1 /*
2 * QEMU NVRAM emulation for DS1225Y chip
3 *
4 * Copyright (c) 2007-2008 Hervé Poussineau
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to deal
8 * in the Software without restriction, including without limitation the rights
9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10 * copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22 * THE SOFTWARE.
23 */
24
25 #include "qemu/osdep.h"
26 #include "hw/qdev-properties.h"
27 #include "hw/sysbus.h"
28 #include "migration/vmstate.h"
29 #include "trace.h"
30 #include "qemu/error-report.h"
31 #include "qemu/module.h"
32 #include "qom/object.h"
33
34 typedef struct {
35 MemoryRegion iomem;
36 uint32_t chip_size;
37 char *filename;
38 FILE *file;
39 uint8_t *contents;
40 } NvRamState;
41
nvram_read(void * opaque,hwaddr addr,unsigned size)42 static uint64_t nvram_read(void *opaque, hwaddr addr, unsigned size)
43 {
44 NvRamState *s = opaque;
45 uint32_t val;
46
47 val = s->contents[addr];
48 trace_nvram_read(addr, val);
49 return val;
50 }
51
nvram_write(void * opaque,hwaddr addr,uint64_t val,unsigned size)52 static void nvram_write(void *opaque, hwaddr addr, uint64_t val,
53 unsigned size)
54 {
55 NvRamState *s = opaque;
56
57 val &= 0xff;
58 trace_nvram_write(addr, s->contents[addr], val);
59
60 s->contents[addr] = val;
61 if (s->file) {
62 fseek(s->file, addr, SEEK_SET);
63 fputc(val, s->file);
64 fflush(s->file);
65 }
66 }
67
68 static const MemoryRegionOps nvram_ops = {
69 .read = nvram_read,
70 .write = nvram_write,
71 .impl = {
72 .min_access_size = 1,
73 .max_access_size = 1,
74 },
75 .endianness = DEVICE_LITTLE_ENDIAN,
76 };
77
nvram_post_load(void * opaque,int version_id)78 static int nvram_post_load(void *opaque, int version_id)
79 {
80 NvRamState *s = opaque;
81
82 /* Close file, as filename may has changed in load/store process */
83 if (s->file) {
84 fclose(s->file);
85 }
86
87 /* Write back nvram contents */
88 s->file = s->filename ? fopen(s->filename, "wb") : NULL;
89 if (s->file) {
90 /* Write back contents, as 'wb' mode cleaned the file */
91 if (fwrite(s->contents, s->chip_size, 1, s->file) != 1) {
92 printf("nvram_post_load: short write\n");
93 }
94 fflush(s->file);
95 }
96
97 return 0;
98 }
99
100 static const VMStateDescription vmstate_nvram = {
101 .name = "nvram",
102 .version_id = 0,
103 .minimum_version_id = 0,
104 .post_load = nvram_post_load,
105 .fields = (const VMStateField[]) {
106 VMSTATE_VARRAY_UINT32(contents, NvRamState, chip_size, 0,
107 vmstate_info_uint8, uint8_t),
108 VMSTATE_END_OF_LIST()
109 }
110 };
111
112 #define TYPE_DS1225Y "ds1225y"
113 OBJECT_DECLARE_SIMPLE_TYPE(SysBusNvRamState, DS1225Y)
114
115 struct SysBusNvRamState {
116 SysBusDevice parent_obj;
117
118 NvRamState nvram;
119 };
120
nvram_sysbus_realize(DeviceState * dev,Error ** errp)121 static void nvram_sysbus_realize(DeviceState *dev, Error **errp)
122 {
123 SysBusNvRamState *sys = DS1225Y(dev);
124 NvRamState *s = &sys->nvram;
125 FILE *file;
126
127 s->contents = g_malloc0(s->chip_size);
128
129 memory_region_init_io(&s->iomem, OBJECT(s), &nvram_ops, s,
130 "nvram", s->chip_size);
131 sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->iomem);
132
133 /* Read current file */
134 file = s->filename ? fopen(s->filename, "rb") : NULL;
135 if (file) {
136 /* Read nvram contents */
137 if (fread(s->contents, s->chip_size, 1, file) != 1) {
138 error_report("nvram_sysbus_realize: short read");
139 }
140 fclose(file);
141 }
142 nvram_post_load(s, 0);
143 }
144
145 static Property nvram_sysbus_properties[] = {
146 DEFINE_PROP_UINT32("size", SysBusNvRamState, nvram.chip_size, 0x2000),
147 DEFINE_PROP_STRING("filename", SysBusNvRamState, nvram.filename),
148 DEFINE_PROP_END_OF_LIST(),
149 };
150
nvram_sysbus_class_init(ObjectClass * klass,void * data)151 static void nvram_sysbus_class_init(ObjectClass *klass, void *data)
152 {
153 DeviceClass *dc = DEVICE_CLASS(klass);
154
155 dc->realize = nvram_sysbus_realize;
156 dc->vmsd = &vmstate_nvram;
157 device_class_set_props(dc, nvram_sysbus_properties);
158 }
159
160 static const TypeInfo nvram_sysbus_info = {
161 .name = TYPE_DS1225Y,
162 .parent = TYPE_SYS_BUS_DEVICE,
163 .instance_size = sizeof(SysBusNvRamState),
164 .class_init = nvram_sysbus_class_init,
165 };
166
nvram_register_types(void)167 static void nvram_register_types(void)
168 {
169 type_register_static(&nvram_sysbus_info);
170 }
171
172 type_init(nvram_register_types)
173