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 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 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 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 = (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 }; 120 121 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 }; 150 151 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 }; 166 167 static void nvram_register_types(void) 168 { 169 type_register_static(&nvram_sysbus_info); 170 } 171 172 type_init(nvram_register_types) 173