board/compulab/common/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 #ifndef CONFIG_SYS_I2C_EEPROM_ADDR
  14 # define CONFIG_SYS_I2C_EEPROM_ADDR     0x50
  15 # define CONFIG_SYS_I2C_EEPROM_ADDR_LEN 1
  16 #endif
  17
  18 #define EEPROM_LAYOUT_VER_OFFSET        44
  19 #define BOARD_SERIAL_OFFSET             20
  20 #define BOARD_SERIAL_OFFSET_LEGACY      8
  21 #define BOARD_REV_OFFSET                0
  22 #define BOARD_REV_OFFSET_LEGACY         6
  23 #define BOARD_REV_SIZE                  2
  24 #define MAC_ADDR_OFFSET                 4
  25 #define MAC_ADDR_OFFSET_LEGACY          0
  26
  27 #define LAYOUT_INVALID  0
  28 #define LAYOUT_LEGACY   0xff
  29
  30 static int cl_eeprom_layout; /* Implicitly LAYOUT_INVALID */
  31
  32 static int cl_eeprom_read(uint offset, uchar *buf, int len)
  33 {
  34         return i2c_read(CONFIG_SYS_I2C_EEPROM_ADDR, offset,
  35                         CONFIG_SYS_I2C_EEPROM_ADDR_LEN, buf, len);
  36 }
  37
  38 static int cl_eeprom_setup_layout(void)
  39 {
  40         int res;
  41
  42         if (cl_eeprom_layout != LAYOUT_INVALID)
  43                 return 0;
  44
  45         res = cl_eeprom_read(EEPROM_LAYOUT_VER_OFFSET,
  46                              (uchar *)&cl_eeprom_layout, 1);
  47         if (res) {
  48                 cl_eeprom_layout = LAYOUT_INVALID;
  49                 return res;
  50         }
  51
  52         if (cl_eeprom_layout == 0 || cl_eeprom_layout >= 0x20)
  53                 cl_eeprom_layout = LAYOUT_LEGACY;
  54
  55         return 0;
  56 }
  57
  58 void get_board_serial(struct tag_serialnr *serialnr)
  59 {
  60         u32 serial[2];
  61         uint offset;
  62
  63         memset(serialnr, 0, sizeof(*serialnr));
  64
  65         if (cl_eeprom_setup_layout())
  66                 return;
  67
  68         offset = (cl_eeprom_layout != LAYOUT_LEGACY) ?
  69                 BOARD_SERIAL_OFFSET : BOARD_SERIAL_OFFSET_LEGACY;
  70
  71         if (cl_eeprom_read(offset, (uchar *)serial, 8))
  72                 return;
  73
  74         if (serial[0] != 0xffffffff && serial[1] != 0xffffffff) {
  75                 serialnr->low = serial[0];
  76                 serialnr->high = serial[1];
  77         }
  78 }
  79
  80 /*
  81  * Routine: cl_eeprom_read_mac_addr
  82  * Description: read mac address and store it in buf.
  83  */
  84 int cl_eeprom_read_mac_addr(uchar *buf)
  85 {
  86         uint offset;
  87
  88         if (cl_eeprom_setup_layout())
  89                 return 0;
  90
  91         offset = (cl_eeprom_layout != LAYOUT_LEGACY) ?
  92                         MAC_ADDR_OFFSET : MAC_ADDR_OFFSET_LEGACY;
  93
  94         return cl_eeprom_read(offset, buf, 6);
  95 }
  96
  97 /*
  98  * Routine: cl_eeprom_get_board_rev
  99  * Description: read system revision from eeprom
 100  */
 101 u32 cl_eeprom_get_board_rev(void)
 102 {
 103         u32 rev = 0;
 104         char str[5]; /* Legacy representation can contain at most 4 digits */
 105         uint offset = BOARD_REV_OFFSET_LEGACY;
 106
 107         if (cl_eeprom_setup_layout())
 108                 return 0;
 109
 110         if (cl_eeprom_layout != LAYOUT_LEGACY)
 111                 offset = BOARD_REV_OFFSET;
 112
 113         if (cl_eeprom_read(offset, (uchar *)&rev, BOARD_REV_SIZE))
 114                 return 0;
 115
 116         /*
 117          * Convert legacy syntactic representation to semantic
 118          * representation. i.e. for rev 1.00: 0x100 --> 0x64
 119          */
 120         if (cl_eeprom_layout == LAYOUT_LEGACY) {
 121                 sprintf(str, "%x", rev);
 122                 rev = simple_strtoul(str, NULL, 10);
 123         }
 124
 125         return rev;
 126 };