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
|
/*
* Support for periodic interrupts (100 per second) and for getting
* the current time from the RTC on Power Macintoshes.
*
* We use the decrementer register for our periodic interrupts.
*
* Paul Mackerras August 1996.
* Copyright (C) 1996 Paul Mackerras.
*/
#include <linux/config.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/param.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/init.h>
#include <linux/adb.h>
#include <linux/cuda.h>
#include <linux/pmu.h>
#include <asm/init.h>
#include <asm/prom.h>
#include <asm/system.h>
#include <asm/io.h>
#include <asm/pgtable.h>
#include <asm/machdep.h>
#include "time.h"
extern rwlock_t xtime_lock;
/* Apparently the RTC stores seconds since 1 Jan 1904 */
#define RTC_OFFSET 2082844800
/*
* Calibrate the decrementer frequency with the VIA timer 1.
*/
#define VIA_TIMER_FREQ_6 4700000 /* time 1 frequency * 6 */
/* VIA registers */
#define RS 0x200 /* skip between registers */
#define T1CL (4*RS) /* Timer 1 ctr/latch (low 8 bits) */
#define T1CH (5*RS) /* Timer 1 counter (high 8 bits) */
#define T1LL (6*RS) /* Timer 1 latch (low 8 bits) */
#define T1LH (7*RS) /* Timer 1 latch (high 8 bits) */
#define ACR (11*RS) /* Auxiliary control register */
#define IFR (13*RS) /* Interrupt flag register */
/* Bits in ACR */
#define T1MODE 0xc0 /* Timer 1 mode */
#define T1MODE_CONT 0x40 /* continuous interrupts */
/* Bits in IFR and IER */
#define T1_INT 0x40 /* Timer 1 interrupt */
__pmac
unsigned long pmac_get_rtc_time(void)
{
#ifdef CONFIG_ADB
struct adb_request req;
#endif
/* Get the time from the RTC */
switch (sys_ctrler) {
#ifdef CONFIG_ADB_CUDA
case SYS_CTRLER_CUDA:
if (cuda_request(&req, NULL, 2, CUDA_PACKET, CUDA_GET_TIME) < 0)
return 0;
while (!req.complete)
cuda_poll();
if (req.reply_len != 7)
printk(KERN_ERR "pmac_get_rtc_time: got %d byte reply\n",
req.reply_len);
return (req.reply[3] << 24) + (req.reply[4] << 16)
+ (req.reply[5] << 8) + req.reply[6] - RTC_OFFSET;
#endif /* CONFIG_ADB_CUDA */
#ifdef CONFIG_ADB_PMU
case SYS_CTRLER_PMU:
if (pmu_request(&req, NULL, 1, PMU_READ_RTC) < 0)
return 0;
while (!req.complete)
pmu_poll();
if (req.reply_len != 5)
printk(KERN_ERR "pmac_get_rtc_time: got %d byte reply\n",
req.reply_len);
return (req.reply[1] << 24) + (req.reply[2] << 16)
+ (req.reply[3] << 8) + req.reply[4] - RTC_OFFSET;
#endif /* CONFIG_ADB_PMU */
default:
return 0;
}
}
int pmac_set_rtc_time(unsigned long nowtime)
{
return 0;
}
/*
* Calibrate the decrementer register using VIA timer 1.
* This is used both on powermacs and CHRP machines.
*/
int __init via_calibrate_decr(void)
{
struct device_node *vias;
volatile unsigned char *via;
int count = VIA_TIMER_FREQ_6 / HZ;
unsigned int dstart, dend;
vias = find_devices("via-cuda");
if (vias == 0)
vias = find_devices("via-pmu");
if (vias == 0)
vias = find_devices("via");
if (vias == 0 || vias->n_addrs == 0)
return 0;
via = (volatile unsigned char *)
ioremap(vias->addrs[0].address, vias->addrs[0].size);
/* set timer 1 for continuous interrupts */
out_8(&via[ACR], (via[ACR] & ~T1MODE) | T1MODE_CONT);
/* set the counter to a small value */
out_8(&via[T1CH], 2);
/* set the latch to `count' */
out_8(&via[T1LL], count);
out_8(&via[T1LH], count >> 8);
/* wait until it hits 0 */
while ((in_8(&via[IFR]) & T1_INT) == 0)
;
dstart = get_dec();
/* clear the interrupt & wait until it hits 0 again */
in_8(&via[T1CL]);
while ((in_8(&via[IFR]) & T1_INT) == 0)
;
dend = get_dec();
decrementer_count = (dstart - dend) / 6;
count_period_num = 60;
count_period_den = decrementer_count * 6 * HZ / 100000;
printk(KERN_INFO "via_calibrate_decr: decrementer_count = %u (%u ticks)\n",
decrementer_count, dstart - dend);
return 1;
}
#ifdef CONFIG_PMAC_PBOOK
/*
* Reset the time after a sleep.
*/
static int time_sleep_notify(struct pmu_sleep_notifier *self, int when)
{
static unsigned long time_diff;
unsigned long flags;
switch (when) {
case PBOOK_SLEEP_NOW:
read_lock_irqsave(&xtime_lock, flags);
time_diff = xtime.tv_sec - pmac_get_rtc_time();
read_unlock_irqrestore(&xtime_lock, flags);
break;
case PBOOK_WAKE:
write_lock_irqsave(&xtime_lock, flags);
xtime.tv_sec = pmac_get_rtc_time() + time_diff;
xtime.tv_usec = 0;
set_dec(decrementer_count);
last_rtc_update = xtime.tv_sec;
write_unlock_irqrestore(&xtime_lock, flags);
break;
}
return PBOOK_SLEEP_OK;
}
static struct pmu_sleep_notifier time_sleep_notifier = {
time_sleep_notify, SLEEP_LEVEL_MISC,
};
#endif /* CONFIG_PMAC_PBOOK */
/*
* Query the OF and get the decr frequency.
* This was taken from the pmac time_init() when merging the prep/pmac
* time functions.
*/
void __init pmac_calibrate_decr(void)
{
struct device_node *cpu;
int freq, *fp, divisor;
#ifdef CONFIG_PMAC_PBOOK
pmu_register_sleep_notifier(&time_sleep_notifier);
#endif /* CONFIG_PMAC_PBOOK */
if (via_calibrate_decr())
return;
/*
* The cpu node should have a timebase-frequency property
* to tell us the rate at which the decrementer counts.
*/
cpu = find_type_devices("cpu");
if (cpu == 0)
panic("can't find cpu node in time_init");
fp = (int *) get_property(cpu, "timebase-frequency", NULL);
if (fp == 0)
panic("can't get cpu timebase frequency");
freq = *fp * 60; /* try to make freq/1e6 an integer */
divisor = 60;
printk("time_init: decrementer frequency = %d/%d\n",
freq, divisor);
decrementer_count = freq / HZ / divisor;
count_period_num = divisor;
count_period_den = freq / 1000000;
}
|
