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