xref: /openbmc/qemu/hw/ppc/spapr_rtc.c (revision 1f7685fa)
1 /*
2  * QEMU PowerPC pSeries Logical Partition (aka sPAPR) hardware System Emulator
3  *
4  * RTAS Real Time Clock
5  *
6  * Copyright (c) 2010-2011 David Gibson, IBM Corporation.
7  * Copyright 2014 David Gibson, Red Hat.
8  *
9  * Permission is hereby granted, free of charge, to any person obtaining a copy
10  * of this software and associated documentation files (the "Software"), to deal
11  * in the Software without restriction, including without limitation the rights
12  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
13  * copies of the Software, and to permit persons to whom the Software is
14  * furnished to do so, subject to the following conditions:
15  *
16  * The above copyright notice and this permission notice shall be included in
17  * all copies or substantial portions of the Software.
18  *
19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
20  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
22  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
23  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
24  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
25  * THE SOFTWARE.
26  *
27  */
28 #include "qemu/osdep.h"
29 #include "cpu.h"
30 #include "qemu/timer.h"
31 #include "sysemu/sysemu.h"
32 #include "hw/ppc/spapr.h"
33 #include "qapi-event.h"
34 #include "qemu/cutils.h"
35 
36 #define SPAPR_RTC(obj) \
37     OBJECT_CHECK(sPAPRRTCState, (obj), TYPE_SPAPR_RTC)
38 
39 typedef struct sPAPRRTCState sPAPRRTCState;
40 struct sPAPRRTCState {
41     /*< private >*/
42     SysBusDevice parent_obj;
43     int64_t ns_offset;
44 };
45 
46 void spapr_rtc_read(DeviceState *dev, struct tm *tm, uint32_t *ns)
47 {
48     sPAPRRTCState *rtc = SPAPR_RTC(dev);
49     int64_t host_ns = qemu_clock_get_ns(rtc_clock);
50     int64_t guest_ns;
51     time_t guest_s;
52 
53     assert(rtc);
54 
55     guest_ns = host_ns + rtc->ns_offset;
56     guest_s = guest_ns / NANOSECONDS_PER_SECOND;
57 
58     if (tm) {
59         gmtime_r(&guest_s, tm);
60     }
61     if (ns) {
62         *ns = guest_ns;
63     }
64 }
65 
66 int spapr_rtc_import_offset(DeviceState *dev, int64_t legacy_offset)
67 {
68     sPAPRRTCState *rtc;
69 
70     if (!dev) {
71         return -ENODEV;
72     }
73 
74     rtc = SPAPR_RTC(dev);
75 
76     rtc->ns_offset = legacy_offset * NANOSECONDS_PER_SECOND;
77 
78     return 0;
79 }
80 
81 static void rtas_get_time_of_day(PowerPCCPU *cpu, sPAPRMachineState *spapr,
82                                  uint32_t token, uint32_t nargs,
83                                  target_ulong args,
84                                  uint32_t nret, target_ulong rets)
85 {
86     struct tm tm;
87     uint32_t ns;
88 
89     if ((nargs != 0) || (nret != 8)) {
90         rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
91         return;
92     }
93 
94     if (!spapr->rtc) {
95         rtas_st(rets, 0, RTAS_OUT_HW_ERROR);
96         return;
97     }
98 
99     spapr_rtc_read(spapr->rtc, &tm, &ns);
100 
101     rtas_st(rets, 0, RTAS_OUT_SUCCESS);
102     rtas_st(rets, 1, tm.tm_year + 1900);
103     rtas_st(rets, 2, tm.tm_mon + 1);
104     rtas_st(rets, 3, tm.tm_mday);
105     rtas_st(rets, 4, tm.tm_hour);
106     rtas_st(rets, 5, tm.tm_min);
107     rtas_st(rets, 6, tm.tm_sec);
108     rtas_st(rets, 7, ns);
109 }
110 
111 static void rtas_set_time_of_day(PowerPCCPU *cpu, sPAPRMachineState *spapr,
112                                  uint32_t token, uint32_t nargs,
113                                  target_ulong args,
114                                  uint32_t nret, target_ulong rets)
115 {
116     sPAPRRTCState *rtc;
117     struct tm tm;
118     time_t new_s;
119     int64_t host_ns;
120 
121     if ((nargs != 7) || (nret != 1)) {
122         rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
123         return;
124     }
125 
126     if (!spapr->rtc) {
127         rtas_st(rets, 0, RTAS_OUT_HW_ERROR);
128         return;
129     }
130 
131     tm.tm_year = rtas_ld(args, 0) - 1900;
132     tm.tm_mon = rtas_ld(args, 1) - 1;
133     tm.tm_mday = rtas_ld(args, 2);
134     tm.tm_hour = rtas_ld(args, 3);
135     tm.tm_min = rtas_ld(args, 4);
136     tm.tm_sec = rtas_ld(args, 5);
137 
138     new_s = mktimegm(&tm);
139     if (new_s == -1) {
140         rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
141         return;
142     }
143 
144     /* Generate a monitor event for the change */
145     qapi_event_send_rtc_change(qemu_timedate_diff(&tm), &error_abort);
146 
147     rtc = SPAPR_RTC(spapr->rtc);
148 
149     host_ns = qemu_clock_get_ns(rtc_clock);
150 
151     rtc->ns_offset = (new_s * NANOSECONDS_PER_SECOND) - host_ns;
152 
153     rtas_st(rets, 0, RTAS_OUT_SUCCESS);
154 }
155 
156 static void spapr_rtc_qom_date(Object *obj, struct tm *current_tm, Error **errp)
157 {
158     spapr_rtc_read(DEVICE(obj), current_tm, NULL);
159 }
160 
161 static void spapr_rtc_realize(DeviceState *dev, Error **errp)
162 {
163     sPAPRRTCState *rtc = SPAPR_RTC(dev);
164     struct tm tm;
165     time_t host_s;
166     int64_t rtc_ns;
167 
168     /* Initialize the RTAS RTC from host time */
169 
170     qemu_get_timedate(&tm, 0);
171     host_s = mktimegm(&tm);
172     rtc_ns = qemu_clock_get_ns(rtc_clock);
173     rtc->ns_offset = host_s * NANOSECONDS_PER_SECOND - rtc_ns;
174 
175     object_property_add_tm(OBJECT(rtc), "date", spapr_rtc_qom_date, NULL);
176 }
177 
178 static const VMStateDescription vmstate_spapr_rtc = {
179     .name = "spapr/rtc",
180     .version_id = 1,
181     .minimum_version_id = 1,
182     .fields = (VMStateField[]) {
183         VMSTATE_INT64(ns_offset, sPAPRRTCState),
184         VMSTATE_END_OF_LIST()
185     },
186 };
187 
188 static void spapr_rtc_class_init(ObjectClass *oc, void *data)
189 {
190     DeviceClass *dc = DEVICE_CLASS(oc);
191 
192     dc->realize = spapr_rtc_realize;
193     dc->vmsd = &vmstate_spapr_rtc;
194 
195     spapr_rtas_register(RTAS_GET_TIME_OF_DAY, "get-time-of-day",
196                         rtas_get_time_of_day);
197     spapr_rtas_register(RTAS_SET_TIME_OF_DAY, "set-time-of-day",
198                         rtas_set_time_of_day);
199 }
200 
201 static const TypeInfo spapr_rtc_info = {
202     .name          = TYPE_SPAPR_RTC,
203     .parent        = TYPE_SYS_BUS_DEVICE,
204     .instance_size = sizeof(sPAPRRTCState),
205     .class_init    = spapr_rtc_class_init,
206 };
207 
208 static void spapr_rtc_register_types(void)
209 {
210     type_register_static(&spapr_rtc_info);
211 }
212 type_init(spapr_rtc_register_types)
213