xref: /openbmc/qemu/hw/core/clock-vmstate.c (revision efb91426)
1 /*
2  * Clock migration structure
3  *
4  * Copyright GreenSocs 2019-2020
5  *
6  * Authors:
7  *  Damien Hedde
8  *
9  * This work is licensed under the terms of the GNU GPL, version 2 or later.
10  * See the COPYING file in the top-level directory.
11  */
12 
13 #include "qemu/osdep.h"
14 #include "migration/vmstate.h"
15 #include "hw/clock.h"
16 
17 static bool muldiv_needed(void *opaque)
18 {
19     Clock *clk = opaque;
20 
21     return clk->multiplier != 1 || clk->divider != 1;
22 }
23 
24 static int clock_pre_load(void *opaque)
25 {
26     Clock *clk = opaque;
27     /*
28      * The initial out-of-reset settings of the Clock might have been
29      * configured by the device to be different from what we set
30      * in clock_initfn(), so we must here set the default values to
31      * be used if they are not in the inbound migration state.
32      */
33     clk->multiplier = 1;
34     clk->divider = 1;
35 
36     return 0;
37 }
38 
39 const VMStateDescription vmstate_muldiv = {
40     .name = "clock/muldiv",
41     .version_id = 1,
42     .minimum_version_id = 1,
43     .needed = muldiv_needed,
44     .fields = (const VMStateField[]) {
45         VMSTATE_UINT32(multiplier, Clock),
46         VMSTATE_UINT32(divider, Clock),
47         VMSTATE_END_OF_LIST()
48     },
49 };
50 
51 const VMStateDescription vmstate_clock = {
52     .name = "clock",
53     .version_id = 0,
54     .minimum_version_id = 0,
55     .pre_load = clock_pre_load,
56     .fields = (const VMStateField[]) {
57         VMSTATE_UINT64(period, Clock),
58         VMSTATE_END_OF_LIST()
59     },
60     .subsections = (const VMStateDescription * const []) {
61         &vmstate_muldiv,
62         NULL
63     },
64 };
65