2 * RTC configuration and clock read
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25 #include "qemu/osdep.h"
26 #include "qemu/cutils.h"
27 #include "qapi/error.h"
28 #include "qapi/qmp/qerror.h"
29 #include "qemu/error-report.h"
30 #include "qemu/option.h"
31 #include "qemu/timer.h"
32 #include "qom/object.h"
33 #include "sysemu/replay.h"
34 #include "sysemu/sysemu.h"
35 #include "sysemu/rtc.h"
36 #include "hw/rtc/mc146818rtc.h"
42 } rtc_base_type = RTC_BASE_UTC;
43 static time_t rtc_ref_start_datetime;
44 static int rtc_realtime_clock_offset; /* used only with QEMU_CLOCK_REALTIME */
45 static int rtc_host_datetime_offset = -1; /* valid & used only with
47 QEMUClockType rtc_clock;
48 /***********************************************************/
49 /* RTC reference time/date access */
50 static time_t qemu_ref_timedate(QEMUClockType clock)
52 time_t value = qemu_clock_get_ms(clock) / 1000;
54 case QEMU_CLOCK_REALTIME:
55 value -= rtc_realtime_clock_offset;
57 case QEMU_CLOCK_VIRTUAL:
58 value += rtc_ref_start_datetime;
61 if (rtc_base_type == RTC_BASE_DATETIME) {
62 value -= rtc_host_datetime_offset;
71 void qemu_get_timedate(struct tm *tm, time_t offset)
73 time_t ti = qemu_ref_timedate(rtc_clock);
77 switch (rtc_base_type) {
78 case RTC_BASE_DATETIME:
82 case RTC_BASE_LOCALTIME:
88 time_t qemu_timedate_diff(struct tm *tm)
92 switch (rtc_base_type) {
93 case RTC_BASE_DATETIME:
95 seconds = mktimegm(tm);
97 case RTC_BASE_LOCALTIME:
100 tmp.tm_isdst = -1; /* use timezone to figure it out */
101 seconds = mktime(&tmp);
108 return seconds - qemu_ref_timedate(QEMU_CLOCK_HOST);
111 static void configure_rtc_base_datetime(const char *startdate)
113 time_t rtc_start_datetime;
116 if (sscanf(startdate, "%d-%d-%dT%d:%d:%d", &tm.tm_year, &tm.tm_mon,
117 &tm.tm_mday, &tm.tm_hour, &tm.tm_min, &tm.tm_sec) == 6) {
119 } else if (sscanf(startdate, "%d-%d-%d",
120 &tm.tm_year, &tm.tm_mon, &tm.tm_mday) == 3) {
129 rtc_start_datetime = mktimegm(&tm);
130 if (rtc_start_datetime == -1) {
132 error_report("invalid datetime format");
133 error_printf("valid formats: "
134 "'2006-06-17T16:01:21' or '2006-06-17'\n");
137 rtc_host_datetime_offset = rtc_ref_start_datetime - rtc_start_datetime;
138 rtc_ref_start_datetime = rtc_start_datetime;
141 void configure_rtc(QemuOpts *opts)
146 rtc_clock = QEMU_CLOCK_HOST;
147 rtc_ref_start_datetime = qemu_clock_get_ms(QEMU_CLOCK_HOST) / 1000;
148 rtc_realtime_clock_offset = qemu_clock_get_ms(QEMU_CLOCK_REALTIME) / 1000;
150 value = qemu_opt_get(opts, "base");
152 if (!strcmp(value, "utc")) {
153 rtc_base_type = RTC_BASE_UTC;
154 } else if (!strcmp(value, "localtime")) {
155 rtc_base_type = RTC_BASE_LOCALTIME;
156 replay_add_blocker("-rtc base=localtime");
158 rtc_base_type = RTC_BASE_DATETIME;
159 configure_rtc_base_datetime(value);
162 value = qemu_opt_get(opts, "clock");
164 if (!strcmp(value, "host")) {
165 rtc_clock = QEMU_CLOCK_HOST;
166 } else if (!strcmp(value, "rt")) {
167 rtc_clock = QEMU_CLOCK_REALTIME;
168 } else if (!strcmp(value, "vm")) {
169 rtc_clock = QEMU_CLOCK_VIRTUAL;
171 error_report("invalid option value '%s'", value);
175 value = qemu_opt_get(opts, "driftfix");
177 if (!strcmp(value, "slew")) {
178 object_register_sugar_prop(TYPE_MC146818_RTC,
182 if (!object_class_by_name(TYPE_MC146818_RTC)) {
183 warn_report("driftfix 'slew' is not available with this machine");
185 } else if (!strcmp(value, "none")) {
186 /* discard is default */
188 error_report("invalid option value '%s'", value);