1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
|
/*
* Cavium ThunderX i2c driver.
*
* Copyright (C) 2015,2016 Cavium Inc.
* Authors: Fred Martin <fmartin@caviumnetworks.com>
* Jan Glauber <jglauber@cavium.com>
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*/
#include <linux/acpi.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/i2c.h>
#include <linux/i2c-smbus.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of_irq.h>
#include <linux/pci.h>
#include "i2c-octeon-core.h"
#define DRV_NAME "i2c-thunderx"
#define PCI_DEVICE_ID_THUNDER_TWSI 0xa012
#define SYS_FREQ_DEFAULT 700000000
#define TWSI_INT_ENA_W1C 0x1028
#define TWSI_INT_ENA_W1S 0x1030
/*
* Enable the CORE interrupt.
* The interrupt will be asserted when there is non-STAT_IDLE state in the
* SW_TWSI_EOP_TWSI_STAT register.
*/
static void thunder_i2c_int_enable(struct octeon_i2c *i2c)
{
octeon_i2c_writeq_flush(TWSI_INT_CORE_INT,
i2c->twsi_base + TWSI_INT_ENA_W1S);
}
/*
* Disable the CORE interrupt.
*/
static void thunder_i2c_int_disable(struct octeon_i2c *i2c)
{
octeon_i2c_writeq_flush(TWSI_INT_CORE_INT,
i2c->twsi_base + TWSI_INT_ENA_W1C);
}
static void thunder_i2c_hlc_int_enable(struct octeon_i2c *i2c)
{
octeon_i2c_writeq_flush(TWSI_INT_ST_INT | TWSI_INT_TS_INT,
i2c->twsi_base + TWSI_INT_ENA_W1S);
}
static void thunder_i2c_hlc_int_disable(struct octeon_i2c *i2c)
{
octeon_i2c_writeq_flush(TWSI_INT_ST_INT | TWSI_INT_TS_INT,
i2c->twsi_base + TWSI_INT_ENA_W1C);
}
static u32 thunderx_i2c_functionality(struct i2c_adapter *adap)
{
return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK) |
I2C_FUNC_SMBUS_READ_BLOCK_DATA | I2C_SMBUS_BLOCK_PROC_CALL;
}
static const struct i2c_algorithm thunderx_i2c_algo = {
.master_xfer = octeon_i2c_xfer,
.functionality = thunderx_i2c_functionality,
};
static const struct i2c_adapter thunderx_i2c_ops = {
.owner = THIS_MODULE,
.name = "ThunderX adapter",
.algo = &thunderx_i2c_algo,
};
static void thunder_i2c_clock_enable(struct device *dev, struct octeon_i2c *i2c)
{
int ret;
if (acpi_disabled) {
/* DT */
i2c->clk = clk_get(dev, NULL);
if (IS_ERR(i2c->clk)) {
i2c->clk = NULL;
goto skip;
}
ret = clk_prepare_enable(i2c->clk);
if (ret)
goto skip;
i2c->sys_freq = clk_get_rate(i2c->clk);
} else {
/* ACPI */
device_property_read_u32(dev, "sclk", &i2c->sys_freq);
}
skip:
if (!i2c->sys_freq)
i2c->sys_freq = SYS_FREQ_DEFAULT;
}
static void thunder_i2c_clock_disable(struct device *dev, struct clk *clk)
{
if (!clk)
return;
clk_disable_unprepare(clk);
clk_put(clk);
}
static int thunder_i2c_smbus_setup_of(struct octeon_i2c *i2c,
struct device_node *node)
{
struct i2c_client *ara;
if (!node)
return -EINVAL;
i2c->alert_data.irq = irq_of_parse_and_map(node, 0);
if (!i2c->alert_data.irq)
return -EINVAL;
ara = i2c_new_smbus_alert_device(&i2c->adap, &i2c->alert_data);
if (IS_ERR(ara))
return PTR_ERR(ara);
i2c->ara = ara;
return 0;
}
static int thunder_i2c_smbus_setup(struct octeon_i2c *i2c,
struct device_node *node)
{
/* TODO: ACPI support */
if (!acpi_disabled)
return -EOPNOTSUPP;
return thunder_i2c_smbus_setup_of(i2c, node);
}
static void thunder_i2c_smbus_remove(struct octeon_i2c *i2c)
{
i2c_unregister_device(i2c->ara);
}
static int thunder_i2c_probe_pci(struct pci_dev *pdev,
const struct pci_device_id *ent)
{
struct device *dev = &pdev->dev;
struct octeon_i2c *i2c;
int ret;
i2c = devm_kzalloc(dev, sizeof(*i2c), GFP_KERNEL);
if (!i2c)
return -ENOMEM;
i2c->roff.sw_twsi = 0x1000;
i2c->roff.twsi_int = 0x1010;
i2c->roff.sw_twsi_ext = 0x1018;
i2c->dev = dev;
pci_set_drvdata(pdev, i2c);
ret = pcim_enable_device(pdev);
if (ret)
return ret;
ret = pci_request_regions(pdev, DRV_NAME);
if (ret)
return ret;
i2c->twsi_base = pcim_iomap(pdev, 0, pci_resource_len(pdev, 0));
if (!i2c->twsi_base)
return -EINVAL;
thunder_i2c_clock_enable(dev, i2c);
ret = device_property_read_u32(dev, "clock-frequency", &i2c->twsi_freq);
if (ret)
i2c->twsi_freq = I2C_MAX_STANDARD_MODE_FREQ;
init_waitqueue_head(&i2c->queue);
i2c->int_enable = thunder_i2c_int_enable;
i2c->int_disable = thunder_i2c_int_disable;
i2c->hlc_int_enable = thunder_i2c_hlc_int_enable;
i2c->hlc_int_disable = thunder_i2c_hlc_int_disable;
ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSIX);
if (ret < 0)
goto error;
ret = devm_request_irq(dev, pci_irq_vector(pdev, 0), octeon_i2c_isr, 0,
DRV_NAME, i2c);
if (ret)
goto error;
ret = octeon_i2c_init_lowlevel(i2c);
if (ret)
goto error;
octeon_i2c_set_clock(i2c);
i2c->adap = thunderx_i2c_ops;
i2c->adap.retries = 5;
i2c->adap.class = I2C_CLASS_HWMON;
i2c->adap.bus_recovery_info = &octeon_i2c_recovery_info;
i2c->adap.dev.parent = dev;
i2c->adap.dev.of_node = pdev->dev.of_node;
snprintf(i2c->adap.name, sizeof(i2c->adap.name),
"Cavium ThunderX i2c adapter at %s", dev_name(dev));
i2c_set_adapdata(&i2c->adap, i2c);
ret = i2c_add_adapter(&i2c->adap);
if (ret)
goto error;
dev_info(i2c->dev, "Probed. Set system clock to %u\n", i2c->sys_freq);
ret = thunder_i2c_smbus_setup(i2c, pdev->dev.of_node);
if (ret)
dev_info(dev, "SMBUS alert not active on this bus\n");
return 0;
error:
thunder_i2c_clock_disable(dev, i2c->clk);
return ret;
}
static void thunder_i2c_remove_pci(struct pci_dev *pdev)
{
struct octeon_i2c *i2c = pci_get_drvdata(pdev);
thunder_i2c_smbus_remove(i2c);
thunder_i2c_clock_disable(&pdev->dev, i2c->clk);
i2c_del_adapter(&i2c->adap);
}
static const struct pci_device_id thunder_i2c_pci_id_table[] = {
{ PCI_DEVICE(PCI_VENDOR_ID_CAVIUM, PCI_DEVICE_ID_THUNDER_TWSI) },
{ 0, }
};
MODULE_DEVICE_TABLE(pci, thunder_i2c_pci_id_table);
static struct pci_driver thunder_i2c_pci_driver = {
.name = DRV_NAME,
.id_table = thunder_i2c_pci_id_table,
.probe = thunder_i2c_probe_pci,
.remove = thunder_i2c_remove_pci,
};
module_pci_driver(thunder_i2c_pci_driver);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Fred Martin <fmartin@caviumnetworks.com>");
MODULE_DESCRIPTION("I2C-Bus adapter for Cavium ThunderX SOC");
|
