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
|
// SPDX-License-Identifier: GPL-2.0
/*
* 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.
* Copyright (C) 2003-2005 Benjamin Herrenschmidt.
*
*/
#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/time.h>
#include <linux/adb.h>
#include <linux/cuda.h>
#include <linux/pmu.h>
#include <linux/interrupt.h>
#include <linux/hardirq.h>
#include <linux/rtc.h>
#include <linux/of_address.h>
#include <asm/sections.h>
#include <asm/io.h>
#include <asm/machdep.h>
#include <asm/time.h>
#include <asm/nvram.h>
#include <asm/smu.h>
#include "pmac.h"
#undef DEBUG
#ifdef DEBUG
#define DBG(x...) printk(x)
#else
#define DBG(x...)
#endif
/*
* 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 */
long __init pmac_time_init(void)
{
s32 delta = 0;
#if defined(CONFIG_NVRAM) && defined(CONFIG_PPC32)
int dst;
delta = ((s32)pmac_xpram_read(PMAC_XPRAM_MACHINE_LOC + 0x9)) << 16;
delta |= ((s32)pmac_xpram_read(PMAC_XPRAM_MACHINE_LOC + 0xa)) << 8;
delta |= pmac_xpram_read(PMAC_XPRAM_MACHINE_LOC + 0xb);
if (delta & 0x00800000UL)
delta |= 0xFF000000UL;
dst = ((pmac_xpram_read(PMAC_XPRAM_MACHINE_LOC + 0x8) & 0x80) != 0);
printk("GMT Delta read from XPRAM: %d minutes, DST: %s\n", delta/60,
dst ? "on" : "off");
#endif
return delta;
}
#ifdef CONFIG_PMAC_SMU
static time64_t smu_get_time(void)
{
struct rtc_time tm;
if (smu_get_rtc_time(&tm, 1))
return 0;
return rtc_tm_to_time64(&tm);
}
#endif
/* Can't be __init, it's called when suspending and resuming */
time64_t pmac_get_boot_time(void)
{
/* Get the time from the RTC, used only at boot time */
switch (sys_ctrler) {
#ifdef CONFIG_ADB_CUDA
case SYS_CTRLER_CUDA:
return cuda_get_time();
#endif
#ifdef CONFIG_ADB_PMU
case SYS_CTRLER_PMU:
return pmu_get_time();
#endif
#ifdef CONFIG_PMAC_SMU
case SYS_CTRLER_SMU:
return smu_get_time();
#endif
default:
return 0;
}
}
void pmac_get_rtc_time(struct rtc_time *tm)
{
/* Get the time from the RTC, used only at boot time */
switch (sys_ctrler) {
#ifdef CONFIG_ADB_CUDA
case SYS_CTRLER_CUDA:
rtc_time64_to_tm(cuda_get_time(), tm);
break;
#endif
#ifdef CONFIG_ADB_PMU
case SYS_CTRLER_PMU:
rtc_time64_to_tm(pmu_get_time(), tm);
break;
#endif
#ifdef CONFIG_PMAC_SMU
case SYS_CTRLER_SMU:
smu_get_rtc_time(tm, 1);
break;
#endif
default:
;
}
}
int pmac_set_rtc_time(struct rtc_time *tm)
{
switch (sys_ctrler) {
#ifdef CONFIG_ADB_CUDA
case SYS_CTRLER_CUDA:
return cuda_set_rtc_time(tm);
#endif
#ifdef CONFIG_ADB_PMU
case SYS_CTRLER_PMU:
return pmu_set_rtc_time(tm);
#endif
#ifdef CONFIG_PMAC_SMU
case SYS_CTRLER_SMU:
return smu_set_rtc_time(tm, 1);
#endif
default:
return -ENODEV;
}
}
#ifdef CONFIG_PPC32
/*
* Calibrate the decrementer register using VIA timer 1.
* This is used both on powermacs and CHRP machines.
*/
static int __init via_calibrate_decr(void)
{
struct device_node *vias;
volatile unsigned char __iomem *via;
int count = VIA_TIMER_FREQ_6 / 100;
unsigned int dstart, dend;
struct resource rsrc;
vias = of_find_node_by_name(NULL, "via-cuda");
if (vias == NULL)
vias = of_find_node_by_name(NULL, "via-pmu");
if (vias == NULL)
vias = of_find_node_by_name(NULL, "via");
if (vias == NULL || of_address_to_resource(vias, 0, &rsrc)) {
of_node_put(vias);
return 0;
}
of_node_put(vias);
via = ioremap(rsrc.start, resource_size(&rsrc));
if (via == NULL) {
printk(KERN_ERR "Failed to map VIA for timer calibration !\n");
return 0;
}
/* 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();
ppc_tb_freq = (dstart - dend) * 100 / 6;
iounmap(via);
return 1;
}
#endif
/*
* Query the OF and get the decr frequency.
*/
void __init pmac_calibrate_decr(void)
{
generic_calibrate_decr();
#ifdef CONFIG_PPC32
/* We assume MacRISC2 machines have correct device-tree
* calibration. That's better since the VIA itself seems
* to be slightly off. --BenH
*/
if (!of_machine_is_compatible("MacRISC2") &&
!of_machine_is_compatible("MacRISC3") &&
!of_machine_is_compatible("MacRISC4"))
if (via_calibrate_decr())
return;
/* Special case: QuickSilver G4s seem to have a badly calibrated
* timebase-frequency in OF, VIA is much better on these. We should
* probably implement calibration based on the KL timer on these
* machines anyway... -BenH
*/
if (of_machine_is_compatible("PowerMac3,5"))
if (via_calibrate_decr())
return;
#endif
}
|
