (struct core99_header *)data;
 294
 295         if (header->chrp_header.signature != CORE99_SIGNATURE)
 296                 return -1;
 297         if (header->chrp_header.chrp_checksum !=
 298             chrp_checksum(header->chrp_header.signature,
 299             (uint8_t *)&(header->chrp_header.length),
 300             (uint8_t *)&(header->adler_checksum)))
 301                 return -1;
 302         if (header->adler_checksum !=
 303             adler_checksum((uint8_t *)&(header->generation),
 304             NVRAM_SIZE - offsetof(struct core99_header, generation)))
 305                 return -1;
 306         return header->generation;
 307 }
 308
 309 static int
 310 chrp_checksum(int sum, uint8_t *data, uint8_t *end)
 311 {
 312
 313         for (; data < end; data++)
 314                 sum += data[0];
 315         while (sum > 0xff)
 316                 sum = (sum & 0xff) + (sum >> 8);
 317         return sum;
 318 }
 319
 320 static uint32_t
 321 adler_checksum(uint8_t *data, int len)
 322 {
 323         uint32_t low, high;
 324         int i;
 325
 326         low = 1;
 327         high = 0;
 328         for (i = 0; i < len; i++) {
 329                 if ((i % 5000) == 0) {
 330                         high %= 65521UL;
 331                         high %= 65521UL;
 332                 }
 333                 low += data[i];
 334                 high += low;
 335         }
 336         low %= 65521UL;
 337         high %= 65521UL;
 338
 339         return (high << 16) | low;
 340 }
 341
 342 #define OUTB_DELAY(a, v)        outb(a, v); DELAY(1);
 343
 344 static int
 345 wait_operation_complete(uint8_t *bank)
 346 {
 347         int i;
 348
 349         for (i = 1000000; i != 0; i--)
 350                 if ((inb(bank) ^ inb(bank)) == 0)
 351                         return 0;
 352         return -1;
 353 }
 354
 355 static int
 356 erase_bank(device_t dev, uint8_t *bank)
 357 {
 358         unsigned int i;
 359
 360         /* Unlock 1 */
 361         OUTB_DELAY(bank + 0x555, 0xaa);
 362         /* Unlock 2 */
 363         OUTB_DELAY(bank + 0x2aa, 0x55);
 364
 365         /* Sector-Erase */
 366         OUTB_DELAY(bank + 0x555, 0x80);
 367         OUTB_DELAY(bank + 0x555, 0xaa);
 368         OUTB_DELAY(bank + 0x2aa, 0x55);
 369         OUTB_DELAY(bank, 0x30);
 370
 371         if (wait_operation_complete(bank) != 0) {
 372                 device_printf(dev, "flash erase timeout\n");
 373                 return -1;
 374         }
 375
 376         /* Reset */
 377         OUTB_DELAY(bank, 0xf0);
 378
 379         for (i = 0; i < NVRAM_SIZE; i++) {
 380                 if (bank[i] != 0xff) {
 381                         device_printf(dev, "flash erase has failed\n");
 382                         return -1;
 383                 }
 384         }
 385         return 0;
 386 }
 387
 388 static int
 389 write_bank(device_t dev, uint8_t *bank, uint8_t *data)
 390 {
 391         unsigned int i;
 392
 393         for (i = 0; i < NVRAM_SIZE; i++) {
 394                 /* Unlock 1 */
 395                 OUTB_DELAY(bank + 0x555, 0xaa);
 396                 /* Unlock 2 */
 397                 OUTB_DELAY(bank + 0x2aa, 0x55);
 398
 399                 /* Write single word */
 400                 OUTB_DELAY(bank + 0x555, 0xa0);
 401                 OUTB_DELAY(bank + i, data[i]);
 402                 if (wait_operation_complete(bank) != 0) {
 403                         device_printf(dev, "flash write timeout\n");
 404                         return -1;
 405                 }
 406         }
 407
 408         /* Reset */
 409         OUTB_DELAY(bank, 0xf0);
 410
 411         for (i = 0; i < NVRAM_SIZE; i++) {
 412                 if (bank[i] != data[i]) {
 413                         device_printf(dev, "flash write has failed\n");
 414                         return -1;
 415                 }
 416         }
 417         return 0;
 418 }