xref: /openbmc/qemu/hw/ppc/spapr_rtc.c (revision 9884abee)
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 
35 #define SPAPR_RTC(obj) \
36     OBJECT_CHECK(sPAPRRTCState, (obj), TYPE_SPAPR_RTC)
37 
38 typedef struct sPAPRRTCState sPAPRRTCState;
39 struct sPAPRRTCState {
40     /*< private >*/
41     SysBusDevice parent_obj;
42     int64_t ns_offset;
43 };
44 
45 void spapr_rtc_read(DeviceState *dev, struct tm *tm, uint32_t *ns)
46 {
47     sPAPRRTCState *rtc = SPAPR_RTC(dev);
48     int64_t host_ns = qemu_clock_get_ns(rtc_clock);
49     int64_t guest_ns;
50     time_t guest_s;
51 
52     assert(rtc);
53 
54     guest_ns = host_ns + rtc->ns_offset;
55     guest_s = guest_ns / NANOSECONDS_PER_SECOND;
56 
57     if (tm) {
58         gmtime_r(&guest_s, tm);
59     }
60     if (ns) {
61         *ns = guest_ns;
62     }
63 }
64 
65 int spapr_rtc_import_offset(DeviceState *dev, int64_t legacy_offset)
66 {
67     sPAPRRTCState *rtc;
68 
69     if (!dev) {
70         return -ENODEV;
71     }
72 
73     rtc = SPAPR_RTC(dev);
74 
75     rtc->ns_offset = legacy_offset * NANOSECONDS_PER_SECOND;
76 
77     return 0;
78 }
79 
80 static void rtas_get_time_of_day(PowerPCCPU *cpu, sPAPRMachineState *spapr,
81                                  uint32_t token, uint32_t nargs,
82                                  target_ulong args,
83                                  uint32_t nret, target_ulong rets)
84 {
85     struct tm tm;
86     uint32_t ns;
87 
88     if ((nargs != 0) || (nret != 8)) {
89         rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
90         return;
91     }
92 
93     if (!spapr->rtc) {
94         rtas_st(rets, 0, RTAS_OUT_HW_ERROR);
95         return;
96     }
97 
98     spapr_rtc_read(spapr->rtc, &tm, &ns);
99 
100     rtas_st(rets, 0, RTAS_OUT_SUCCESS);
101     rtas_st(rets, 1, tm.tm_year + 1900);
102     rtas_st(rets, 2, tm.tm_mon + 1);
103     rtas_st(rets, 3, tm.tm_mday);
104     rtas_st(rets, 4, tm.tm_hour);
105     rtas_st(rets, 5, tm.tm_min);
106     rtas_st(rets, 6, tm.tm_sec);
107     rtas_st(rets, 7, ns);
108 }
109 
110 static void rtas_set_time_of_day(PowerPCCPU *cpu, sPAPRMachineState *spapr,
111                                  uint32_t token, uint32_t nargs,
112                                  target_ulong args,
113                                  uint32_t nret, target_ulong rets)
114 {
115     sPAPRRTCState *rtc;
116     struct tm tm;
117     time_t new_s;
118     int64_t host_ns;
119 
120     if ((nargs != 7) || (nret != 1)) {
121         rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
122         return;
123     }
124 
125     if (!spapr->rtc) {
126         rtas_st(rets, 0, RTAS_OUT_HW_ERROR);
127         return;
128     }
129 
130     tm.tm_year = rtas_ld(args, 0) - 1900;
131     tm.tm_mon = rtas_ld(args, 1) - 1;
132     tm.tm_mday = rtas_ld(args, 2);
133     tm.tm_hour = rtas_ld(args, 3);
134     tm.tm_min = rtas_ld(args, 4);
135     tm.tm_sec = rtas_ld(args, 5);
136 
137     new_s = mktimegm(&tm);
138     if (new_s == -1) {
139         rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
140         return;
141     }
142 
143     /* Generate a monitor event for the change */
144     qapi_event_send_rtc_change(qemu_timedate_diff(&tm), &error_abort);
145 
146     rtc = SPAPR_RTC(spapr->rtc);
147 
148     host_ns = qemu_clock_get_ns(rtc_clock);
149 
150     rtc->ns_offset = (new_s * NANOSECONDS_PER_SECOND) - host_ns;
151 
152     rtas_st(rets, 0, RTAS_OUT_SUCCESS);
153 }
154 
155 static void spapr_rtc_qom_date(Object *obj, struct tm *current_tm, Error **errp)
156 {
157     spapr_rtc_read(DEVICE(obj), current_tm, NULL);
158 }
159 
160 static void spapr_rtc_realize(DeviceState *dev, Error **errp)
161 {
162     sPAPRRTCState *rtc = SPAPR_RTC(dev);
163     struct tm tm;
164     time_t host_s;
165     int64_t rtc_ns;
166 
167     /* Initialize the RTAS RTC from host time */
168 
169     qemu_get_timedate(&tm, 0);
170     host_s = mktimegm(&tm);
171     rtc_ns = qemu_clock_get_ns(rtc_clock);
172     rtc->ns_offset = host_s * NANOSECONDS_PER_SECOND - rtc_ns;
173 
174     object_property_add_tm(OBJECT(rtc), "date", spapr_rtc_qom_date, NULL);
175 }
176 
177 static const VMStateDescription vmstate_spapr_rtc = {
178     .name = "spapr/rtc",
179     .version_id = 1,
180     .minimum_version_id = 1,
181     .fields = (VMStateField[]) {
182         VMSTATE_INT64(ns_offset, sPAPRRTCState),
183         VMSTATE_END_OF_LIST()
184     },
185 };
186 
187 static void spapr_rtc_class_init(ObjectClass *oc, void *data)
188 {
189     DeviceClass *dc = DEVICE_CLASS(oc);
190 
191     dc->realize = spapr_rtc_realize;
192     dc->vmsd = &vmstate_spapr_rtc;
193 
194     spapr_rtas_register(RTAS_GET_TIME_OF_DAY, "get-time-of-day",
195                         rtas_get_time_of_day);
196     spapr_rtas_register(RTAS_SET_TIME_OF_DAY, "set-time-of-day",
197                         rtas_set_time_of_day);
198 }
199 
200 static const TypeInfo spapr_rtc_info = {
201     .name          = TYPE_SPAPR_RTC,
202     .parent        = TYPE_SYS_BUS_DEVICE,
203     .instance_size = sizeof(sPAPRRTCState),
204     .class_init    = spapr_rtc_class_init,
205 };
206 
207 static void spapr_rtc_register_types(void)
208 {
209     type_register_static(&spapr_rtc_info);
210 }
211 type_init(spapr_rtc_register_types)
212