drivers/net/ethernet/intel/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         IXGB_WRITE_FLUSH(hw);
  61         udelay(50);
  62 }
  63
  64 /******************************************************************************
  65  * Lowers the EEPROM's clock input.
  66  *
  67  * hw - Struct containing variables accessed by shared code
  68  * eecd_reg - EECD's current value
  69  *****************************************************************************/
  70 static void
  71 ixgb_lower_clock(struct ixgb_hw *hw,
  72                   u32 *eecd_reg)
  73 {
  74         /* Lower the clock input to the EEPROM (by clearing the SK bit), and then
  75          * wait 50 microseconds.
  76          */
  77         *eecd_reg = *eecd_reg & ~IXGB_EECD_SK;
  78         IXGB_WRITE_REG(hw, EECD, *eecd_reg);
  79         IXGB_WRITE_FLUSH(hw);
  80         udelay(50);
  81 }
  82
  83 /******************************************************************************
  84  * Shift data bits out to the EEPROM.
  85  *
  86  * hw - Struct containing variables accessed by shared code
  87  * data - data to send to the EEPROM
  88  * count - number of bits to shift out
  89  *****************************************************************************/
  90 static void
  91 ixgb_shift_out_bits(struct ixgb_hw *hw,
  92                                          u16 data,
  93                                          u16 count)
  94 {
  95         u32 eecd_reg;
  96         u32 mask;
  97
  98         /* We need to shift "count" bits out to the EEPROM. So, value in the
  99          * "data" parameter will be shifted out to the EEPROM one bit at a time.
 100          * In order to do this, "data" must be broken down into bits.
 101          */
 102         mask = 0x01 << (count - 1);
 103         eecd_reg = IXGB_READ_REG(hw, EECD);
 104         eecd_reg &= ~(IXGB_EECD_DO | IXGB_EECD_DI);
 105         do {
 106                 /* A "1" is shifted out to the EEPROM by setting bit "DI" to a "1",
 107                  * and then raising and then lowering the clock (the SK bit controls
 108                  * the clock input to the EEPROM).  A "0" is shifted out to the EEPROM
 109                  * by setting "DI" to "0" and then raising and then lowering the clock.
 110                  */
 111                 eecd_reg &= ~IXGB_EECD_DI;
 112
 113                 if (data & mask)
 114                         eecd_reg |= IXGB_EECD_DI;
 115
 116                 IXGB_WRITE_REG(hw, EECD, eecd_reg);
 117                 IXGB_WRITE_FLUSH(hw);
 118
 119                 udelay(50);
 120
 121                 ixgb_raise_clock(hw, &eecd_reg);
 122                 ixgb_lower_clock(hw, &eecd_reg);
 123
 124                 mask = mask >> 1;
 125
 126         } while (mask);
 127
 128         /* We leave the "DI" bit set to "0" when we leave this routine. */
 129         eecd_reg &= ~IXGB_EECD_DI;
 130         IXGB_WRITE_REG(hw, EECD, eecd_reg);
 131 }
 132
 133 /******************************************************************************
 134  * Shift data bits in from the EEPROM
 135  *
 136  * hw - Struct containing variables accessed by shared code
 137  *****************************************************************************/
 138 static u16
 139 ixgb_shift_in_bits(struct ixgb_hw *hw)
 140 {
 141         u32 eecd_reg;
 142         u32 i;
 143         u16 data;
 144
 145         /* In order to read a register from the EEPROM, we need to shift 16 bits
 146          * in from the EEPROM. Bits are "shifted in" by raising the clock input to
 147          * the EEPROM (setting the SK bit), and then reading the value of the "DO"
 148          * bit.  During this "shifting in" process the "DI" bit should always be
 149          * clear..
 150          */
 151
 152         eecd_reg = IXGB_READ_REG(hw, EECD);
 153
 154         eecd_reg &= ~(IXGB_EECD_DO | IXGB_EECD_DI);
 155         data = 0;
 156
 157         for (i = 0; i < 16; i++) {
 158                 data = data << 1;
 159                 ixgb_raise_clock(hw, &eecd_reg);
 160
 161                 eecd_reg = IXGB_READ_REG(hw, EECD);
 162
 163                 eecd_reg &= ~(IXGB_EECD_DI);
 164                 if (eecd_reg & IXGB_EECD_DO)
 165                         data |= 1;
 166
 167                 ixgb_lower_clock(hw, &eecd_reg);
 168         }
 169
 170         return data;
 171 }
 172
 173 /******************************************************************************
 174  * Prepares EEPROM for access
 175  *
 176  * hw - Struct containing variables accessed by shared code
 177  *
 178  * Lowers EEPROM clock. Clears input pin. Sets the chip select pin. This
 179  * function should be called before issuing a command to the EEPROM.
 180  *****************************************************************************/
 181 static void
 182 ixgb_setup_eeprom(struct ixgb_hw *hw)
 183 {
 184         u32 eecd_reg;
 185
 186         eecd_reg = IXGB_READ_REG(hw, EECD);
 187
 188         /*  Clear SK and DI  */
 189         eecd_reg &= ~(IXGB_EECD_SK | IXGB_EECD_DI);
 190         IXGB_WRITE_REG(hw, EECD, eecd_reg);
 191
 192         /*  Set CS  */
 193         eecd_reg |= IXGB_EECD_CS;
 194         IXGB_WRITE_REG(hw, EECD, eecd_reg);
 195 }
 196
 197 /******************************************************************************
 198  * Returns EEPROM to a "standby" state
 199  *
 200  * hw - Struct containing variables accessed by shared code
 201  *****************************************************************************/
 202 static void
 203 ixgb_standby_eeprom(struct ixgb_hw *hw)
 204 {
 205         u32 eecd_reg;
 206
 207         eecd_reg = IXGB_READ_REG(hw, EECD);
 208
 209         /*  Deselect EEPROM  */
 210         eecd_reg &= ~(IXGB_EECD_CS | IXGB_EECD_SK);
 211         IXGB_WRITE_REG(hw, EECD, eecd_reg);
 212         IXGB_WRITE_FLUSH(hw);
 213         udelay(50);
 214
 215         /*  Clock high  */
 216         eecd_reg |= IXGB_EECD_SK;
 217         IXGB_WRITE_REG(hw, EECD, eecd_reg);
 218         IXGB_WRITE_FLUSH(hw);
 219         udelay(50);
 220
 221         /*  Select EEPROM  */
 222         eecd_reg |= IXGB_EECD_CS;
 223         IXGB_WRITE_REG(hw, EECD, eecd_reg);
 224         IXGB_WRITE_FLUSH(hw);
 225         udelay(50);
 226
 227         /*  Clock low  */
 228         eecd_reg &= ~IXGB_EECD_SK;
 229         IXGB_WRITE_REG(hw, EECD, eecd_reg);
 230         IXGB_WRITE_FLUSH(hw);
 231         udelay(50);
 232 }
 233
 234 /******************************************************************************
 235  * Raises then lowers the EEPROM's clock pin
 236  *
 237  * hw - Struct containing variables accessed by shared code
 238  *****************************************************************************/
 239 static void
 240 ixgb_clock_eeprom(struct ixgb_hw *hw)
 241 {
 242         u32 eecd_reg;
 243
 244         eecd_reg = IXGB_READ_REG(hw, EECD);
 245
 246         /*  Rising edge of clock  */
 247         eecd_reg |= IXGB_EECD_SK;
 248         IXGB_WRITE_REG(hw, EECD, eecd_reg);
 249         IXGB_WRITE_FLUSH(hw);
 250         udelay(50);
 251
 252         /*  Falling edge of clock  */
 253         eecd_reg &= ~IXGB_EECD_SK;
 254         IXGB_WRITE_REG(hw, EECD, eecd_reg);
 255         IXGB_WRITE_FLUSH(hw);
 256         udelay(50);
 257 }
 258
 259 /******************************************************************************
 260  * Terminates a command by lowering the EEPROM's chip select pin
 261  *
 262  * hw - Struct containing variables accessed by shared code
 263  *****************************************************************************/
 264 static void
 265 ixgb_cleanup_eeprom(struct ixgb_hw *hw)
 266 {
 267         u32 eecd_reg;
 268
 269         eecd_reg = IXGB_READ_REG(hw, EECD);
 270
 271         eecd_reg &= ~(IXGB_EECD_CS | IXGB_EECD_DI);
 272
 273         IXGB_WRITE_REG(hw, EECD, eecd_reg);
 274
 275         ixgb_clock_eeprom(hw);
 276 }
 277
 278 /******************************************************************************
 279  * Waits for the EEPROM to finish the current command.
 280  *
 281  * hw - Struct containing variables accessed by shared code
 282  *
 283  * The command is done when the EEPROM's data out pin goes high.
 284  *
 285  * Returns:
 286  *      true: EEPROM data pin is high before timeout.
 287  *      false:  Time expired.
 288  *****************************************************************************/
 289 static bool
 290 ixgb_wait_eeprom_command(struct ixgb_hw *hw)
 291 {
 292         u32 eecd_reg;
 293         u32 i;
 294
 295         /* Toggle the CS line.  This in effect tells to EEPROM to actually execute
 296          * the command in question.
 297          */
 298         ixgb_standby_eeprom(hw);
 299
 300         /* Now read DO repeatedly until is high (equal to '1').  The EEPROM will
 301          * signal that the command has been completed by raising the DO signal.
 302          * If DO does not go high in 10 milliseconds, then error out.
 303          */
 304         for (i = 0; i < 200; i++) {
 305                 eecd_reg = IXGB_READ_REG(hw, EECD);
 306
 307                 if (eecd_reg & IXGB_EECD_DO)
 308                         return true;
 309
 310                 udelay(50);
 311         }
 312         ASSERT(0);
 313         return false;
 314 }
 315
 316 /******************************************************************************
 317  * Verifies that the EEPROM has a valid checksum
 318  *
 319  * hw - Struct containing variables accessed by shared code
 320  *
 321  * Reads the first 64 16 bit words of the EEPROM and sums the values read.
 322  * If the sum of the 64 16 bit words is 0xBABA, the EEPROM's checksum is
 323  * valid.
 324  *
 325  * Returns:
 326  *  true: Checksum is valid
 327  *  false: Checksum is not valid.
 328  *****************************************************************************/
 329 bool
 330 ixgb_validate_eeprom_checksum(struct ixgb_hw *hw)
 331 {
 332         u16 checksum = 0;
 333         u16 i;
 334
 335         for (i = 0; i < (EEPROM_CHECKSUM_REG + 1); i++)
 336                 checksum += ixgb_read_eeprom(hw, i);
 337
 338         if (checksum == (u16) EEPROM_SUM)
 339                 return true;
 340         else
 341                 return false;
 342 }
 343
 344 /******************************************************************************
 345  * Calculates the EEPROM checksum and writes it to the EEPROM
 346  *
 347  * hw - Struct containing variables accessed by shared code
 348  *
 349  * Sums the first 63 16 bit words of the EEPROM. Subtracts the sum from 0xBABA.
 350  * Writes the difference to word offset 63 of the EEPROM.
 351  *****************************************************************************/
 352 void
 353 ixgb_update_eeprom_checksum(struct ixgb_hw *hw)
 354 {
 355         u16 checksum = 0;
 356         u16 i;
 357
 358         for (i = 0; i < EEPROM_CHECKSUM_REG; i++)
 359                 checksum += ixgb_read_eeprom(hw, i);
 360
 361         checksum = (u16) EEPROM_SUM - checksum;
 362
 363         ixgb_write_eeprom(hw, EEPROM_CHECKSUM_REG, checksum);
 364 }
 365
 366 /******************************************************************************
 367  * Writes a 16 bit word to a given offset in the EEPROM.
 368  *
 369  * hw - Struct containing variables accessed by shared code
 370  * reg - offset within the EEPROM to be written to
 371  * data - 16 bit word to be written to the EEPROM
 372  *
 373  * If ixgb_update_eeprom_checksum is not called after this function, the
 374  * EEPROM will most likely contain an invalid checksum.
 375  *
 376  *****************************************************************************/
 377 void
 378 ixgb_write_eeprom(struct ixgb_hw *hw, u16 offset, u16 data)
 379 {
 380         struct ixgb_ee_map_type *ee_map = (struct ixgb_ee_map_type *)hw->eeprom;
 381
 382         /* Prepare the EEPROM for writing */
 383         ixgb_setup_eeprom(hw);
 384
 385         /*  Send the 9-bit EWEN (write enable) command to the EEPROM (5-bit opcode
 386          *  plus 4-bit dummy).  This puts the EEPROM into write/erase mode.
 387          */
 388         ixgb_shift_out_bits(hw, EEPROM_EWEN_OPCODE, 5);
 389         ixgb_shift_out_bits(hw, 0, 4);
 390
 391         /*  Prepare the EEPROM  */
 392         ixgb_standby_eeprom(hw);
 393
 394         /*  Send the Write command (3-bit opcode + 6-bit addr)  */
 395         ixgb_shift_out_bits(hw, EEPROM_WRITE_OPCODE, 3);
 396         ixgb_shift_out_bits(hw, offset, 6);
 397
 398         /*  Send the data  */
 399         ixgb_shift_out_bits(hw, data, 16);
 400
 401         ixgb_wait_eeprom_command(hw);
 402
 403         /*  Recover from write  */
 404         ixgb_standby_eeprom(hw);
 405
 406         /* Send the 9-bit EWDS (write disable) command to the EEPROM (5-bit
 407          * opcode plus 4-bit dummy).  This takes the EEPROM out of write/erase
 408          * mode.
 409          */
 410         ixgb_shift_out_bits(hw, EEPROM_EWDS_OPCODE, 5);
 411         ixgb_shift_out_bits(hw, 0, 4);
 412
 413         /*  Done with writing  */
 414         ixgb_cleanup_eeprom(hw);
 415
 416         /* clear the init_ctrl_reg_1 to signify that the cache is invalidated */
 417         ee_map->init_ctrl_reg_1 = cpu_to_le16(EEPROM_ICW1_SIGNATURE_CLEAR);
 418 }
 419
 420 /******************************************************************************
 421  * Reads a 16 bit word from the EEPROM.
 422  *
 423  * hw - Struct containing variables accessed by shared code
 424  * offset - offset of 16 bit word in the EEPROM to read
 425  *
 426  * Returns:
 427  *  The 16-bit value read from the eeprom
 428  *****************************************************************************/
 429 u16
 430 ixgb_read_eeprom(struct ixgb_hw *hw,
 431                   u16 offset)
 432 {
 433         u16 data;
 434
 435         /*  Prepare the EEPROM for reading  */
 436         ixgb_setup_eeprom(hw);
 437
 438         /*  Send the READ command (opcode + addr)  */
 439         ixgb_shift_out_bits(hw, EEPROM_READ_OPCODE, 3);
 440         /*
 441          * We have a 64 word EEPROM, there are 6 address bits
 442          */
 443         ixgb_shift_out_bits(hw, offset, 6);
 444
 445         /*  Read the data  */
 446         data = ixgb_shift_in_bits(hw);
 447
 448         /*  End this read operation  */
 449         ixgb_standby_eeprom(hw);
 450
 451         return data;
 452 }
 453
 454 /******************************************************************************
 455  * Reads eeprom and stores data in shared structure.
 456  * Validates eeprom checksum and eeprom signature.
 457  *
 458  * hw - Struct containing variables accessed by shared code
 459  *
 460  * Returns:
 461  *      true: if eeprom read is successful
 462  *      false: otherwise.
 463  *****************************************************************************/
 464 bool
 465 ixgb_get_eeprom_data(struct ixgb_hw *hw)
 466 {
 467         u16 i;
 468         u16 checksum = 0;
 469         struct ixgb_ee_map_type *ee_map;
 470
 471         ENTER();
 472
 473         ee_map = (struct ixgb_ee_map_type *)hw->eeprom;
 474
 475         pr_debug("Reading eeprom data\n");
 476         for (i = 0; i < IXGB_EEPROM_SIZE ; i++) {
 477                 u16 ee_data;
 478                 ee_data = ixgb_read_eeprom(hw, i);
 479                 checksum += ee_data;
 480                 hw->eeprom[i] = cpu_to_le16(ee_data);
 481         }
 482
 483         if (checksum != (u16) EEPROM_SUM) {
 484                 pr_debug("Checksum invalid\n");
 485                 /* clear the init_ctrl_reg_1 to signify that the cache is
 486                  * invalidated */
 487                 ee_map->init_ctrl_reg_1 = cpu_to_le16(EEPROM_ICW1_SIGNATURE_CLEAR);
 488                 return false;
 489         }
 490
 491         if ((ee_map->init_ctrl_reg_1 & cpu_to_le16(EEPROM_ICW1_SIGNATURE_MASK))
 492                  != cpu_to_le16(EEPROM_ICW1_SIGNATURE_VALID)) {
 493                 pr_debug("Signature invalid\n");
 494                 return false;
 495         }
 496
 497         return true;
 498 }
 499
 500 /******************************************************************************
 501  * Local function to check if the eeprom signature is good
 502  * If the eeprom signature is good, calls ixgb)get_eeprom_data.
 503  *
 504  * hw - Struct containing variables accessed by shared code
 505  *
 506  * Returns:
 507  *      true: eeprom signature was good and the eeprom read was successful
 508  *      false: otherwise.
 509  ******************************************************************************/
 510 static bool
 511 ixgb_check_and_get_eeprom_data (struct ixgb_hw* hw)
 512 {
 513         struct ixgb_ee_map_type *ee_map = (struct ixgb_ee_map_type *)hw->eeprom;
 514
 515         if ((ee_map->init_ctrl_reg_1 & cpu_to_le16(EEPROM_ICW1_SIGNATURE_MASK))
 516             == cpu_to_le16(EEPROM_ICW1_SIGNATURE_VALID)) {
 517                 return true;
 518         } else {
 519                 return ixgb_get_eeprom_data(hw);
 520         }
 521 }
 522
 523 /******************************************************************************
 524  * return a word from the eeprom
 525  *
 526  * hw - Struct containing variables accessed by shared code
 527  * index - Offset of eeprom word
 528  *
 529  * Returns:
 530  *          Word at indexed offset in eeprom, if valid, 0 otherwise.
 531  ******************************************************************************/
 532 __le16
 533 ixgb_get_eeprom_word(struct ixgb_hw *hw, u16 index)
 534 {
 535
 536         if ((index < IXGB_EEPROM_SIZE) &&
 537                 (ixgb_check_and_get_eeprom_data(hw) == true)) {
 538            return hw->eeprom[index];
 539         }
 540
 541         return 0;
 542 }
 543
 544 /******************************************************************************
 545  * return the mac address from EEPROM
 546  *
 547  * hw       - Struct containing variables accessed by shared code
 548  * mac_addr - Ethernet Address if EEPROM contents are valid, 0 otherwise
 549  *
 550  * Returns: None.
 551  ******************************************************************************/
 552 void
 553 ixgb_get_ee_mac_addr(struct ixgb_hw *hw,
 554                         u8 *mac_addr)
 555 {
 556         int i;
 557         struct ixgb_ee_map_type *ee_map = (struct ixgb_ee_map_type *)hw->eeprom;
 558
 559         ENTER();
 560
 561         if (ixgb_check_and_get_eeprom_data(hw) == true) {
 562                 for (i = 0; i < ETH_ALEN; i++) {
 563                         mac_addr[i] = ee_map->mac_addr[i];
 564                 }
 565                 pr_debug("eeprom mac address = %pM\n", mac_addr);
 566         }
 567 }
 568
 569
 570 /******************************************************************************
 571  * return the Printed Board Assembly number from EEPROM
 572  *
 573  * hw - Struct containing variables accessed by shared code
 574  *
 575  * Returns:
 576  *          PBA number if EEPROM contents are valid, 0 otherwise
 577  ******************************************************************************/
 578 u32
 579 ixgb_get_ee_pba_number(struct ixgb_hw *hw)
 580 {
 581         if (ixgb_check_and_get_eeprom_data(hw) == true)
 582                 return le16_to_cpu(hw->eeprom[EEPROM_PBA_1_2_REG])
 583                         | (le16_to_cpu(hw->eeprom[EEPROM_PBA_3_4_REG])<<16);
 584
 585         return 0;
 586 }
 587
 588
 589 /******************************************************************************
 590  * return the Device Id from EEPROM
 591  *
 592  * hw - Struct containing variables accessed by shared code
 593  *
 594  * Returns:
 595  *          Device Id if EEPROM contents are valid, 0 otherwise
 596  ******************************************************************************/
 597 u16
 598 ixgb_get_ee_device_id(struct ixgb_hw *hw)
 599 {
 600         struct ixgb_ee_map_type *ee_map = (struct ixgb_ee_map_type *)hw->eeprom;
 601
 602         if (ixgb_check_and_get_eeprom_data(hw) == true)
 603                 return le16_to_cpu(ee_map->device_id);
 604
 605         return 0;
 606 }
 607