drivers/net/ixgb/ixgb_ee.c

   1 /*******************************************************************************
   2
   3   Intel PRO/10GbE Linux driver
   4   Copyright(c) 1999 - 2008 Intel Corporation.
   5
   6   This program is free software; you can redistribute it and/or modify it
   7   under the terms and conditions of the GNU General Public License,
   8   version 2, as published by the Free Software Foundation.
   9
  10   This program is distributed in the hope it will be useful, but WITHOUT
  11   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12   FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13   more details.
  14
  15   You should have received a copy of the GNU General Public License along with
  16   this program; if not, write to the Free Software Foundation, Inc.,
  17   51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
  18
  19   The full GNU General Public License is included in this distribution in
  20   the file called "COPYING".
  21
  22   Contact Information:
  23   Linux NICS <linux.nics@intel.com>
  24   e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
  25   Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
  26
  27 *******************************************************************************/
  28
  29 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  30
  31 #include "ixgb_hw.h"
  32 #include "ixgb_ee.h"
  33 /* Local prototypes */
  34 static u16 ixgb_shift_in_bits(struct ixgb_hw *hw);
  35
  36 static void ixgb_shift_out_bits(struct ixgb_hw *hw,
  37                                 u16 data,
  38                                 u16 count);
  39 static void ixgb_standby_eeprom(struct ixgb_hw *hw);
  40
  41 static bool ixgb_wait_eeprom_command(struct ixgb_hw *hw);
  42
  43 static void ixgb_cleanup_eeprom(struct ixgb_hw *hw);
  44
  45 /******************************************************************************
  46  * Raises the EEPROM's clock input.
  47  *
  48  * hw - Struct containing variables accessed by shared code
  49  * eecd_reg - EECD's current value
  50  *****************************************************************************/
  51 static void
  52 ixgb_raise_clock(struct ixgb_hw *hw,
  53                   u32 *eecd_reg)
  54 {
  55         /* Raise the clock input to the EEPROM (by setting the SK bit), and then
  56          *  wait 50 microseconds.
  57          */
  58         *eecd_reg = *eecd_reg | IXGB_EECD_SK;
  59         IXGB_WRITE_REG(hw, EECD, *eecd_reg);
  60         udelay(50);
  61 }
  62
  63 /******************************************************************************
  64  * Lowers the EEPROM's clock input.
  65  *
  66  * hw - Struct containing variables accessed by shared code
  67  * eecd_reg - EECD's current value
  68  *****************************************************************************/
  69 static void
  70 ixgb_lower_clock(struct ixgb_hw *hw,
  71                   u32 *eecd_reg)
  72 {
  73         /* Lower the clock input to the EEPROM (by clearing the SK bit), and then
  74          * wait 50 microseconds.
  75          */
  76         *eecd_reg = *eecd_reg & ~IXGB_EECD_SK;
  77         IXGB_WRITE_REG(hw, EECD, *eecd_reg);
  78         udelay(50);
  79 }
  80
  81 /******************************************************************************
  82  * Shift data bits out to the EEPROM.
  83  *
  84  * hw - Struct containing variables accessed by shared code
  85  * data - data to send to the EEPROM
  86  * count - number of bits to shift out
  87  *****************************************************************************/
  88 static void
  89 ixgb_shift_out_bits(struct ixgb_hw *hw,
  90                                          u16 data,
  91                                          u16 count)
  92 {
  93         u32 eecd_reg;
  94         u32 mask;
  95
  96         /* We need to shift "count" bits out to the EEPROM. So, value in the
  97          * "data" parameter will be shifted out to the EEPROM one bit at a time.
  98          * In order to do this, "data" must be broken down into bits.
  99          */
 100         mask = 0x01 << (count - 1);
 101         eecd_reg = IXGB_READ_REG(hw, EECD);
 102         eecd_reg &= ~(IXGB_EECD_DO | IXGB_EECD_DI);
 103         do {
 104                 /* A "1" is shifted out to the EEPROM by setting bit "DI" to a "1",
 105                  * and then raising and then lowering the clock (the SK bit controls
 106                  * the clock input to the EEPROM).  A "0" is shifted out to the EEPROM
 107                  * by setting "DI" to "0" and then raising and then lowering the clock.
 108                  */
 109                 eecd_reg &= ~IXGB_EECD_DI;
 110
 111                 if (data & mask)
 112                         eecd_reg |= IXGB_EECD_DI;
 113
 114                 IXGB_WRITE_REG(hw, EECD, eecd_reg);
 115
 116                 udelay(50);
 117
 118                 ixgb_raise_clock(hw, &eecd_reg);
 119                 ixgb_lower_clock(hw, &eecd_reg);
 120
 121                 mask = mask >> 1;
 122
 123         } while (mask);
 124
 125         /* We leave the "DI" bit set to "0" when we leave this routine. */
 126         eecd_reg &= ~IXGB_EECD_DI;
 127         IXGB_WRITE_REG(hw, EECD, eecd_reg);
 128 }
 129
 130 /******************************************************************************
 131  * Shift data bits in from the EEPROM
 132  *
 133  * hw - Struct containing variables accessed by shared code
 134  *****************************************************************************/
 135 static u16
 136 ixgb_shift_in_bits(struct ixgb_hw *hw)
 137 {
 138         u32 eecd_reg;
 139         u32 i;
 140         u16 data;
 141
 142         /* In order to read a register from the EEPROM, we need to shift 16 bits
 143          * in from the EEPROM. Bits are "shifted in" by raising the clock input to
 144          * the EEPROM (setting the SK bit), and then reading the value of the "DO"
 145          * bit.  During this "shifting in" process the "DI" bit should always be
 146          * clear..
 147          */
 148
 149         eecd_reg = IXGB_READ_REG(hw, EECD);
 150
 151         eecd_reg &= ~(IXGB_EECD_DO | IXGB_EECD_DI);
 152         data = 0;
 153
 154         for (i = 0; i < 16; i++) {
 155                 data = data << 1;
 156                 ixgb_raise_clock(hw, &eecd_reg);
 157
 158                 eecd_reg = IXGB_READ_REG(hw, EECD);
 159
 160                 eecd_reg &= ~(IXGB_EECD_DI);
 161                 if (eecd_reg & IXGB_EECD_DO)
 162                         data |= 1;
 163
 164                 ixgb_lower_clock(hw, &eecd_reg);
 165         }
 166
 167         return data;
 168 }
 169
 170 /******************************************************************************
 171  * Prepares EEPROM for access
 172  *
 173  * hw - Struct containing variables accessed by shared code
 174  *
 175  * Lowers EEPROM clock. Clears input pin. Sets the chip select pin. This
 176  * function should be called before issuing a command to the EEPROM.
 177  *****************************************************************************/
 178 static void
 179 ixgb_setup_eeprom(struct ixgb_hw *hw)
 180 {
 181         u32 eecd_reg;
 182
 183         eecd_reg = IXGB_READ_REG(hw, EECD);
 184
 185         /*  Clear SK and DI  */
 186         eecd_reg &= ~(IXGB_EECD_SK | IXGB_EECD_DI);
 187         IXGB_WRITE_REG(hw, EECD, eecd_reg);
 188
 189         /*  Set CS  */
 190         eecd_reg |= IXGB_EECD_CS;
 191         IXGB_WRITE_REG(hw, EECD, eecd_reg);
 192 }
 193
 194 /******************************************************************************
 195  * Returns EEPROM to a "standby" state
 196  *
 197  * hw - Struct containing variables accessed by shared code
 198  *****************************************************************************/
 199 static void
 200 ixgb_standby_eeprom(struct ixgb_hw *hw)
 201 {
 202         u32 eecd_reg;
 203
 204         eecd_reg = IXGB_READ_REG(hw, EECD);
 205
 206         /*  Deselect EEPROM  */
 207         eecd_reg &= ~(IXGB_EECD_CS | IXGB_EECD_SK);
 208         IXGB_WRITE_REG(hw, EECD, eecd_reg);
 209         udelay(50);
 210
 211         /*  Clock high  */
 212         eecd_reg |= IXGB_EECD_SK;
 213         IXGB_WRITE_REG(hw, EECD, eecd_reg);
 214         udelay(50);
 215
 216         /*  Select EEPROM  */
 217         eecd_reg |= IXGB_EECD_CS;
 218         IXGB_WRITE_REG(hw, EECD, eecd_reg);
 219         udelay(50);
 220
 221         /*  Clock low  */
 222         eecd_reg &= ~IXGB_EECD_SK;
 223         IXGB_WRITE_REG(hw, EECD, eecd_reg);
 224         udelay(50);
 225 }
 226
 227 /******************************************************************************
 228  * Raises then lowers the EEPROM's clock pin
 229  *
 230  * hw - Struct containing variables accessed by shared code
 231  *****************************************************************************/
 232 static void
 233 ixgb_clock_eeprom(struct ixgb_hw *hw)
 234 {
 235         u32 eecd_reg;
 236
 237         eecd_reg = IXGB_READ_REG(hw, EECD);
 238
 239         /*  Rising edge of clock  */
 240         eecd_reg |= IXGB_EECD_SK;
 241         IXGB_WRITE_REG(hw, EECD, eecd_reg);
 242         udelay(50);
 243
 244         /*  Falling edge of clock  */
 245         eecd_reg &= ~IXGB_EECD_SK;
 246         IXGB_WRITE_REG(hw, EECD, eecd_reg);
 247         udelay(50);
 248 }
 249
 250 /******************************************************************************
 251  * Terminates a command by lowering the EEPROM's chip select pin
 252  *
 253  * hw - Struct containing variables accessed by shared code
 254  *****************************************************************************/
 255 static void
 256 ixgb_cleanup_eeprom(struct ixgb_hw *hw)
 257 {
 258         u32 eecd_reg;
 259
 260         eecd_reg = IXGB_READ_REG(hw, EECD);
 261
 262         eecd_reg &= ~(IXGB_EECD_CS | IXGB_EECD_DI);
 263
 264         IXGB_WRITE_REG(hw, EECD, eecd_reg);
 265
 266         ixgb_clock_eeprom(hw);
 267 }
 268
 269 /******************************************************************************
 270  * Waits for the EEPROM to finish the current command.
 271  *
 272  * hw - Struct containing variables accessed by shared code
 273  *
 274  * The command is done when the EEPROM's data out pin goes high.
 275  *
 276  * Returns:
 277  *      true: EEPROM data pin is high before timeout.
 278  *      false:  Time expired.
 279  *****************************************************************************/
 280 static bool
 281 ixgb_wait_eeprom_command(struct ixgb_hw *hw)
 282 {
 283         u32 eecd_reg;
 284         u32 i;
 285
 286         /* Toggle the CS line.  This in effect tells to EEPROM to actually execute
 287          * the command in question.
 288          */
 289         ixgb_standby_eeprom(hw);
 290
 291         /* Now read DO repeatedly until is high (equal to '1').  The EEPROM will
 292          * signal that the command has been completed by raising the DO signal.
 293          * If DO does not go high in 10 milliseconds, then error out.
 294          */
 295         for (i = 0; i < 200; i++) {
 296                 eecd_reg = IXGB_READ_REG(hw, EECD);
 297
 298                 if (eecd_reg & IXGB_EECD_DO)
 299                         return true;
 300
 301                 udelay(50);
 302         }
 303         ASSERT(0);
 304         return false;
 305 }
 306
 307 /******************************************************************************
 308  * Verifies that the EEPROM has a valid checksum
 309  *
 310  * hw - Struct containing variables accessed by shared code
 311  *
 312  * Reads the first 64 16 bit words of the EEPROM and sums the values read.
 313  * If the sum of the 64 16 bit words is 0xBABA, the EEPROM's checksum is
 314  * valid.
 315  *
 316  * Returns:
 317  *  true: Checksum is valid
 318  *  false: Checksum is not valid.
 319  *****************************************************************************/
 320 bool
 321 ixgb_validate_eeprom_checksum(struct ixgb_hw *hw)
 322 {
 323         u16 checksum = 0;
 324         u16 i;
 325
 326         for (i = 0; i < (EEPROM_CHECKSUM_REG + 1); i++)
 327                 checksum += ixgb_read_eeprom(hw, i);
 328
 329         if (checksum == (u16) EEPROM_SUM)
 330                 return true;
 331         else
 332                 return false;
 333 }
 334
 335 /******************************************************************************
 336  * Calculates the EEPROM checksum and writes it to the EEPROM
 337  *
 338  * hw - Struct containing variables accessed by shared code
 339  *
 340  * Sums the first 63 16 bit words of the EEPROM. Subtracts the sum from 0xBABA.
 341  * Writes the difference to word offset 63 of the EEPROM.
 342  *****************************************************************************/
 343 void
 344 ixgb_update_eeprom_checksum(struct ixgb_hw *hw)
 345 {
 346         u16 checksum = 0;
 347         u16 i;
 348
 349         for (i = 0; i < EEPROM_CHECKSUM_REG; i++)
 350                 checksum += ixgb_read_eeprom(hw, i);
 351
 352         checksum = (u16) EEPROM_SUM - checksum;
 353
 354         ixgb_write_eeprom(hw, EEPROM_CHECKSUM_REG, checksum);
 355 }
 356
 357 /******************************************************************************
 358  * Writes a 16 bit word to a given offset in the EEPROM.
 359  *
 360  * hw - Struct containing variables accessed by shared code
 361  * reg - offset within the EEPROM to be written to
 362  * data - 16 bit word to be written to the EEPROM
 363  *
 364  * If ixgb_update_eeprom_checksum is not called after this function, the
 365  * EEPROM will most likely contain an invalid checksum.
 366  *
 367  *****************************************************************************/
 368 void
 369 ixgb_write_eeprom(struct ixgb_hw *hw, u16 offset, u16 data)
 370 {
 371         struct ixgb_ee_map_type *ee_map = (struct ixgb_ee_map_type *)hw->eeprom;
 372
 373         /* Prepare the EEPROM for writing */
 374         ixgb_setup_eeprom(hw);
 375
 376         /*  Send the 9-bit EWEN (write enable) command to the EEPROM (5-bit opcode
 377          *  plus 4-bit dummy).  This puts the EEPROM into write/erase mode.
 378          */
 379         ixgb_shift_out_bits(hw, EEPROM_EWEN_OPCODE, 5);
 380         ixgb_shift_out_bits(hw, 0, 4);
 381
 382         /*  Prepare the EEPROM  */
 383         ixgb_standby_eeprom(hw);
 384
 385         /*  Send the Write command (3-bit opcode + 6-bit addr)  */
 386         ixgb_shift_out_bits(hw, EEPROM_WRITE_OPCODE, 3);
 387         ixgb_shift_out_bits(hw, offset, 6);
 388
 389         /*  Send the data  */
 390         ixgb_shift_out_bits(hw, data, 16);
 391
 392         ixgb_wait_eeprom_command(hw);
 393
 394         /*  Recover from write  */
 395         ixgb_standby_eeprom(hw);
 396
 397         /* Send the 9-bit EWDS (write disable) command to the EEPROM (5-bit
 398          * opcode plus 4-bit dummy).  This takes the EEPROM out of write/erase
 399          * mode.
 400          */
 401         ixgb_shift_out_bits(hw, EEPROM_EWDS_OPCODE, 5);
 402         ixgb_shift_out_bits(hw, 0, 4);
 403
 404         /*  Done with writing  */
 405         ixgb_cleanup_eeprom(hw);
 406
 407         /* clear the init_ctrl_reg_1 to signify that the cache is invalidated */
 408         ee_map->init_ctrl_reg_1 = cpu_to_le16(EEPROM_ICW1_SIGNATURE_CLEAR);
 409 }
 410
 411 /******************************************************************************
 412  * Reads a 16 bit word from the EEPROM.
 413  *
 414  * hw - Struct containing variables accessed by shared code
 415  * offset - offset of 16 bit word in the EEPROM to read
 416  *
 417  * Returns:
 418  *  The 16-bit value read from the eeprom
 419  *****************************************************************************/
 420 u16
 421 ixgb_read_eeprom(struct ixgb_hw *hw,
 422                   u16 offset)
 423 {
 424         u16 data;
 425
 426         /*  Prepare the EEPROM for reading  */
 427         ixgb_setup_eeprom(hw);
 428
 429         /*  Send the READ command (opcode + addr)  */
 430         ixgb_shift_out_bits(hw, EEPROM_READ_OPCODE, 3);
 431         /*
 432          * We have a 64 word EEPROM, there are 6 address bits
 433          */
 434         ixgb_shift_out_bits(hw, offset, 6);
 435
 436         /*  Read the data  */
 437         data = ixgb_shift_in_bits(hw);
 438
 439         /*  End this read operation  */
 440         ixgb_standby_eeprom(hw);
 441
 442         return data;
 443 }
 444
 445 /******************************************************************************
 446  * Reads eeprom and stores data in shared structure.
 447  * Validates eeprom checksum and eeprom signature.
 448  *
 449  * hw - Struct containing variables accessed by shared code
 450  *
 451  * Returns:
 452  *      true: if eeprom read is successful
 453  *      false: otherwise.
 454  *****************************************************************************/
 455 bool
 456 ixgb_get_eeprom_data(struct ixgb_hw *hw)
 457 {
 458         u16 i;
 459         u16 checksum = 0;
 460         struct ixgb_ee_map_type *ee_map;
 461
 462         ENTER();
 463
 464         ee_map = (struct ixgb_ee_map_type *)hw->eeprom;
 465
 466         pr_debug("Reading eeprom data\n");
 467         for (i = 0; i < IXGB_EEPROM_SIZE ; i++) {
 468                 u16 ee_data;
 469                 ee_data = ixgb_read_eeprom(hw, i);
 470                 checksum += ee_data;
 471                 hw->eeprom[i] = cpu_to_le16(ee_data);
 472         }
 473
 474         if (checksum != (u16) EEPROM_SUM) {
 475                 pr_debug("Checksum invalid\n");
 476                 /* clear the init_ctrl_reg_1 to signify that the cache is
 477                  * invalidated */
 478                 ee_map->init_ctrl_reg_1 = cpu_to_le16(EEPROM_ICW1_SIGNATURE_CLEAR);
 479                 return false;
 480         }
 481
 482         if ((ee_map->init_ctrl_reg_1 & cpu_to_le16(EEPROM_ICW1_SIGNATURE_MASK))
 483                  != cpu_to_le16(EEPROM_ICW1_SIGNATURE_VALID)) {
 484                 pr_debug("Signature invalid\n");
 485                 return false;
 486         }
 487
 488         return true;
 489 }
 490
 491 /******************************************************************************
 492  * Local function to check if the eeprom signature is good
 493  * If the eeprom signature is good, calls ixgb)get_eeprom_data.
 494  *
 495  * hw - Struct containing variables accessed by shared code
 496  *
 497  * Returns:
 498  *      true: eeprom signature was good and the eeprom read was successful
 499  *      false: otherwise.
 500  ******************************************************************************/
 501 static bool
 502 ixgb_check_and_get_eeprom_data (struct ixgb_hw* hw)
 503 {
 504         struct ixgb_ee_map_type *ee_map = (struct ixgb_ee_map_type *)hw->eeprom;
 505
 506         if ((ee_map->init_ctrl_reg_1 & cpu_to_le16(EEPROM_ICW1_SIGNATURE_MASK))
 507             == cpu_to_le16(EEPROM_ICW1_SIGNATURE_VALID)) {
 508                 return true;
 509         } else {
 510                 return ixgb_get_eeprom_data(hw);
 511         }
 512 }
 513
 514 /******************************************************************************
 515  * return a word from the eeprom
 516  *
 517  * hw - Struct containing variables accessed by shared code
 518  * index - Offset of eeprom word
 519  *
 520  * Returns:
 521  *          Word at indexed offset in eeprom, if valid, 0 otherwise.
 522  ******************************************************************************/
 523 __le16
 524 ixgb_get_eeprom_word(struct ixgb_hw *hw, u16 index)
 525 {
 526
 527         if ((index < IXGB_EEPROM_SIZE) &&
 528                 (ixgb_check_and_get_eeprom_data(hw) == true)) {
 529            return hw->eeprom[index];
 530         }
 531
 532         return 0;
 533 }
 534
 535 /******************************************************************************
 536  * return the mac address from EEPROM
 537  *
 538  * hw       - Struct containing variables accessed by shared code
 539  * mac_addr - Ethernet Address if EEPROM contents are valid, 0 otherwise
 540  *
 541  * Returns: None.
 542  ******************************************************************************/
 543 void
 544 ixgb_get_ee_mac_addr(struct ixgb_hw *hw,
 545                         u8 *mac_addr)
 546 {
 547         int i;
 548         struct ixgb_ee_map_type *ee_map = (struct ixgb_ee_map_type *)hw->eeprom;
 549
 550         ENTER();
 551
 552         if (ixgb_check_and_get_eeprom_data(hw) == true) {
 553                 for (i = 0; i < IXGB_ETH_LENGTH_OF_ADDRESS; i++) {
 554                         mac_addr[i] = ee_map->mac_addr[i];
 555                 }
 556                 pr_debug("eeprom mac address = %pM\n", mac_addr);
 557         }
 558 }
 559
 560
 561 /******************************************************************************
 562  * return the Printed Board Assembly number from EEPROM
 563  *
 564  * hw - Struct containing variables accessed by shared code
 565  *
 566  * Returns:
 567  *          PBA number if EEPROM contents are valid, 0 otherwise
 568  ******************************************************************************/
 569 u32
 570 ixgb_get_ee_pba_number(struct ixgb_hw *hw)
 571 {
 572         if (ixgb_check_and_get_eeprom_data(hw) == true)
 573                 return le16_to_cpu(hw->eeprom[EEPROM_PBA_1_2_REG])
 574                         | (le16_to_cpu(hw->eeprom[EEPROM_PBA_3_4_REG])<<16);
 575
 576         return 0;
 577 }
 578
 579
 580 /******************************************************************************
 581  * return the Device Id from EEPROM
 582  *
 583  * hw - Struct containing variables accessed by shared code
 584  *
 585  * Returns:
 586  *          Device Id if EEPROM contents are valid, 0 otherwise
 587  ******************************************************************************/
 588 u16
 589 ixgb_get_ee_device_id(struct ixgb_hw *hw)
 590 {
 591         struct ixgb_ee_map_type *ee_map = (struct ixgb_ee_map_type *)hw->eeprom;
 592
 593         if (ixgb_check_and_get_eeprom_data(hw) == true)
 594                 return le16_to_cpu(ee_map->device_id);
 595
 596         return 0;
 597 }
 598