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-rw-r--r--arch/ppc/platforms/chrp_time.c251
1 files changed, 0 insertions, 251 deletions
diff --git a/arch/ppc/platforms/chrp_time.c b/arch/ppc/platforms/chrp_time.c
deleted file mode 100644
index c8627770af13..000000000000
--- a/arch/ppc/platforms/chrp_time.c
+++ /dev/null
@@ -1,251 +0,0 @@
1/*
2 * Copyright (C) 1991, 1992, 1995 Linus Torvalds
3 *
4 * Adapted for PowerPC (PReP) by Gary Thomas
5 * Modified by Cort Dougan (cort@cs.nmt.edu).
6 * Copied and modified from arch/i386/kernel/time.c
7 *
8 */
9#include <linux/errno.h>
10#include <linux/sched.h>
11#include <linux/kernel.h>
12#include <linux/param.h>
13#include <linux/string.h>
14#include <linux/mm.h>
15#include <linux/interrupt.h>
16#include <linux/time.h>
17#include <linux/timex.h>
18#include <linux/kernel_stat.h>
19#include <linux/mc146818rtc.h>
20#include <linux/init.h>
21#include <linux/bcd.h>
22
23#include <asm/io.h>
24#include <asm/nvram.h>
25#include <asm/prom.h>
26#include <asm/sections.h>
27#include <asm/time.h>
28
29extern spinlock_t rtc_lock;
30
31static int nvram_as1 = NVRAM_AS1;
32static int nvram_as0 = NVRAM_AS0;
33static int nvram_data = NVRAM_DATA;
34
35long __init chrp_time_init(void)
36{
37 struct device_node *rtcs;
38 int base;
39
40 rtcs = find_compatible_devices("rtc", "pnpPNP,b00");
41 if (rtcs == NULL)
42 rtcs = find_compatible_devices("rtc", "ds1385-rtc");
43 if (rtcs == NULL || rtcs->addrs == NULL)
44 return 0;
45 base = rtcs->addrs[0].address;
46 nvram_as1 = 0;
47 nvram_as0 = base;
48 nvram_data = base + 1;
49
50 return 0;
51}
52
53int chrp_cmos_clock_read(int addr)
54{
55 if (nvram_as1 != 0)
56 outb(addr>>8, nvram_as1);
57 outb(addr, nvram_as0);
58 return (inb(nvram_data));
59}
60
61void chrp_cmos_clock_write(unsigned long val, int addr)
62{
63 if (nvram_as1 != 0)
64 outb(addr>>8, nvram_as1);
65 outb(addr, nvram_as0);
66 outb(val, nvram_data);
67 return;
68}
69
70/*
71 * Set the hardware clock. -- Cort
72 */
73int chrp_set_rtc_time(unsigned long nowtime)
74{
75 unsigned char save_control, save_freq_select;
76 struct rtc_time tm;
77
78 spin_lock(&rtc_lock);
79 to_tm(nowtime, &tm);
80
81 save_control = chrp_cmos_clock_read(RTC_CONTROL); /* tell the clock it's being set */
82
83 chrp_cmos_clock_write((save_control|RTC_SET), RTC_CONTROL);
84
85 save_freq_select = chrp_cmos_clock_read(RTC_FREQ_SELECT); /* stop and reset prescaler */
86
87 chrp_cmos_clock_write((save_freq_select|RTC_DIV_RESET2), RTC_FREQ_SELECT);
88
89 tm.tm_year -= 1900;
90 if (!(save_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD) {
91 BIN_TO_BCD(tm.tm_sec);
92 BIN_TO_BCD(tm.tm_min);
93 BIN_TO_BCD(tm.tm_hour);
94 BIN_TO_BCD(tm.tm_mon);
95 BIN_TO_BCD(tm.tm_mday);
96 BIN_TO_BCD(tm.tm_year);
97 }
98 chrp_cmos_clock_write(tm.tm_sec,RTC_SECONDS);
99 chrp_cmos_clock_write(tm.tm_min,RTC_MINUTES);
100 chrp_cmos_clock_write(tm.tm_hour,RTC_HOURS);
101 chrp_cmos_clock_write(tm.tm_mon,RTC_MONTH);
102 chrp_cmos_clock_write(tm.tm_mday,RTC_DAY_OF_MONTH);
103 chrp_cmos_clock_write(tm.tm_year,RTC_YEAR);
104
105 /* The following flags have to be released exactly in this order,
106 * otherwise the DS12887 (popular MC146818A clone with integrated
107 * battery and quartz) will not reset the oscillator and will not
108 * update precisely 500 ms later. You won't find this mentioned in
109 * the Dallas Semiconductor data sheets, but who believes data
110 * sheets anyway ... -- Markus Kuhn
111 */
112 chrp_cmos_clock_write(save_control, RTC_CONTROL);
113 chrp_cmos_clock_write(save_freq_select, RTC_FREQ_SELECT);
114
115 spin_unlock(&rtc_lock);
116 return 0;
117}
118
119unsigned long chrp_get_rtc_time(void)
120{
121 unsigned int year, mon, day, hour, min, sec;
122 int uip, i;
123
124 /* The Linux interpretation of the CMOS clock register contents:
125 * When the Update-In-Progress (UIP) flag goes from 1 to 0, the
126 * RTC registers show the second which has precisely just started.
127 * Let's hope other operating systems interpret the RTC the same way.
128 */
129
130 /* Since the UIP flag is set for about 2.2 ms and the clock
131 * is typically written with a precision of 1 jiffy, trying
132 * to obtain a precision better than a few milliseconds is
133 * an illusion. Only consistency is interesting, this also
134 * allows to use the routine for /dev/rtc without a potential
135 * 1 second kernel busy loop triggered by any reader of /dev/rtc.
136 */
137
138 for ( i = 0; i<1000000; i++) {
139 uip = chrp_cmos_clock_read(RTC_FREQ_SELECT);
140 sec = chrp_cmos_clock_read(RTC_SECONDS);
141 min = chrp_cmos_clock_read(RTC_MINUTES);
142 hour = chrp_cmos_clock_read(RTC_HOURS);
143 day = chrp_cmos_clock_read(RTC_DAY_OF_MONTH);
144 mon = chrp_cmos_clock_read(RTC_MONTH);
145 year = chrp_cmos_clock_read(RTC_YEAR);
146 uip |= chrp_cmos_clock_read(RTC_FREQ_SELECT);
147 if ((uip & RTC_UIP)==0) break;
148 }
149
150 if (!(chrp_cmos_clock_read(RTC_CONTROL) & RTC_DM_BINARY) || RTC_ALWAYS_BCD)
151 {
152 BCD_TO_BIN(sec);
153 BCD_TO_BIN(min);
154 BCD_TO_BIN(hour);
155 BCD_TO_BIN(day);
156 BCD_TO_BIN(mon);
157 BCD_TO_BIN(year);
158 }
159 if ((year += 1900) < 1970)
160 year += 100;
161 return mktime(year, mon, day, hour, min, sec);
162}
163
164/*
165 * Calibrate the decrementer frequency with the VIA timer 1.
166 */
167#define VIA_TIMER_FREQ_6 4700000 /* time 1 frequency * 6 */
168
169/* VIA registers */
170#define RS 0x200 /* skip between registers */
171#define T1CL (4*RS) /* Timer 1 ctr/latch (low 8 bits) */
172#define T1CH (5*RS) /* Timer 1 counter (high 8 bits) */
173#define T1LL (6*RS) /* Timer 1 latch (low 8 bits) */
174#define T1LH (7*RS) /* Timer 1 latch (high 8 bits) */
175#define ACR (11*RS) /* Auxiliary control register */
176#define IFR (13*RS) /* Interrupt flag register */
177
178/* Bits in ACR */
179#define T1MODE 0xc0 /* Timer 1 mode */
180#define T1MODE_CONT 0x40 /* continuous interrupts */
181
182/* Bits in IFR and IER */
183#define T1_INT 0x40 /* Timer 1 interrupt */
184
185static int __init chrp_via_calibrate_decr(void)
186{
187 struct device_node *vias;
188 volatile unsigned char __iomem *via;
189 int count = VIA_TIMER_FREQ_6 / 100;
190 unsigned int dstart, dend;
191
192 vias = find_devices("via-cuda");
193 if (vias == 0)
194 vias = find_devices("via");
195 if (vias == 0 || vias->n_addrs == 0)
196 return 0;
197 via = ioremap(vias->addrs[0].address, vias->addrs[0].size);
198
199 /* set timer 1 for continuous interrupts */
200 out_8(&via[ACR], (via[ACR] & ~T1MODE) | T1MODE_CONT);
201 /* set the counter to a small value */
202 out_8(&via[T1CH], 2);
203 /* set the latch to `count' */
204 out_8(&via[T1LL], count);
205 out_8(&via[T1LH], count >> 8);
206 /* wait until it hits 0 */
207 while ((in_8(&via[IFR]) & T1_INT) == 0)
208 ;
209 dstart = get_dec();
210 /* clear the interrupt & wait until it hits 0 again */
211 in_8(&via[T1CL]);
212 while ((in_8(&via[IFR]) & T1_INT) == 0)
213 ;
214 dend = get_dec();
215
216 tb_ticks_per_jiffy = (dstart - dend) / ((6 * HZ)/100);
217 tb_to_us = mulhwu_scale_factor(dstart - dend, 60000);
218
219 printk(KERN_INFO "via_calibrate_decr: ticks per jiffy = %u (%u ticks)\n",
220 tb_ticks_per_jiffy, dstart - dend);
221
222 iounmap(via);
223
224 return 1;
225}
226
227void __init chrp_calibrate_decr(void)
228{
229 struct device_node *cpu;
230 unsigned int freq, *fp;
231
232 if (chrp_via_calibrate_decr())
233 return;
234
235 /*
236 * The cpu node should have a timebase-frequency property
237 * to tell us the rate at which the decrementer counts.
238 */
239 freq = 16666000; /* hardcoded default */
240 cpu = find_type_devices("cpu");
241 if (cpu != 0) {
242 fp = (unsigned int *)
243 get_property(cpu, "timebase-frequency", NULL);
244 if (fp != 0)
245 freq = *fp;
246 }
247 printk("time_init: decrementer frequency = %u.%.6u MHz\n",
248 freq/1000000, freq%1000000);
249 tb_ticks_per_jiffy = freq / HZ;
250 tb_to_us = mulhwu_scale_factor(freq, 1000000);
251}
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