xref: /openbmc/u-boot/board/compulab/common/eeprom.c (revision 70ad375e)
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 cl_eeprom_layout; /* Implicitly LAYOUT_INVALID */
26 
27 static int cl_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 cl_eeprom_setup_layout(void)
34 {
35 	int res;
36 
37 	if (cl_eeprom_layout != LAYOUT_INVALID)
38 		return 0;
39 
40 	res = cl_eeprom_read(EEPROM_LAYOUT_VER_OFFSET,
41 			     (uchar *)&cl_eeprom_layout, 1);
42 	if (res) {
43 		cl_eeprom_layout = LAYOUT_INVALID;
44 		return res;
45 	}
46 
47 	if (cl_eeprom_layout == 0 || cl_eeprom_layout >= 0x20)
48 		cl_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 
60 	if (cl_eeprom_setup_layout())
61 		return;
62 
63 	offset = (cl_eeprom_layout != LAYOUT_LEGACY) ?
64 		BOARD_SERIAL_OFFSET : BOARD_SERIAL_OFFSET_LEGACY;
65 
66 	if (cl_eeprom_read(offset, (uchar *)serial, 8))
67 		return;
68 
69 	if (serial[0] != 0xffffffff && serial[1] != 0xffffffff) {
70 		serialnr->low = serial[0];
71 		serialnr->high = serial[1];
72 	}
73 }
74 
75 /*
76  * Routine: cl_eeprom_read_mac_addr
77  * Description: read mac address and store it in buf.
78  */
79 int cl_eeprom_read_mac_addr(uchar *buf)
80 {
81 	uint offset;
82 
83 	if (cl_eeprom_setup_layout())
84 		return 0;
85 
86 	offset = (cl_eeprom_layout != LAYOUT_LEGACY) ?
87 			MAC_ADDR_OFFSET : MAC_ADDR_OFFSET_LEGACY;
88 
89 	return cl_eeprom_read(offset, buf, 6);
90 }
91 
92 /*
93  * Routine: cl_eeprom_get_board_rev
94  * Description: read system revision from eeprom
95  */
96 u32 cl_eeprom_get_board_rev(void)
97 {
98 	u32 rev = 0;
99 	char str[5]; /* Legacy representation can contain at most 4 digits */
100 	uint offset = BOARD_REV_OFFSET_LEGACY;
101 
102 	if (cl_eeprom_setup_layout())
103 		return 0;
104 
105 	if (cl_eeprom_layout != LAYOUT_LEGACY)
106 		offset = BOARD_REV_OFFSET;
107 
108 	if (cl_eeprom_read(offset, (uchar *)&rev, BOARD_REV_SIZE))
109 		return 0;
110 
111 	/*
112 	 * Convert legacy syntactic representation to semantic
113 	 * representation. i.e. for rev 1.00: 0x100 --> 0x64
114 	 */
115 	if (cl_eeprom_layout == LAYOUT_LEGACY) {
116 		sprintf(str, "%x", rev);
117 		rev = simple_strtoul(str, NULL, 10);
118 	}
119 
120 	return rev;
121 };
122