board/compulab/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  * SPDX-License-Identifier:     GPL-2.0+
   8  */
   9
  10 #include <common.h>
  11 #include <i2c.h>
  12
  13 #define EEPROM_LAYOUT_VER_OFFSET        44
  14 #define BOARD_SERIAL_OFFSET             20
  15 #define BOARD_SERIAL_OFFSET_LEGACY      8
  16 #define BOARD_REV_OFFSET                0
  17 #define BOARD_REV_OFFSET_LEGACY         6
  18 #define BOARD_REV_SIZE                  2
  19 #define MAC_ADDR_OFFSET                 4
  20 #define MAC_ADDR_OFFSET_LEGACY          0
  21
  22 #define LAYOUT_INVALID  0
  23 #define LAYOUT_LEGACY   0xff
  24
  25 static int eeprom_layout; /* Implicitly LAYOUT_INVALID */
  26
  27 static int cm_t3x_eeprom_read(uint offset, uchar *buf, int len)
  28 {
  29         return i2c_read(CONFIG_SYS_I2C_EEPROM_ADDR, offset,
  30                         CONFIG_SYS_I2C_EEPROM_ADDR_LEN, buf, len);
  31 }
  32
  33 static int eeprom_setup_layout(void)
  34 {
  35         int res;
  36
  37         if (eeprom_layout != LAYOUT_INVALID)
  38                 return 0;
  39
  40         res = cm_t3x_eeprom_read(EEPROM_LAYOUT_VER_OFFSET,
  41                                                 (uchar *)&eeprom_layout, 1);
  42         if (res) {
  43                 eeprom_layout = LAYOUT_INVALID;
  44                 return res;
  45         }
  46
  47         if (eeprom_layout == 0 || eeprom_layout >= 0x20)
  48                 eeprom_layout = LAYOUT_LEGACY;
  49
  50         return 0;
  51 }
  52
  53 void get_board_serial(struct tag_serialnr *serialnr)
  54 {
  55         u32 serial[2];
  56         uint offset;
  57
  58         memset(serialnr, 0, sizeof(*serialnr));
  59         if (eeprom_setup_layout())
  60                 return;
  61
  62         offset = (eeprom_layout != LAYOUT_LEGACY) ?
  63                         BOARD_SERIAL_OFFSET : BOARD_SERIAL_OFFSET_LEGACY;
  64         if (cm_t3x_eeprom_read(offset, (uchar *)serial, 8))
  65                 return;
  66
  67         if (serial[0] != 0xffffffff && serial[1] != 0xffffffff) {
  68                 serialnr->low = serial[0];
  69                 serialnr->high = serial[1];
  70         }
  71 }
  72
  73 /*
  74  * Routine: cm_t3x_eeprom_read_mac_addr
  75  * Description: read mac address and store it in buf.
  76  */
  77 int cm_t3x_eeprom_read_mac_addr(uchar *buf)
  78 {
  79         uint offset;
  80
  81         if (eeprom_setup_layout())
  82                 return 0;
  83
  84         offset = (eeprom_layout != LAYOUT_LEGACY) ?
  85                         MAC_ADDR_OFFSET : MAC_ADDR_OFFSET_LEGACY;
  86         return cm_t3x_eeprom_read(offset, buf, 6);
  87 }
  88
  89 /*
  90  * Routine: cm_t3x_eeprom_get_board_rev
  91  * Description: read system revision from eeprom
  92  */
  93 u32 cm_t3x_eeprom_get_board_rev(void)
  94 {
  95         u32 rev = 0;
  96         char str[5]; /* Legacy representation can contain at most 4 digits */
  97         uint offset = BOARD_REV_OFFSET_LEGACY;
  98
  99         if (eeprom_setup_layout())
 100                 return 0;
 101
 102         if (eeprom_layout != LAYOUT_LEGACY)
 103                 offset = BOARD_REV_OFFSET;
 104
 105         if (cm_t3x_eeprom_read(offset, (uchar *)&rev, BOARD_REV_SIZE))
 106                 return 0;
 107
 108         /*
 109          * Convert legacy syntactic representation to semantic
 110          * representation. i.e. for rev 1.00: 0x100 --> 0x64
 111          */
 112         if (eeprom_layout == LAYOUT_LEGACY) {
 113                 sprintf(str, "%x", rev);
 114                 rev = simple_strtoul(str, NULL, 10);
 115         }
 116
 117         return rev;
 118 };