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
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
|
/****************************************************************************/
/*
* linux/arch/sh/boards/snapgear/rtc.c -- Secureedge5410 RTC code
*
* Copyright (C) 2002 David McCullough <davidm@snapgear.com>
* Copyright (C) 2003 Paul Mundt <lethal@linux-sh.org>
*
* The SecureEdge5410 can have one of 2 real time clocks, the SH
* built in version or the preferred external DS1302. Here we work out
* each to see what we have and then run with it.
*/
/****************************************************************************/
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/time.h>
#include <linux/rtc.h>
#include <linux/mc146818rtc.h>
#include <asm/io.h>
static int use_ds1302;
/****************************************************************************/
/*
* we need to implement a DS1302 driver here that can operate in
* conjunction with the builtin rtc driver which is already quite friendly
*/
/*****************************************************************************/
#define RTC_CMD_READ 0x81 /* Read command */
#define RTC_CMD_WRITE 0x80 /* Write command */
#define RTC_ADDR_YEAR 0x06 /* Address of year register */
#define RTC_ADDR_DAY 0x05 /* Address of day of week register */
#define RTC_ADDR_MON 0x04 /* Address of month register */
#define RTC_ADDR_DATE 0x03 /* Address of day of month register */
#define RTC_ADDR_HOUR 0x02 /* Address of hour register */
#define RTC_ADDR_MIN 0x01 /* Address of minute register */
#define RTC_ADDR_SEC 0x00 /* Address of second register */
#define RTC_RESET 0x1000
#define RTC_IODATA 0x0800
#define RTC_SCLK 0x0400
#define set_dirp(x)
#define get_dirp(x) 0
#define set_dp(x) SECUREEDGE_WRITE_IOPORT(x, 0x1c00)
#define get_dp(x) SECUREEDGE_READ_IOPORT()
static void ds1302_sendbits(unsigned int val)
{
int i;
for (i = 8; (i); i--, val >>= 1) {
set_dp((get_dp() & ~RTC_IODATA) | ((val & 0x1) ? RTC_IODATA : 0));
set_dp(get_dp() | RTC_SCLK); // clock high
set_dp(get_dp() & ~RTC_SCLK); // clock low
}
}
static unsigned int ds1302_recvbits(void)
{
unsigned int val;
int i;
for (i = 0, val = 0; (i < 8); i++) {
val |= (((get_dp() & RTC_IODATA) ? 1 : 0) << i);
set_dp(get_dp() | RTC_SCLK); // clock high
set_dp(get_dp() & ~RTC_SCLK); // clock low
}
return(val);
}
static unsigned int ds1302_readbyte(unsigned int addr)
{
unsigned int val;
unsigned long flags;
local_irq_save(flags);
set_dirp(get_dirp() | RTC_RESET | RTC_IODATA | RTC_SCLK);
set_dp(get_dp() & ~(RTC_RESET | RTC_IODATA | RTC_SCLK));
set_dp(get_dp() | RTC_RESET);
ds1302_sendbits(((addr & 0x3f) << 1) | RTC_CMD_READ);
set_dirp(get_dirp() & ~RTC_IODATA);
val = ds1302_recvbits();
set_dp(get_dp() & ~RTC_RESET);
local_irq_restore(flags);
return(val);
}
static void ds1302_writebyte(unsigned int addr, unsigned int val)
{
unsigned long flags;
local_irq_save(flags);
set_dirp(get_dirp() | RTC_RESET | RTC_IODATA | RTC_SCLK);
set_dp(get_dp() & ~(RTC_RESET | RTC_IODATA | RTC_SCLK));
set_dp(get_dp() | RTC_RESET);
ds1302_sendbits(((addr & 0x3f) << 1) | RTC_CMD_WRITE);
ds1302_sendbits(val);
set_dp(get_dp() & ~RTC_RESET);
local_irq_restore(flags);
}
static void ds1302_reset(void)
{
unsigned long flags;
/* Hardware dependant reset/init */
local_irq_save(flags);
set_dirp(get_dirp() | RTC_RESET | RTC_IODATA | RTC_SCLK);
set_dp(get_dp() & ~(RTC_RESET | RTC_IODATA | RTC_SCLK));
local_irq_restore(flags);
}
/*****************************************************************************/
static inline int bcd2int(int val)
{
return((((val & 0xf0) >> 4) * 10) + (val & 0xf));
}
static inline int int2bcd(int val)
{
return(((val / 10) << 4) + (val % 10));
}
/*****************************************************************************/
/*
* Write and Read some RAM in the DS1302, if it works assume it's there
* Otherwise use the SH4 internal RTC
*/
void snapgear_rtc_gettimeofday(struct timespec *);
int snapgear_rtc_settimeofday(const time_t);
void __init secureedge5410_rtc_init(void)
{
unsigned char *test = "snapgear";
int i;
ds1302_reset();
use_ds1302 = 1;
for (i = 0; test[i]; i++)
ds1302_writebyte(32 + i, test[i]);
for (i = 0; test[i]; i++)
if (ds1302_readbyte(32 + i) != test[i]) {
use_ds1302 = 0;
break;
}
if (use_ds1302) {
rtc_sh_get_time = snapgear_rtc_gettimeofday;
rtc_sh_set_time = snapgear_rtc_settimeofday;
}
printk("SnapGear RTC: using %s rtc.\n", use_ds1302 ? "ds1302" : "internal");
}
/****************************************************************************/
/*
* our generic interface that chooses the correct code to use
*/
void snapgear_rtc_gettimeofday(struct timespec *ts)
{
unsigned int sec, min, hr, day, mon, yr;
if (!use_ds1302)
return;
sec = bcd2int(ds1302_readbyte(RTC_ADDR_SEC));
min = bcd2int(ds1302_readbyte(RTC_ADDR_MIN));
hr = bcd2int(ds1302_readbyte(RTC_ADDR_HOUR));
day = bcd2int(ds1302_readbyte(RTC_ADDR_DATE));
mon = bcd2int(ds1302_readbyte(RTC_ADDR_MON));
yr = bcd2int(ds1302_readbyte(RTC_ADDR_YEAR));
bad_time:
if (yr > 99 || mon < 1 || mon > 12 || day > 31 || day < 1 ||
hr > 23 || min > 59 || sec > 59) {
printk(KERN_ERR
"SnapGear RTC: invalid value, resetting to 1 Jan 2000\n");
ds1302_writebyte(RTC_ADDR_MIN, min = 0);
ds1302_writebyte(RTC_ADDR_HOUR, hr = 0);
ds1302_writebyte(RTC_ADDR_DAY, 7);
ds1302_writebyte(RTC_ADDR_DATE, day = 1);
ds1302_writebyte(RTC_ADDR_MON, mon = 1);
ds1302_writebyte(RTC_ADDR_YEAR, yr = 0);
ds1302_writebyte(RTC_ADDR_SEC, sec = 0);
}
ts->tv_sec = mktime(2000 + yr, mon, day, hr, min, sec);
if (ts->tv_sec < 0) {
#if 0
printk("BAD TIME %d %d %d %d %d %d\n", yr, mon, day, hr, min, sec);
#endif
yr = 100;
goto bad_time;
}
ts->tv_nsec = 0;
}
int snapgear_rtc_settimeofday(const time_t secs)
{
int retval = 0;
int real_seconds, real_minutes, cmos_minutes;
unsigned long nowtime;
if (!use_ds1302)
return 0;
/*
* This is called direct from the kernel timer handling code.
* It is supposed to synchronize the kernel clock to the RTC.
*/
nowtime = secs;
/* STOP RTC */
ds1302_writebyte(RTC_ADDR_SEC, ds1302_readbyte(RTC_ADDR_SEC) | 0x80);
cmos_minutes = bcd2int(ds1302_readbyte(RTC_ADDR_MIN));
/*
* since we're only adjusting minutes and seconds,
* don't interfere with hour overflow. This avoids
* messing with unknown time zones but requires your
* RTC not to be off by more than 15 minutes
*/
real_seconds = nowtime % 60;
real_minutes = nowtime / 60;
if (((abs(real_minutes - cmos_minutes) + 15)/30) & 1)
real_minutes += 30; /* correct for half hour time zone */
real_minutes %= 60;
if (abs(real_minutes - cmos_minutes) < 30) {
ds1302_writebyte(RTC_ADDR_MIN, int2bcd(real_minutes));
ds1302_writebyte(RTC_ADDR_SEC, int2bcd(real_seconds));
} else {
printk(KERN_WARNING
"SnapGear RTC: can't update from %d to %d\n",
cmos_minutes, real_minutes);
retval = -1;
}
/* START RTC */
ds1302_writebyte(RTC_ADDR_SEC, ds1302_readbyte(RTC_ADDR_SEC) & ~0x80);
return(0);
}
unsigned char secureedge5410_cmos_read(int addr)
{
unsigned char val = 0;
if (!use_ds1302)
return(__CMOS_READ(addr, w));
switch(addr) {
case RTC_SECONDS: val = ds1302_readbyte(RTC_ADDR_SEC); break;
case RTC_SECONDS_ALARM: break;
case RTC_MINUTES: val = ds1302_readbyte(RTC_ADDR_MIN); break;
case RTC_MINUTES_ALARM: break;
case RTC_HOURS: val = ds1302_readbyte(RTC_ADDR_HOUR); break;
case RTC_HOURS_ALARM: break;
case RTC_DAY_OF_WEEK: val = ds1302_readbyte(RTC_ADDR_DAY); break;
case RTC_DAY_OF_MONTH: val = ds1302_readbyte(RTC_ADDR_DATE); break;
case RTC_MONTH: val = ds1302_readbyte(RTC_ADDR_MON); break;
case RTC_YEAR: val = ds1302_readbyte(RTC_ADDR_YEAR); break;
case RTC_REG_A: /* RTC_FREQ_SELECT */ break;
case RTC_REG_B: /* RTC_CONTROL */ break;
case RTC_REG_C: /* RTC_INTR_FLAGS */ break;
case RTC_REG_D: val = RTC_VRT /* RTC_VALID */; break;
default: break;
}
return(val);
}
void secureedge5410_cmos_write(unsigned char val, int addr)
{
if (!use_ds1302) {
__CMOS_WRITE(val, addr, w);
return;
}
switch(addr) {
case RTC_SECONDS: ds1302_writebyte(RTC_ADDR_SEC, val); break;
case RTC_SECONDS_ALARM: break;
case RTC_MINUTES: ds1302_writebyte(RTC_ADDR_MIN, val); break;
case RTC_MINUTES_ALARM: break;
case RTC_HOURS: ds1302_writebyte(RTC_ADDR_HOUR, val); break;
case RTC_HOURS_ALARM: break;
case RTC_DAY_OF_WEEK: ds1302_writebyte(RTC_ADDR_DAY, val); break;
case RTC_DAY_OF_MONTH: ds1302_writebyte(RTC_ADDR_DATE, val); break;
case RTC_MONTH: ds1302_writebyte(RTC_ADDR_MON, val); break;
case RTC_YEAR: ds1302_writebyte(RTC_ADDR_YEAR, val); break;
case RTC_REG_A: /* RTC_FREQ_SELECT */ break;
case RTC_REG_B: /* RTC_CONTROL */ break;
case RTC_REG_C: /* RTC_INTR_FLAGS */ break;
case RTC_REG_D: /* RTC_VALID */ break;
default: break;
}
}
|
