board/cm_t35/eeprom.c

   1 /*
   2  * (C) Copyright 2011 CompuLab, Ltd. <www.compulab.co.il>
   3  *
   4  * Authors: Nikita Kiryanov <nikita@compulab.co.il>
   5  *          Igor Grinberg <grinberg@compulab.co.il>
   6  *
   7  * This program is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU General Public License as
   9  * published by the Free Software Foundation; either version 2 of
  10  * the License, or (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc.
  20  */
  21
  22 #include <common.h>
  23 #include <i2c.h>
  24
  25 #define EEPROM_LAYOUT_VER_OFFSET        44
  26 #define BOARD_SERIAL_OFFSET             20
  27 #define BOARD_SERIAL_OFFSET_LEGACY      8
  28 #define BOARD_REV_OFFSET                0
  29 #define BOARD_REV_OFFSET_LEGACY         6
  30 #define BOARD_REV_SIZE                  4
  31 #define BOARD_REV_SIZE_LEGACY           2
  32
  33 #define LAYOUT_INVALID  0
  34 #define LAYOUT_LEGACY   0xff
  35
  36 static int eeprom_layout; /* Implicitly LAYOUT_INVALID */
  37
  38 static int cm_t3x_eeprom_read(uint offset, uchar *buf, int len)
  39 {
  40         return i2c_read(CONFIG_SYS_I2C_EEPROM_ADDR, offset,
  41                         CONFIG_SYS_I2C_EEPROM_ADDR_LEN, buf, len);
  42 }
  43
  44 static int eeprom_setup_layout(void)
  45 {
  46         int res;
  47
  48         if (eeprom_layout != LAYOUT_INVALID)
  49                 return 0;
  50
  51         res = cm_t3x_eeprom_read(EEPROM_LAYOUT_VER_OFFSET,
  52                                                 (uchar *)&eeprom_layout, 1);
  53         if (res) {
  54                 eeprom_layout = LAYOUT_INVALID;
  55                 return res;
  56         }
  57
  58         if (eeprom_layout == 0 || eeprom_layout >= 0x20)
  59                 eeprom_layout = LAYOUT_LEGACY;
  60
  61         return 0;
  62 }
  63
  64 void get_board_serial(struct tag_serialnr *serialnr)
  65 {
  66         u32 serial[2];
  67         uint offset;
  68
  69         memset(serialnr, 0, sizeof(*serialnr));
  70         if (eeprom_setup_layout())
  71                 return;
  72
  73         offset = (eeprom_layout != LAYOUT_LEGACY) ?
  74                         BOARD_SERIAL_OFFSET : BOARD_SERIAL_OFFSET_LEGACY;
  75         if (cm_t3x_eeprom_read(offset, (uchar *)serial, 8))
  76                 return;
  77
  78         if (serial[0] != 0xffffffff && serial[1] != 0xffffffff) {
  79                 serialnr->low = serial[0];
  80                 serialnr->high = serial[1];
  81         }
  82 }
  83
  84 /*
  85  * Routine: get_board_rev
  86  * Description: read system revision
  87  */
  88 u32 get_board_rev(void)
  89 {
  90         u32 rev = 0;
  91         uint offset = BOARD_REV_OFFSET_LEGACY;
  92         int len = BOARD_REV_SIZE_LEGACY;
  93
  94         if (eeprom_setup_layout())
  95                 return 0;
  96
  97         if (eeprom_layout != LAYOUT_LEGACY) {
  98                 offset = BOARD_REV_OFFSET;
  99                 len = BOARD_REV_SIZE;
 100         }
 101
 102         if (cm_t3x_eeprom_read(offset, (uchar *)&rev, len))
 103                 return 0;
 104
 105         return rev;
 106 };