xref: /openbmc/qemu/hw/isa/apm.c (revision dccdb0f82a0d018443b12fb13d91655a10b0a151)
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