drivers/net/e1000_spi.c

   1 #include "e1000.h"
   2 #include <linux/compiler.h>
   3
   4 /*-----------------------------------------------------------------------
   5  * SPI transfer
   6  *
   7  * This writes "bitlen" bits out the SPI MOSI port and simultaneously clocks
   8  * "bitlen" bits in the SPI MISO port.  That's just the way SPI works.
   9  *
  10  * The source of the outgoing bits is the "dout" parameter and the
  11  * destination of the input bits is the "din" parameter.  Note that "dout"
  12  * and "din" can point to the same memory location, in which case the
  13  * input data overwrites the output data (since both are buffered by
  14  * temporary variables, this is OK).
  15  *
  16  * This may be interrupted with Ctrl-C if "intr" is true, otherwise it will
  17  * never return an error.
  18  */
  19 static int e1000_spi_xfer(struct e1000_hw *hw, unsigned int bitlen,
  20                 const void *dout_mem, void *din_mem, bool intr)
  21 {
  22         const uint8_t *dout = dout_mem;
  23         uint8_t *din = din_mem;
  24
  25         uint8_t mask = 0;
  26         uint32_t eecd;
  27         unsigned long i;
  28
  29         /* Pre-read the control register */
  30         eecd = E1000_READ_REG(hw, EECD);
  31
  32         /* Iterate over each bit */
  33         for (i = 0, mask = 0x80; i < bitlen; i++, mask = (mask >> 1)?:0x80) {
  34                 /* Check for interrupt */
  35                 if (intr && ctrlc())
  36                         return -1;
  37
  38                 /* Determine the output bit */
  39                 if (dout && dout[i >> 3] & mask)
  40                         eecd |=  E1000_EECD_DI;
  41                 else
  42                         eecd &= ~E1000_EECD_DI;
  43
  44                 /* Write the output bit and wait 50us */
  45                 E1000_WRITE_REG(hw, EECD, eecd);
  46                 E1000_WRITE_FLUSH(hw);
  47                 udelay(50);
  48
  49                 /* Poke the clock (waits 50us) */
  50                 e1000_raise_ee_clk(hw, &eecd);
  51
  52                 /* Now read the input bit */
  53                 eecd = E1000_READ_REG(hw, EECD);
  54                 if (din) {
  55                         if (eecd & E1000_EECD_DO)
  56                                 din[i >> 3] |=  mask;
  57                         else
  58                                 din[i >> 3] &= ~mask;
  59                 }
  60
  61                 /* Poke the clock again (waits 50us) */
  62                 e1000_lower_ee_clk(hw, &eecd);
  63         }
  64
  65         /* Now clear any remaining bits of the input */
  66         if (din && (i & 7))
  67                 din[i >> 3] &= ~((mask << 1) - 1);
  68
  69         return 0;
  70 }
  71
  72 #ifdef CONFIG_E1000_SPI_GENERIC
  73 static inline struct e1000_hw *e1000_hw_from_spi(struct spi_slave *spi)
  74 {
  75         return container_of(spi, struct e1000_hw, spi);
  76 }
  77
  78 /* Not sure why all of these are necessary */
  79 void spi_init_r(void) { /* Nothing to do */ }
  80 void spi_init_f(void) { /* Nothing to do */ }
  81 void spi_init(void)   { /* Nothing to do */ }
  82
  83 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
  84                 unsigned int max_hz, unsigned int mode)
  85 {
  86         /* Find the right PCI device */
  87         struct e1000_hw *hw = e1000_find_card(bus);
  88         if (!hw) {
  89                 printf("ERROR: No such e1000 device: e1000#%u\n", bus);
  90                 return NULL;
  91         }
  92
  93         /* Make sure it has an SPI chip */
  94         if (hw->eeprom.type != e1000_eeprom_spi) {
  95                 E1000_ERR(hw->nic, "No attached SPI EEPROM found!\n");
  96                 return NULL;
  97         }
  98
  99         /* Argument sanity checks */
 100         if (cs != 0) {
 101                 E1000_ERR(hw->nic, "No such SPI chip: %u\n", cs);
 102                 return NULL;
 103         }
 104         if (mode != SPI_MODE_0) {
 105                 E1000_ERR(hw->nic, "Only SPI MODE-0 is supported!\n");
 106                 return NULL;
 107         }
 108
 109         /* TODO: Use max_hz somehow */
 110         E1000_DBG(hw->nic, "EEPROM SPI access requested\n");
 111         return &hw->spi;
 112 }
 113
 114 void spi_free_slave(struct spi_slave *spi)
 115 {
 116         __maybe_unused struct e1000_hw *hw = e1000_hw_from_spi(spi);
 117         E1000_DBG(hw->nic, "EEPROM SPI access released\n");
 118 }
 119
 120 int spi_claim_bus(struct spi_slave *spi)
 121 {
 122         struct e1000_hw *hw = e1000_hw_from_spi(spi);
 123
 124         if (e1000_acquire_eeprom(hw)) {
 125                 E1000_ERR(hw->nic, "EEPROM SPI cannot be acquired!\n");
 126                 return -1;
 127         }
 128
 129         return 0;
 130 }
 131
 132 void spi_release_bus(struct spi_slave *spi)
 133 {
 134         struct e1000_hw *hw = e1000_hw_from_spi(spi);
 135         e1000_release_eeprom(hw);
 136 }
 137
 138 /* Skinny wrapper around e1000_spi_xfer */
 139 int spi_xfer(struct spi_slave *spi, unsigned int bitlen,
 140                 const void *dout_mem, void *din_mem, unsigned long flags)
 141 {
 142         struct e1000_hw *hw = e1000_hw_from_spi(spi);
 143         int ret;
 144
 145         if (flags & SPI_XFER_BEGIN)
 146                 e1000_standby_eeprom(hw);
 147
 148         ret = e1000_spi_xfer(hw, bitlen, dout_mem, din_mem, true);
 149
 150         if (flags & SPI_XFER_END)
 151                 e1000_standby_eeprom(hw);
 152
 153         return ret;
 154 }
 155
 156 #endif /* not CONFIG_E1000_SPI_GENERIC */
 157
 158 #ifdef CONFIG_CMD_E1000
 159
 160 /* The EEPROM opcodes */
 161 #define SPI_EEPROM_ENABLE_WR    0x06
 162 #define SPI_EEPROM_DISABLE_WR   0x04
 163 #define SPI_EEPROM_WRITE_STATUS 0x01
 164 #define SPI_EEPROM_READ_STATUS  0x05
 165 #define SPI_EEPROM_WRITE_PAGE   0x02
 166 #define SPI_EEPROM_READ_PAGE    0x03
 167
 168 /* The EEPROM status bits */
 169 #define SPI_EEPROM_STATUS_BUSY  0x01
 170 #define SPI_EEPROM_STATUS_WREN  0x02
 171
 172 static int e1000_spi_eeprom_enable_wr(struct e1000_hw *hw, bool intr)
 173 {
 174         u8 op[] = { SPI_EEPROM_ENABLE_WR };
 175         e1000_standby_eeprom(hw);
 176         return e1000_spi_xfer(hw, 8*sizeof(op), op, NULL, intr);
 177 }
 178
 179 /*
 180  * These have been tested to perform correctly, but they are not used by any
 181  * of the EEPROM commands at this time.
 182  */
 183 #if 0
 184 static int e1000_spi_eeprom_disable_wr(struct e1000_hw *hw, bool intr)
 185 {
 186         u8 op[] = { SPI_EEPROM_DISABLE_WR };
 187         e1000_standby_eeprom(hw);
 188         return e1000_spi_xfer(hw, 8*sizeof(op), op, NULL, intr);
 189 }
 190
 191 static int e1000_spi_eeprom_write_status(struct e1000_hw *hw,
 192                 u8 status, bool intr)
 193 {
 194         u8 op[] = { SPI_EEPROM_WRITE_STATUS, status };
 195         e1000_standby_eeprom(hw);
 196         return e1000_spi_xfer(hw, 8*sizeof(op), op, NULL, intr);
 197 }
 198 #endif
 199
 200 static int e1000_spi_eeprom_read_status(struct e1000_hw *hw, bool intr)
 201 {
 202         u8 op[] = { SPI_EEPROM_READ_STATUS, 0 };
 203         e1000_standby_eeprom(hw);
 204         if (e1000_spi_xfer(hw, 8*sizeof(op), op, op, intr))
 205                 return -1;
 206         return op[1];
 207 }
 208
 209 static int e1000_spi_eeprom_write_page(struct e1000_hw *hw,
 210                 const void *data, u16 off, u16 len, bool intr)
 211 {
 212         u8 op[] = {
 213                 SPI_EEPROM_WRITE_PAGE,
 214                 (off >> (hw->eeprom.address_bits - 8)) & 0xff, off & 0xff
 215         };
 216
 217         e1000_standby_eeprom(hw);
 218
 219         if (e1000_spi_xfer(hw, 8 + hw->eeprom.address_bits, op, NULL, intr))
 220                 return -1;
 221         if (e1000_spi_xfer(hw, len << 3, data, NULL, intr))
 222                 return -1;
 223
 224         return 0;
 225 }
 226
 227 static int e1000_spi_eeprom_read_page(struct e1000_hw *hw,
 228                 void *data, u16 off, u16 len, bool intr)
 229 {
 230         u8 op[] = {
 231                 SPI_EEPROM_READ_PAGE,
 232                 (off >> (hw->eeprom.address_bits - 8)) & 0xff, off & 0xff
 233         };
 234
 235         e1000_standby_eeprom(hw);
 236
 237         if (e1000_spi_xfer(hw, 8 + hw->eeprom.address_bits, op, NULL, intr))
 238                 return -1;
 239         if (e1000_spi_xfer(hw, len << 3, NULL, data, intr))
 240                 return -1;
 241
 242         return 0;
 243 }
 244
 245 static int e1000_spi_eeprom_poll_ready(struct e1000_hw *hw, bool intr)
 246 {
 247         int status;
 248         while ((status = e1000_spi_eeprom_read_status(hw, intr)) >= 0) {
 249                 if (!(status & SPI_EEPROM_STATUS_BUSY))
 250                         return 0;
 251         }
 252         return -1;
 253 }
 254
 255 static int e1000_spi_eeprom_dump(struct e1000_hw *hw,
 256                 void *data, u16 off, unsigned int len, bool intr)
 257 {
 258         /* Interruptibly wait for the EEPROM to be ready */
 259         if (e1000_spi_eeprom_poll_ready(hw, intr))
 260                 return -1;
 261
 262         /* Dump each page in sequence */
 263         while (len) {
 264                 /* Calculate the data bytes on this page */
 265                 u16 pg_off = off & (hw->eeprom.page_size - 1);
 266                 u16 pg_len = hw->eeprom.page_size - pg_off;
 267                 if (pg_len > len)
 268                         pg_len = len;
 269
 270                 /* Now dump the page */
 271                 if (e1000_spi_eeprom_read_page(hw, data, off, pg_len, intr))
 272                         return -1;
 273
 274                 /* Otherwise go on to the next page */
 275                 len  -= pg_len;
 276                 off  += pg_len;
 277                 data += pg_len;
 278         }
 279
 280         /* We're done! */
 281         return 0;
 282 }
 283
 284 static int e1000_spi_eeprom_program(struct e1000_hw *hw,
 285                 const void *data, u16 off, u16 len, bool intr)
 286 {
 287         /* Program each page in sequence */
 288         while (len) {
 289                 /* Calculate the data bytes on this page */
 290                 u16 pg_off = off & (hw->eeprom.page_size - 1);
 291                 u16 pg_len = hw->eeprom.page_size - pg_off;
 292                 if (pg_len > len)
 293                         pg_len = len;
 294
 295                 /* Interruptibly wait for the EEPROM to be ready */
 296                 if (e1000_spi_eeprom_poll_ready(hw, intr))
 297                         return -1;
 298
 299                 /* Enable write access */
 300                 if (e1000_spi_eeprom_enable_wr(hw, intr))
 301                         return -1;
 302
 303                 /* Now program the page */
 304                 if (e1000_spi_eeprom_write_page(hw, data, off, pg_len, intr))
 305                         return -1;
 306
 307                 /* Otherwise go on to the next page */
 308                 len  -= pg_len;
 309                 off  += pg_len;
 310                 data += pg_len;
 311         }
 312
 313         /* Wait for the last write to complete */
 314         if (e1000_spi_eeprom_poll_ready(hw, intr))
 315                 return -1;
 316
 317         /* We're done! */
 318         return 0;
 319 }
 320
 321 static int do_e1000_spi_show(cmd_tbl_t *cmdtp, struct e1000_hw *hw,
 322                 int argc, char * const argv[])
 323 {
 324         unsigned int length = 0;
 325         u16 i, offset = 0;
 326         u8 *buffer;
 327         int err;
 328
 329         if (argc > 2) {
 330                 cmd_usage(cmdtp);
 331                 return 1;
 332         }
 333
 334         /* Parse the offset and length */
 335         if (argc >= 1)
 336                 offset = simple_strtoul(argv[0], NULL, 0);
 337         if (argc == 2)
 338                 length = simple_strtoul(argv[1], NULL, 0);
 339         else if (offset < (hw->eeprom.word_size << 1))
 340                 length = (hw->eeprom.word_size << 1) - offset;
 341
 342         /* Extra sanity checks */
 343         if (!length) {
 344                 E1000_ERR(hw->nic, "Requested zero-sized dump!\n");
 345                 return 1;
 346         }
 347         if ((0x10000 < length) || (0x10000 - length < offset)) {
 348                 E1000_ERR(hw->nic, "Can't dump past 0xFFFF!\n");
 349                 return 1;
 350         }
 351
 352         /* Allocate a buffer to hold stuff */
 353         buffer = malloc(length);
 354         if (!buffer) {
 355                 E1000_ERR(hw->nic, "Out of Memory!\n");
 356                 return 1;
 357         }
 358
 359         /* Acquire the EEPROM and perform the dump */
 360         if (e1000_acquire_eeprom(hw)) {
 361                 E1000_ERR(hw->nic, "EEPROM SPI cannot be acquired!\n");
 362                 free(buffer);
 363                 return 1;
 364         }
 365         err = e1000_spi_eeprom_dump(hw, buffer, offset, length, true);
 366         e1000_release_eeprom(hw);
 367         if (err) {
 368                 E1000_ERR(hw->nic, "Interrupted!\n");
 369                 free(buffer);
 370                 return 1;
 371         }
 372
 373         /* Now hexdump the result */
 374         printf("%s: ===== Intel e1000 EEPROM (0x%04hX - 0x%04hX) =====",
 375                         hw->nic->name, offset, offset + length - 1);
 376         for (i = 0; i < length; i++) {
 377                 if ((i & 0xF) == 0)
 378                         printf("\n%s: %04hX: ", hw->nic->name, offset + i);
 379                 else if ((i & 0xF) == 0x8)
 380                         printf(" ");
 381                 printf(" %02hx", buffer[i]);
 382         }
 383         printf("\n");
 384
 385         /* Success! */
 386         free(buffer);
 387         return 0;
 388 }
 389
 390 static int do_e1000_spi_dump(cmd_tbl_t *cmdtp, struct e1000_hw *hw,
 391                 int argc, char * const argv[])
 392 {
 393         unsigned int length;
 394         u16 offset;
 395         void *dest;
 396
 397         if (argc != 3) {
 398                 cmd_usage(cmdtp);
 399                 return 1;
 400         }
 401
 402         /* Parse the arguments */
 403         dest = (void *)simple_strtoul(argv[0], NULL, 16);
 404         offset = simple_strtoul(argv[1], NULL, 0);
 405         length = simple_strtoul(argv[2], NULL, 0);
 406
 407         /* Extra sanity checks */
 408         if (!length) {
 409                 E1000_ERR(hw->nic, "Requested zero-sized dump!\n");
 410                 return 1;
 411         }
 412         if ((0x10000 < length) || (0x10000 - length < offset)) {
 413                 E1000_ERR(hw->nic, "Can't dump past 0xFFFF!\n");
 414                 return 1;
 415         }
 416
 417         /* Acquire the EEPROM */
 418         if (e1000_acquire_eeprom(hw)) {
 419                 E1000_ERR(hw->nic, "EEPROM SPI cannot be acquired!\n");
 420                 return 1;
 421         }
 422
 423         /* Perform the programming operation */
 424         if (e1000_spi_eeprom_dump(hw, dest, offset, length, true) < 0) {
 425                 E1000_ERR(hw->nic, "Interrupted!\n");
 426                 e1000_release_eeprom(hw);
 427                 return 1;
 428         }
 429
 430         e1000_release_eeprom(hw);
 431         printf("%s: ===== EEPROM DUMP COMPLETE =====\n", hw->nic->name);
 432         return 0;
 433 }
 434
 435 static int do_e1000_spi_program(cmd_tbl_t *cmdtp, struct e1000_hw *hw,
 436                 int argc, char * const argv[])
 437 {
 438         unsigned int length;
 439         const void *source;
 440         u16 offset;
 441
 442         if (argc != 3) {
 443                 cmd_usage(cmdtp);
 444                 return 1;
 445         }
 446
 447         /* Parse the arguments */
 448         source = (const void *)simple_strtoul(argv[0], NULL, 16);
 449         offset = simple_strtoul(argv[1], NULL, 0);
 450         length = simple_strtoul(argv[2], NULL, 0);
 451
 452         /* Acquire the EEPROM */
 453         if (e1000_acquire_eeprom(hw)) {
 454                 E1000_ERR(hw->nic, "EEPROM SPI cannot be acquired!\n");
 455                 return 1;
 456         }
 457
 458         /* Perform the programming operation */
 459         if (e1000_spi_eeprom_program(hw, source, offset, length, true) < 0) {
 460                 E1000_ERR(hw->nic, "Interrupted!\n");
 461                 e1000_release_eeprom(hw);
 462                 return 1;
 463         }
 464
 465         e1000_release_eeprom(hw);
 466         printf("%s: ===== EEPROM PROGRAMMED =====\n", hw->nic->name);
 467         return 0;
 468 }
 469
 470 static int do_e1000_spi_checksum(cmd_tbl_t *cmdtp, struct e1000_hw *hw,
 471                 int argc, char * const argv[])
 472 {
 473         uint16_t i, length, checksum = 0, checksum_reg;
 474         uint16_t *buffer;
 475         bool upd;
 476
 477         if (argc == 0)
 478                 upd = 0;
 479         else if ((argc == 1) && !strcmp(argv[0], "update"))
 480                 upd = 1;
 481         else {
 482                 cmd_usage(cmdtp);
 483                 return 1;
 484         }
 485
 486         /* Allocate a temporary buffer */
 487         length = sizeof(uint16_t) * (EEPROM_CHECKSUM_REG + 1);
 488         buffer = malloc(length);
 489         if (!buffer) {
 490                 E1000_ERR(hw->nic, "Unable to allocate EEPROM buffer!\n");
 491                 return 1;
 492         }
 493
 494         /* Acquire the EEPROM */
 495         if (e1000_acquire_eeprom(hw)) {
 496                 E1000_ERR(hw->nic, "EEPROM SPI cannot be acquired!\n");
 497                 return 1;
 498         }
 499
 500         /* Read the EEPROM */
 501         if (e1000_spi_eeprom_dump(hw, buffer, 0, length, true) < 0) {
 502                 E1000_ERR(hw->nic, "Interrupted!\n");
 503                 e1000_release_eeprom(hw);
 504                 return 1;
 505         }
 506
 507         /* Compute the checksum and read the expected value */
 508         for (i = 0; i < EEPROM_CHECKSUM_REG; i++)
 509                 checksum += le16_to_cpu(buffer[i]);
 510         checksum = ((uint16_t)EEPROM_SUM) - checksum;
 511         checksum_reg = le16_to_cpu(buffer[i]);
 512
 513         /* Verify it! */
 514         if (checksum_reg == checksum) {
 515                 printf("%s: INFO: EEPROM checksum is correct! (0x%04hx)\n",
 516                                 hw->nic->name, checksum);
 517                 e1000_release_eeprom(hw);
 518                 return 0;
 519         }
 520
 521         /* Hrm, verification failed, print an error */
 522         E1000_ERR(hw->nic, "EEPROM checksum is incorrect!\n");
 523         E1000_ERR(hw->nic, "  ...register was 0x%04hx, calculated 0x%04hx\n",
 524                         checksum_reg, checksum);
 525
 526         /* If they didn't ask us to update it, just return an error */
 527         if (!upd) {
 528                 e1000_release_eeprom(hw);
 529                 return 1;
 530         }
 531
 532         /* Ok, correct it! */
 533         printf("%s: Reprogramming the EEPROM checksum...\n", hw->nic->name);
 534         buffer[i] = cpu_to_le16(checksum);
 535         if (e1000_spi_eeprom_program(hw, &buffer[i], i * sizeof(uint16_t),
 536                         sizeof(uint16_t), true)) {
 537                 E1000_ERR(hw->nic, "Interrupted!\n");
 538                 e1000_release_eeprom(hw);
 539                 return 1;
 540         }
 541
 542         e1000_release_eeprom(hw);
 543         return 0;
 544 }
 545
 546 int do_e1000_spi(cmd_tbl_t *cmdtp, struct e1000_hw *hw,
 547                 int argc, char * const argv[])
 548 {
 549         if (argc < 1) {
 550                 cmd_usage(cmdtp);
 551                 return 1;
 552         }
 553
 554         /* Make sure it has an SPI chip */
 555         if (hw->eeprom.type != e1000_eeprom_spi) {
 556                 E1000_ERR(hw->nic, "No attached SPI EEPROM found!\n");
 557                 return 1;
 558         }
 559
 560         /* Check the eeprom sub-sub-command arguments */
 561         if (!strcmp(argv[0], "show"))
 562                 return do_e1000_spi_show(cmdtp, hw, argc - 1, argv + 1);
 563
 564         if (!strcmp(argv[0], "dump"))
 565                 return do_e1000_spi_dump(cmdtp, hw, argc - 1, argv + 1);
 566
 567         if (!strcmp(argv[0], "program"))
 568                 return do_e1000_spi_program(cmdtp, hw, argc - 1, argv + 1);
 569
 570         if (!strcmp(argv[0], "checksum"))
 571                 return do_e1000_spi_checksum(cmdtp, hw, argc - 1, argv + 1);
 572
 573         cmd_usage(cmdtp);
 574         return 1;
 575 }
 576
 577 #endif /* not CONFIG_CMD_E1000 */