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/sysbus.h" 27 #include "migration/vmstate.h" 28 #include "trace.h" 29 #include "qemu/error-report.h" 30 #include "qemu/module.h" 31 32 typedef struct { 33 MemoryRegion iomem; 34 uint32_t chip_size; 35 char *filename; 36 FILE *file; 37 uint8_t *contents; 38 } NvRamState; 39 40 static uint64_t nvram_read(void *opaque, hwaddr addr, unsigned size) 41 { 42 NvRamState *s = opaque; 43 uint32_t val; 44 45 val = s->contents[addr]; 46 trace_nvram_read(addr, val); 47 return val; 48 } 49 50 static void nvram_write(void *opaque, hwaddr addr, uint64_t val, 51 unsigned size) 52 { 53 NvRamState *s = opaque; 54 55 val &= 0xff; 56 trace_nvram_write(addr, s->contents[addr], val); 57 58 s->contents[addr] = val; 59 if (s->file) { 60 fseek(s->file, addr, SEEK_SET); 61 fputc(val, s->file); 62 fflush(s->file); 63 } 64 } 65 66 static const MemoryRegionOps nvram_ops = { 67 .read = nvram_read, 68 .write = nvram_write, 69 .impl = { 70 .min_access_size = 1, 71 .max_access_size = 1, 72 }, 73 .endianness = DEVICE_LITTLE_ENDIAN, 74 }; 75 76 static int nvram_post_load(void *opaque, int version_id) 77 { 78 NvRamState *s = opaque; 79 80 /* Close file, as filename may has changed in load/store process */ 81 if (s->file) { 82 fclose(s->file); 83 } 84 85 /* Write back nvram contents */ 86 s->file = s->filename ? fopen(s->filename, "wb") : NULL; 87 if (s->file) { 88 /* Write back contents, as 'wb' mode cleaned the file */ 89 if (fwrite(s->contents, s->chip_size, 1, s->file) != 1) { 90 printf("nvram_post_load: short write\n"); 91 } 92 fflush(s->file); 93 } 94 95 return 0; 96 } 97 98 static const VMStateDescription vmstate_nvram = { 99 .name = "nvram", 100 .version_id = 0, 101 .minimum_version_id = 0, 102 .post_load = nvram_post_load, 103 .fields = (VMStateField[]) { 104 VMSTATE_VARRAY_UINT32(contents, NvRamState, chip_size, 0, 105 vmstate_info_uint8, uint8_t), 106 VMSTATE_END_OF_LIST() 107 } 108 }; 109 110 #define TYPE_DS1225Y "ds1225y" 111 #define DS1225Y(obj) OBJECT_CHECK(SysBusNvRamState, (obj), TYPE_DS1225Y) 112 113 typedef struct { 114 SysBusDevice parent_obj; 115 116 NvRamState nvram; 117 } SysBusNvRamState; 118 119 static void nvram_sysbus_realize(DeviceState *dev, Error **errp) 120 { 121 SysBusNvRamState *sys = DS1225Y(dev); 122 NvRamState *s = &sys->nvram; 123 FILE *file; 124 125 s->contents = g_malloc0(s->chip_size); 126 127 memory_region_init_io(&s->iomem, OBJECT(s), &nvram_ops, s, 128 "nvram", s->chip_size); 129 sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->iomem); 130 131 /* Read current file */ 132 file = s->filename ? fopen(s->filename, "rb") : NULL; 133 if (file) { 134 /* Read nvram contents */ 135 if (fread(s->contents, s->chip_size, 1, file) != 1) { 136 error_report("nvram_sysbus_realize: short read"); 137 } 138 fclose(file); 139 } 140 nvram_post_load(s, 0); 141 } 142 143 static Property nvram_sysbus_properties[] = { 144 DEFINE_PROP_UINT32("size", SysBusNvRamState, nvram.chip_size, 0x2000), 145 DEFINE_PROP_STRING("filename", SysBusNvRamState, nvram.filename), 146 DEFINE_PROP_END_OF_LIST(), 147 }; 148 149 static void nvram_sysbus_class_init(ObjectClass *klass, void *data) 150 { 151 DeviceClass *dc = DEVICE_CLASS(klass); 152 153 dc->realize = nvram_sysbus_realize; 154 dc->vmsd = &vmstate_nvram; 155 dc->props = nvram_sysbus_properties; 156 } 157 158 static const TypeInfo nvram_sysbus_info = { 159 .name = TYPE_DS1225Y, 160 .parent = TYPE_SYS_BUS_DEVICE, 161 .instance_size = sizeof(SysBusNvRamState), 162 .class_init = nvram_sysbus_class_init, 163 }; 164 165 static void nvram_register_types(void) 166 { 167 type_register_static(&nvram_sysbus_info); 168 } 169 170 type_init(nvram_register_types) 171