1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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 __FBSDID("$FreeBSD$");
33 #include <sys/param.h>
34 #include <sys/endian.h>
35 #include <sys/systm.h>
36 #include <sys/kernel.h>
37 #include <sys/limits.h>
38 #include <sys/bus.h>
39
40 #include <dev/iicbus/iicoc.h>
41
42 #include <mips/nlm/hal/haldefs.h>
43 #include <mips/nlm/hal/iomap.h>
44 #include <mips/nlm/hal/mips-extns.h> /* needed by board.h */
45
46 #include <mips/nlm/board.h>
47
48 /*
49 * We have to read the EEPROM in early boot (now only for MAC addr)
50 * but later for board information. Use simple polled mode driver
51 * for I2C
52 */
53 #define oc_read_reg(reg) nlm_read_reg(eeprom_i2c_base, reg)
54 #define oc_write_reg(reg, val) nlm_write_reg(eeprom_i2c_base, reg, val)
55
56 static uint64_t eeprom_i2c_base;
57
58 static int
oc_wait_on_status(uint8_t bit)59 oc_wait_on_status(uint8_t bit)
60 {
61 int tries = I2C_TIMEOUT;
62 uint8_t status;
63
64 do {
65 status = oc_read_reg(OC_I2C_STATUS_REG);
66 } while ((status & bit) != 0 && --tries > 0);
67
68 return (tries == 0 ? -1: 0);
69 }
70
71 static int
oc_rd_cmd(uint8_t cmd)72 oc_rd_cmd(uint8_t cmd)
73 {
74 uint8_t data;
75
76 oc_write_reg(OC_I2C_CMD_REG, cmd);
77 if (oc_wait_on_status(OC_STATUS_TIP) < 0)
78 return (-1);
79
80 data = oc_read_reg(OC_I2C_DATA_REG);
81 return (data);
82 }
83
84 static int
oc_wr_cmd(uint8_t data,uint8_t cmd)85 oc_wr_cmd(uint8_t data, uint8_t cmd)
86 {
87 oc_write_reg(OC_I2C_DATA_REG, data);
88 oc_write_reg(OC_I2C_CMD_REG, cmd);
89
90 if (oc_wait_on_status(OC_STATUS_TIP) < 0)
91 return (-1);
92 return (0);
93 }
94
95 int
nlm_board_eeprom_read(int node,int bus,int addr,int offs,uint8_t * buf,int sz)96 nlm_board_eeprom_read(int node, int bus, int addr, int offs, uint8_t *buf,
97 int sz)
98 {
99 int rd, i;
100 char *err = NULL;
101
102 eeprom_i2c_base = nlm_pcicfg_base(XLP_IO_I2C_OFFSET(node, bus)) +
103 XLP_IO_PCI_HDRSZ;
104
105 if (oc_wait_on_status(OC_STATUS_BUSY) < 0) {
106 err = "Not idle";
107 goto err_exit;
108 }
109
110 /* write start */
111 if (oc_wr_cmd(addr, OC_COMMAND_START)) {
112 err = "I2C write start failed.";
113 goto err_exit;
114 }
115
116 if (oc_read_reg(OC_I2C_STATUS_REG) & OC_STATUS_NACK) {
117 err = "No ack after start";
118 goto err_exit_stop;
119 }
120
121 if (oc_read_reg(OC_I2C_STATUS_REG) & OC_STATUS_AL) {
122 err = "I2C Bus Arbitration Lost";
123 goto err_exit_stop;
124 }
125
126 /* Write offset */
127 if (oc_wr_cmd(offs, OC_COMMAND_WRITE)) {
128 err = "I2C write slave offset failed.";
129 goto err_exit_stop;
130 }
131
132 if (oc_read_reg(OC_I2C_STATUS_REG) & OC_STATUS_NACK) {
133 err = "No ack after write";
134 goto err_exit_stop;
135 }
136
137 /* read start */
138 if (oc_wr_cmd(addr | 1, OC_COMMAND_START)) {
139 err = "I2C read start failed.";
140 goto err_exit_stop;
141 }
142
143 if (oc_read_reg(OC_I2C_STATUS_REG) & OC_STATUS_NACK) {
144 err = "No ack after read start";
145 goto err_exit_stop;
146 }
147
148 for (i = 0; i < sz - 1; i++) {
149 if ((rd = oc_rd_cmd(OC_COMMAND_READ)) < 0) {
150 err = "I2C read data byte failed.";
151 goto err_exit_stop;
152 }
153 buf[i] = rd;
154 }
155
156 /* last byte */
157 if ((rd = oc_rd_cmd(OC_COMMAND_RDNACK)) < 0) {
158 err = "I2C read last data byte failed.";
159 goto err_exit_stop;
160 }
161 buf[sz - 1] = rd;
162
163 err_exit_stop:
164 oc_write_reg(OC_I2C_CMD_REG, OC_COMMAND_STOP);
165 if (oc_wait_on_status(OC_STATUS_BUSY) < 0)
166 printf("%s: stop failed", __func__);
167
168 err_exit:
169 if (err) {
170 printf("%s: Failed (%s)\n", __func__, err);
171 return (-1);
172 }
173 return (0);
174 }
175