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
|
/*-
* Copyright (C) 2008 MARVELL INTERNATIONAL LTD.
* All rights reserved.
*
* Developed by Semihalf.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of MARVELL nor the names of contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/*
* Driver for the TWSI (aka I2C, aka IIC) bus controller found on Marvell
* and Allwinner SoCs. Supports master operation only, and works in polling mode.
*
* Calls to DELAY() are needed per Application Note AN-179 "TWSI Software
* Guidelines for Discovery(TM), Horizon (TM) and Feroceon(TM) Devices".
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/resource.h>
#include <machine/_inttypes.h>
#include <machine/bus.h>
#include <machine/resource.h>
#include <sys/rman.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <dev/iicbus/iiconf.h>
#include <dev/iicbus/iicbus.h>
#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/ofw_bus_subr.h>
#ifdef EXT_RESOURCES
#include <dev/extres/clk/clk.h>
#endif
#include <arm/mv/mvreg.h>
#include <arm/mv/mvvar.h>
#include <dev/iicbus/twsi/twsi.h>
#include "iicbus_if.h"
#define MV_TWSI_NAME "twsi"
#define IICBUS_DEVNAME "iicbus"
#define TWSI_ADDR 0x00
#define TWSI_DATA 0x04
#define TWSI_CNTR 0x08
#define TWSI_XADDR 0x10
#define TWSI_STAT 0x0c
#define TWSI_BAUD_RATE 0x0c
#define TWSI_SRST 0x1c
#define TWSI_BAUD_RATE_RAW(C,M,N) ((C)/((10*(M+1))<<(N+1)))
#define TWSI_BAUD_RATE_SLOW 50000 /* 50kHz */
#define TWSI_BAUD_RATE_FAST 100000 /* 100kHz */
#define TWSI_DEBUG
#undef TWSI_DEBUG
#ifdef TWSI_DEBUG
#define debugf(fmt, args...) do { printf("%s(): ", __func__); printf(fmt,##args); } while (0)
#else
#define debugf(fmt, args...)
#endif
static phandle_t mv_twsi_get_node(device_t, device_t);
static int mv_twsi_probe(device_t);
static int mv_twsi_attach(device_t);
static struct ofw_compat_data compat_data[] = {
{ "mrvl,twsi", true },
{ "marvell,mv64xxx-i2c", true },
{ "marvell,mv78230-i2c", true },
{ NULL, false }
};
static device_method_t mv_twsi_methods[] = {
/* device interface */
DEVMETHOD(device_probe, mv_twsi_probe),
DEVMETHOD(device_attach, mv_twsi_attach),
/* ofw_bus interface */
DEVMETHOD(ofw_bus_get_node, mv_twsi_get_node),
DEVMETHOD_END
};
DEFINE_CLASS_1(twsi, mv_twsi_driver, mv_twsi_methods,
sizeof(struct twsi_softc), twsi_driver);
static devclass_t mv_twsi_devclass;
DRIVER_MODULE(twsi, simplebus, mv_twsi_driver, mv_twsi_devclass, 0, 0);
DRIVER_MODULE(iicbus, twsi, iicbus_driver, iicbus_devclass, 0, 0);
MODULE_DEPEND(twsi, iicbus, 1, 1, 1);
SIMPLEBUS_PNP_INFO(compat_data);
static phandle_t
mv_twsi_get_node(device_t bus, device_t dev)
{
/* Used by ofw_iicbus. */
return (ofw_bus_get_node(bus));
}
static int
mv_twsi_probe(device_t dev)
{
struct twsi_softc *sc;
sc = device_get_softc(dev);
if (!ofw_bus_status_okay(dev))
return (ENXIO);
if (!ofw_bus_search_compatible(dev, compat_data)->ocd_data)
return (ENXIO);
device_set_desc(dev, "Marvell Integrated I2C Bus Controller");
return (BUS_PROBE_DEFAULT);
}
#define ABSSUB(a,b) (((a) > (b)) ? (a) - (b) : (b) - (a))
static void
mv_twsi_cal_baud_rate(struct twsi_softc *sc, const uint32_t target,
struct twsi_baud_rate *rate)
{
uint64_t clk;
uint32_t cur, diff, diff0;
int m, n, m0, n0;
/* Calculate baud rate. */
m0 = n0 = 4; /* Default values on reset */
diff0 = 0xffffffff;
#ifdef __aarch64__
clk_get_freq(sc->clk_core, &clk);
#else
clk = get_tclk();
#endif
for (n = 0; n < 8; n++) {
for (m = 0; m < 16; m++) {
cur = TWSI_BAUD_RATE_RAW(clk,m,n);
diff = ABSSUB(target, cur);
if (diff < diff0) {
m0 = m;
n0 = n;
diff0 = diff;
}
}
}
rate->raw = TWSI_BAUD_RATE_RAW(clk, m0, n0);
rate->param = TWSI_BAUD_RATE_PARAM(m0, n0);
rate->m = m0;
rate->n = n0;
}
static int
mv_twsi_attach(device_t dev)
{
struct twsi_softc *sc;
#ifdef __aarch64__
int error;
#endif
sc = device_get_softc(dev);
sc->dev = dev;
#ifdef __aarch64__
/* Activate clock */
error = clk_get_by_ofw_index(dev, 0, 0, &sc->clk_core);
if (error != 0) {
device_printf(dev, "could not find core clock\n");
return (error);
}
error = clk_enable(sc->clk_core);
if (error != 0) {
device_printf(dev, "could not enable core clock\n");
return (error);
}
if (clk_get_by_ofw_index(dev, 0, 1, &sc->clk_reg) == 0) {
error = clk_enable(sc->clk_reg);
if (error != 0) {
device_printf(dev, "could not enable core clock\n");
return (error);
}
}
#endif
mv_twsi_cal_baud_rate(sc, TWSI_BAUD_RATE_SLOW, &sc->baud_rate[IIC_SLOW]);
mv_twsi_cal_baud_rate(sc, TWSI_BAUD_RATE_FAST, &sc->baud_rate[IIC_FAST]);
if (bootverbose)
device_printf(dev, "calculated baud rates are:\n"
" %" PRIu32 " kHz (M=%d, N=%d) for slow,\n"
" %" PRIu32 " kHz (M=%d, N=%d) for fast.\n",
sc->baud_rate[IIC_SLOW].raw / 1000,
sc->baud_rate[IIC_SLOW].m,
sc->baud_rate[IIC_SLOW].n,
sc->baud_rate[IIC_FAST].raw / 1000,
sc->baud_rate[IIC_FAST].m,
sc->baud_rate[IIC_FAST].n);
sc->reg_data = TWSI_DATA;
sc->reg_slave_addr = TWSI_ADDR;
sc->reg_slave_ext_addr = TWSI_XADDR;
sc->reg_control = TWSI_CNTR;
sc->reg_status = TWSI_STAT;
sc->reg_baud_rate = TWSI_BAUD_RATE;
sc->reg_soft_reset = TWSI_SRST;
return (twsi_attach(dev));
}
|
