1 /*
2 * PowerNV Real Time Clock.
3 *
4 * Copyright 2011 IBM Corp.
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 */
11
12
13 #include <linux/kernel.h>
14 #include <linux/time.h>
15 #include <linux/bcd.h>
16 #include <linux/rtc.h>
17 #include <linux/delay.h>
18
19 #include <asm/opal.h>
20 #include <asm/firmware.h>
21 #include <asm/machdep.h>
22
opal_to_tm(u32 y_m_d,u64 h_m_s_ms,struct rtc_time * tm)23 static void opal_to_tm(u32 y_m_d, u64 h_m_s_ms, struct rtc_time *tm)
24 {
25 tm->tm_year = ((bcd2bin(y_m_d >> 24) * 100) +
26 bcd2bin((y_m_d >> 16) & 0xff)) - 1900;
27 tm->tm_mon = bcd2bin((y_m_d >> 8) & 0xff) - 1;
28 tm->tm_mday = bcd2bin(y_m_d & 0xff);
29 tm->tm_hour = bcd2bin((h_m_s_ms >> 56) & 0xff);
30 tm->tm_min = bcd2bin((h_m_s_ms >> 48) & 0xff);
31 tm->tm_sec = bcd2bin((h_m_s_ms >> 40) & 0xff);
32
33 GregorianDay(tm);
34 }
35
opal_get_boot_time(void)36 unsigned long __init opal_get_boot_time(void)
37 {
38 struct rtc_time tm;
39 u32 y_m_d;
40 u64 h_m_s_ms;
41 __be32 __y_m_d;
42 __be64 __h_m_s_ms;
43 long rc = OPAL_BUSY;
44
45 if (!opal_check_token(OPAL_RTC_READ))
46 goto out;
47
48 while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
49 rc = opal_rtc_read(&__y_m_d, &__h_m_s_ms);
50 if (rc == OPAL_BUSY_EVENT)
51 opal_poll_events(NULL);
52 else
53 mdelay(10);
54 }
55 if (rc != OPAL_SUCCESS)
56 goto out;
57
58 y_m_d = be32_to_cpu(__y_m_d);
59 h_m_s_ms = be64_to_cpu(__h_m_s_ms);
60 opal_to_tm(y_m_d, h_m_s_ms, &tm);
61 return mktime(tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday,
62 tm.tm_hour, tm.tm_min, tm.tm_sec);
63 out:
64 ppc_md.get_rtc_time = NULL;
65 ppc_md.set_rtc_time = NULL;
66 return 0;
67 }
68
opal_get_rtc_time(struct rtc_time * tm)69 void opal_get_rtc_time(struct rtc_time *tm)
70 {
71 long rc = OPAL_BUSY;
72 u32 y_m_d;
73 u64 h_m_s_ms;
74 __be32 __y_m_d;
75 __be64 __h_m_s_ms;
76
77 while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
78 rc = opal_rtc_read(&__y_m_d, &__h_m_s_ms);
79 if (rc == OPAL_BUSY_EVENT)
80 opal_poll_events(NULL);
81 else
82 mdelay(10);
83 }
84 if (rc != OPAL_SUCCESS)
85 return;
86 y_m_d = be32_to_cpu(__y_m_d);
87 h_m_s_ms = be64_to_cpu(__h_m_s_ms);
88 opal_to_tm(y_m_d, h_m_s_ms, tm);
89 }
90
opal_set_rtc_time(struct rtc_time * tm)91 int opal_set_rtc_time(struct rtc_time *tm)
92 {
93 long rc = OPAL_BUSY;
94 u32 y_m_d = 0;
95 u64 h_m_s_ms = 0;
96
97 y_m_d |= ((u32)bin2bcd((tm->tm_year + 1900) / 100)) << 24;
98 y_m_d |= ((u32)bin2bcd((tm->tm_year + 1900) % 100)) << 16;
99 y_m_d |= ((u32)bin2bcd((tm->tm_mon + 1))) << 8;
100 y_m_d |= ((u32)bin2bcd(tm->tm_mday));
101
102 h_m_s_ms |= ((u64)bin2bcd(tm->tm_hour)) << 56;
103 h_m_s_ms |= ((u64)bin2bcd(tm->tm_min)) << 48;
104 h_m_s_ms |= ((u64)bin2bcd(tm->tm_sec)) << 40;
105
106 while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
107 rc = opal_rtc_write(y_m_d, h_m_s_ms);
108 if (rc == OPAL_BUSY_EVENT)
109 opal_poll_events(NULL);
110 else
111 mdelay(10);
112 }
113 return rc == OPAL_SUCCESS ? 0 : -EIO;
114 }
115