1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2003-2012 Broadcom Corporation
5 * All Rights Reserved
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 *
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in
15 * the documentation and/or other materials provided with the
16 * distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY BROADCOM ``AS IS'' AND ANY EXPRESS OR
19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
20 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL BROADCOM OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
25 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
26 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
27 * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
28 * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31 #include <sys/cdefs.h>
32 #include <sys/param.h>
33 #include <sys/endian.h>
34 #include <sys/systm.h>
35 #include <sys/kernel.h>
36 #include <sys/limits.h>
37 #include <sys/bus.h>
38
39 #include <dev/iicbus/iicoc.h>
40
41 #include <mips/nlm/hal/haldefs.h>
42 #include <mips/nlm/hal/iomap.h>
43 #include <mips/nlm/hal/mips-extns.h> /* needed by board.h */
44
45 #include <mips/nlm/board.h>
46
47 /*
48 * We have to read the EEPROM in early boot (now only for MAC addr)
49 * but later for board information. Use simple polled mode driver
50 * for I2C
51 */
52 #define oc_read_reg(reg) nlm_read_reg(eeprom_i2c_base, reg)
53 #define oc_write_reg(reg, val) nlm_write_reg(eeprom_i2c_base, reg, val)
54
55 static uint64_t eeprom_i2c_base;
56
57 static int
oc_wait_on_status(uint8_t bit)58 oc_wait_on_status(uint8_t bit)
59 {
60 int tries = I2C_TIMEOUT;
61 uint8_t status;
62
63 do {
64 status = oc_read_reg(OC_I2C_STATUS_REG);
65 } while ((status & bit) != 0 && --tries > 0);
66
67 return (tries == 0 ? -1: 0);
68 }
69
70 static int
oc_rd_cmd(uint8_t cmd)71 oc_rd_cmd(uint8_t cmd)
72 {
73 uint8_t data;
74
75 oc_write_reg(OC_I2C_CMD_REG, cmd);
76 if (oc_wait_on_status(OC_STATUS_TIP) < 0)
77 return (-1);
78
79 data = oc_read_reg(OC_I2C_DATA_REG);
80 return (data);
81 }
82
83 static int
oc_wr_cmd(uint8_t data,uint8_t cmd)84 oc_wr_cmd(uint8_t data, uint8_t cmd)
85 {
86 oc_write_reg(OC_I2C_DATA_REG, data);
87 oc_write_reg(OC_I2C_CMD_REG, cmd);
88
89 if (oc_wait_on_status(OC_STATUS_TIP) < 0)
90 return (-1);
91 return (0);
92 }
93
94 int
nlm_board_eeprom_read(int node,int bus,int addr,int offs,uint8_t * buf,int sz)95 nlm_board_eeprom_read(int node, int bus, int addr, int offs, uint8_t *buf,
96 int sz)
97 {
98 int rd, i;
99 char *err = NULL;
100
101 eeprom_i2c_base = nlm_pcicfg_base(XLP_IO_I2C_OFFSET(node, bus)) +
102 XLP_IO_PCI_HDRSZ;
103
104 if (oc_wait_on_status(OC_STATUS_BUSY) < 0) {
105 err = "Not idle";
106 goto err_exit;
107 }
108
109 /* write start */
110 if (oc_wr_cmd(addr, OC_COMMAND_START)) {
111 err = "I2C write start failed.";
112 goto err_exit;
113 }
114
115 if (oc_read_reg(OC_I2C_STATUS_REG) & OC_STATUS_NACK) {
116 err = "No ack after start";
117 goto err_exit_stop;
118 }
119
120 if (oc_read_reg(OC_I2C_STATUS_REG) & OC_STATUS_AL) {
121 err = "I2C Bus Arbitration Lost";
122 goto err_exit_stop;
123 }
124
125 /* Write offset */
126 if (oc_wr_cmd(offs, OC_COMMAND_WRITE)) {
127 err = "I2C write slave offset failed.";
128 goto err_exit_stop;
129 }
130
131 if (oc_read_reg(OC_I2C_STATUS_REG) & OC_STATUS_NACK) {
132 err = "No ack after write";
133 goto err_exit_stop;
134 }
135
136 /* read start */
137 if (oc_wr_cmd(addr | 1, OC_COMMAND_START)) {
138 err = "I2C read start failed.";
139 goto err_exit_stop;
140 }
141
142 if (oc_read_reg(OC_I2C_STATUS_REG) & OC_STATUS_NACK) {
143 err = "No ack after read start";
144 goto err_exit_stop;
145 }
146
147 for (i = 0; i < sz - 1; i++) {
148 if ((rd = oc_rd_cmd(OC_COMMAND_READ)) < 0) {
149 err = "I2C read data byte failed.";
150 goto err_exit_stop;
151 }
152 buf[i] = rd;
153 }
154
155 /* last byte */
156 if ((rd = oc_rd_cmd(OC_COMMAND_RDNACK)) < 0) {
157 err = "I2C read last data byte failed.";
158 goto err_exit_stop;
159 }
160 buf[sz - 1] = rd;
161
162 err_exit_stop:
163 oc_write_reg(OC_I2C_CMD_REG, OC_COMMAND_STOP);
164 if (oc_wait_on_status(OC_STATUS_BUSY) < 0)
165 printf("%s: stop failed", __func__);
166
167 err_exit:
168 if (err) {
169 printf("%s: Failed (%s)\n", __func__, err);
170 return (-1);
171 }
172 return (0);
173 }
174