xref: /openbmc/qemu/hw/isa/apm.c (revision b91a0fa7)
1 /*
2  * QEMU PC APM controller Emulation
3  * This is split out from acpi.c
4  *
5  * Copyright (c) 2006 Fabrice Bellard
6  *
7  * This library is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License version 2.1 as published by the Free Software Foundation.
10  *
11  * This library is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with this library; if not, see <http://www.gnu.org/licenses/>
18  *
19  * Contributions after 2012-01-13 are licensed under the terms of the
20  * GNU GPL, version 2 or (at your option) any later version.
21  */
22 
23 #include "qemu/osdep.h"
24 #include "hw/isa/apm.h"
25 #include "hw/pci/pci.h"
26 #include "migration/vmstate.h"
27 #include "trace.h"
28 
29 
30 /* fixed I/O location */
31 #define APM_STS_IOPORT  0xb3
32 
33 static void apm_ioport_writeb(void *opaque, hwaddr addr, uint64_t val,
34                               unsigned size)
35 {
36     APMState *apm = opaque;
37     addr &= 1;
38 
39     trace_apm_io_write(addr, val);
40     if (addr == 0) {
41         apm->apmc = val;
42 
43         if (apm->callback) {
44             (apm->callback)(val, apm->arg);
45         }
46     } else {
47         apm->apms = val;
48     }
49 }
50 
51 static uint64_t apm_ioport_readb(void *opaque, hwaddr addr, unsigned size)
52 {
53     APMState *apm = opaque;
54     uint32_t val;
55 
56     addr &= 1;
57     if (addr == 0) {
58         val = apm->apmc;
59     } else {
60         val = apm->apms;
61     }
62     trace_apm_io_read(addr, val);
63 
64     return val;
65 }
66 
67 const VMStateDescription vmstate_apm = {
68     .name = "APM State",
69     .version_id = 1,
70     .minimum_version_id = 1,
71     .fields = (VMStateField[]) {
72         VMSTATE_UINT8(apmc, APMState),
73         VMSTATE_UINT8(apms, APMState),
74         VMSTATE_END_OF_LIST()
75     }
76 };
77 
78 static const MemoryRegionOps apm_ops = {
79     .read = apm_ioport_readb,
80     .write = apm_ioport_writeb,
81     .impl = {
82         .min_access_size = 1,
83         .max_access_size = 1,
84     },
85 };
86 
87 void apm_init(PCIDevice *dev, APMState *apm, apm_ctrl_changed_t callback,
88               void *arg)
89 {
90     apm->callback = callback;
91     apm->arg = arg;
92 
93     /* ioport 0xb2, 0xb3 */
94     memory_region_init_io(&apm->io, OBJECT(dev), &apm_ops, apm, "apm-io", 2);
95     memory_region_add_subregion(pci_address_space_io(dev), APM_CNT_IOPORT,
96                                 &apm->io);
97 }
98